lab exam
What are the American National Standard Institute minimum standards for humidification ?
- Normal = 44 mg/L or 100% - Upper airway = output of 10 mg/L for unheated/50% relative humidity at room temperature (22*C) - Lower airway = at least 30 mg/L heated (100% at 30*C)
Why are respiratory patients special ?
- Often have SUPER (0% humidity) dry gases delivered to them - Have bypassed normal upper airway that you need to heat and humidify
What two factors determine harmful effects of oxygen toxicity?
- PO2 - higher (higher FiO2 causes) - Exposer time - longer
Jet Nebulizer: Small Volume Nebulizer (SVN) generally produce aerosol particles that range in size from ___to ___ µ in diameter.
1.5 to 7
How do you assemble and check the equipment for endotracheal intubation?
1.check all equipment including laryngoscope, ET tube, O2, suction, etc. 2. Lock laryngoscope blade onto handle and check light.
what factors are used to determine airway of choice?
1.specific needs of pt (pre-op, upper airway obstruction, acute respiratory failure, long term vent, etc.) 2. skill&experience needed to insert airway 3. cost
Liquefaction of secretion using Ultrasonic Nebulizers (USN) is a ~ ___ minute treatment.
10
Particles which are > _____ µ do not get past the nose. Deposited in nasal and oral cavities.
10
how long does a breathing treatment usually last? ____ minutes
10
When is a humidifier ineffective ?
10 L/m
FIO2 for nasal cannula?
4% for every L starting at 20 -1L = 24% -2L = 28% 24-44%
A Micro-Nebulizer delivers ≤ ___ ml.
5
What is the minimum flow necessary to prevent CO2 accumulation in a simple mask?
5 L/min
flow rate of a mask with reservoir?
5 L/min
Advantages of MDI over SVN Of the medication placed in a SVN, even under the best of condition, only about ___ - ___% actually enters the patient's lungs. The other ___ -___% is wasted medication. Compare this to the MDI, which, especially when combined with a _____, results in nearly all of the dosage entering the lungs. That is why, next year when you look at typical dosages, a much larger amount of liquid medication is required to obtain the same effect as a small amount of the same medication delivered by MDI.
5%; 10%; 90%; 95%; spacer
Particle sizes of aerosols range from...
5-50 microns
How long will it take for a healthy person being manually ventilated for their SaO2 to drop below 90%?
5-7 mins This is due to their Functional Reserve Capacity
operate at about
70% efficacy rate
HME returns
70% of heat and moisture from expired gas on the next inspiration
HME's should operate with at least ? efficiency rate
70%, or 30 mg/L of water
The efficiency of these devices varies between manufactures, usually producing from ____% to ____% relative humidity at temperatures of 30o or 31o C.
70%; 90%^
What are the overall factors affecting humidity ?
- Temperature = greatest effect of all/heating allows for increased humidity - Length of time = longer contact time increases humidity - Surface area = greater the surface area increases humidity
Factors influencing volume of condensate formed
- Temperature difference across the system - Ambient temperature - Gas flow - Set airway temperature - Length, diameter, and thermal mass of the breathing circuit
What happens when there is to much water in tubing ?
- The oxygen concentration is increased as the water acts as a restriction that messes up the entrainment ratios of the venturi device (increases FiO2)
What are the hazards of an HME ?
- Thickened and increased volume of secretions - Fluid overload
What are the types of low-flow humidifiers ?
- Unheated - Bubble
What are the indications for humidity therapy ?
- Upper airway inflammation (Croup and post extubation) reduces swelling with vasoconstriction - Humidity deficit - Sputum induction
What is compromised ITB ?
- Upper airway is bypassed with an artificial airway - Environmental temperature or humidity drops - Tidal volumes (breathing increased)
What are bubble humidifiers ?
- Used with only nasal cannula - Adjust flow from 1-6 L/m - Does not do well with high flows from flowmeter
clinical examples of hypoxic hypoxia (hypoxemia)
-altitude -O2 equipment error -drug overdose -COPD exacerbation -emphysema -pulmonary fibrosis -asthma -pulmonary emboli -atelectasis -cyanotic congenital heart disease
pathophysiology of hypoxic hypoxia
-alveolar hypoventilation (increase PaCO2) -pulmonary diffusion defect (decrease PaO2) -pulmonary V/Q mismatch -R to L shunt -barometric pressure decrease or FIO2 <0.21
clinical examples of hemic hypoxia
-anemias -carboxyhemoglobinemia -methemoglobinemia
how do you position the airway for the LMA?
-extend head and flex neck -avoid LMA fold over: assistant pulls lower jaw down visualize posterior oral airway ensure that LMA isn't folding over in the oral cavity as it's inserted
what are the hazards of a LMA?
-failure to press deflated mask against hard palate or inadequate lubrication or deflation can cause the mask tip to fold back on itself -once mask tip has started to fold over it may progress pushing epiglottis into its downfolded position causing mechanical obstruction -if mask tip is deflated forward it can push down epiglottis causing obstruction -if inadequately deflated it may push down the epiglottis or penetrate the glottis
clinical examples of demand hypoxia
-fever -seizures
what are the landmarks for general OAW sizing?
-flange at corner of mouth -tip at jaw angle
What are the indications for a double lumen ETT?
-independent lung ventilation -allow for lung isolation -all for differential ventilation of both lungs -allow for application of CPAP to a nonventilated lung to prevent atelectasis -improves effectiveness of suctioning
What are the advantages of a tracheostomy tube?
-long term use more than 14days -no complications with upper airway -best tolerated of all airways -easiest to stabilize -easier to suction/clean
how do you examine the LMA?
-visually inspect cuff for tears or other abnormalities -inspect the tube to ensure that is is free of blockage or loose particles -deflate cuff to ensure that it will maintain a vacuum -inflate cuff to ensure that it doesn't leak
Types of Humidifiers
Bubble Humidifiers Passover Humidifiers Heat & Moisture Exchangers Heated Humidifier Systems
Three types of humidifiers?
Bubble, passover and HME
Disadvantage of bubble humidifier
Bubblers are water reservoir, they can support the growth of Pseudomonas aeruginosa. Improperly handled humidifiers have been linked to nosocomial respiratory infections with this pathogen
How can water in ventilator tubing be limited ?
By using heated wires in tubing
Device used to deliver a precise FIO2
Air Oxygen Blenders
What are the 2 gas sources for Air Oxygen Blenders?
Air and Oxygen (O2)
Once flow rate of a nasal cannula hits 6L/M what happens to the air flow?
Air flow becomes turbulent, so any rate above 6 will not be beneficial.
Jet Nebulizer: Continuous Medication Nebulizer (a HART or HOPE nebulizer) are designed to deliver a consistent amount of medication to the ______ over several hours (as opposed to the SVN that is used for ______ medication delivery).
Airway; intermittent
Air and oxygen entering the blender are first directed into two chambers on opposite sides of a __________.
Diaphragm
What is the humidity deficit?
Difference between inspired gas' water content and water content of a gas at body temperature BH-AH
What is body (humidity) deficit ?
Difference between measured and fully saturated/amount needed to achieve full saturation at that temperature
By adding _____________ is the only way to make the bubble humidifier more efficient.
Diffuser
What humidifier increases surface area of gas ?
Diffuser humidifier
What type of Humidifier functions by having gas travel down a tower, through a one-way valve, into a diffusion grid. The gas then travels back up through the grid from underneath, picking up the moisture and delivering it to the patient?
Diffuser/Cascade Heated Humidifier
A _____________ can be added to the bubble humidifier to break the air into smaller bubbles within the reservoir. What is the purpose of this?
Diffuser; small bubbles increases the surface area of the gas increasing the humidity output.
Jet Nebulizer: The particle size can be influenced slightly by varying the gas _______...higher flowrates tend to produce (smaller/larger) particles, while lower flowrates tend to produce (smaller/larger) particles.
Flowrate;smaller; larger
Ultrasonic Nebulizers (USN) Hazards: ______ ______ -- this nebulizer can nebulizer up to 6 cc per min of fluid.
Fluid overload
Question 2 Given the water vapor content of a gas be able to determine the humidity deficit
Humidity deficit = capacity - content for body humidity it would be 44mmHg - content 44mmHg - content (absolute humidity 10) = 34mmHg
As the water in the reservoir becomes less in the bubble humidifier, what happens to humidity output?
Humidity output decreases. As my reservoir lessens, the time and contact increases so my output decreases as well.
A Large Volume Nebulizer (LVN) are used to treat _______ deficit associated with _______ airways.
Humidity; artificial
When the patients upper airway is bypassed, what must be done to ensure adequate humidification?
Traditionally HME have been limited to providing humidification to patient with artificial airway who require ventilatory support
A diffusion dependent monitor that reads diffusion of O2 to the skin
Transcutaneous Monitor
A monitor that uses a heated probe and diffusion to read TC CO2 and CO2 Levels.
Transcutaneous Monitor
(True/False) The wick is more efficient than the bubble even without heating it.
True
(True/False) Whenever ample gas is administered, it has to be verified.
True
T or F Absolute humidity is when the gas is fully saturated with water vapor
True
True/ False. Use of an HME increases dead space and PaCO2 and may increase ventilatory requirements for patients who are mechanically ventilated.
True. HMEs contribute additional dead space, which can increase the ventilation requirement and PaCO2 .
If the HD is high past the ISB the gel layer will?
add water to decrease it
Nebulizer
aerosol creating mist
What is the difference between humidity and aerosol?
aerosol is visible
What is the biggest problem in spreading infection?
aerosol particles or liquid in circuits
What is the process of humidity therapy?
The nose heats and humidifies gas on inspiration, while cooling and reclaiming H2O from the gas that is exhaled
What is the body's normal humidifier ?
The nose which adds heat and moisture to the inspired gas
What are the benefits of a combitube?
low price, all in one device noninvasive no prep necessary rapid and easy intubation immediate fixation prevention of aspiration
What is the design of an ETT?
made out of Polyvinyl Chloride stamped with IT-Z79= implant tested & safe for use I.D.= internal diameter O.D. = outside diameter 2cm markings from distal end of tube
unconscious patient breathing with patent airway
maintain O2
what are the goals of humidification?
maintain normal physiologic conditions by providing heat and humidity to inspired gas
What is the purpose of an airway cuff?
maintains sealed airway allowing for mech ventilation protects from aspiration
Jet Nebulizer: Small Volume Nebulizer (SVN) are primarily used for short-term, intermittent ______________ delivery.
medication
MDI (Metered Dose Inhalers) Because less medication is deposited in the mouth there tends to be fewer _______ side effects.
medication
Aerosol Therapy Objectives: To deliver _____ to specific areas of the pulmonary system.
medications
absolute humidity is measured in _____
mg/L
absolute humidty is measured in
mg/L
what are cilia?
microscopic hair-like structures that beat in a wave-like motion this allows particles to be captured and transported out of the airways
relative contraindications
might be a problem so be careful and just watch the patient carefully
how to get water out of tubing
milk the tubing into the trash
What are 2 other monitoring methods?
minimal leak technique minimal occluding volume
You want to see ___ coming out of the SVN to assure it is working correctly?
mist
If pt is nose breathing and not mouth breathing with an SVN taking a tx how would you know?
mist disappears on inspiration with breathing by mouth correctly
types of jet reservoirs that provide a higher flow
misty ox and mistogen
water vapor pressure (pH2O) is measured in
mm or torr
vapor pressure is expressed in _____
mmHg or torr
water vapor pressure (ph2o) is measured in _______
mmHg or torr
What does each variable mean in the law?
n=viscosity of fluid l= length of tube r=radius of tube
A cooperative and alert postoperative patient taking food orally requires a low percentage of oxygen to be provided continuously. A precise oxygen concentration is not needed. What is the best choice for this patient?
nasal canula.
device that produces an aerosol
nebulizer
places for contamination
nebulizers, O2 equp., and water reserviors
places for contamination
nebulizers, oxygen equipment, water reservoirs
Troubleshooting with a SPAG
need to check for hospital protocol
good for sputum induction
normal saline, hypertonic solution, hypotonic solution, or sterile water
what might be in a med cup in an ultrasonic?
normal saline, hypertonic solution, hypotonic solution, or sterile water
simple condenser (HME)
on insp air cools condenser element, on exp water vapor condenses directly on it's surface and warms it. on next insp cool, dry air is warmed and humidified as it passes over condenser. 50% pt moisture is recapture
two flow meters inside the SPAG unit
one powers the drying unit (makes particles smaller) and the other powers the flow to the patient
What is a Passy Muir Talking Valve?
one way valve that allows talking while keeping tube in place allows inhalation through trach tube but exhaled air must pass through vocal cords to nose and mouth
Length of airways and viscosity of air cannot vary so?
only the radius of airway can change
Which two entrances can an ETT be inserted?
orally or nasally
What are your airway choices?
oropharyngeal nasopharyngeal laryngeal mask airway esophageal obturator oral ETT combitube tracheostomy tube
Why does the air have to be body temp?
otherwise cells will die
What should be done with the cap of a Bivona cuff?
pilot balloon should be left uncapped or connected to ventilator pressure line
Metered Dose Inhalers (MDI) Must ______ inhaler if more than ½ day from last accuation.
prime
what is evaporation?
process by which fluid changes to a vapor, aided by heat
what is rehydration?
process of restoring lost water to the body tissues or cells
What are goblet cells?
produce mucus/defense cells
What are the key factors to preventing tracheal stenosis?
proper cuff inflation and support of ventilator tubing
What is necessary to gain proficiency in ETT?
proper training and practice
what is a mid-flow humidifier?
allows increased flow using a nasal cannula unheated and flows from 6-15LPM audible pressure pop off and pressure relief port FiO2 depends on Tv and RR FiO2 can be as high as 100% w/ certain pts
don't use HME if pt is having?
alot of secretions bc it will cause an increase in plugging
misty ox and mistogen
provide a higher flow than Aqua Pak
What are epithelial cells?
provide protection lining
what's the main purpose of the nasal cannula?
provide supplemental O2 in the spontaneously breathing patient
what is the design of the LMA?
provides oval seal around laryngeal inlet, once it is inserted and cuff is inflated
Prior to removing an esophageal obturator what must happen?
pt must be intubated and cuff inflated to prevent aspiration
PHNS
public hospital service networks
with heated humidifiers what occurs
rain out
What does a decreased FRC lead to?
rapid desaturation
the dial in front on an USN controls the
amplitude of the piezoelectric transducer
What is the best way to prevent aspiration?
an ETT tube with cuff patients that may vomit like drug OD or alcohol
Hypoxemia
an abnormal deficiency of oxygen in the arterial blood
what is an esophageal obturator used for?
an emergency airway
oxygen coming out of the wall and cylinders is _______
anhydrous
types of jet reservoirs
aquapak, misty ox, and mistogen
When the upper airway has been bypassed or is insuffiecient aerosol therapy is necessary to
assure humidification of inspired gases.
use bubble humidifier?
at 4-5 LPM on BNC or by docs orders
Inspired air must be?
at body temp and be fully saturated by the time it reaches the carina
when should an esophageal obturator be removed?
at peak inhalation
once inserted where does the LMA lie?
at the crossroads of the digestive and respiratory tracts
return capillar
returns lare particles of water back into bottle
SPAG troubleshooting
check hospital protocol for flow meter settings in each chamber and the pressure set to run the unit
if pt is having plugging or increased secretions while using an HME, you should....
chg to heated moisture
Jet Nebulizer: Continuous Medication Nebulizer (a HART or HOPE nebulizer) are specifically designed for continuous nebulization of medication, especially _____________________.
children
wick uses capillary action to
continually draw water from the reservoir and keeps the wick saturated
Polarographic Analyzer: Also provides a _________ reading of FIO2.
continuous
ultrasonic nebulizers should not be given _______
continuously
A medicine container is placed in the
cuplet on an USN
What is a high volume low pressure cuff?
cylindrical shape with large surface area inflates evenly which conforms to tracheal shape produces low pressure on wall due to large contact area most commonly used
Uses of a jet reservior
delivery of O2 with humidification
uses of jet intermittent
delivery of aersolized medication
uses of a jet reservoir
delivery of oxygen with humidification
uses for SPAG
delivery of ribavirin
bland aerosol therapy involves
delivery of sterile water or hypotonic, isotonic or hypertonic saline solution
water accumulates in the _______ portion of the large bore tubing
dependent
what is the size of a child NAW?
diameter: 12F (about 3mm ETT) to 36F
water accumulated in the tubing increases the Fio2 and decreases the _____
flow
if the ______ is set too high, water will collect quickly in the tubing
flow meter
Question #8 bubble humidifier most commonly used
flows are greater than 4L/min on low O2 device bubble humidifier would be added
Question #11 at what level may use of humidifiers be unnecessary 4 pt receiving low flow O2 therapy?
flows that are at or below 4L/min low O2 devices
what would you check the hospital protocol for when using a SPAG
flowsettings in each chamber and pressure set to run the unit
What is a Bivona cuff?
foam cuff that automatically inflates based on atm pressure don't inflate with syringe Kamen Wilkinson Fome Cuff is same but diff manufacturer
the ______ of an ultrasonic is set at the factory
frequency
What neck size makes intubation difficult?
greater than 40 cm is a good indicator that it will be difficult
How do you insert the laryngoscope?
handle in left insert in right side of mouth
electricity is needed to
heat the system (increases safety risk)
What is a fenestrated trach?
hole is in outer cannula facilitates weaning-upper airway ventilates can talk through
The fio2 of USN is .21% but if pt needs a higher demand you can
hook the USN to their O2 port
water in a vaporous or molecular form
humidity
amount of water vapor that must be added to a gas to achieve 100% humidity at a specific temperature
humidity deficit
changes in room temp cause
humidity to fall out or rain out into the tubing
by increasing the humidity and restoring mucousal blanket it
hydrates dry, retained secretions, promotes expectoration, and improves cough effectiveness
retained secretions are _______ (water loving)
hydrophillic
Retained secretions are
hydrophillic (water loving)
Question 36 What device could be used to monitor humidity levels in a ventilator circuit?
hygrometer
What device could be used to monitor humidity levels in a ventilator circuit?
hygrometer
during inspiration the lower water vapor pressure in the inspired gas separates water molecules from the
hygroscopic salt without cooling
material for hygroscopic is impregnated with
hygroscopic salt, captures the moisture from exhaled gas
HTTP
hypertext transmission protocol -Internet protocol used to transmit web pages -World wide web technology. Its the set of rules that govern the software that transports hyperlinked files along internet
the only med's you can use in med container on an USN is?
hypertonic saline, hypotonic saline or sterile water
What are some complications of a PMV?
if humidified air is used the valve may stick increased WOB may occur during PMV use
How do you know if someone is ready to be extubated?
if the machine reads less than given through the tube it means the air went out of the mouth
applying dry gas at over 4LPM to upper airway causes?
immediate heat and water loss
hypoxemia (again...)
inadequate O2 tension in blood characterized by PaO2 <80 mmHg
What is the minimal occluding volume?
inflate cuff til the airflow heard escaping around cuff ceases during inspiration prevents loss of TV and decreases risk of aspiration
what is the minimal leak technique?
inflate cuff until any air leak stops slowly remove a small amount of air until a small air leak is heard at peak inspiration shouldn't be used bc it increases risk of aspiration
what are the advantages of an esophageal obturator?
insertion doesn't require visualization no equipment needed to insert tube prevents air from entering stomach ET may still be inserted with EOA in place prevents vomit from traveling up esophagus
what are the 4 types of HMEs?
simple HME HME with filter (HMEF) Hygroscopic Condenser Humidifier (HCH) HCH with filter (HCHF)
three types of HME's
simple condenser, hygroscopic condenser, hydrophobic condenser
dont use a bubble humidifier on
simple or venti mask
low pressure at the jet draws fluid from the reservoir up to the top of the
siphon that shatters it into small liquid particles (Bernoulli's principle)
What are the sizes for LMA?
size 1-2.5 for 1-25 kg children size 3 for >30kg kids and small adults size 4 for adult size 5 for large adult/poor seal with size 4
What are the steps of LMA insertion?
size selection examination of the LMA check deflation and inflation of cuff lubrication of LMA position airway
What is a low-volume high pressure cuff?
small contact area with tracheal wall inflates unevenly causing uneven pressure exceeds safe pressure limits due to low vol rarely used
What is a characteristic of automatic reservoir feed systems
small inlet can be attached to a gravity-fed intravenous type bag and the tubing allows refilling without interruption. Floatation valve controls can be used to maintain humidifier reservoir fluid volume.
SPAG
small particle aerosol generator
SPAG AKA
small particle aerosol generator
How do you position a patient for ET intubation?
sniffing position-aligns airway
Both gases must be at equal psig or a reed alarm will ________.
sound
MDI (Metered Dose Inhalers) The use of the ______ allows MDIs to be used on younger patients with the use of a mask.
spacer
the greater the area of contact between the water and the gas ...
the greater the evaporation
the smaller the particles the higher the mist density therefore
the greater the surface area
the smaller the particles,
the higher the mist density, and therefore, the greater the surface area
the wick draws water into
the honey-comb like structure by means of capillary action
water vapor molecules easily pass through the membrane but
the liquid water cannot
Water vapor molecules easily pass through the membrane, but
the liquid water cant
what is the disadvantage of a Guedel airway?
the material is made of semi-rigid material which may occlude tube if pt bites down before it is completely inserted
maximum absolute humidity
the max amount of water vapor a gas can hold at a given temperature
Remaining small particles leave the nebulizer through
the outlet port
What is the #1 cause of airway obstruction?
the tongue most frequently seen in unconscious patient
heated humidifier systems are most often used when
the upper airway is bypassed for an extended period of time
After the cough?
the viscosity increases again. it thickens after each cough ends to keep it from falling back down the airway to keep it moving up go against gravity
The nose does most of?
the warming and humidification due to its high vascularity of mucosal lining
absolute humidity
the weight of water vapor in a gas volume mg of H2O/L of gas
Capillary action continually draws water from the reservoir and keeps
the wick saturated
if you hear a whistling sound
there is a kink in tubing
hygroscopic condenser uses a
thermal element of low thermal conductivity, paper wool foam
use an USN for
thick inspiratory secretions
Will not thin secretions that are?
thickened due to a physiologic process
When are airways needed to be individually ventilated?
thoracic surgery pulmonary infection severe hypoxemia due to unilateral lung disease
Where is the esophageal obturator inserted?
through mouth and into esophagus minimal skill required as vocal cords and trachea don't need to be visualized
HME troubleshooting: if patient coughs any sputum into HME, what should be done?
throw it away and replace
what are the disadvantages of an esophageal obturator?
tight mask seal must be maintained may cause trauma to esophagus or airway can be easily misplaced in trachea can't be left in place for prolonged periods (2hrs max) tracheobronchial suctioning can't be performed doesn't isolate trachea and prevent aspiration of upper airway contents
Reservoir and Feed Systems
to avoid constant filling, incorperate a large water reservoir or use a gravity feed system.
NEVER leave your patient alone on a(n)
ultrasonic nebulizer
troubleshooting for an ultrasonic: if there is no mist
unplug and check the transducer, check the med cup
if no mist on USN when you plug in
unplug and check transducer and check medicine cup
What is the automatic cuff pressure monitoring?
until recently limited commercial availability extra weight on ET tube allows for pressure to enter chamber during a cough and then replenishes the pressure afterwards
Question #12 If pt upper airway bypassed, what must be done to ensure adequate humidification?
use wick passover humidifier - used on pt with bypassed airway, mechanically ventilated
What is a capnometer?
used to detect exhaled CO2 its attached to the end of the ET tube and measures the CO2 value on exhalation
What is the tracheal button?
used to maintain patency of tracheal stoma upper airway ventilates patient may be suctioned via button
what is a HMEF?
uses a hydrophobic ceramic filter and can be 99.9% effective in removing bacteria and viruses
what is a simple HME?
uses aluminum with or without fibrous coating for internal components least efficient for providing humidity
it is expressed in mm or torr
vapor pressure
pressure exerted by water vapor molecules in a given volume of gas
vapor pressure
What do you look for as your guide to inserting the tube?
visualization of the vocal cords
What are the functions of the upper airway?
warm, filter, humidify inspired air
How do you insert the ET tube?
watch tube go through glottis insert to the 21-23 cm marking at the teeth remove stylette if used and inflate cuff w/ 5-7ml of air using a syringe
___ could accumilate in dependant portion of tubing on the USN
water
membrane type humidifier
water and gas seperated by hydrophobic membrane, water vapor can pass through but liquid water cant
contact time depends upon the depth of the
water column
Humidity
water in a vaporous or molecular form
for aerosol, we disperse the
water into the gas (nebulization)
Hydrophobic condenser
water repellant element -70%
what is the sol layer?
watery fluid that covers ciliated cells
ISB can be shifted and altered esp:
when one breaths through the mouth, bypassing the upper airway and not allowing the air to humidify and heat. or when ones minute ventilation is higher than normal.
When does extubation occur?
when the airway is no longer needed; when the indications for its placement no longer exist
how is correct placement of the esophageal obturator achieved?
when the chest rises with ventilation if it doesn't rise the tube is in the trachea
Heated humidifiers always outperform
unheated humidifiers
cooling causes
"rain-out"
relative humidity is measured in
%
relative humidity is measured in ____
%
How do you determine percent body humidity?
%body humidity/100 = x 44 =
What are 5 types of airway appliances?
**Aerosol mask **Face tent **T-tube **Tracheostomy mask
What advantages do Passover devices have over bubble humidifiers?
**Maintains saturation at high flow rates **Adds little to no flow resistance to spontaneous breathing circuits
What are 3 types of HMEs?
**Simple condenser humidifier **Hygroscopic condenser humidifier **Hydrophobic condenser humidifier
What are purposes for administering humidification?
**To administer dry medical gases at flows >4L/min **To overcome a humidity deficit created when the upper airway is bypassed (ET intubation) **To manage hypothermia **To treat cold air bronchospasm
Clinical Signs and symptoms of inadequate airway humidification
*Atelectasis *Dry, nonproductive cough *Increased airway resistance *Increased rate or range of infection *Increased WOB *Pt complaint of substernal pain and airway dryness *Thick, dehydrated secretion
Question 18 What is the *primary goal* of a *heated humidification system?*
*Primary goal* is to *match the output* of the humidifying *device* to the normal *inspiratory conditions* occurring at the *level of the trachea*
What are the principles that affect the quality of performance of a humidifier:
*Temp *Surface Area (greater the area the more for evaporation) *Time of contact (longer gas is in contact with water, the more evaporation) *Thermal Mass (inertia)
Types of humidifiers
*bubble *pass over *HME (heat and moisture exchangers)
Factors that Condensation create in circuits
*temp *ambient temp (surrounding) *the gas flow *the set airway temp *the length, diameter, and thermal mass of breathing circuit
Complication of HME
*tend to decrease at high vols and rates of breathing *High inspiratory flows and high Fi02 levels can decrease HME efficiency *Flow resistance increases after several hours of use due to water absorption
Contraindications of HME with mechanical vent
*thick bloody secretions *expired tidal vols les than 70% *body temp less than 32° C *Spontaneous min vent *receiving aerosol meds
What is a hypertonic solution ?
- (10%) - Sputum inductions - Greater tonicity than surrounding tissues - Tend to draw fluid from surroundings
What is a isotonic solution ?
- (Normal saline) 0.9% breathing Tx - Neither gains or loses water but maintains a steady size - body neutral
What does humidity therapy do ?
- Adds moisture to the gases we breathe - Reduces upper airway swelling - Maintain normal physiological functions - Provide adequte heat/humidity - Aid in the removal of thick secretions - Prevent airway response to cold air
What are the types of high-flow humidifiers ?
- Aerosol set-up - Conca - Wick - HME
What is an HME ?
- Artificial nose - For short term use - Can produce 70-90 % humidity - Should be replaced as needed - Considered a passive humidifier because it uses the patient to heat unit
What is the Isothermic Saturation Boundary (I.S.B.) ?
- At or just below carina (end of trachea) - Point at which inspired gases are fully 100% saturated and warmed by body temperature - 44 mg/L at 37*C
Question #17 purpose bubble "pop off" valve
- Audible pressure relief, sounds 2psi limit, indicate obstruction in tubing -failure to indicate faulty valve or leak -high flow rates aerosol ^risk of infection
What are the hazards of humidity therapy ?
- Bronchospasm to cool mist - Infection - Fluid overload (CHF and newborns especially)
What are types of humidifiers ?
- Bubble - HME - Wick - Cascade/Babington/Passover
What is a large volume jet aerosol humidifier ?
- Called aerosol set-up - Always run at flush - Flow restrictor in most brands limits flow to just 12-13 liters
What is underhumidification ?
- Caused by exposure to dry medical gases - Thickens mucous and retained secretions - Decreased mucocillary transport - Cold can cause bronchospasm
What are the hazards of a heated humidifier ?
- Chance of burns to patients/caregivers - Have to be monitored closley
What can cause upper airway swelling ?
- Croup - Post extubation
Respiratory signs of dehydration ?
- Crusty nasal passages - Thick tenacious secretions - Dry hacking cough - Nosebleeds - Dry mouth
What is a collection bag ?
- Drain bag at lowest loop in circuit to collect water - Placed on both expiratory/inspiratory tubing
Patient-nebulizer Interface
- Face mask - Face tent - Trach collar - T - piece - Enclosures (Mist tents, Oxyhoods)
What are sputum inductions ?
- For patients who are unable to cough up on their own - You nebulize 10% saline solution for 10 minutes - Hypertonic saline draws out water from the tissues of the throat and trachea to help liquify secretions for expectoration so microbes can then be identified
What is body humidity ?
- Fully saturated at body temperature - 100% relative humidity - 43.9 mg/L at 37*C
What are the reasons for using humidity therapy ?
- Humidify gases - Thin secretions - Reduce swelling - Induce sputum samples
What is a hytpotonic solution ?
- Sterile water - Most humidity therapy
bubble humidifier
- System in which dry gas is directed toward the bottom of a water-filled reservoir, where the stream of gas is broken into bubbles that gain humidity as they rise through the water. - Goal is to raise water vapor content of the gas to ambient levels. - Diffuses/breaks gas stream into small bubbles to increase gas contact with the water. - Heaters can be used to increase humidification, but also increases condensation in the tubing delivering gas to the patient. - Spring loaded pop-off valves alert caregivers of an obstructed tubing.
Humidifier performance depends on
- Temperature - Surface area - Time in contact
What is the 50% rule ?
- With very little air entrainment with high oxygen concentrations, total flows are pitiful and you need to double output in creative ways - Most common way is to use 2 nebulizers together in tandem
Complications for setting temperature of humidity levels below 25 mg H2O/L for 1 hour or 30 mg/L for 24 hours or more (low temperatures)
- airway mucosal dysfunction
How much humidity does an HME deliver?
- delivers 26-29 mg H2O/L - may be adequate for patients without underlying conditions that impair airway clearance
Nebulizer
- generates and dispersers small particles of liquid into air as aerosol - Device that produces an aerosol, or suspension, of particles in gas.
Complications for setting temperature above 37°C (high temperatures)
- potential thermal hazard to the patient for gas temperature above 41°C - If the inspired gas has a temperature higher than 37°C and is 100% saturated, condensation occurs, causing reduced mucus viscosity and increased pericellular depth fluid. - mucociliary transport velocity may be reduced - the excess heat also may cause cellular damage.
Question #14 thermal mass effect humidifier performance?
- the greater amount water humidifier greater thermal mass - ^ capacity hold and transfer heat to gases - Larger reservoir humidifier more consistent heat and humidification (G.I.L)
Reasons why humidification is necessary
- to prevent hypothermia, disruption of the airway epithelium, bronchospasm, atelectasis, and airway obstruction
Reservoir or feed systems
-*Heated humidifiers running continuously* can evaporate more than 1 L of H2O per day To avoid constant refilling many have *large reservoir or gravity feed* Ideal system should be safe, easy to set up, dependable and allow for continuity of therapy when reservoirs being filled -Large reservoir still require filling Interruption of mechanical ventilation Potential for contamination *-Gravity feed systems require constant checking and opening of valve danger system could run dry* -Membrane cartridge systems are now being used to humidify high flow nasal cannula for adults and infants
What type of heating elements possible for heated humidification?
-*Hot plate* at base of humidifier -*Wraparound* which covers humidifier chamber -*Yolk or collar element* -*Immersion type* -*Heated wire* for warming a wick or hollow fiber
Question 28 What are *five factors *associated with *condensation (rain out) in ventilator circuit?*
-*Temperature* difference between *humidifier and airway* -The *ambient temperature * -The *gas flow* -the *set airway temperature* -*Length, diameter and thermal mass of breathing circuit*
Explain the basic operation of the wick and membrane heated humidifier Membrane
-A membrane type humidifier separates the membrane from the gas stream by means of a hydrophobic membrane water vapor molecules can easily pass through the membrane but liquid water cannot -Advantages include: can maintain saturation at high flow rates Add little or no flow resistance to spontaneous breathing circuits Do not generate any aerosol / little risk of spreading infection
Retinopathy of prematurity (ROP) or Retrolental Fibroplasia
-Abnormal eye problem occurring in some premature or low birth weight infants -Excessive PaO2 levels causes retinal vasoconstriction Leads to necrosis of blood vessels New vessels form and increase in number Hemorrhage of the new vessels causes scarring behind the eye's retina, leads to retinal detatchment -affects newnates up to about 1 month -other associated problems are hypercapnia, hypocapnia, hemorrhage, infection and anemia hypothermia
The resistance across an HME can increase with?
-Absorption of water -Secretion contamination
cross contamination
-Aerosol and condensate from ventilator circuits are known sources of bacterial colonization -Wick and membrane type passover humidifiers prevent formation of bacteria carrying aerosols -Heated wire circuits reduce production and pooling of condensate -Higher temperatures in humidifiers is bacteriocidal -Circuit contamination usually occurs from patient to circuit
Define oxygen toxicity, its affects on the CNS and list precautions to avoid O2 toxicity.
-Affects the lungs and CNS -Pulmonary effects may occur at clinical PO2 levels -Oxygen toxicity CNS: Tremors, twitching, convulsions, symptoms are more pronounced with hyperbaric oxygen(usually aboe 1atm) -Avoiding oxygen toxicity: Limit patient exposure to 100% oxygen to less than 24 hours whenever possible. High FiO2 is acceptable if the concentration can be decreased to 70% within 2 days and 50% or less in 5 days
What effect does air dilution (air entrainment) have on aerosol output and aerosol density?
-Air dilution increases the aerosol output(total water leaving) but decreases the aerosol density(how thick it is) -Jet flow is not increased, large particles carried out by increased air entrainment flow -Aerosol density or amount of aerosol per liter of gas actually decreased with air entrainment -Aerosol output: 1 - 1.5ml/min -Particle size 55% fall into 1-5 micron range and 100% fall into 1- 10 micron range
Question #9 level ANSI set the minimum water vapor content to avoid damage to the upper airway non intubated pt(normal airway)?
-American National Standard Institute(ANSI) id 10mg/L water vapor content as minimum level of absolute humidity avoid mucosal damage to upper airway
What are the problems associated with using high FIO2 settings on an LVN?
-At higher FIO2 settings the total flow may not be sufficient to meet patients inspiratory demand
Question # 10 clinical signs and symptoms of inadequate airway humidification?
-Atelectasis -Dry, nonproductive cough -increase airway resistance -increase infection -increase WOB -substernal pain, airway dryness -Thick, dehydrated secretion [A.D. 3I's S.T]
Question 30 What is an advantage of an automatic feed reservoir system?
-Automatic feed system avoid the need for constant checking and manual refilling of heated humidifiers
what sizes do the OAWs come in for adults?
-Berman large: 100 mm (Guedel 5) -Berman medium: 90 mm (Guedel 4) -Berman small: 80 mm (Guedel 3)
what sizes do the OAWs come in for children?
-Berman: lengths 40-80 mm -Guedel sizes 000-3
Bubble Humidifiers
-Breaks underwater gas stream into small bubbles -Commonly used with oronasal oxygen delivery devices -Can provide absolute humidity levels between 15 and 20 mg/L -Incorporate a pressure relief valve (pop-off)
Oxygen Toxicity and O2 therapy
-Breathing up to 50% for extended periods without major damage. We attempt to keep FiO2 less than the 60% -Weigh both FiO2 and exposure time in assessing risks of high PO2 -Goal should always be to use the lowest possible FIO2 compatible with tissue oxygenation -Never withhold supplemental O2 from hypoxic patient -Toxic effects of high FIO2 can be serious -Alternative is certain death due to tissue hypoxia
What are two problems associated with the use of enclosures? (mist tents andhoods)
-CO2 build up and heat retention -CO2 build up can be reduced by having sufficient flow of fresh gas circulating through device -Heat build up may be handled by High fresh gas flow and incorporation of separate cooling device (usually electric powered refrigeration unit
Respiratory Depression
-COPD patient breathing due to hypoxic drive(chronic hypercapnia) which is high CO2 high PaCO2 -central response to carbon dioxide is blunted and the primary stimulus to breath is due to hypoxemic stimulation to the peripheral chemoreceptors -High levels of oxygen may cause hypoventilation (or worse) -Maintain PaO2 between 50 and 65 mmHg on these patients Our normal goal is 60 mmHg -High flow device and low concentrations of oxygen ideal: low flow nasal canula -If you give a person with hypoxic drive O2 they may hyperventilate and stop breathing.
Depression of ventilation
-COPD patients with chronic hypercapnia tend to ventilate less when breathing moderate to high O2 concentrations Suppression of the hypoxic drive Response to high PCO2 is blunted Primary stimulus to breathe is hypoxemia sensed by peripheral chemoreceptors
What are 3 cons of using an HME?
-Can cause Increased Delivery Pressures -Must be removed during Aerosol Therapy -May increase or thicken secretions
What problems does condensate in a ventilator circuit pose for mechanically ventilated patient?
-Can impair gas flow through circuit May effect ventilator function -condensation may be aspirated by patient Circuits must be pointed to drain condensate away from patient Check often, excess condensate must be drained from circuit -Patients contaminate circuits within hours which becomes colonizes with bacteria and thus poses an infection risk -Breathing circuit condensate should be treated as infectious waste
Minimizing Cardiopulmonary workload
-Cardiopulmonary systems compensates for hypoxemia by increasing: Ventilation and cardiac output -Hypoxemic patients breathing room air can only achive acceptable PaO2 by increasing ventilation -Increased ventilatory demand -Increased WOB -O2 therapy decreases ventilatory demand and WOB
Which type of Humidifiers delivers 100% BH?
-Cascade Humidifier -Wick Humidifier
Bland Aerosol Therapy
-Consists of liquid particles suspended in a gas
Low flow system
-Criteria Should have ventilatory pattern that is consistent and regular Should have tidal vol in 300 to 700 ml range Should have respiratory rate that is less than 25 breaths/min -Assessment of patient Therapist assessment Laboratory measurements Patients subjective response
Oxygen Toxicity Exudative phase
-Damage to alveoli and blood vessels with influx of inflammatory cells into interstitium -Low V/Q ratios -Physiological shunting -Hypoxemia -End stage Hyaline membranes form: cellualr debris and condensed plasma preteins that fill the alveolar spaces Pulmonary fibrosis Hypertension
Non rebreathing mask
-Delivers 80-95% at flow of 6-15L/min -flow must be sufficient to keep reservoir bag 2/3 full at peak inspiration -One way filter valve between mask and reservoir bag, which will not allow exhaled gases into the bag. -1 to 2 one way flutter valves are located on exhalation ports of mask to prevent room air entrainment. -Commonly used for severe hypoxemia ex: CO poisoning -used in hospital
Classify large volume nebulizers (type of flow) and define their use
-Device of choice to use with patients with artificial airways Tacheostomy collar and briggs T adaptor -Performs as a fixed performance device only when output flow meets or exceeds patients inspiratory demand. Fixed only if delivering low O2 concentrations of less than 28-100% -Do not allow easy increases in nebulizer output flow by means of an increase in O2 input. -6-15 L/min at 50 psig
What are the two major devices used to deliver a bland aerosol?
-Devices to deliver bland aerosol theapy are usually either large volume nebulizers (LVN) or untrasonic nebulizer (USN) -Delivery system includes: aerosol mask, face tent, trach collar, T - tube and mist tent
Bubble diffusion humidifiers
-Direct a stream of gas under water where it is broken up into tiny bubbles. The smaller the bubble the greater the water/air surface ration
Air entrainment system
-Direct high pressure oxygen source through a small nozzle or jet surrounded by air entrainment points. -Entrainment of air varies directly with port size. size - larger intake, more air entrained. velocity of oxygen - more air entrained. -Set to deliver less than 35% O2 easily meets peak inspiratory flow -above 35% difficult to main flow (FiO2 often variable) -Range 24-55% -Always provide less than 100% -More air entrained, higher total output flow, lower the delivered FiO2 -high flows only possible when deliverying low oxygen concentration -Function as true high flow system as low FiO2
Simple reservoir
-Directs gas over a surface of a volume of water -Limited surface area -Used with heater for mechanical ventilation -Used with room temperature fluid for nasal CPAP and BiPAP -Ex: air moving across a pan of water / boiler radiator heat
Humidifiers / Passover
-Directs gas over a water surface -Three common types: simple reservoir, wick and membrane
List indications for oxygen therapy
-Documented hypoxemia as evidenced by: PaO2 less than 60 mmHg or SaO2 less than 90% in subjects breathing room air. PaO2 or SaO2 below desirable range for a specific clinical situation -Acute care situations in which hypoxemia is suspected -Severe trauma -Acute myocardial infarction -Short term therapy or surgical intervention
mechanism of action for hydrophobic condenser
-During exhalation, the condenser temperature rises to about 25° C -On inspiration, cool gas and evaporation cools the condenser down to 10° C
What is a Hi-Lo EVAC tube?
-ETT with small opening above cuff that allows continuous suctioning of secretions above the cuff -lessens risk of aspiration -reduces occurence of VAP -most effective among pts expected to require >72hrs of mech ventilation
Ultrasonic Nebulizer
-Electrically powered -Use a Piezoelectric Crystal to generate an aerosol -Vibrations are transmitted to a liquid surface where the mechanical energy creates the aerosol droplets -Can produce aerosols with densities as high as 500 mg/L
Absorption atelectasis
-FIO2 increases 0.50 (60%) percent significant risk -O2 washes out the Nitrogen (N2) causing alveolar volume to decrease (N2 is thelargest amount of gas in alveoli and blood) Nitrogen levels decrease thus total pressure of venous gases rapidly decrease. Other gases that exist at atmospheric pressue within any body cavity rapidly diffuse into the venous blood This includes diffusion of oxygen from the alveolar region into the blood Alveolar plug complicate the problem more causing gas pressure in the alveolus to progressively decrease until collapsed and this=shunt -Risk greatest in patients: Breathing with low tidal volume Sedation, surgical pain, CNS dysfunction
Protection against malicious software
-Firewall: filter the exchange of data between the internet and local networks -verify user identification, passwords and registered internet address -restricts certain communication -update security patches -install virus scanning program and update it -discriminate email files -refrain from downloading applications from unknown sources
Question 35 Why are ventilator circuits changes less often then they once were?
-Frequent circuit changes actually increase the risk of nosocomial pneumonia -Minimal infection risks with weekly circuit changes -Many institutions no longer change circuits unless they are visibly contaminated -Less frequent changes also provide cost savings
Explain the basic operation of a bubble humidifier
-Gas conducted below the surface of sterile water and allowed to bubble back up to the top diffuser causes the gas to be broken up into smaller bubbles Increased efficiency due to increase surface area for gas/water content -The goal is to raise the water vapor content of the gas to ambient levels -can provide absolute humidity of 15 - 20 mg/L -most common, to provide some humidity for patients with nasal cannula and oxygen masks -used when flow greater than 4L/min
Question #16 basic operation bubble diffuser humidifier
-Gas go below the surface water and allowed to bubble back up to the surface ~Diffuser cause gas to broken up small bubbles ~^efficency ^ area content gas/water -provide absolute humidity 15-20mg/L -most common type humidifier -simple O2 devices flow greater 4L/min -heated reservoir ^ humidity cause occulsion small bore tubing -goal rise water vapor content comfortable 4 pt (nasal cannula and O2 mask provide humidity)
Ultrasonic nebulizers
-Have been marketed as cool mist devices for use in home as humidifiers -There is some concern that the reservoirs can easily become contaminated and source of infection. should be cleaned regularly and reservoir disinfected every 6 days
Partial rebreathing mask
-High concentration but still low flow -Delivers 60-80% O2 at flow rates of 6-15L/min -Flowrate must be sufficient to keep reservoir bag at least 2/3 full at peak inspiratio -No valves on mask -First part of patients exhaled gas enters the reservoir bag which is high in O2 -Mixes with O2 in bag
What does the *moisture output* of an *HME* tend to *fall with?*
-High volumes and high rates of breathing -High inspiratory flows and FIO2 levels
Variable affecting FIO2 of low flow oxygen system: Increases FIO2
-Higher O2 input -mouth closed breathing -low inspiratory flow -low tidal volume -slow rate of breathing -small minute ventilation
primary indications for humidity therapy
-Humidify dry medical gases -Overcome the humidity deficit created when the upper airway is bypassed
What is the difference between humidity and aerosol?
-Humidity (cant see) is simply water in the gas phase -Bland aerosol (Can see) consists of liquid particles in a gas
*warmed,* humidifiers used treat:
-Hypothermia want increase core temp. -prevention of intraoperative hypothermia -exercise or cold induced bronchospasm
Warmed, humidified gases are used to treat?
-Hypothermic patient who requires an increase in core temperature -Prevention of intraoperative hypothermia -Patient with exercise or cold induced bronchospasm A scarf over the face and mouth may act as a crude heat moisture exchanger Remember when you had on that mask for infection control
If water content is kept constant and temperature is increased, what effect will this have of relative humidity? Explain why this is true
-If a gas is cooled the capacity to hold water vapor will decrease and relative humidity will lower -If gas is warmed the capacity to hold water vapor will increase and relative humidity must increase
Question 5 If water content is kept constant and temperature is increased, what effect will this have of relative humidity? Explain why this is true
-If a gas is cooled the capacity to hold water vapor will decrease and relative humidity will lower -If gas is warmed the capacity to hold water vapor will increase and relative humidity must increase
How is corrugated tubing used with large volume nebulizers
-If you add 50-150 ml(open reservoir) tubing to expiratory side of the T tube you can obtain a higher FiO2. -Humidity and Temperature combined produce particulate water to the airways. this will cause entrainment and cause lower FiO2. To fix you would need to drain the tube. Results in inaccurate FiO2
Describe reservoir devices
-Incorporate a mechanism to gather and store oxygen between patient breaths. -Draw on this reserve supply whenever their inspiratory flow exceeds the oxygen flow into the device. Air dilution is reduced. Generally provide higher FIO2s than low flow systems -3 types: Simple mask, partial rebreathing mask and nonrebreathing mask
What will a lack of O2 in arterial blood cause?
-Increased work of the heart. By correcting hypoxemia we can prevent or minimize the increased cardiopulmonary workload associated with responses to hypoxemia
Question #6 ISB, 4 ways make it shift deeper into the lung?
-Isothermic saturation boundary -5cm below the carina - 4 things make ISB shift deeper into the lungs: * ~breathe through your mouth instead of nose ~upper airway is bypassed ~min. ventilation higher normal ~breathe cold, dry air* [B.U.M.B]
Define and contrast low flow and high flow devices (including minimum and maximum flows) low flow
-Low flow systems: supplemental oxygen directly to the airway at flows of 8L/min or less(exception high flow n/c) -Total inspired volume or flow is not delivered by the apparatus it is mixed with room air. -Oxygen provided always diluted with room air. -Low and vairable FIO2: nasal cannula, nasal catheter, transtracheal catheter -All extremely variable and unpredictable(if hypoventilatioin you will get more, hyperventilating and you will get less
Gas flows affect the contact time
-Low flows increase contact time -High flows decrease contact time
Contrast low level FIO2 devices, moderate FIO2 devices and High FIO2 devices. Give a patient example for each level
-Low(<35%): Fixed= AEM, air entrainment nebulizer, blending system, isolette incubator(infact) Patient Ex:Patient who comes in who is in unstable condition and needs a low flow system. Variable: nasal cannula, nasal catheter, transtracheal catheter, Ex patient: home care patient who need long term therapy. Stable patient who needs low flow FIO2 -Moderate (35-60%) fixed: air entrainment nebulizer, blending system Patient example:Patient who an artificial airway Variable: simple mask, air entrainment nebulizer Patient example:simple mask, emergencies, short term therapy req moderate FIO2, mouth breathing patients req FIO2 -High ( greater than 60%): Fixed: Oxyhood (infant), blending system, Patient ex: Infant who needs supplemental oxygen variable: tent (child)partial, nonrebreathing patient ex: nonrebreathing, emergencies, short term needing high FIO2
Variable affecting FIO2 of low flow oxygen system: Decreases FIO2
-Lower O2 input -mouth open breathing -High inspiratory flow -high tidal volume -Fast rate of breathing -large minute ventilation
Aerosol drug therapy includes?
-MDI -DPI -Jet nebulizers both SVN and LVN -USN -Atomizers / nasal spray pumps -Vibrating mesh nebulizers
advantages of bubble humidifiers
-Maintain saturation at high flows -Add little or no flow resistance to spontaneous breathing circuits -Do not generate micro aerosol particles (Pose a minimal risk for spreading infection)
Troubleshooting AE systems
-Major problem assuring that the set FiO2 is actually delivered to the patient, few problems below 35% -Performance is affected by downstream resistance Results in inaccurate FiO2 If you Increased FiO2. If blocked patient will become air hungry and entrain more room air and the oxygen percentage may decrease
secondary indications for humidity therapy
-Managing hypothermia -Treating bronchospasm caused by cold air
Question 25 What is the difference between a manual control and a servo control on a heated humidifier
-Manuel control to allow a therapist to regulate heat delivery to humidifier Like a knob on the stove. Higher reference number greater amount of heat available -Servo control: automatically adjust temperature level via a probe close to the patients airway Like thermostat on your furnace
List malicious software and preventative measures: Trojan horse
-Masquerades as seemingly benign and legitimate program -If activated, may lay dormant in computer and then emerge and destroy or remodel unsuspecting host by erasing drive -Can allow someone to gain control over invaded computer from remote site -Not self replicating
List malicious software and preventative measures: spy ware
-May be legitimately installed to enhance network security -May be embedded in downloadable files or free software on the web The purpose can be data collection for marketing via "cookies" malicious subversion of the operation of computer May log all of users keystrokes stealing confidential information
Question 33 Explain the basic *operation* of a *heated wire circuit*
-Most use *dual controllers with two temp sensors* * One monitors the temp leaving the humidifier* * One monitors the temp near patients airway* The *controller regulates the temperature* between the humidifier and the patients airway There is less water use, less condensation, less need for drainage and less infection risk to patient or healthcare worker
Be prepared to recommend oxygen delivery device for specific patient scenarios
-Nasal cannula: good for patients who need to eat. -Simple mask: ambulatory -partial rebreathing mask: patients with moderate to severe hypoxemia -Non rebreather mask: patients with severe hypoxemia(CO poisoning) -Air entrainment(venturi mask): alert patient needing low to mod FiO2 -Aerosol mask with air entrainment nebulizer: when bypassing upper airway. -Oxygen hood: infants and newborns -Oxygen tents: primarily used on children for croup, epiglottitis and cystic fibrosis
Performance - Low flow systems
-Nasal low flow system oxygen concentration ranges Normal range 22% - 44%, max flow of .5L/min to 6L/min most common and most common and comfortable for patient 8L/min could be considered a comfortable flow for some and new high L/min nasal systems that may achieve 60% -FIO2 varies with the amount of air dilution amount of dilution is variable based on multiple factors -Impossible to determine exact O2 concentration
If the DOWN tube on a Bubble Humidifier becomes obstructed, what happens?
-No bubbling or alarm will occur -And the Compensated Flow Meter will read ZERO
Who should use high flow nasal cannula?
-Numerous chronic lung disease improve gas exchange or reduce work of breathing -pulmonary fibrosis -unable to tolerate traditional mask: claustrophobia, burns -Unable to tolerate NIPPV, Dementia, DNR, End stage -High flow oxygen therapy should be considered as an alternative for patients with respiratory insufficiency that so not respond adequately to traditional methods of administering oxygen prior to implementation of NPPV or intubation/ mechanical ventilation
List the hazards of oxygen therapy (including hypoxic drive)
-Oxygen toxicity -Depression from ventilation -Retinopathy of Prematurity -Absorption atelectasis -hypoxic drive
What are some problems associated with computer usage in hospital setting
-Password security -HIPAA
Oxygen Toxicity
-Patchy infiltrates (white areas on xray) -Major alveolar injury -Damages the capillary endothelium -Interstitial edema: (fluids build up in interstitial) Thickening of the alveolar capillary membrane Type I cells destroyed Type II cells proliferate
Question 23 What are the contraindications of HME?
-Patient with thick, excessive or bloody secretions. -Patients with tracheal damage -Patients with body temperature less than 32C -Patients with high spontaneous minute volumes (>than 10 L/min) -HME must be removed from breathing circuit when patient is receiving in line aerosol (drug) therapy On some devices gas flow can be bypassed from going thru HME material -Not recommended for infants since deadspace and weight on ventilator circuit may decrease effective ventilation
What are the contraindications of HME?
-Patient with thick, excessive or bloody secretions. -Patients with tracheal damage -Patients with body temperature less than 32C -Patients with high spontaneous minute volumes (>than 10 L/min) -HME must be removed from breathing circuit when patient is receiving in line aerosol (drug) therapy On some devices gas flow can be bypassed from going thru HME material -Not recommended for infants since deadspace and weight on ventilator circuit may decrease effective ventilation
Question 32 What is the purpose of using water traps in a ventilator circuit and where should they be placed?
-Place water traps in low points in circuit (both inspiratory and expiratory side) -Water traps should allow emptying without disrupting ventilation and not be prone to leaks -Maintaining circuit temperature with heated wire can help prevent the formation or rain out
What is the purpose of using water traps in a ventilator circuit and where should they be placed?
-Place water traps in low points in circuit (both inspiratory and expiratory side) -Water traps should allow emptying without disrupting ventilation and not be prone to leaks -Maintaining circuit temperature with heated wire can help prevent the formation or rain out
According to Eggan, what are the two primary indications for humidity therapy and two secondary indications for humidity theryapy
-Primary goal : Humidification of dry inspired medical gases and overcoming the humidity deficit created when the upper airway is bypassed. Secondary indication: managing hypothermia and treating bronchospasm caused by cold air
What are the primary and secondary goals associated with a large volume nebulizer (LVN)?
-Primary goal: To provide humidification to the respiratory tract either with patients having an artificial airway or with patients complaining of dryness while inspiring medical gas Typically used continuously -Secondary goal: To improve bronchial(clean airway) hygiene; usually with a heated aerosol Typically used intermittently; 10-15 min treatment QID reduce mucosal upper airway swelling usually with cool aerosol Typically following extubation of a patient who required an artificial airway
Indications for humidification
-Primary indications: Humidification of dry inspired medical gas overcoming the humidity deficit created when the upper airway is bypassed -Secondary indications: managing hypothermia, treating bronchospasm caused by cold air
Aerosol nebulizers:
-Spray water particles into a gas stream The higher the aerosol density( number of particles per volume of gas) the greater the surface area
Question 22 What are the *characteristics* of an *ideal HME?*
-Standard set by International Organization of Standards (ISO) -*Operate at 70% *efficiency or better -*Providing* at least *30mg/L water vapor* -Uses standard connections -Have a *low compliance* -*Add minimal weight* *-Add minimal dead space* *-add minimal flow resistance to a breathing circuit*
What solutions are delivered via a bland aerosol?
-Sterile water -Hypotonic Saline <(0.90)% ex: 0.45% -Isotonic Saline aka as normal saline(0.90)% -Hypertonic Saline >(0.90)% Ex: 7%
High Flow systems
-Supply oxygen concentration at flows equaling or exceeding the patients peak inspiratory flow. -Air entrainment or blending system -If flow delivered exceeds patient flow you can ensure a fixed FIO2 -To qualify for high flow device, a system should provide at least 60L/min of flow. The flow criterion is based on the fact that an average adult peak inspiratory flow during tidal ventilation is approximately 3x the minute volume.
Transtracheal Catheter
-Teflon catheter surgically inserted into the trachea. between 2nd and 3rd tracheal ring -No humidifier required -40 - 60% less O2 to achieve a given PaO2 low as .25L/min to achieve adequate oxygenation -cheaper, more mobile, smaller flow needed
Question #13 4 principles or variables that affect performance of humidifiers
-Temp -time contact -thermal mass -surface area
Question 34 When using a heated wire circuit with a neonate, where should the temperature probe be placed?
-Temp probes need to be placed outside of isolettes or radiant warmers
What are three factors that affect the performance of a humidifier?
-Temperature : increased T = increased Humidity -Surface area: Increased SA = increased humidity -Time of contact -thermal mass
What are five factors associated with condensation (rain out) in ventilator circuit?
-Temperature difference between humidifier and airway -The ambient temperature -The gas flow -the set airway temperature -Length, diameter and thermal mass of breathing circuit
If the alarm on a Bubble Humidifier sounds without an intentional occlusion, what is the cause?
-The gas flow is too HIGH -A kink in the tubing -Obstruction of the outlet
Explain how both of the above are affected by the patients breathing patterns
-The more the patient breathes, the more air dilutes the delivered O2, and FIO2 is lowered -If the patient breathes less with this type of device, less air dilutes the O2 and FIO2 increases. -A system that provides only a portion of the inspired gas always provides a variable FIO2
Heated humidifier systems
-Traditional recommendations has been to *keep the inspired gas 100% saturated at 37C* -Reasonable approach would seem to be to provide *100% relative humidity at temperatures between 32 -34C* -*Heat improves *the *water output of bubble and passover humidifiers* Used primarily for patients with *bypassed upper airways or mechanical ventilation*
advantages of using heat and moisture exchangers
-Use standard connections -Have a low compliance -Add minimal weight, dead space, and flow resistance to a breathing circuit
List malicious software and preventative measures:virus
-Viruses: May erase files, documents or render programs inoperable Self inflicted Attatch to email or downloaded from web
Contrast large volume nebulizers with oxygen blenders
-When large volume nebulizer cannot provide high enough O2 concentration or flow oxygen blender may be considered.You input seperate air and O2 and they are mixed. This system allows precise control over fio2 and output -Can provide flow greater than 60L/min so fixed delivery device. -Adults use aerosol mask or T tube like nebulizer or nonrebreathing system -Alarm if gas fails or pressure decreases. -especially prone to inacuracy and should be checked once per shift
List malicious software and preventative measures: worms
-Worms: self replicating malicious computer program. self contained User does not need to do anything. can spread to entire network Invade computer memory, distributes copies of itself to others
Question #14 Surface area effects the performance of humidifiers?
-^ area contact between water/gas and greater opportunity for evaporation to occur -most efficient designs. (B.A.W) bubble aerosol wick -most common method increase surface area gas through water form small bubbles
humidifiers
-add molecular water to gas -occurs by evaporation from water surface into gas
humidity therapy
-adding water vapor and sometimes heat to inspired gas -invisible moisture -water forms individual molecules in it vapor or gaseous state
How do you set up a heated high flow nasal cannula?
-adult flow set at 20-50LPM -ped/neo flow at 6-10LPM -diameter of cannula shouldn't exceed more than 1/2 the diameter of the patient's nares (may need to discontinue feedings and monitor for abdominal distension)
How do you assess the tube position?
-after inflating the cuff, ventilate the patient using a resuscitation bag and watch the chest wall for adequate and equal expansion -auscultate for equal bilateral breath sounds as the patient is being bagged. Look for condensation in ET tube -Auscultate stomach for air movement. if air is noted, the tube may be in the esophagus
how do you size a NAW?
-airway diameter should not be too large -length: tip of the nose to the tragus of the ear
what are the indications for a nasal airway (NAW)?
-airway maintenance -OAW placement difficult -semiconscious patient not tolerating OAW -nasotracheal intubation guide in maxillofacial trauma
how is the NAW specifically inserted into the nostril?
-along floor of nostril, perpendicular to face -parallel to turbinates
what is needed for negative-pressure ventilation?
-bag-mask ventilation -LMA -ETT
what is needed for positive-pressure ventilation?
-bag-mask ventilation -LMA -ETT
what are the 2 types of oral airways?
-berman -guedel
What are the immediate complications of a tracheostomy tube?
-bleeding- turn off heated humidification for 24hrs (heat draws blood to surgical site) -pneumothorax/air embolism: caused by tube itself or surgical incision; relatively rare and treated with chest tube -subq emphysema: air trapped under subq layer of skin, crackling feeling to touch, normally resolves itself
what are the structural similarities and differences between the types of OAW?
-body of Berman has a central beam and side air channels -body of Guedel has a central lumen -both have a flange
clinical examples of histotoxic hypoxia
-cyanide toxicity -increased TNF -late sepsis
how do you insert the LMA?
-grasp tube like a pen as near as possible to mask end -place tip of LMA against inner surface of pts upper teeth -keep neck flexed&head extended -press mask into pts mouth and up against hard palate using index finger -use index finger to advance tube, maintaining pressure on tube with finger *note position of wrist -advance mask until resistance is felt at base of hypopharynx -grasp tube firmly with other hand and remove finger -press gently down with your other hand to ensure mask seals over airway -inflate mask to recommended volume -don't touch LMA while it's inflating -check proper insertion using same techniques as ET tube
What is a cascade humidifier?
-has a heated grid that water passes through and creates many bubbles -capable of providing high heat and humidification output 100% -problems involve keep water bath filled and rainout in tubing
Administer a dry medical gas at flows greater than 4L/min cause?
-heat and water loss -prolonged exposure cause damage to epithelial lining - exposure to cold, dry gas cause ciliary activity decease, airway become irritable, increase in mucus production, pulmonary secretion become inspissated.
Question #7 primary indication for humidification
-humidification of dry inspired medical gas -overcoming humidity deficit when upper airway is bypassed
classifications of hypoxia
-hypoxic hypoxia -circulatory hypoxia -hemic hypoxia -demand hypoxia -histotoxic hypoxia
what are the contraindications for HME use?
-increased secretions -thick, dehydrated secretions -hypothermia -during aerosol therapy (MDI/neb) -min ventilation > 10L/min and/or Tv> 1000ml -during heated humidification
physical maneuvers for supporting the airway
-jaw thrust -chin lift
What is tracheal stenosis?
-narrowing of trachea that develops from chronic inflammation, fibrosis, and necrosis, which causes scarring and stricture within the trachea -occurs at site of the tracheostomy tube cuff due to high pressures that exceed tissue perfusion pressure -can occur at stoma site and attributed to excessive traction on the trach tube from ventilator tubing tension or movement of loosely secured tubes
6 common oxygen delivery devices and systems
-nasal cannula -simple face mask -mask with reservoir -partial rebreathing mask-bag -nonrebreathing mask-bag -venturi mask and jet nebulizer
characteristics of anesthesia face masks
-opaque or transparent body -22 mm connection -air-filled seal -retaining ring
adjuncts for physical support of the airway
-oral airway (OAW) -nasal airway (NAW)
what are complications of an oral airway?
-oral airway too long -oral airway too short -vomiting and laryngospasm in the awake patient
what are the potential passageways for releiving airway obstruction?
-oral route -nasal route
Large-Volume Jet Nebulizer
-pneumatically powered (attaches directly to flowmeter) -Liquid particle are generated by passing gas at a high velocity through a small "jet" orifice
what are low flow humidifiers?
-used with low flow O2 devices -limited amt of humidity provided -patients on low flow O2 devices entrain room air so the humidifier is only partially providing humidification
What is a wick humidifier?
-uses cylindrical shaped absorbent paper or sponge that draws up water from a reservoir using capillary action -gas passing through picks up water vapor that evaporates from the wick -usually heated which increases humidity produced -can produce 37C and 44mg/L output
what are heated wire circuits?
-virtually eliminates condensation in the circuit -the gas temp can be maintained throughout the wire this way
Question 4 What is the normal value for water vapor pressure in mmHg or torr if a gas is 100% saturated at body temperature?
...
What size of microns can enter alveoli
.5-2 microns
FIO2 range of a nasal cannula with a flow rate of 1 L/min
0.21-0.24
FIO2 range of a nasal cannula with a flow rate of 2 L/min
0.23-0.28
FIO2 of a venturi mask and jet nebulizer with a flow rate of 4-6 L/min and total flow of 15
0.24
FIO2 range of a nasal cannula with a flow rate of 3 L/min
0.27-0.34
FIO2 of a venturi mask and jet nebulizer with a flow rate of 4-6 L/min and total flow of 45
0.28
FIO2 range of a simple mask with a flow rate of 5-6 L/min
0.30-0.45
FIO2 range of a nasal cannula with a flow rate of 4 L/min
0.31-0.38
FIO2 range of a nasal cannula with a flow rate of 5-6 L/min
0.32-0.44
FIO2 of a venturi mask and jet nebulizer with a flow rate of 8-10 L/min and total flow of 45
0.35
FIO2 range of a mask with reservoir
0.35-0.50
FIO2 range of a partial rebreathing mask-bag with a flow rate of 7 L/min
0.35-0.75
FIO2 of a venturi mask and jet nebulizer with a flow rate of 8-10 L/min and total flow of 33
0.40
List six factors that can affect the performance of a SVN.
1) nebulizer design 2) gas pressure 3) gas density 4) temperature 5) humidity 6) medication characteristics
Name 4 types of heating devices that can be used to increase the humidity output of an active humidifier.
1) simple HME's 2) heat and moisture exchanging filters 3) hygroscopic condenser humidifiers 4) hygroscopic condensers w/filters
Name two types of commercially available threshold resistors that are used to administer CPAP.
1) underwater seals 2) weighted ball receptors
IS is indicated for patients who are predisposed to develop atelectasis. List four medical conditions for which IS is indicated.
1) upper abdominal surgery 2) thoracic surgery 3) presence of restrictive lung defect associated with quadriplegia or a dysfunctional diaphragm 4) to prevent atelectasis in patients with COPD who are scheduled for surgery
Indications for Humidfication therapy
1)Humidfying dry medical gasses 2) Overcoming the humidity deficit created when the upper airway is bypassed 3) Managing hypotermia 4) Treating bronco spasm from cold air
output of USN
1-6 cc per min
Ultrasonic Nebulizers (USN) Components include: 1. __________ 2. __________ 3. __________ 4. __________ 5. __________ 6. __________ 7. __________
1. A radio frequency generator 2. A Shielded cable 3. A Reservoir chamber 4. A Fan 5. A couplant chamber 6. A chamber for normal saline or distilled water to be nebulized 7. A Piezoelectric crystal/transducer
Key facts and concepts about humidification systems
1. All modern humidifiers saturate the gas passing through them (achieve 100% relative humidity) 2. Actual water vapor content (absolute humidity) delivered to the patient depends on a. the humidifier's operating temperature (the higher the temperature, the greater the absolute humidity) b. whether the gas leaving the humidifier warms, cools, or remains at the same temperature 3. Condensation in the delivery system occurs only if the gas leaving in the humidifier cools on the way to the patient.
Advantages of Polarographic Analyzers
1. Also provides a continuous reading of FIO2. 2. Can also be used to analyze gas that is in motion. 3. Has an additional power source, therefore response time is faster. 4. The fuel cells last longer because the analyzer can be turned off, stopping the chemical reaction, between uses.
Problems encountered in Transcutaneous Monitor include:
1. Burning of electrode sites. Typically, the electrode is moved every 4 to 6 hours to prevent this complication. 2. Inaccurate readings in poor perfused states.
Components of a MDI (Metered Dose Inhalers)
1. Canister 2. Propellant 3. Mouthpiece 4. Spacer (optional, but generally used in a hospital setting)
Three common problems arise as the result of heating and humidifying inspired gases
1. Condensation 2. Cross contamination 3. Proper conditioning of inspired gas
What are three drawbacks to bland aerosol therapy?
1. Cross-contamination/infection 2. Environmental exposure 3. Inadequate mist production
What are the different probes used for the pulse oximeters?
1. Ear probes 2. Finger/Toe probes 3. Nose probes 4. Forehead probes
Pulse Oximeters: Clinical applications include:
1. Exercise studies 2. Sleep apnea studies 3. Initial evaluations 4. Continuous monitoring 5. Titration of oxygen therapy 6. Monitoring during transports
A two-point calibration for oxygen analyzer, at 21% and 100%, is performed:
1. Expose the analyzer to room air. 2. Adjust the calibration to read 21% 3. Expose the analyzer to a 100% oxygen environment. a. Calibration is typically done by placing the electrode inside an exam glove and flooding the glove with oxygen. b. The oxygen source should be a wall outlet or a cylinder of oxygen. A blender is not an appropriate source as the blender itself may be inaccurate. 4. Adjust the calibration to read 100% 5. Repeat the procedure until a stable reading at both points is obtained without adjustments.
Wick humidifiers consists of:
1. Gas inlet 2. Gas outlet 3. Reservoir 4. Disposable wick, usually made of very absorbent paper. 5. Heating element 6. Continuous water feed connection.
Aerosol Therapy Standard Precautions: 1. __________ 2. __________ 3. __________
1. Handwashing, of course. 2. Gloves when dealing with liquids. 3. Masks if the patient has a communicable pulmonary infection.
Aerosol Therapy Contraindications: 1. ___________ 2. ___________
1. History of reactive airway disease. 2. Fluid overload
Ultrasonic Nebulizers (USN) This tap water serves two functions:
1. It completes an electrical circuit 2. It cools the piezoelectric crystal.
Why is the wick humidifier popular?
1. It is very efficient, with minimal deadspace. 2. It is easy to clean and sterilize. 3. Because so little water is in the reservoir, temperature can be adjusted quickly.
Insertion of NAW?
1. Lubricate with water soluble lubricant of anesthetic jelly 2. Gently insert into nostril (straight down) 3. Check for respirations following placement
How to bag-mask ventilate
1. Mask is pressed against nasal bridge w/thumb 2. Index finger exerts downward pressure on base of the mask over the chin 3. Little finger should engage the angle of the mandible
Do not function well in the presence of: 1. High ____________ volumes. 2. ________ body temperature. 3. The presence of large amounts of ________ ____________.
1. Minute 2. Low 3. secretion
Ultrasonic Nebulizers (USN) Hazards of USNs
1. Nosocomial Infections 2. Electrical shock hazards 3. Bronchospasm
Disadvantages Polarographic Analyzers .
1. Obstruction of the membrane, as with aerosol droplets, can cause an erroneous reading. 2. The fuel cell must be replaced periodically replaced.
What are the disadvantages of the Galvanic O2 Analyzers?
1. Once the fuel cell is activated the chemical reaction continues until the electrolyte is exhausted. (It cannot be shutoff) 2. Because chemicals in the fuel cell are continuously being used the fuel cell must be replaced periodically. 3. Obstruction of the membrane, such as with aerosol droplets, will cause an error in the reading. 4. Readings may be affected by high pressures.
HMEs are popular because they: 1. Decrease provider exposure to ________ since there is no liquid water. 2. Allow for longer use of ___________ circuits since these do not get wet when HMEs are used. 3. Are more ____________ than a traditional heater and water humidification system. 4. May be used to provide humidity for patients with _________ _________ _________.
1. Organisms 2. ventilator circuits 3. economical 4. permanent artificial airways
What are the types of humidifiers?
1. Pass-over Humidifier 2. Bubble Humidifier 3. Wick Humidifier
Aerosol Therapy Indications:
1. Presence of an artificial airway 2. Need to deliver medications 3. Need to obtain sputum specimens or mobilize secretions. 4. Hypothermia (heated aerosol) 5. Upper airway edema (cool aerosol)
What are the advantages of the Galvanic O2 Analyzers?
1. Provides a continuous reading of FIO2. 2. Can be used to analyze samples of moving gas.
What are the 3 kinds of patients (breathing wise)?
1. Pt that breaths spontaneously 2.attempting to breath but inadequate 3. paralyzed (not breathing)
Obstructed airways can be relived by?
1. Repositioning head 2. Displacing the mandible anteriorly
Bubble humidifiers consists of:
1. Reservoir 2. DISS gas inlet 3. Gas outlet 4. Diffusing element 5. A pressure relief valve
The pass-over humidifiers consists of:
1. Reservoir 2. Gas inlet 3. Gas outlet 4. May include a float for a continuous feed system
What are two types of Passover devices?
1. Simple reservoir type 2. Wick type: has an absorbent material that increases the surface area for dry air to interface with heated water.
Jet Nebulizer: Baffles can be any obstruction in the path of the gas flow and include, but are not limited to:
1. Structures intentionally placed in the path of the gas flow. 2. The walls of the tubing. 3. Bends in the tubing. 4. The walls of the reservoir chamber.
What are the factors that affect humidity?
1. Temperature 2. Surface of area in contact with gas. 3. Time in contact of the reservoir and gas.
What are the 2 reasons why the efficiency of the bubble humidifier decreases?
1. Temperature decreases. Therefore, the carrying capacity of the gas decreases as well 2. Reservoir decreases in size as well as the time and contact of the gas.
What are the indications of Humidity Therapy?
1. The inhalation of significant amounts of dry gas. 2. The presence of an actual or potential humidity deficit.
The amount of water vapor added from a humidifier is dependent upon:
1. The temperature of the gas and liquid. The warmer the gas, the more water may be carried as a vapor. Colder gas carries less water vapor than warm gas. 2. The Surface Area in contact with the water. Increasing the surface area for contact will increase the humidity. Decreasing the surface area for contact will decrease the humidity. 3. The amount of time the gas is in contact with the water. Increasing the amount of time the gas is in contact with the water will increase humidity. Decreasing the amount of time the gas is in contact with the water will decrease humidity.
The clinical applications for the capnograph includes:
1. Titration of mechanical ventilation. 2. Identification of some disease states (particularly new pulmonary embolism). 3. An elevated baseline may indicate rebreathing of exhaled gases. 4. Correct placement of an artificial airway. 5. The effectiveness of CPR.
Two systems of humidification for warming and humidifying gases delivered to mechanically ventilated patients.
1. active humidification through a heated humidifier (HH) 2. passive humidification through a heat and moisture exchanger (HME)
What are the uses of an ETT?
1. airway of choice in an emergency 2. access for suctioning lower airways 3. connection for mechanical ventilation 4. protects airway from aspiration 5. allows for direct instillation of meds
What are the advantages of a nasopharyngeal airway?
1. better tolerated&more comfortable in semi-conscious pts 2. eliminates the risk of trauma to tongue&teeth 3. may be used to aid a bronchoscopy
What is a Berman oropharyngeal?
1. flange at oral end 2. rigid support beam through center 3. open sides which allow for air passage and access for suctioning
what are the indications of a nasopharyngeal airway?
1. for conscious pts 2. relieves obstruction caused by the tongue 3. easy access to trachea for nasotracheal suctioning 4. protect nasopharyngeal mucosa from trauma that can occur during suctioning
What are the steps for a needle cricothyrotomy?
1. identify cricothyroid membrane 2. pierce at 45 angle 3. place catheter or stylette 4. advance dilator per manufacturer's recommendation
In patients with acute respiratory failure, HMEs substantially
1. increased minute ventilation 2. increased ventilatory drive 3. increased work of breathing.
What are the advantages of an LMA?
1. insertion is simple 2. provides patent airway that is usually superior to that from an oral or nasopharyngeal airway 3. doesn't require any manipulation or extreme head positioning
what are the components of a LMA?
1. large bore tube 2. small, inflatable mask 3. pilot line and balloon with 1-way valve 4. 15mm adaptor at proximal end
what is a Guedel oropharyngeal airway?
1. large flange at oral end with supportive bite 2. body is semi-rigid 3. center of body is open for air passage and suctioning
how do you insert a nasopharyngeal airway?
1. lubricate tip with water soluble lubricant 2. insert slowly into nare 3. tip should be visible just below uvula 4. remove& clean every 24hrs. re insert in opp nare if possible
how is a NAW inserted?
1. lubricated with water soluble lubricant/anesthetic jelly 2. insert into nostril 3. check for respirations following placement
what are the problems of an oropharyngeal airway?
1. stimulation of gag reflex in alert patient may cause vomiting and possible aspiration 2. laryngospasm 3. incorrect placement may allow tongue to obsstruct airway
What are the factors that can affect the output of a humidifier?
1. temp: increased temp increases the amt of H2O vapor it can hold 2.Surface Area: greater the area of contact b/n water and gas, the more evaporation can occur 3. Contact time: longer a gas remains in contact with water the more evaporation can occur
What are the indications to use an artificial airway?
1. to prevent or relieve upper airway obstruction 2. to protect airway from aspiration 3.provide access for suctioning 4. provide connection for mechanical ventilation
What do you do if the laryngoscope light doesn't illuminate?
1. unlock and disconnect and reconnect hangle 2. tighten bulb and battery door 3. change batteries 4. change bulb
on inspiration cool gas and evaporation cools the condenser down to
10 degrees celsius
unheated humidifiers can be up to ? degrees below ambient temp
10 degrees celsius
How long of a tx with a SVN?
10 min with 3-5 cc
How much percent of medications for a SVN reaches the lower airways
10%
Amount of flow needed for nonrebreathing mask?
10-15 L/min
flow rate and O2 percentage with a non rebreathing face mask
10-15 L/min; up to 100%
An unheated bubble humidifier can provide what absolute humidity level?
10-20 mgh20/L
A gas must be ______% RH before it will carry an aerosol.
100%
A gas must have a RH of _____% before it will carry aerosol particles of water.
100%
What percentage represents air being fully saturated?
100%
Additional reservoir from a face mask?
100-200 mL
Jet Nebulizer: A Continuous Medication Nebulizer (a HART or HOPE nebulizer), is one with a reservoir which holds _____ to _____ cc of liquid.
100; 200
Mucus production in a day is?
100ml
Continuous Med Nebulizers: A mini-hart is ___ ml. and gives ___ hour(s) to ___ hour(s) neb treatment.
10; 1; 4
What level has ANSI set as the minimum water vapor content to avoid damage to the upper airway in non intubated patients (those with normal upper airways)?
10mg/L
Unheated humidifiers can be as much as
10° C below ambient temperature
bubble humidifiers can provide absolute humidity levels between
15 and 20 mg/L
calculate the patient's inspiratory demand. Tidal volume 500cc, RR 12, I:E 1:2
18 LPM
When was the Laryngeal mask airway first introduced?
1992
Describe the assessment tools and bedside skill needed to assess the need for oxygen therapy
1st- laboratory measures of hypoxemia: draw blood, saturation monitoring 2nd- Specific clinical problems or conditions 3rd- Manifestations of hypoxemia: Tachypnea, cyanosis, overall appearance and distress 4th-Bedside assessment: SpO2
Air Oxygen Blender needs ___ gas sources.
2
All analyzers require a ___ point calibration.
2 point
Non-Heated Cascade/Diffuser Humidifiers pop-offs are set at?
2 psi
How long of a tx is it for using an USN
20 min
how long does an ultrasonic treatment last?
20 minutes
Continuous Med Nebulizers uses equal or greater than ____ ml.
200
A COPD patient produces how much mucus during an exacerbation?
200-300ml/day
The required 2 pt. calibration for Oxygen Analyzers are _____% for room air and _____% to fill a plastic bag from an O2 flow meter and stick the sensor in.
21%; 100%
What is the Temp, RH and, AH in mouth
22 degrees, 50%, and 10 mg/L
How long are HME generally used?
24-48 hours
Venturi mask FIO2 values?
24-50%
with a hydrophobic condenser, during exhalation, the condenser temp rises to about
25 degrees C
What is the airway cuff perfusion pressure supposed to be?
25mmHg
unheated LVJN has total output
26-35
Unheated LVJN has total output between
26-35 mg H2O/L
The pressure relief valve is typically set to sound with very small (< _____ cm H2O) increases in pressure. The most common cause of this alarm is __________ or ___________ of the oxygen supply tubing.
2; crimping or kinking
The dense mist in Ultrasonic Nebulizers (USN) is ~ ___ µ in size.
3
Ultrasonic Nebulizers (USN) Use high frequency sound waves to produce a fine aerosol with the majority of particles in the range of ______ µ.
3
how does the oxygen percentage in a nasal cannula change?
3% for the first L/min of O2 with a 4% increase every L/min after that
Jet Nebulizer: A Small Volume Nebulizer (SVN), also called a Hand Held Nebulizer (HHN), is one with a reservoir volume of < _____ ml.
30
Jet Nebulizer: Small Volume Nebs (SVN) <___ ml
30
What is the Temp, RH and, AH in hypopharynx
30 degrees, 95%, 30 mg/L
Question 19 What level has ANSI set as the minimum water vapor content to avoid damage to the upper airway in intubated patients?
30 mg/L
Question 27 According to ANSI, what is the minimum absolute humidity level for intubated patients?
30 mg/L - temperature 33C
Flow amount of high pressure flow devices
30-40 L/m (4x's minute volume)
find the total flow output for a patient on an AFM 40% Fio2 @ 8 LPM
32 LPM
heated LVJN has a total output between
33 and 55 mg H2O/L
heated LVJN has total output
33-55
2012 AARC guidelines say?
34-41C and 33-44mg/L
Question 31 What *temperature range* should be used for *heated humidifier?*
35-37C
At the alveolar level, under normal atmospheric pressure conditions, the temperature of the gas is at ____o C, and completely saturated with water vapor.
37 C
What temperature is inspired air when it reaches the lungs?
37 c or 98.6
What is the Temp, RH and, AH in carina
37 degrees, 100%, AH 43.9
Ideally inspired gas should be heated and humidified to?
37C and 44mg/L (aka BH)
Jet Nebulizer: Continuous Medication Nebulizer (a HART or HOPE nebulizer) are specially designed to produce a majority of particles in the ___ to ___ µ range.
3; 5
What gas flow do you use for a humidifier ?
4 L/m
Transcutaneous Monitor: The skin under the electrode is heated to between ______ C and _______ C.
43 C; 44 C
at 37 degrees Celsius and 100% saturation, gas holds ____ mg/L of gas
44
What is the water vapor pressure and how many liters of gas is held at 37 degrees?
44 mg H2O/L and 47 mmHg
How much water per liter of gas can air hold at 37 degrees Celcius?
44 mg/H2O
At 37C and 100% saturation gas holds
44 mg/L
How much water vapor is present at 37 degrees Celsius and 47 mm Hg of pressure?
44 mg/L
What is normal water vapor pressure (content) ?
44 mg/L
What is the capacity of water at body temperature?
44 mg/L
What is the specific humidity once it is pass the carina?
44 mg/L
What is the total required moisture input?
44 mg/L
At BTPS conditions, gas can carry a maximum of ____ mg/L of water vapor, which exerts a partial pressure of water vapor (PH2O) of ____ mm Hg.
44 mg/L; 47 mm Hg
How do you calculated HD?
44-water content=HD
Question 3 What is the normal value for water vapor content in mmHg or torr if a gas is 100% saturated at body temperature?
44mg/L / 44mg/L = 1 x 100 = 100%
at 37 degrees Celsius and 100% saturation, the partial pressure will be ____ mmHg or torr
47
normal vapor pressure at body temp is?
47 mm
If inspired air is saturated at 100% at 37 degrees Celcius, how much water vapor pressure is being exerted?
47 mm Hg
What is the pressure of water vapor?
47 mm Hg
normal vapor pressure at body temperature is
47 mmHg
the partial pressure at 37C and 100% saturation is
47mm or torr
The maximum FIO2 for Large Volume Nebulizer (LVN) is ____%.
50%
Require a ___-psig source for oxygen and a ___-psig source for air.
50-psig; 50-psig
Jet Nebulizer: A Large Volume Nebulizer (LVN) can use greater than _____ ml.
500
Jet Nebulizer: A Large Volume Nebulizer is one with a reservoir volume of > ______ cc.
500
ultrasonic nebs can produce aerosols with densities as high as
500 mg/L
BTPS is located
5cm above the carina called the isothermic saturation boundary (ISB)
Jet Nebulizer: Small Volume Nebulizer (SVN) generally require a gas flowrate of ___ - ___ lpm to function properly.
6 - 10 LPM
flow rate and O2 percentage with a simple face mask
6-12 L/min; 35-60%
flow rate and O2 percentage with a partial rebreathing face mask
6-12 L/min; 60-90%
adults size small NAW:
6-7 mm internal diameter, 28 fr
coming out of the flow meter at flush is ___ LPM
60
Coming out of a flow meter at flush is
60 LPM
What percent of humidity at BTPS must be maintained to prevent cell damage?
60%
FIO2 for partial rebreathing mask?
60-80+
Additional reservoir from a partial rebreathing mask?
600-1000 mL
Bubble humidifiers generally uses flows less than or equal to ______ LPM.
7
If you have a flow rate to 10 LPM going to a bubble humidifier, what is the flow rate are patients getting? Why?
7 LPM. Because bubble humidifiers are designed to use ≤7 LPM and the excess flow goes out of the pressure relief valves in the bubble humidifier due to back pressure.
flow rate range of a nonrebreathing mask-bag
7-15 L/min
adult size medium NAW:
7-8 mm internal diameter, 30 fr
hygroscopic needs to operate at about ? efficiency rate
70 % efficiency rate
use a jet intermittent at __ LPM?
8
what LPM do you give a breathing treatment
8
adult size large NAW:
8-9 mm internal diameter, 34 fr
Normal airway humidification.....
80-90% saturated with water
What is hypertonic NaCl solution?
<0.9%
What is percentage Hypertonic NaCl solution?
>0.9% (10% normally)
What size particles are prevented from entering the lower respiratory tract
>5 microns
A popular type of humidifier for use with ___________.
?
Advantages of MDI over SVN 1. More _______ effective 2. More _______________ for the patients 3. Less ____________ Intensive 4. Patient __________
?
Advantages of MDI over SVN Patients can be taught proper use of the MDI prior to discharge from the acute hospital. They can be monitored for several days, verifying their understanding of the technique. In addition, this allows time for the patient to ask questions. These sessions have been shown to result in better patient understanding, use, and compliance than trying to do a quick 10 minute teaching session just before the patient is discharged.
?
Aerosol Therapy Possible Complications: Thermal damage to the airway Prevention/Action: Place a thermometer in-line to monitor temperature. Unless the indication for aerosol therapy is hypothermia, keep the delivered temperature < _____o C. This is only a concern if using a heated aerosol.
?
The _________ of the water column affects the ________ the gas is in contact with the water.
?
The wick provides a greater ____________ ________ for the gas and water to interface.
?
How is Relative Humidity measured by?
A Hygrometer
What does a HME booster consist of mechanically?
A T-piece containing electrically heated element
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A computer based interactive discussion group: chat room, aol instant messenger, share ideas
What is a humidifier?
A device that adds molecular H2O to gas, occurring by evaporation of H2O from a surface.
Nebulizers
A device which produces an aerosol and uses a baffle
Aerosol
A suspension of liquid or solid particles in a gas
Aerosol is....
A suspension of liquid or solid particles in gas (pollen, spores, dust)
End-Tidal used mostly as a "trend" value and must be correlated with an ___
ABG
What are the effects of inserting an artificial airway?
AH is less than BH ISB is shifted down the RT Humidity comes from lower RT Increased heat and moisture loss from the airways
The actual conent or weight of water present in a given volume of gas, is termed?
Absolute Humidity
What does a Humid-Heat HME do?
Absorbs expired heat and moisture, then releases it into inspired gas.
Pulse oximeters are _________ only if the patient heart rate matches the heart rate displayed.
Accurate
Oxygen is a drug, and as such, must be measured ___________.
Accurately
Question 26 What is the difference between an active and passive HME?
Active: External heat and water can be added to the HME Water pump to add water directly and electric heater to evaporate water into inspired air -The goal is to reach 100% body humidity at 37C -should compare favorably with heated wich and membrane systems -Possible advantages is less condensation "rainout" in ventilator circuit -Possible disadvantage is weight, complexity of system and cost
What is absolute humidity ?
Actual amount of water in air
Absolute humidity
Actual content of water in a measured volume of a gas
Absolute humidity
Actual content of water in a measured volume of a gas 10 mg/L
What is humidity ?
Addition of water to gas delivered to airway
Prior to use, oxygen analyzers must be checked for _________ functioning.
Adequate
What is the advantage and the disadvantage of the Galvanic O2 Analyzer?
Advantage: It gives a continuous reading Disadvantage: It cannot be turned off
Describe the advantage and disadvantage of high flow nasal cannulas
Advantages: Comfortable delivery, can eat and drink and talk, broad range of flows and O2 concentrations (flexible as patient condition changes), Improved respiratory efficiency, better secretion clearance, alternative for comfort end stage, less changing between multiple oxygen devices, increase confidence in the actual FiO2 being delivered to patient, used to wean patients for noninvasive or invasive ventilation Disadvantages: Drying and damaging to mucosa( high flows uncomfortable for the patient. some systems are not heated although provide humidification.) Some systems not able to achieve liter flows greater than 15 L/min, cost, physician buy in
Advantages and disadvantages of low flow system
Advantages: Easy and rapid set up, comfort, low oxygen concentration needs easily met, patient compliance Disadvantages: variable and limited FIO2, high flow drying and irritation, dislodging, sores from equipment, complications from nasal abnormalities, danger with patient abnormal breathing patterns
Continuous Med Nebulizers: Patients must be monitored when receiving continuous neb treatments for ______ ______.
Adverse reactions
Aerosol Therapy Aerosol Administration Equipment: __________ Masks Similar to the simple oxygen mask but with two large outlet ports to facilitate evacuation of any exhaled aerosol. These masks are specifically designed to be used with large bore tubing.
Aerosol
Bland Aerosol
Aerosolized water or saline (salt water) solutions that change the thickness and stickiness of mucus, sometimes making it easier to clear.
Particles suspended in a column of gas.
Aerosols
Aerosols are an _____________ of water molecules.
Aggregate
Why a clear mask?
Allows you to see more (breathing condensation, vomiting)
While Relative Humidity can be calculated for any gas temperature, provided the humidity table is available, clinically we are only interested in the RH of gas at the conditions that exist at the ___________ level.
Alveolar
ASTM
American Society Testing Material - specification design and performance
A Pop-Off alarm sounding off on a Cascade/Diffuser Heated Humidifier, what is this an indication of?
An OCCLUSION!! NOT a leak!
Aerosol
An aerosol is a colloid of fine solid particles or liquid droplets, in air or another gas. Examples of aerosols include haze, dust, particulate air pollutants and smoke
What is a Heat-Moisture Exchanger (HME)?
An often passive humidifier that is also known as an "artificial nose" that does not add heat or water to system. It also captures exhaled heat and moisture, which is then applied to subsequent inhalation
When is a bubble humidifier most commonly used?
Anytime flow greater than 4 L/min
Jet Reservior AKA
Aqua pak humidifier
Do not distinguish between oxyhemoglobin and ___________________.
Arterial
HME- HEat Moisture Exchanger AKA:
Artifical Nose
Aerosol Therapy Indications: Presence of an ____________ airway
Artificial
How is Body Humidity expressed?
As a %
How is Absolute Humidity expressed?
As mg/L
If patient at 40% it is 1:3, flowmeter is 8L/min: total flow: 32L/min. If you increase to 10 L / min did you change the oxygen percentage?
At 10 L/min flow to the patient is 40 L/min. you only increased the flow. The oxygen percentage stayed the same.
What are signs of inadequate humidification?
Atelectasis, Dry non productive cough, increased airway resistance, increase incidence of infection, increased WOB, Substernal pain, Thick secretions
Medical aerosols are generated with...
Atomizer, nebulizer, and inhaler
What is an advantage of using automatic reservoir feed systems?
Avoids need for constant checking and manual refilling.
bubble humidifiers are used on _____
BNC
What is added to the inspired air through the mucus lining of a patient's airways?
BTPS (Body Temperature Pressure Saturated)
As gas enters the lungs it achieves
BTPS: Body temp 37° C, Barometric Pressure; saturated with water vapor *at 100% relative humidity at body temp.
What is a croup?
Bacterial or viral
Jet Nebulizer: _________ - cause the larger particles to be knocked out of suspension.
Baffles
What are some instruments that allow positive-pressure ventilation?
Bag-mask LMA ETT
What are baffles?
Barriers
Due to the small jet orifice causing high resistance what is the upper flow rate range for many LVN
Because a small jet is used with this type of nebulizer and a high resistance is created, the upper flow rate available through a flowmeter is 12 -15 L/min
Why don't we use the bubble humidifiers in simple masks?
Because bubble humidifiers are designed for flow rates between 4 to 6 LPM. Simple masks are designed to handle flow rates 6 to 10 LPM. Nasal cannula is the mask to be used with the bubble humidifier.
HME consists of a honeycomb-like tubular structure, made of hygroscopic materials that allow for _____________ gas flow.
Bi-directional
Large Volume Nebulizers (LVN) are used for "_____" therapy.
Bland
AARC clinical practice guidelines divides it aerosol therapy in 3 categories
Bland Aerosol, aerosol to the upper airway, medicated aerosol
Ultrasonic Nebulizers (USN) These nebulizers are used primarily for _____ aerosol therapy for sputum inductions. They ARE NOT used to nebulize ______.
Bland; medications
What is the term for the Relative Humidity at body temperature?
Body Humidty
What does BTPS stand for?
Body temperature Pressure Saturated
What is BTPS?
Body tempressure pressure saturated Water vapor pressure is 47mmhg and contains 43.9 mgh20/L
Aerosol Therapy Possible Complications: Bronchospasm Prevention/Action: Review the patient's chart for indications of previous bronchospasm, reactive airways disease, or asthma. If these conditions exist, request an order for a __________________ before beginning therapy. Monitor all patients, even those without this history, for signs of bronchospasm once therapy is started.
Bronchodilator
MDIs or used to deliver what?
Bronchodilators, steroids, and anticholinergic drugs
Ultrasonic Nebulizers (USN) Hazards: __________ -- this type of nebulizer is the most likely to cause bronchospasm in individuals prone to bronchospasm. This is because these units produce a dense mist consisting of very small particles.
Bronchospasm
Random movement of small particles are called..
Brownian Movement and as particles decreases in size brownian movement increases
Surface Area also includes
Bubble Diffusion Aerosol "Wick" Technology
Type of humidifier that allows air to enter to a reservoir via a capillary tube where it picks up humidity as it moves toward the patient. The most common type of humidifier used for oxygen therapy.
Bubble Humidifier
What is the least efficient of the humidifiers?
Bubble Humidifiers
What is the most common type of disposable humidifiers used in Respiratory?
Bubble Humidifiers
Three types of humidifiers...
Bubble, aerosol, Passover
Pulse oximeters: Each of the probes are _________ for their specific use.
Calibrated
How do you fix the problems due to condensation on the circuit
Can be minimized with use of water traps and heated circuits, by positioning circuits so it drains condensate away from patient, and checking humidifier and nebulizer often.
Siphen tube is ________ tube
Capillary
Transcutaneous Monitor: The increased surface temperature causes increased ______ _______ ________ to the area.
Capillary blood flow
Jet Nebulizer: A _______ _______ connecting the liquid in the reservoir with the area of the local pressure drop, causing the liquid to be drawn up the capillary tube (Venturi Principle).
Capillary tube
Device that measures CO2 levels inline with the patient respiration.
Capnograph
What is another name for End-Tidal CO2 Monitor?
Capnograph
BTPS describes the conditions at the __________.
Carina
The tubing connecting the humidifier to the patient an have a heated wire internally to maintain ___________________.
Carrying capacity of the gas.
Another name for a Diffuser Humidifier is?
Cascade Humidifier
Which type of Humidifer is capable of producing a Body Humidity with gases at a HIGH Flow?
Cascade Humidifier
Berman OAW
Central I beam Side air channels
Guedel OAW
Central lumen Color
Ultrasonic Nebulizers (USN) are (expensive/cheap)
Cheap
The capnograph monitors have a _______ _______ paper that turns different colors in the presence of different levels of CO2:
Chemically active
What actions must you take when using Room Humidifiers?
Clean them regularly and change out the water in the reservoir frequently
Efficiency of a Bubble Humidifier depends on what?
Contact to the water level in the reservoir
simple condenser
Contain a condenser element with high thermal conductivity (Metallic gauze, Corrugated metal, Parallel metal tubes)
What is unique about a nonrebreathing mask?
Contains three unidirectional valves
Galvanic O2 Analyzers gives a ________ reading that cannot be turned off.
Continuous
Jet Nebulizer: Large volume Nebulizers (LVN) should not used to nebulize ________ _________. Why?
Continuous medication; Because they produce too many large particles that do not enter the airways.
Jet Nebulizer: Large Volume Nebulizers are primarily used for ______, ______ aerosol therapy, nebulizing ______ water.
Continuous; bland; sterile
Gas exiting from the regulator section then passes through a proportioning valve connected to the _______ ________ on the front of the blender.
Control dial
Aerosol Therapy Objectives: To increase _____ ______ temperature through the delivery of a heated aerosol (heated to 40 - 42o C)
Core body
as with heated humidifiers, rain out from the decreasing temps occurs so
Corrugated tubing must be free of excess water
What is a drawback of manual reservoir feed systems?
Cross contamination.
How does the crystal transducer in an ultrasonic nebulizer work?
Crystal transducer converts radio waves into high-frequency mechanical vibrations that produce the aerosol. Cuplent (liquid) takes vibration energy and transmits it to what is being delivered to the patient.
wick passover humidifiers
Cylinder of absorbent material (Placed upright in the water reservoir) -reservoir is heated
Bubble Humidifier: 1. Gas enters the humidifier through the ______ fitting on top. 2. Gas flows down through a hollow tube to a __________ element. 3. The __________ breaks up the gas flow into small bubbles. 4. As the gas bubbles float to the surface, the water ___________ into the bubbles.
DISS; diffusing element; diffuser; evaporates
Heated systems with incubator
DO NOT palce a temp probe inside a isolette or radiant warmer. The heat system will be shut off
The higher the flow rate used, the less time of contact between the gas and the water, thus ____________ humidity output.
Decreases
The lower the water level in the jar, the less time of contact between the gas and the water, thus _______ the humidity ouput.
Decreases
Ultrasonic Nebulizers (USN) delivers a _______ mist.
Dense
Pulse oximeters are perfusion _________. ( requires blood flow )
Dependant
The efficacy of the Metered Dose Inhalers (MDI) are patient ________.
Dependent
Jet Nebulizer: A Large Volume Nebulizer (LVN) produces a non uniform particle size that does not meet ______ needed for medication delivery.
Deposition
What factors should be used in selecting an oxygen delivery system?
Design: Low flow, Reservoir & High flow systems enclosures Performance How much oxygen can it deliver FIO2 fixed or variable FIO2 low: less than 35%, moderate (35 - 60%), high (>60%), full range (21 to 100%)
Aerosol Therapy Possible Complications: Swelling of secretions Prevention/Action: Monitor the patient recently placed on aerosol therapy for ______ in condition. Encourage ______ or ______ as necessary to mobilize secretions. A concern in the patient who is dehydrated. Providing high humidity may cause _____ secretions to swell as they absorb water, and these secretions may _____ airways.
Deterioration; coughing; suction; dry; block
Know how to use the magic box
Determines O2:air ratio when FiO2 is known: a. place FiO2 in center b. subtract FiO2 from 100 and put in bottom right corner c. subtract FiO2 from 21 and put is left corner. d. divide value of b from value of c e. this represents ratio of o2 and air. f. add together to get total ratio parts
A chemically active paper that use a color change to determine the presence of CO2. (Single Breath only) It is also used to immediately verify End-Tidal tube placement.
Disposable CO2 Detectors
The height of the water column does not effect humidity, only the ________ of the air/water Surface (known as the fetch)
Distance
Ultrasonic Nebulizers (USN) _______ water does not have the ions necessary to complete the electrical circuit, so the unit will not function if distilled water is used in the ______ chamber.
Distilled; couplant
What does a SVN for sputum induction do ?
Draws fluid out of tissue, causes mucous layer to increase, and makes it easier to cough up sample
Gases must be _______ when using Air Oxygen Blenders.
Dry
High Minute Volume (VE) cause ______ and ______ of secretion.
Dryness; thickness
Why do Pass-Over Humidifiers have low humidification?
Due to the decreased contact time and the limited surface area
Provides a valuable monitor of _____________ function.
Dynamic
The capnograph ___________ measures CO2.
Dynamically
why add a heater
ET tubing (bypassing upper airway)
Ultrasonic Nebulizers
Electric current that produces sound waves
The combination of the oxygen and the chemicals in the electrolyte produce an ______________ current.
Electrical
Ultrasonic Nebulizers (USN) Hazards: ______ ______ ______ -- water in the same area as electrical current.
Electrical shock hazards
How are Room Humidifiers powered?
Electrically
What is an ultrasonic nebulizer?
Electrically powered device that uses a piezoelectric crystal to generate a very fine and consistently sized aerosol.
Most of the analyzers in use today are__________: Either Galvanic or Polarographic.
Electrochemical
Galvanic Analyzers has a semi-permeable membrane, which allows oxygen, but not other gases, to come into contact with the ________________.
Electrolyte
The reactions Polarographic O2 Analyzers are ___________ in nature.
Electrolytic
immersion
Element is placed in the water reservoir
yoke or collar
Element sits between the water reservoir and the gas outlet
What is end-tidal?
End of exhalation
ETCO2
End tidal of Carbon Dioxide
The Capnograph is used to verify _____-_____ tube replacements. (Single breath)
End-Tidal
Polarographic O2 Analyzers requires ___________ to power it up by getting reaction. This is an (advantage/disadvantage) because the reaction stops when the power stops.
Energy; advantage
What is the Principle of Bernoulli and Venturi?
Entrains and accelerates gas
What is the Time of Contact principle in regards to humidifier function?
Evaporation increases as the contact time increases
Moisture and heat from the patient's ____________ _____ is absorbed into the exchanger.
Exhaled breath
The wick humidifier has an ___________ humidifier.
External
True or False: "Lower temperatures result in an increased humidity"
FALSE! Higher temperatures result in an increased humidity
A Large Volume Nebulizer (LVN) may have an adjustable window to adjust ______.
FIO2
Used to clinically verify and adjust the __________ delivered to the patient.
FIO2
What do the unidirectional valves in a nonrebreathing mask allow?
FIO2 increase Almost pure oxygen (no holes for exit) CO2 expire within the circuit
Jet Nebulizer: The design of jet nebulizers may also include a control to vary the ________ using the jet to entrain room air. The FIO2 is varied by changing the size of the _______ window.
FIO2; entrainment
T or F Decreasing height of water column above the gas outlet increase the humidity content of the bubbles
False
T or F The warmer the gas is the less water vapor it can hold
False
(True/False) Polarographic O2 Analyzers cannot be shut off.
False, Polarographic O2 Analyzers can be shut off. The reaction stops when powered down.
(True/False) All HMEs are bi-directional.
False, all HMEs are uni-directional. Because it has the hygroscopic element on the one side and a filter on the other side.
(true/false) It is harder to manage the temperature in the pass-over humidifier if there is a small amount of water in the reservoir.
False, because it is actually easier to manage the temperature if the reservoir has small amounts of water.
(True/False) Salt is not a common solute.
False, salt is a common solute.
(True/False) As temperature decreases, the carrying capacity stays the same.
False, the carrying capacity of gas decreases as the temperature decreases.
the higher the ______ gets the lower the total flow output will be (will need to increase the flow; get a mistogen or misty ox)
Fio2
How to size an OAW?
Flange at corner of mouth to tip at jaw angle
Determine what flow may be necessary to meet a patients inspiratory demand
Flow should equal or exceed three times the patients minute volume. If minute vol is 10L/min it is 10 x 3=30
Newer models of Ultrasonic Nebulizers (USN) are used to deliver medications as it limits ______ and ______.
Flow; deadspace
Aerosol Therapy Contraindications: _____ overload
Fluid
Compute the oxygen percentage of a mixture of air and oxygen
Formula: %O2 = (air flow x 21) + (O2 flow x 100)/ total air Ex: An air entrainment device mixes a fixed ratio of 3 volume of air to each volume of oxygen. What is the FiO2 %? (3 x 21) + (1 x 100) = 63 + 100= 163/3+1 = 163/4 = 40%
Oxygen analyzers that rely on a chemical reaction as oxygen passes through a membrane to measure small amounts of current.
Galvanic O2 Analyzers
Particles suspended in a ______.
Gas
Disadvantages of MDIs Some patients do not feel that they "___ _____" from an MDI.
Get anything
Generally what is the best oxygen system for a patient with COPD that has acute on chronic hypoxemia present?
Goal: ensure adequate arterial oxygenation without depression ventilation. SaO2 88-90 % PaO2 50-60 mmHg -Low flow nasal cannula or low concentration (24-28%) Less stable the patient, greater need for AEM
As particle size and mass increase,______ ______ forces act on the particle to a greater degree, tending to remove it from suspension.
Gravitational forces
Influences patient's position.
Gravity
A particle with (greater/smaller) mass, when placed in motion, will have a greater inertia than a particle with a (greater/smaller) mass.
Greater; smaller
Types of OAW
Guedel (color) Berman
What's up with that cross-contamination?
H2O in the circuit can be a source of bacterial colonization
What is the humidity deficit for a patient breathing gas at 30o C which contains 15 mg/L of water vapor?
HD = 44 mg/L - actual content HD = 44 mg/L - 15 mg/L HD = 29 mg/L The 30o C given in the above example is a distracter. If you are given the water vapor content, the temperature of the inspired gas is unimportant. This is because we are not interested in the humidity deficit as the gas enters the pulmonary system, but only when it reaches the alveoli.
What type of Humidifier are also called an "Artificial Nose"?
HME
A device that uses a hygroscopic element and the patient's heat and humidity from exhaled gas to humidify the next breath.
HME (Heat Moisture Exchange)
Name the type of Humidifier that traps the patient's body heat and expired water vapor to raise the humidity of inspired gas.
HME (Heat-Moisture Exchanger)
A simple device whose function can, in many instances, temporarily replace the need for a humidifier.
HME (Heat-Moisture Exchangers)
What improves water output of bubble and Passover humidifiers?
Heat
What is HME stand for?
Heat Moisture Exchange
HME
Heat and moisture exchanger: Active type: actively adding heat and or water to device Passive type: recycling exhaled heat and humidity from the patient
What are drawbacks of utilizing enclosures?
Heat retention & CO2 build-up in tents.
Water ___________ in to the gas, increasing the humidity of the gas.
Heated
Wick humidifier is hooked up to the __________ system.
Heated
What is a drawback of using heating systems?
Heating inhaled gas can expose patient to a risk of airway burns.
wraparound
Heating unit surrounds the humidifier
The ___________ element surrounds the wick and the reservoir, ____________ the rate of evaporation.
Heating; increases
If a patient is hypoventilating the FIO2 received is (low/high)?
High
What type of flow device would you use when wanting to give a precise FIO2?
High flow device
What can be done to remedy CO2 build-up in airway tents?
High flows of fresh gas circulating continually through tent help "wash out" CO2 build up
Why would you choose a high flow mask over a low flow mask?
High has the ability to deliver predictable, consistent, and measurable high and low FIO2s despite ventilatory patterns
How can you tell if a Pass-over humidifier is a high-flow or a low flow?
High-flow Pass-over Humidifier has a bigger opening in the inlet. Low-flow Passover Humidifier has a smaller opening in the inlet.
What are the 2 types of Continuous Med Nebulizers?
Hope and Hart
What are some types of heating elements that require energy source?
Hot plate humidifier base, wraparound type, yolk/collar element, immersion-type heater & heated wire.
hot plate
Hot plate-like element is located at the base of the humidifier
What is used in order to add water and/or heat to a dry gas during Oxygen administration?
Humidification
active humidifier
Humidification device in which energy (heat) is used to add water to the inspired gas.
Temperature effects what ?
Humidity
Term for water that is in a gaseous or vapor form is?
Humidity
Water that is present in a gas mixture (parcel of air) as a vapor.
Humidity
BTPS added to the inspired air through the mucus lining of a patient's airway creates _________ ___________.
Humidity Deficit
The ________ ________ is the amount of water vapor that must be added by the body to bring the inspired gas up to BTPS conditions.
Humidity Deficit
The term for a physiological difference between inspired gas's water content and the water content of a gas at body temperature, is?
Humidity Deficit
What is this formula? 44 mg/L - Specific Humidity
Humidity Deficit
Any air breath in at less than BTPS creates a __________ _________.
Humidity deficit
What is the term for inspired air that is not fully saturated at body temperature?
Humidity deficit
The warmer the air the more what ?
Humidity it is capable to carry
________ has a tendency to absorb water.
Hygroscopic
____________ solutions will gain water from body fluids due to the greater concentration of solutes.
Hypertonic
Aerosol Therapy Indications: _____ (heated aerosol)
Hyportermia
____________ solutions will lose water since the solute concentration is less than that of body fluids.
Hypotonic
HME's standards are set by
ISO
What will happen if the temperature of the carrier gas increases with the humidity held constant?
If the temperature of the carrier gas increases, with humidity held constant, the aerosol particles will have a tendency to evaporate into the carrier gas, thus making the particles smaller.
Pulse oximeters are _________ with cold pts, very low blood pressure, pts, and dark nail polish
Inaccurate
Jet Nebulizer
Incorporates Bernoullis prinicple, baffles, atomizers
What do can you do to increase the humidity of a gas?
Increase the temperature.
Increasing the amount of time the gas is in contact with the water will (increase/decrease) humidity. Decreasing the amount of time the gas is in contact with the water will (increase/decrease) humidity.
Increase; Decrease
Increasing the surface area for contact will (increase/decrease) the humidity. Decreasing the surface area for contact will (increase/decrease) the humidity.
Increase; Decrease
Heat & Moisture Exchangers contraindications
Increased volume of secretions Thick, dehydrated secretions Hypothermia Large tidal volumes (> 1000 mls) Small tidal volumes with large-volume HMEs During aerosol therapy With heated humidification Airway leaks around a an artificial airway
Hypotonic or hypertonic solutions are used t
Induce a cough and/ or sputum induction
Influenced by flow rate. (mass x velocity)
Inertia
Mass x Velocity = ___________
Inertia
_________ are also related to particle size and mass.
Inertia
What influences the depositions of aerosols
Inertial Impaction, gravity, kinetic activitiy, physical nature of particles, temp/humidty, ventilatory pattern, characteristics of pt airway
Hazards of aerosol therapy
Infection, bronchospasm, overhydration
Jet Nebullizer: A slow, deep __________, followed by a brief _______ before exhalation, will increase aerosol deposition in the lungs.
Inhalation; Hold breath
Metered Dose Inhalers (MDI) takes coordination. Slow _________ with breath _________.
Inhalation; hold
Simple mask:
Input flow range 6-12 L/min FIO2 range .35 to .55 -Flows greater than 12 L/min to maintain oxygenation, you should switch to a different system. Flows at 5L/min or less causes CO2 rebreathing. Used in ambulance
Simple Condenser mechanism of action
Inspired air cools the condenser element Expired water vapor condenses directly on it's surface and re-warms it During inspiration, cool, dry air is warmed and humidified as it passes over the condenser element
Jet Nebullizer: Good patient _______ and _______ can influence the effectiveness of aerosol therapy to a large degree.
Instruction; monitoring
Design and performance standards are set by the
International Organization for Standardization (ISO) (70 % efficacy rate)
What is ISB?
Isotermic saturation boundary 5cm below carina, temperature and humidity decrease during inspiration and increase during exhalation
What is the ISB?
Isothermic saturation boundary where it's at 100% BH
What effect does Temperature have on Humidifiers?
It increases the kinetic activity
What is water vapor content?
It is measured in mg of water in liters of air (mg/L)
What is the carrying capacity of a gas at 37 degrees Celsius?
It is saturated (full) at 44 mg/L
Is HME very efficient?
It is somewhat efficient
What is significant about 37 degrees Celsius?
It is the temperature pass the carina. (This is the temperature pass the carina when inhaling air regardless of the temperature.)
To ensure a stable FiO2 under varying patient demands, what must a oxygen delivery system do?
It must supply a given O2 concentration at a flow equaling or exceeding the patients peak inspiratory flow.
How does heated humidifiers work?
It operates ACTIVELY to increase the heat and water vapor content of inspired gas.
How do HMEs work?
It operates PASSIVELY by storing heat and moisture from the patient's exhaled gas and releasing it to the inhaled gas
What are some physical maneuvers to adjust the obstructed airway?
Jaw thrust maneuver Turn head/Chin lift Mandibular displacement
Jet Nebulizer: A ______ which creates an acceleration in the flow of gas, causing a local pressure drop (Bernoulli Principle)
Jet
Jet Nebulizer: As the liquid is drawn up the capillary tube, it intersects with the ______ stream, which then shatters the liquid into _______ particles, which are then carried out to the patient.
Jet; aerosol
Metered Dose Inhalers (MDI): The spacer creates a slower and more _______ delivery
Laminar
Aerosol Therapy Aerosol Administration Equipment: __________ Bore Tubing Corrugated tubing, frequently provided in 200-foot rolls.
Large
Jet Nebulizer: A typical (small/large) volume nebulizer should not be used to deliver continuous medication because they produce too many very large ______ that do not enter the airways. Also, the ______ ______ Nebulizer should not be used to deliver bland aerosol therapy because these nebulizers are expensive and bland aerosol therapy does not require such ______ particle delivery.
Large; particles; Continuous Mediation; uniform
Mechanics of Large-Volume jet nebulizer
Liquid particles are generated by passing gas at high velocity through small jet orifice. Low pressure at jet draws fluid from reservoir up siphon tube. H2O is then shattered into liquid particles. Smaller particles leave the nebulizer through the outlet port into the gas stream.
The particles may be in a state of _______ or ______
Liquid; solid
If the patient is hyperventilating the FIO2 received is (low/high)?
Low
Types of supportive oxygen therapy
Low flow and high flow devices
This capnograph monitor works because any measured CO2 has to come from the ________, the only source of CO2 in the body.
Lungs
Nasal cannulas are typically used with what type of anesthesia technique?
MAC (Monitored Anesthesia Care)
What measures the diameter that divides the range of particle size in half
MMAD Mass medican aerodynamic diameter
Goal for Humidification
Maintain normal physiological conditions in lower airway
In a PRE-FILLED Bubble Humidifier, if the Oxygen fails to flow from the Humidifier, what should you check?
Make sure the reservoir has been pierced and that the gas can flow through it
Face mask fit
Mask should fit over the bridge of the nose, cheeks, and chin to produce an airtight seal
Aerosol Therapy Possible Complications: Caregiver exposure to droplet nuclei. Prevention/Action: Wear a _____ if the patient has a communicable pulmonary disease or is coughing actively. Organisms are transmitted on _____ particles, not via water in the form of a vapor.
Mask; aerosol
mass median aerodynamic diameter (MMAD)
Measurement that expresses the geometric size of the particles of an aerosol; for medical use, aerosol generators produce respirable particles with an MMAD of between 1 to 5 μm.
Aerosol Therapy Indications: Need to deliver _____________
Medications
Jet Nebulizer: Small Volume Nebs (SVN) are used to deliver _______.
Medications
Metered Dose Inhalers (MDI) delivers a ________ dose of medications with each acuation.
Metered (exact)
Jet Nebulizer: (SVN) _______-________ is a single dose medication delivery (Mini-Neb)
Micro-Nebulizer
Open loop system
Microprocessor controlled system that provides clinical data or advice but defers to the user to take appropriate action
Metered Dose Inhalers (MDI) is more effective than ______-_______with patients that are not profound SOB and can coordinate procedure.
Mini-nebulizers
Oxygen Analyzers are affected by __________ and ________ ________.
Moisture; High Pressure
How does breaking air in to small bubbles increase the humidity output in a bubble humidifier?
More (small) bubbles increases the surface area of the gas. More bubbles creates more surface in contact with the reservoir.
The warmer the gas, the (more/less) water may be carried as a vapor. Colder gas carries (more/less) water vapor than warm gas.
More; Less
Heated Humidifier Systems are
Most often used when the upper airway is bypassed for an extended period of time
Air Oxygen Blenders are mostly used with _____ applications.
NICU
Transcutaneous Monitor is very widely used in ____________ units, not so much in adult units.
NICU
Transcutaneous Monitors are generally used in __________ applications only.
NICU
which meds can be directly instilled in an ETT?
Narcan (to reverse narcotics) Atropine (given for bradycardia) Valium/versed (sedation) Epinephrine (asystole) Lidocaine (arrhythmias/PVC)
If you increase the L/flow to the patient in a high flow system do you increase the amount of flow they are getting?
No
Is the wick humidifier more efficient than the pass-over humidifier even if it is not heated?
No (not a heated pass-over), because you still have the problem with the cups.
Bland means:
No meds
Can an Oxygen Analyzer deliver a precise FIO2?
No, Air Oxygen Blender delivers a precise FIO2. Oxygen Analyzers measures precise FIO2.
If I make the reservoir deeper, do I get increasing humidity output? Why?
No, increasing the surface area of the gas in the reservoir increases the humidity output. Making the reservoir deeper does not increase humidity.
Bubble Humidifiers are also called?
Non-Heated Bubble Humidifiers
Nasal Cannula
Normal FIO2 ranges .24- .44 FIO2 -Disposable plastic device - .5-6L/min -Use of humidifier above 4 L/min or if patient has drying or nose irritation -Flows above 6-8 L/min cause patient discomfort. Nasal dryness, bleeding High flow N/C with humidity have solved some of these problems -Newborn infants not to exceed 2 L/min
Continuous Med Nebulizers are not to be used with _______ ________ (0.9%).
Normal Saline
What happens when there is a humidity deficit ?
Normal humidification is inadequate
What is humidity deficit?
Normal humidity range (44 mg/H20) minus actual humidity
Ultrasonic Nebulizers (USN) Hazards: _____ ______ -- always a concern where liquids are involved.
Nosocomial Infections
Pulse oximeters cannot differentiate between _____
O2Hb and COHb
What are some instruments that can be used to adjust the obstructed airway?
OAW NAW
Anesthesia face mask characteristics?
Opaque or transparent body 22 mm connection Air-filled seal Retaining ring
What are the potential passageways to relive airway obstruction?
Oral route Nasal route
Also has a semi-permeable membrane that allows ___________ to pass through to the electrolyte, but prevents other gases from moving across the membrane.
Oxygen
Galvanic Analyzers rely on the chemical reaction that takes place when ___________ combines with certain electrons.
Oxygen
Pulse oximeters provide continuous monitoring of ___________ saturation.
Oxygen
What do 100% of patients receive?
Oxygen
What do you do for a patient attempting to spontaneously breath but airway obstructed?
Oxygen Airway support (physical or instrument) Assist breathing (bag/controlled respirations) Dial back anesthetics slightly
What would you do for a patient with a neuromuscular blockade (paralyzed)?
Oxygen Positive-pressure ventilation
Pulse oximeters use light transmitted or reflected by ___________ vs. ____________ hemoglobin at specific wavelengths (photoplesmography).
Oxygenated; Deoxygenated
Pulse oximeters: CO reads as _________.
Oxyhemoglobin
List diagnostic application for computer usage in hospital
PFT, x ray, echo
The Capnograph uses a trend exhaled CO2 concentrations as a way to estimate _________.
PaCO2
Transcutaneous monitors monitor ________ and ________ levels.
PaO2; PaCO2 (TCPO2; TCPCO2)
Nitrogen/O2/CO2 exert their own what ?
Partial pressure totaling 760 mg
Three characteristics of therapeutic aerosols
Particle size, aerosol output, sedimentation
What influences inertial Impactions?
Particles 1-5 microns Larger particles are effected by gravity Gas density
A bland aerosol consists of...
Particles suspended in a gas providing humidity and additional liquid applied locally to the airway.
Hygroscopic particles
Particles tend to absorb water grow in size
Which type of Humidifier functions by having gas passing over the surface area of the water, picking up the moisture and delivering it to the patient?
Pass-Over Humidifier
When to use a NAW?
Patient is semiconscious Oral airway placement difficult
Who are heating systems primarily used for?
Patients with bypassed upper airways and those receiving mechanical ventilation
What is relative humidity ?
Percentage of full saturation
Transcutaneous Monitor: ____________ of O2 and CO2 into the electrode causes an electrical charge that is transmitted to the recorder and reported as PaO2 and PaCO2.
Perfusion
Transcutaneous is ________ dependent.
Perfusion
Pulse Oximeters works by principle of _________.
Photoplethsmography
_______________ uses 2 light sources to read oxygenated blood and deoxygentated hemoglobin.
Photoplethsmography
List clinical application for computer usage in hospital
Physicians orders, progress notes, discharge summary
Ultrasonic Nebulizers (USN) The ______ ______ changes shape as an electrical current is applied to it, thus changing electrical energy into mechanical energy. This produces the _____.
Piezoelectric crystal; aerosol
Temporary monitors are used to evaluate the correct _________________ of an artificial airway following intubation.
Placement
How do Large-Volume Jet Neutralizers work?
Pneumatically powered and connected directly to a flow meter and a compressed gas source. Variable air-entrainment port allows air mixing to increase flow rates and to alter the FiO2
O2 Analyzer that is similar in design and function to galvanic analyzers.
Polarographic Analyzers
What kind is commonly used in hospitals? Why?
Polarographic Analyzers, because it does not continuously use receptors.
A device similar to a Galvanic O2 Analyzer but uses its power source to increase speed of reaction.
Polarographic O2 Analyzers
What type of ventilation pressure is used when assisting someones breathing?
Positive-pressure ventilation
What can we use to control an airway?
Positive-pressure ventilation -bag-mask ventilation -LMA -ETT Spontaneous ventilation (negative) -bag-mask ventilation -LMA -ETT
What is precipitation?
Precipitation is going from a less organized matter to a more organized matter. Example: Gas to Liquid.
Jet Nebulizer: _______ drop is used to draw up a fluid from a reservoir through a siphen tube.
Pressure
What is the first priority in Oxygen therapy and COPD
Preventing hypoxia
What is the primary goal of a heated humidification system?
Primary goal is to match the output of the humidifying device to the normal inspiratory conditions occurring at the level of the trachea
What is the principle of operation of a jet nebulizer?
Principle of Bernoulli and Venturi
What is the principle of operation of all humidifiers?
Principle of Evaporation
Pulse oximeters have many different _________.
Probes
___________ ____________ are used to mix gases in Air Oxygen Blenders.
Proportioning valves
What does the human airway do?
Protect, conduction, air conditioning
What is suggested active humidification to patients who are invasively ventilated?
Provide a humidity level between 33 mg H2O/L and 44 mg H2O/L and gas temperature between 34°C and 41°C with a RH of 100% to prevent the drying out of secretions in the artificial airway.
Airway management is important because?
Provide anesthesia for surgery Support resuscitation Provide long-term respiratory care
LVNs are for...
Providing longterm aerosol
A perfusion monitors that measures pulsatile oxygen.
Pulse Oximeter
Device that measures the oxygen saturation in pulsatile blood. (SpO2) or the percent of oxygen attached to the hemoglobin in the capillary beds.
Pulse Oximeter
Capnograph: __________ = Problem = __________________ __________ = Think = __________________ __________ = Yes = __________________
Purple; No CO2 detected Tan; The airway may be in esophagus Yellow; the airway is in the trachea
Advantages of MDI over SVN Less _____ time is required to deliver medication via MDI than by SVN
RCP
What is the relative humidity at the alveolar level for a gas at BTPS if the actual content is 25 mg/L?
RH = (actual content/total capacity) x 100 RH = (25/44) x 100 RH = 56.8% In this example, the gas is carrying 57% of the maximum amount of water vapor that it could carry under BTPS conditions.
relative humidity is expressed as
RH = content/capacity x 100
relative humidity equation
RH= content/capacity x 100
End-Tidal used to titrate amount of support given to patients requiring ___
RPV assistance
Ventilatory pattern and characteristics of patients airway is influenced by....
RR, Inspiratory gas flow and inspiratory pause
What is Poiseuille's law?
Raw=8nl/ pi r ^4
Proper Humidification of inspired gas will_______ the humidity deficity
Reduce
Indications of Bland Aerosols
Reduce upper airway edema, induce sputum, humidify dry medical gasses
A ___________ __________ sounds if there is a drop in the pressure of 1 of the gases.
Reed valve
If the Bubble Humidifier's PERMANENT reservoir is low, what should you do?
Refill with sterile water
What are the 2 airway defenses?
Reflex Response Mucociliary Apparatus
The term for the ration between the amount of water in a given volume of gas and the maximum amount it is capable of holding at that temperature is?
Relative Humidity
What humidity is the comparison of the actual humidity to air's carrying capacity?
Relative Humidity
The actual amount of water vapor present in a gas (specific humidity) divided by the water vapor capacity at a given temperature. (or, what you have divided by the most you could have).
Relative Humidity (RH)
What formula is this? Actual content/H2O vapor capacity x 100%
Relative Humidity (RH)
Question 1 Given the content and capacity of water vapor in a gas be able to determine its relative humidity
Relative humidity = content / capacity x 100%
Body Humidity is...
Relative humidity at body temperature, expressed as a percentage (AH/44mg/L)x 100
Humidifiers aid in what ?
Removal of thick secretions
If the Bubble Humidifier is DISPOSABLE, what would you do if the water level in the reservoir is low?
Replace the set-up
Aerosol Therapy Possible Complications: Sepsis Prevention/Action: Use proper technique when ______ or ______ equipment. Change equipment per Department Policy.
Replacing; refilling
In pass-over humidifiers, the gas flow passes over a ______________ of water.
Reservoir
Jet Nebulizer: A _______ containing a liquid to be nebulized.
Reservoir
These operate by bubbling gas through a ____________ of water.
Reservoir
List clinical signs of hypoxia
Respiratory: Mild to Moderate: Tachypnea, dyspnea, paleness Severe: Tachypnea, dyspnea, cyanosis
Proper humification prevents.....
Retention of secretions, airway plugging, airway obstruction and infection with pathogenic bacteria
What are two types of double lumen ETTs?
Robertshaw -left or right Carlens-has hook
Which type of Humidifiers have a large reservoir, which may lead to nosocomial infections due to the increase of bacterial growth?
Room Humidifers
What are equipment for humidity?
Room Humidifier, Bubble Humidifier, Cascade humidifier, Wick Humidifier, and HME
Which type of Humidifiers work off of the principle of Centrifugal Force?
Room Humidifiers
Jet Intermittent AKA
SVN, Med Neb, and breathing tx
jet intermittent is also known as
SVN, med neb, or breathing treatment
What structure is found on a Bubble Humidifier in order to relieve the pressure in case the path becomes obstructed?
Safety Relief Valve
Water follows _______.
Salt
How does condensation occur?
Saturated gas cools as it leaves the humidifier to the delivery tubing en route to the patient. As the gas cools, its water vapor capacity decreases resulting in condensation/rain out.
HME is not indicated with very thick ___________, High __________, and low _______________.
Secretion; Minute Volume (VE), Body temperature
A Large Volume Nebulizer (LVN) are used to liquefy __________.
Secretions
Ultrasonic Nebulizers (USN) are used in the liquefaction of ________.
Secretions
Without humidification, what happens to the secretions in the patient?
Secretions become thicker, dryer, and more difficult to mobilize and get rid of
On what type of patient do you use an OAW?
Sedated
membrane
Separate water from the gas stream by a means of a hydrophobic membrane
HME device may be used for _____-term or _____-term therapy.
Short; long
types of Heat & Moisture Exchangers
Simple Condenser Hygroscopic Condenser Hydrophobic Condenser
What are characteristics of a manual reservoir feed system?
Simple large reservoir that is manually opened and refilled with sterile or distilled water.
How do we encourage deposition
Slow RR, Slower inspiratory flow, longer inspiratroy holds
Aerosol Therapy Possible Complications: Fluid overload Prevention/Action: If the patient is an adult, review the patient's chart for indications of decreased cardiac function. This is a concern only in two populations...._________ children and those with severe _________ disease.
Small; pulmonary
The Metered Dose Inhalers (MDI) are more effective when using a ______ (______ ______)
Spacer; Holding chamber
MDI (Metered Dose Inhalers) Frequently combined with a ______ or ______ ______.
Spacer; holding chamber
Advantages of MDI over SVN Medication can be delivered by SVN at home, but this requires ______ ______. The MDI can be easily carried in a pocket, backpack, or purse, and used at any time or place.
Special equipment
Used to mix air and oxygen to _______________ concentrations.
Specific
What type of humidity that gives the actual amount of water vapor?
Specific Humidity or Water Vapor
Aerosol Therapy Indications: Need to obtain ___________ specimens or mobilize secretions.
Sputum
What is a cost-effective, and safe method for diagnosing TB, Pneumocystis Carini, pneumonia and lung cancer.
Sputum induction
Aerosol Therapy Objectives: To obtain a ______ _______ from within the lungs for either culture or for examination for possible abnormal cells.
Sputum sample
What types of liquid can be used in bland aerosols?
Sterile water & Sterile saline (hypotonic, isotonic and hypertonic)
Most common bland aerosol are.
Sterile water, hypertonic saline
Neither of these analyzers measures FIO2 directly. Both monitor a chemical reaction, and the ________ or _________of that reaction is used to determine the FIO2.
Strength; weakness
Just calibrating the analyzer to room air is inadequate. Remember that these analyzers are actually monitoring the _______ or ________ of the current produced by a chemical reaction. It requires very little ________ to produce a current that reads as 21% oxygen. However, as the electrolyte is exhausted, you may not be able to produce enough _________ to produce a reading of 100%.
Strength; weakness; electrolyte; current
Indications for cool bland aerosols
Stridor, epiglottitis, subglottic edema, postextubation edema
Increasing the water ________ _________ (2 words) will increase the humidity
Surface Area
What is the Surface area principle in regards to humidifier function?
Surface area affects the rate of evaporation
What is stridor?
Swelling associated with mild trauma.
Aerosol Therapy Objectives: This is still listed as an objective for aerosol therapy, although most studies indicated that ______ ______ is as effective, if not more so, at reaching this objective.
Systemic hydration
What is the most effective method to improve thick secretions ?
Systemic hydration with intravenous fluids
Aerosol Therapy Aerosol Administration Equipment: __-Tube (also called a Briggs Adapter) Attaches directly to the artificial airway. Usually, a short (approx. 6 inches, or one section of aerosol tubing) is placed at the outlet of the adapter to provide for a reservoir for oxygen and aerosol.
T
Transcutaneous Monitors read _______ and _______.
TCPO2; TCPCO2
Ultrasonic Nebulizers (USN) uses ____ water and ________ disk to generate mist.
Tap; piezoelectric
maximum absolute humidity is expressed as
Temp. x mg of H2O/L of gas
Bubble humidifiers cannot add heat. Therefore, it is limited by _____________.
Temperature
In humidity, the gas ____________ determines the maximum amount of humidity that can be carried by a gas.
Temperature
Increasing the _____________ of the water may increase efficiency.
Temperature
Question #15 What is the most important factor for ^ humidifier performance?
Temperature
Physical Factors Affecting Humidifiers
Temperature Surface Area Contact Time
What is temperature, PH2O, and Specific Humidity of BTPS?
Temperature = 37 C PH2O = 47 mm Hg Specific Humidity = 44 mg/L
BTPS consists of:
Temperature, PH2O, and Specific Humidity
What three factors are added to Humidifiers to increase their effectiveness?
Temperature, Surface Area, and Contact Time
What are factors that affect humidity
Temperature, Surface area, Gas-liquid contact time
Factors that affect humidity performance...
Temperature, surface area, time of contact
Absolute Humidity is....
The actual content or weight of water present in a given volume RHxCap
Humidity Deficit
The actual moisture deficit between the inspired air and the needs of the body
What is absolute humidity?
The amount of H2O in a given volume of gas (measured in mg/L)
Body Humidity
The amount of water vapor in a gas sample as compared to the capacity of water vapor at body temperature (37° C) Expressed as a percentage
Humidity deficit
The amount of water vapor the body must add to the inspired gas to achieve saturation. capacity - content = humidity deficit
What can happen if Isothermic saturation boundary shifts?
The body's normal heat and moisture exchange mechanisms can be compromised.
When the air reaches what structure, has the air been warmed to body temperature of 37 degrees Celcius and is 100% saturated?
The carina
Polarographic and Galvanic Analyzers have the same disadvantages except for:
The cell is continuous for polarographic analyzers and it lasts much longer.
As a bubble humidifier is used, what happens to the efficiency of it?
The efficiency decreases.
What is the Thermal Mass principle in regards to humidifier function?
The greater the amount of water in the humidifier, the greater the thermal mass and capacity to hold and transfer heat to the therapeutic gas.
If you see a DECREASE in the condensation in a Cascade/Diffuser Heated Humidifier, what is this a sign of?
The heating element is not functioning adequately
When the water level is low in a Cascade/Diffuser Heated Humidifer, what happens?
The heating element shuts off
What is the temperature principle in regards to humidifier function?
The higher the temperature of gas the more H2O it can hold.
Give an example when a chronic obstructive pulmonary disease patient may need high FIO2
The less stable the patients condition, the greater the need for high flow AEM
contact time
The longer a gas remains in contact with water, the greater the amount of evaporation
Maximum Absolute Humidity
The maximum amount of water vapor a gas can hold at a given temperature
You are asked to show an adult patient how to properly use a TriFlo incentive spiromenter. Although the patient appears to be following your instructions, she is unable to achieve the prescribed goal that you have established for her. Briefly describe several factors that could cause this problem.
The most common problem encountered involves a leak in the system caused by a crack in the device, defective tubing, or failure of the patient to maintain a tight seal around the mouth piece.
isothermic saturation boundary (ISB)
The point at which inspired gas is fully saturated at body temperature (44 mg/L at 37° C), approximately 5 cm below the carina at the level of the third-generation airways.
A clogged inlet on a Bubble Humidifier would prevent what?
The pop-off alarm from sounding
What is water vapor?
The presence of individual free molecules of a substance that exits below its critical temperature
What is relative humidity?
The ratio between the amount of H2O in given volume of gas and the maximum amount it is capable of holding at that temperature.
Relative Humidty is....
The ratio of actual content and water present in a gas sample relative to samples capacity to hold water at that temp. (AH/Cap)x100
relative humidity
The ratio of the actual amount of water vapor present in a gas compared to the maximum amount of water vapor that the gas can hold at a given temperature
What is body humidity?
The relative humidity at body temperature (37 degrees Celsius) expressed as a percentage. Capacity of H2O at 37 Celsius is 44 mg of H2O
Absolute Humidity
The weight of water vapor in a gas volume
Define hyperbaric oxygen therapy, listing indications and complications and compare and contrast two ways it is delivered.
Therapeutic use of O2 greater than 1 atm. one ata = 760 mmHg. conducted between 2 and 3 ATA -Indications: treat divers with decompression sickness, air embolism, carbon monoxide poisoning, gangrene, nonhealing wounds, refreactory osteromyelitis, radiation necrosis complications: Barotrauma which includes eye or sinus trauma, tympanic membrane rupture, pneumothorax, air embolism. oxygen toxicity which includes central nervous system roxic reaciton and pulmonary toxic reaction.fire, visual changes, claustrophobia Delivered:multiple chamber which holds a dozen and goes to 6ATA. Used for decompression or embolism. monoplace chamber
If there is no alarm on a Bubble Humidifier, what is the cause?
There is a leak
What are contraindications of Humidity Therapy?
There really are NO contraindications to humidity therapy other than patient refusal.
If a Reservoir runs dry on a Cascade/Diffuser Heated Humidifier, what safety system functions to automatically cut off the Humidifier?
Thermostat
What happens the particles less than 1micron
They are often exhaled out
What happens to hypotonic aerosols when they evaporate...
They decrease in size travel down the respiratory tract
What does transcutaneous mean?
Through the skin
Question #14 time contact effect humidifiers performance?
Time of contact between gas and water -longer a gas is in contact with water, greater opportunity for evaporation to occur -time contact directly related depth of water, inversely related flow rate gas through water (T.L.T)
Sizing of NAW?
Tip of the nose to the tragus of the ear
What is the purpose of Humidification?
To "make-up" for the water that is loss when a dry gas is delivered or when the upper airway is by-passed
What does the hygroscopic mean?
To accept and release water rapidly
What are enclosures (Mist tents and hoods) used for?
To deliver aerosol therapy to infants and children
What is the objective of humidity?
To make up for water loss when administering a dry gas
Define a true high flow oxygen delivery system
To qualify as a high flow device, a system should provide at least 60L/min total flow. This flow criterion is based on the fact that the average adult peak inspiratory flow during tidal ventilation is 3x the minute volume. Because 20L/min is close to the upper limit of sustainable minute volume for persons who are ill, a flow of 3 x 20, or 60L/min should suffice.
What is the number one cause of airway obstruction?
Tongue *New research suggest soft palate
Insertion of OAW?
Tongue depressor to pull tongue forward Insert upside-down and rotate 180
Describes solution concentration.
Tonicity
_______ refers to the concentration of solutes in a solution relative to their concentrations in body fluids.
Tonicity
NAW complications?
Too long: esophageal intubation Laryngospams Vomiting (less likely than OAW) Nasal mucosa injury and secondary blood aspiration Epixtaxis Tissue Necrosis
Complications with OAW?
Too long: obstruct larynx by forcing epiglottis Too short: pushes tongue into airway Vomiting and laryngospasm in awake patient
Aerosol Therapy Aerosol Administration Equipment: _____ Masks Designed to fit over a tracheostomy tube, secured by an elastic strap around the neck. A 22-mm large bore inlet fitting accommodates the aerosol tubing, and a single large outlet port allows for evacuation of exhaled aerosol.
Trach
Capngraph used to determine the _________ ___________ concentration in exhaled gases.
Trend CO2
(True/False) All analyzers must be calibrated.
True
(True/False) As temperature increases, so does the carrying capacity of gas.
True
(True/False) HME is used to treat patients because it is cost effective (cheap).
True
(True/False) Pulse Oximeter is only accurate as much as you can verify the settings.
True
(True/False) Pulse Oximiter is considered to be 4th in the vital signs in the hospital.
True
Polarographic Analyzer: The fuel cells last longer because the analyzer can be _________ _________, stopping the chemical reaction, between uses.
Turned off
passive humidifier
Type of humidifying device that uses exhaled heat and moisture to humidify the inspired gas; a heat and moisture exchanger (HME) is a passive humidifier.
What is the water output range for an unheated and heated LVN?
Unheated 26-35 mg/L water output Heated: 33 - 55 mg/L water output
URL
Uniform resource locator
Cool sterile water or saline are used to treat what part of the airway?
Upper
Aerosol Therapy Indications: ______ ______ ______ (cool aerosol)
Upper airway edema
Aerosol Therapy Objectives: To decrease work of breathing by decreasing _____ _____ ______.
Upper airway edema
Medicated Aeresol Delivery indications
Upper airway edema and flammation, topical anesthesia, relief of seasonal allergy
What can you do to avoid constant refilling of humidifier reservoirs?
Use a large water reservoir and utilize a gravity feed system.
Wick humidifiers
Use a water absorbent material to increase surface area. The wick draws water like a sponge to a fine honeycombed structure by means of capillary action .... like bounty -The surface of the wick increase the area of contact between the water and the gas.
Hydrophobic Condenser
Use a water-repellant element with a large surface area and low thermal conductivity
What is the purpose of a BUBBLE humidifier?
Usually used unheated with oxygen delivery systems to raise the water vapor content of gas to ambient levels by breaking underwater gas stream into small bubbles
H₂0 + Temp
Vapor
HME is used as initial method of humidification with mechanically _____________ patients.
Ventilated
What are some high flow devices?
Venturi mask Aerosol mask T-piece
Does a warm gas or a cold gas have a greater capacity for water vapor?
Warm gas
Vaporization is the result of....
Water changing to a vapor and can result from evaporation
What is humidity
Water that exists as individual molecules in the vaporous or gaseous state
Humidity
Water vapor content in air
What are the results of changing conditions ?
Weather/condensation/evaporation
The __________ humidifiers are the most heated and the most efficient.
Wick
Which type of Humidifier is SERVO-CONTROLLED?
Wick Humidifier
Which type of Humidifier is capable of producing 70% BH?
Wick Humidifier
Which type of Humidifier is ideal for patients on a mechanical ventilation?
Wick Humidifier
Which type of Humidifier utilizes a Cylinder of absorbent paper paper to draw water from the reservoir by capillary action?
Wick Humidifier
Humidifier that uses hygroscopic element to increase surface contact with gas.
Wick humidifier
Types of suction devices?
Yankauer (gentle curve to fit aiway) Self suction catheters (inserted in tube)
Is HME better than a bubble humidifier?
Yes, but not nearly as good as a wick
Why do we do a 2 point calibration on the Oxygen Analyzers?
You need to be able to tell if you are running out of current activity.
ultrasonic neb the flow of gas is determined by
a built-in blower that delivers room air to the solution chamber
hypoxia (again...)
a deficiency in either the delivery or utilization of oxygen at the tissue level
humidifier
a device capable of adding water to gas as water vapor
for SA, the simplest method is to use direct gas over
a large reservoir of water
What is a tracheostomy tube?
a surgical incision into the trachea
the vibrations (created by piezoelectric transducer) are transmitted to
a tap water bath
hydrophobic condenser uses
a water-repellant element with a large surface area and low thermal conductivity
What is the primary indication for lung inflation therapy? 1. to prevent atelectasis 2. to prevent hypoxemia 3. to reverse hypercapnia 4) to reduce pulmonary shunting a) 1 only b) 1 and 2 only c) 2 and 3 only d) 1,2,3, and 4
a) 1 only to prevent atelectasis
The active drug component of typical pMDI accounts for what percentage of the total content of the mixture in the device? a) less than 1% b) 10% c) 25 % d) 60%
a) less than 1%
Bland Aerosol Therapy Equipment
a. Large Volume Jet Nebulizers b. Ultrasonic Nebulizers (USNs)
_______ contraindication would be NO ultrasonics for infants
absolute
Humidifier
adds molecular water to gas via evaporation from water surface
What are the ETT tube sizes?
adult male- 8.0-9.0 adult female- 7.5-8.5 newborn to teenager- 2.5-6.o
what are the ventilation rates during CPR?
adult: 10 bpm child:8-10 bpm infant: 8-10 bpm
Polarographic Analyzer: Obstruction of the membrane, as with _________ droplets, can cause an erroneous reading.
aerosol
Goals of humidity and aerosol therapy
aid in bronchial hygene, humidfication of inspired gas, and deliver medications
goals of humidity and aerosol therapy
aid in bronchial hygiene, humidification of inspired gas, deliver medications
Variable air entrainment port allows
air mixing to increase flow rates and vary FIO2
What are the absolute contraindications for a double lumen ETT?
airway mass that may be occluding, dislodged, traumatized or hemorrhaging
what is humidity?
amount of water vapor in a gas
Humidity deficit
amount of water vapor that must be added to a gas to acheive 100% humidity at a specific temp
What is the humidity deficit?
amount of water vapor that must be added to achieve 100% humidity at a specific temp
the dial on the front of the ultrasonic controls the _______ of the piezoelectric transducer
amplitude
jet reservoir is also known as a(n)
aquapak humidifier
The optimum range of aerosol particle sizes that are to be inspired for general deposition through the upper and lower airway is: a) o.1-1 um b) 1-5 um c) 3-10 um d) 5-15 um
b) 1-5 um
What types of percussive pressure does the Percussionaire IPV device deliver? a) 10 to 20 cm H20 b) 25 to 40 cm H20 c) 50 to 100 cm H20 d) >200 cm H20
b) 25 to 40 cm H20
Based on the AARC Clinical Practice Guideline, the temperature of medical gas delivered through an artificial airway should be: a)20-25 degrees Celsius b)31-35 degrees Celsius c)36-40 degrees Celsius d) over 45 degrees Celsius
b) 31-35 degrees Celsius
What is the recommended gas flow rate to operate an SVN? a) 1 L/min b) 6 to 8 L/min c) 10 L/min d) 15 L/ min
b) 6 to 8 L/min
If the temperature of a saturated gas decreases, which of the following occurs? a) condensation develops b) absolute humidity increases c) relative humidity increases d) water vapor pressure increase
b) absolute humidity increases
Mechanical insufflation-exsufflation therapy has been shown to be most effective in patients with: a) croup b) duchenne muscular dystrophy c) asthma d) Acute respiratory distress syndrome
b) duchenne muscular dystrophy
Which of the following parameters is used to set the therapeutic goal for a patient using a volume-displacement incentive spirometer? a) total lung capacity b) inspiratory capacity c) inspiratory reserve volume d) expiratory reserve volume
b) inspiratory capacity
What is the most important factor influencing aerosol deposition from an MDI? a) tidal volume b) inspiratory flow rate c) respiratory rate d) breath-hold
b) inspiratory flow rate
Which of the following results in increased aerosol deposition? a) large tidal volume b) slow inspiratory flow rate c) decrease in the expiratory peak flow d) short expiratory times
b) slow inspiratory flow rate
why is it especially important in newborns to maintain humidification?
babies don't have any reserve
some hydrophobic HMEs provide
bacterial filtration
some hydrophobic HMe;s provide
bacterial filtration
Jet Nebulizer: Fluid is then accelerated by the jet into a ______ where it is broken into an aerosol where it exits the patient ports.
baffle
Aerosols are accelerated into _______ to break particles into smaller sizes.
baffles
How do you check if the combitube is inserted correctly?
bag blue tube first if no air it's in the trach and if there's air it's in the esophagus bag white tube if it's in the trach
How much do you preoxygenate the patient in ET intubation?
bag with 100% oxygen
If you have a pt that is prone to bronchospasm
be especially care! and pre tx with a bronchodilator first.
Why do neonatal tubes typically not have a cuff?
because of their small diameter of their airway
Heated aerosols cool as they travel down the respiratory tract and then....
become larger then deposited into the larger airways
What are the 2 types of oropharyngeal airway?
berman guedel
uses what principle
bernoullis
How do you displace the epiglottis with a Miller's?
blade tip goes under epiglottis to directly lift and visualize glottis
How do you displace the epiglottis with a Macintosh?
blade tip into vallecular notch indirectly lifting it to visualize glottis
Pulse oximeters cannot read accurately when there is massive ____loss
blood
how do you check for the proper placement of an oropharyngeal airway?
by assessing their breathing
any patient whose upper airway is ________ needs to be heated as well as humidified
bypassed
when the upper airway has been _______ or is insufficient, aerosol therapy is necessary to assure humidification of inspired gas
bypassed
If a patient has an artificial airway in place, what should be the minimum level of absolute humidity provided to the patient's airways? a) 10 mg/L b) 20 mg/L c) 30 mg/L d) 40 mg/L
c) 30 mg/L
According to the manufacturer, what is the flow of gas from a Vortran IPPB device connected directly to a 50-psig gas source? a) 10 L/min b) 25 L/min c) 40 L/min d) the flow varies as the amount of gas entrained by the patient changes
c) 40 L/min
A sample of room air gas contains 10 mg/L of humidity. What is the RH of gas if the room temperature is 77 degrees Fahrenheit? a) 10% b) 22% c) 43% d) 98 %
c) 43%
Under normal respiration, the humidity in the trachea is around
can range from 36 mg/L to 40 mg/L and the optimal required moisture below the carina is 44 mg/L (100% relative humidity [RH] at 37°C).
total amount of water that can be held by a gas at a specific temperature
capacity
How do you determine the humidity deficit?
capacity - content
When temperature goes up is has the ability to hold more
capacity ie: water vapor and vice a versa via condensation
The wick draws water into the honey comb like structure by means of
capillary action
If a person on a HME has lots of secretions what do you do?
change them to a heated humidifier (COPD) wick or membrane type
Question 24 If a person on a HME has lots of secretions what do you do?
change them to a heated humidifier (COPD) wick or membrane type
HME troubleshooting: if a patient is having mucus plugs or increased thickness of secretions...
change to heated moisture.
If you have no mist with an SVN, you should?
check flow, check for connections, or check for medication
What is the mucociliary response?
ciliated epithelial cells goblet cells basal cells submucosal glands
whenever using a heated humidifier the temperature must be
closely monitored to prevent airway hyperthermia
What does huff coughing do?
closes glottis, which increases pressure
What are dendrite cells?
collect info on viruses/ bacteria and activate immune responses
HME mode of operation
collects moisture from patient's exhaled air
Mode of Operation with using a HME
collects moisture from pt's exhaled air
relative Humidity
comparison of the actual content of water vapor in a gas, to the amount it could hold if it were 100% saturated
during exhalation, some water is
condensed on the cool condenser element, other molecules bind to the salt
What is a bubble humidifier?
connected to a flowmeter, dry gas is directed down a capillary tube. gas stream exits tube and forms bubbles. the bubbles gain humidity as they rise to the surface 10-20mg/L 1-6LPM pressure valve at 2psig
Metered Dose Inhalers (MDI) requires proper medication mixing to deliver a ______ dose.
consistent
What is bland aerosol?
consists of liquid particles suspended in gas (O2 or air)
nebulizing unit
contains a Piezoelectric transducer which transforms the ultra high frequency electric current into ultra high frequency vibrations
Evaporation a (heating/cooling) process.
cooling
The AARC Clinical Practice Guideline for IPPB states that this form of therapy is a viable lung expansion technique for patients with reduced lung function. Which of the following findings from a patient suggest that IPPB is warranted? 1) FVC = 50% predicted 2) FEV1=70% predicted 3) MVV<50% predicted 4)VC=15 ml/kg a) 1 only b) 4 only c) 2 and 3 only d) 1 and 3 only
d) 1 and 3 only FVC = 50% predicted MVV<50% predicted
Which of the following are contraindications to the administration of IPPB? 1. active hemoptysis 2. nausea 3. intracranial pressure >15 mm hg 4. recent esophageal surgery a) 1 and 3 only b) 2 and 3 only c) 1,2, and 3 only d) 1,2,3, and 4
d) 1,2,3, and 4 1. active hemoptysis 2. nausea 3. intracranial pressure >15 mm hg 4. recent esophageal surgery
Which of the following are potential problems that may arise in patients with a tracheostomy who are breathing nonhumidified oxygen at a rate of 6L/min? 1. atelectasis 2. destruction of the airway epithelium 3. inspissation of secretions 4. mucociliary dysfunction a. 1 and 3 only b. 2 and 4 only c. 1,2, and 3 only d. 1,2,3, and 4
d) 1,2,3, and 4 Atelectasis Destruction of the airway epithelium inspissation of secretions mucociliary dysfunction
Which of the following are considered positive outcomes to PEP therapy? 1. increased sputum production 2. increased respiratory rate 3. resolution of hypoxemia 4. Diminished breath sounds become adventitious sounds that can be auscultated over the larger airways. a) 1 only b) 1 and 3 only c) 2 and 3 only d) 1,3, and 4 only
d) 1,3, and 4 only 1. increased sputum production 3. resolution of hypoxemia 4. Diminished breath sounds become adventitious sounds that can be auscultated over the larger airways.
A gas at body temperature and ambient pressure (BTPS) contains: a) 10 mg/l of water vapor b) 30 mg/l of water vapor c) 33.9 mg/l of water vapor d) 43.9 mg/l of water vapor
d) 43.9 mg/l of water vapor
The function of the steel ball in the Flutter device is to: a) help prevent early airway closure b) provide high-frequency oscillation c) create a positive expiratory pressure d) all of the above
d) all of the above a) help prevent early airway closure b) provide high-frequency oscillation c) create a positive expiratory pressure
Which of the following is classified as a passive humidifier? a) bubble humidifier b) ultrasonic nebulizer c) wick humidifier d) heat and moisture exchanger
d) heat and moisture exchanger
high flows ? contact time
decrease
shallow column=
decreased contact time
shallow column ? contact time
decreases
In order to use a Passy Muir Talking Valve what must you do first?
deflate the trach tube's cuff (so air can be exhaled) no food while cuff is deflated
what is the simplest method for surface area
direct gas over a large reservoir of water
bubble diffusion humidifiers
directs a stream of gas under water were it broken up into tiny bubbles - smaller the bubble greater water/air surface ratio
simple reservoir
directs gas over water surface used heat w/mechanical ventilation use room temp nasal CPAP and BPAP
The supplied gases must be filtered and ________.
dry
membranes separate water from
dry gas stream by a means of hydrophobic membrane
when is sputum induction best?
early a.m.
What are the advantages of a Nasal ETT?
easier to stabilize and suction better tolerated no bite block needed less risk of trauma to larynx during insertion
Mode of operation with an Ultrasonic
electric
mode of operation for ultrasonic
electric
ultrasonic nebs
electriclaly powered
Transcutaneous Monitor uses the skin as an _________ membrane.
electrode
Continuous monitors look at the CO2 value at the ______ of exhalation, called the end-tidal CO2, or PetCO2.
end
What are the steps of extubation?
ensure equipment for reintubation is available suction airway deflate cuff & remove tube at peak inspiration suction mouth and have patient cough after extubation apply oxygen observe for complications (check for stridor)
What is a tracheal fistula?
erosion of the tracheal wall tissue into the esophagus leads to frequent aspiration rare but can erode into artery which is usually fatal high cuff pressure is main causative factor
All humidifiers work by the principle of ______________.
evaporation
decreased pressure causes an increased __________
evaporation
Heat & Moisture Exchangers capture
exhaled heat and moisture and use it to heat and humidify the next inspiration (Does not add heat and water to the system)
captures about 50 % of pts
exhaled moisture
airways narrow on?
expiration
removal of an ETT is known as?
extubation
Polarographic Analyzer: Has an additional power source, therefore response time is _________.
faster
Gas and water are in contact only at the ____________ of the water.
fetch
Hygroscopic Condenser's material is
filled with hygroscopic salt -Captures moisture from exhaled gas
hydrophobic also act as
filters
Why would we use a SPAG?
for RSV to deliver Riboviran
Aerosol droplets are
foreign particles
What makes up the nasal cavity and nasopharynx?
formed by union of facial bones lined with mucous membranes, cilia tissues are delicate, vascular adenoids/lymph tissue- filters bacteria (commonly infected)
what affects the contact time
gas flows
what is a result of vapor pressure?
gas temp and relative humidity
vapor pressure is a result of
gas temperature and relative humidity
what is an aerosol?
gaseous suspension of liquid particles
what is a passover humidifier?
has no cascade/grid uses heated plate instead of rod still provides 100%humidity less humidification output because gas passes over the hot water
anhydrous
has no humidity whatsoever so it can be very dry
What is the basic insertion procedure for a combitube?
head is in neutral position open mouth and press away tongue flat insertion along tongue inflate proximal cuff to 85-100ml inflate distal cuff to 10-15ml
what are two ways to open and clear the airway?
head tilt/chin lift or jaw thrust suction airway with yankauer, bulb, or flexible suction catheter
HME's capture exhaled heat and moisture and use it to
heat and humidify the next inspiration
HME's do not add
heat and water to the system
HME
heat moisture ex-changer (also called artificial nose)
trach or an ET tube needs to be _______
heated
What are the functions of the upper airways?
heating and humidification nose, sinuses, trachea, bronchi
What do new passover humidifiers have?
heating water in a chamber and a heated breathing circuit reduce rainout
indications of aerosol therapy
high flow O2 delivery, need for medicine delivery, and bypassed upper airway
indication for humidity and aerosol therapy
high flow oxygen delivery, need for medication delivery, bypassed upper airway (they have ET tube or trach)
what type of system is a non-rebreathing face mask?
high flow system
large volume neb has liquid particles generated by passing gas at a
high velocity through a small jet orifice
what are the 2 purposes of the inflated cuff of an esophageal obturator?
hold the tube in the esophagus seal off esophagus below cuff which prevents air from entering the stomach
HIS
hospital information system -large scale multi user database management system
4 Types of Heating Elements in heated humidifier systems
hot plate, wraparound, yoke or collar, immersion
4 types of heating elements
hot plate, wraparound, yoke or collar, immersion
device capable of adding water to a gas as water vapor
humidifier
primary indications of humidity therapy
humidify dry medical gases, overcome the humidity deficit created when the upper airway is bypassed
Aerosol Therapy Objectives: To treat/prevent a ___________ deficit.
humidity
Faster air means a decrease in?
humidity
more and or smaller bubbles and increased time exposure will increase ______
humidity
What can improper temp and humidity of inspired gases lead to?
hypothermia inspissation of secretions atelectasis (plugs close the airway)
Troubleshooting of a jet reservior
if a flow meter is set to high water will collect quickly in the tubing
pathophysiology of histotoxic hypoxia
inability of cells to utilize oxygen
low flows ? contact time
increase
variable air entrainment port allows air mixing to
increase flow rates and vary fIo2
Many lung diseases cause mucus to?
increase its viscosity and elasticity
breathing treatment: if there is no mist
increase the flow, check for connections, and check for medication
symptoms to look for with swelling of dry, thick secretions
increased WOB, SOB, increased HR, increased RR, decreased Sat., acc. muscle usage, and wheezing bc of partial obstruction caused by plugging
deeper column=
increased contact time
symptoms of patients with swelling of dried retained secretions
increased dyspnea and SOB, labored breathing, possible retractions (sternal, suprasternal, or intercostal), and increased respiratory rate
pathophysiology of demand hypoxia
increased oxygen consumption
contraindications of HME;s
increased secretions, thick dehydrated secretions, hypothermia, large tidal volumes, small tidal volumes with large-volume HME's, during aerosol therapy, with heated humidification, airway leaks around a artificial airway
increased heat means
increased water used
deeper column ? contact time
increases
doubling the radius of a tube does what to resistance?
increases it by 16x
If absolute humidity is constant, ___________ temperature,_________ relative humidity Why?
increases, decreases Because of the increase of the gas' ability to hold water
fluid overload is a problem for _______
infants
What is endotracheal intubation?
insertion of artificial airway into patient's airway
Airways expand on?
inspiration
if a patient is breathing 24 times a minute, they are going to have a high _______
inspiratory flow
How much CO2 is in inspired gas and end-tidal gas?
inspired gas: .04% end-tidal: 6%
What does prolonged administration of dry gas cause?
inspissated mucus (thickened, dried) increased mucus reduced ciliary activity is reduced cell damage
aerosols with surface area is
instead of dispersing gas in water, we disperse water in the gas
sterile water
is great for sputum induction
the frequency on an USN
is set at the factory so we can't control it
Heat and moisture exchange:
is the primary function of the upper respiratory tract; mainly the nose. Nose: heats and humidifies gas on inspiration and cools and reclaims ≅water from gas that is exhaled.
Many systems have a reservoir feed system that
keep the water at a constant level
Jet Nebulizer: Baffles are placed in the path of the gas to knock out ________ particles, producing an aerosol with particles of more uniform, desired size.
larger
What makes the pediatric airway different?
larger tongue in proportion to mouth floppy epiglottis delicate teeth&gums narrowest point is at cricoid ring younger than 8yrs old funnel shaped larynx due to undeveloped cricoid cartilage
aerosol devices
larger volume neb, ultrasonic neb
What percentage of a cuff leak means that the patient is at risk for stridor or reintubation?
less than 10%
Laminar flow occurs with flow rates of....
less then .5L/sec
bland aerosol therapy consists of
liquid particles suspended in a gas, which is unlike humidity when water is in gaseous state
Upon visual inspection, there would be no
liquid water in the humidifier chamber
upon visual inspection with a membrane passover humidifier there would be no
liquid water in the humidifier chamber
In Respiratory Care, we most frequently aerosolize ______.
liquids
What are the 2 categories of humidifiers?
low flow high flow
what type of system is the simple face mask?
low flow system
A capnograph generally reads levels _______ than PaCO2 values.
lower
advantages to bubble humidifiers
maintain saturation at high flows, add little or no flow resistance to spontaneous breathing circuits, don't generate micro aerosol particles
Convection, evaporation, and rehydration are used to?
make sure the gas is humidified for the lower airway
What is a Jackson trach?
metal trach cuffless long term airway access
absolute humidity is expressed as
mg of H2O/L of gas
Hygroscopic condenser humidifier(HME)
more efficient due to: -retain heat due thermal conductive material -hydroscopic salt captures extra moisture - 70%
what are the disadvantages of a Nasal ETT?
more painful and frequently causes bleeding during insertion possible necrosis of nasal passage possible obstruction of sinus drainage
the temp change results in
more water being conserved to be used in humidifying the next breath
Temperature is the
most important factor affecting humidifiers
Polarographic Analyzer: Can also be used to analyze gas that is in _________.
motion
increased humidity can help restore or maintain the ________
mucosal blanket
increasing humidity can help retore or maintain the
mucousal blanket
what is the gel layer?
mucus layer that covers the sol
you'll see bubble diffusions with
nasal cannula's, or small humidifiers
total occlusion
no breath sounds, increased HR, decreased sat
Contraindications for humidification
no contraindications to providing physiologic conditioning of inspired gas during mechanical ventilation.
What is a single cannula tracheostomy tube?
no inner cannula disposable
what is rainout?
occurs when warm, moist gas exits a cascade, wick, or passover humidifier and enters the patient circuit this happens because the gas cools as it moves through the tubing and becomes liquid
Who performs endotracheal intubation?
often times only by anesthesia dept, ER physicians, residents, etc. due to requiring frequent practice to maintain the skill versus how low the number of intubations are performed in a hospital
large particles fall
out of suspension
heated humidifiers always
outperform unheated ones
Which method of monitoring the cuff should we not use?
palpation of cuff-feeling cuff with fingers to determine firmness
Jet Nebulizer: These nebulizers produce less uniform size _______.
particles
what are the types of high flow humidifiers?
passover cascade wick heated wire circuit membrane cartridge system high flow bubble HME
Who should NOT use a HME booster?
pediatric and infant patients
ultrasonic nebs use what to generate an aerosol
piezoelectric crystal
What is a diffuser humidifier?
plastic or metal diffuser at end of capillary tube which increases the number of bubbles 10-20mg/L 1-6LPM
Mode of action of a jet reservior
pneumatic
Mode of operation for a jet intermittent
pneumatic
USN has 2 components
power unit and nebulizing unit
ultrasonic has two components
power unit and nebulizing unit
A SPAG has 2 flow meters inside unit that
powers the drying unit (makes paricles smaller), and powers the flow to pt
nebulizer
produces an aerosol
Continuous Med Nebulizers are used to give ___________ medications to patient not responding to single dose neb administration.
prolonged
what is the power stroke?
push mucus in one direction bends backward then pushes forward
how can an OAW that's too short cause complications?
pushes tongue into airway
Disposable CO2 Detectors is a ____ measurement
qualitative
What are the 2 types of a needle cricothyrotomy ?
quick trach pertrach
In the power unit of an USN it....
receives standard alternating current and converts it to a ultra high frequency which is conveyed to nebulizing unit
power unit
receives standard alternating current and converts it to ultra high frequency which is conveyed to the nebulizing unit
pathophysiology of hemic hypoxia
reduced hemoglobin content and/or function
Heating systems have a controller that
regulates the temp
bronchospasm is a ______ contraindication (not a reason not to give humidity or aerosols but just be aware of it; pretreat)
relative
comparison of the actual content of water vapor in a gas to the amount it could hold if it were 100% saturated
relative humidity (equation: RH=content/capacity)
What is decannulation?
removal of a tracheostomy tube by making the tube smaller and smaller
What is extubation?
removal of artificial airway
Polarographic Analyzer: The fuel cell must be _________ periodically.
replaced
only use an HME short term for
replacement of moisture for bypassed airway
there is a _______ at the end of a breathing treatment that will not nebulize
residual volume
What are the contraindications of a Nasal ETT?
resistance in nares patients with blood clotting or anticoagulation problems
humidity therapy
respiratory therapy that delivers water vapor or aerosol.
What was an ETT originally made of?
reusable flexible rubber
During a cough, the airflow does what?
rises while the airway narrows which increase the shearing forces which create a toward the head airflow
what is a HCHF?
same as HCH but with a thin bacterial filter
List non technical application for computer usage in hospital
schedules, billing
HME uses
short-term replacement of moisture for a bypassed airway (can cause mucus plugs from not having enough moisture)
When and who should be handling the tracheostomy tubes?
should be done by a surgeon should only be changed as needed (if infection occurs or the airway isn't functioning properly)
how should the face mask for a bag-mask system fit?
should fit over the bridge of the nose, cheeks, and chin to produce an airtight seal
how do you deflate and inflate the LMA?
slowly deflate cuff to form smooth flat wedge shape which will pass easily around the back of tongue and behind epiglottis
bubble diffusion creates
small bubbles to increase surface area
uses for an ultrasonic
sputum induction
bland aerosol therapy involves the delivery of
sterile water or hypotonic, isotonic, or hypertonic saline solution Often used in conjunction with oxygen therapy
if pt has any symptoms from using USN
stop tx, notify doc or nurse, and pre tx nxt time with bronchodilator
What is a Miller laryngoscope?
straight tip blade displaces the epiglottis directly by advancing the blade over its posterior surface and lifting up and forward (lifting lid off of glottis)
The ____________ of the current is directly proportional to the amount of oxygen present.
strenght
large particles fall out of
suspension
aerosol
suspension of liquid or solid particles in a gas
hazards of humidity and aerosol therapy
swelling of dried retained secretions, precipitation of a bronchospasm, fluid overload, cross contamination
What could happen if you put a pt on 6cc on USN and they have alot of dry, thick secretions?
swelling of dry, thick secretions
Hazards of aerosol therapy
swelling of dryed, retained secretions, parcipatation bronchospasm, fluid overload, and cross contamination
What is the most effective method to improve the characteristics of pulmonary secretions?
systemic hydration (drink water)
changes in room temperature cause humidity to fall out or rain into jet reservoir tubing; if this happens you need to
take the tubing off and "milk" it into a trash can (NEVER dump water back into the reservoir)
closed loop
takes action : ventilators
conscious patient
talking, swallowing, etc.
Ultrasonic Nebulizers (USN) The couplant chamber is filled with _____ water.
tap
nebulizing unit vibrations are transmitted to a
tap water bath
How do you secure the tube?
tape or commercially prepared holders
What makes up the oral cavity and oropharynx?
teeth tongue (most common cause of airway obstruction) palate (anterior=hard, posterior=soft) tonsils (commonly infected) epiglottis (prevents aspiration) vallecula (pocket)
The nose and mouth have what temp and humidities?
temp 20-22 RH: 50% AH: 10mg/L
Below the IBS
temp and relative humidity remain constant thus achieving BTPS
Body Humidity
the capacity at 37C is 44 mg/L of gas
The Piezoelectric transducer sits in this bath called?
the cuplet
Dry drowning is caused by?
the defense reflex of bronchconstriction to prevent H2O inhalation or smoke
water accumilates in
the dependent portion of the large borr tubing
Contact time depends upon
the depth of the water column
the longer the gas remains in contact with water...
the greater the amount of evaporation
The greater the temperature of the gas
the greater the amount of water vapor it can hold
the greater the temperature of the gas ...
the greater the amount of water vapor it can hold
The greater the area of contact between the water and the gas
the greater the evaporation
relative humidity
the ratio of the actual amount of water vapor present in a gas compared to the max amount of water vapor that the gas can hold at a given temperature. expressed as a percentage
low pressure at the jet draws fluid from
the reservoir up to the top of the siphon tube
What are shearing forces?
the sudden separation of mucus from the bronchial wall as a result of {rapid, forceful outward airflow} =cough
Whenever using a heated humidifier
the temperature must be closely monitored to prevent airway hyperthermia
How does time affect evaporation and resulting absolute humidity?
the time that gas is exposed to all of these factors will increase humidity.
Narrowing the airways causes?
the velocity and shearing forces to increase
signal amplitude alters
the vibrational energy and directly affects the quantity of aerosol produced
what happens to mucus during a cough?
the viscosity is reduced allowing easier transportation
If pt coughs any sputum in the HME, you should....
throw away and replace
any pt that has upper airway bypassed needs
to be heated
The delivery of cool humidified gas is used to
treat upper airway inflammation from croup, epiglottitis, post extubation edema *this is used in conjunction with bland aerosol
How is the esophageal obturator designed?
tube is a sealed ETT which has perforations along it and a cuff at the tip obturator is inserted into esophagus and cuff is inflated
what are the two ways to insert an oropharyngeal airway?
upside down and turn around start at 90 and twist
to prevent rain out:
use a heated wire circuit in the tubing to keep the temperature throughout the tubing constant
What do you use to maintain a patent airway?
use an artificial airway
advantages to HME's (3)
use standard connections, have a low compliance, add minimal weight, dead space, and flow resistance to breathing circuit
Name a device that will give a specific percentage of oxygen regardless of the patients respiration's and Vt
venturi mask
warm air can hold
warm moisture
partial occlusion
wheezing, increased HR, decreased sat
symptoms of swelling of dry, retained secretions
wheezing, increased dyspnea, SOB, labored breathing, possible retractions, and increased resp. rate
how does ventilation occur in an esophageal obturator?
when air is forced into tube from bag/mask the air travels down the tube and exits at perforations into the airway
Indications for humidification
- Humidification of inspired gas during mechanical ventilation is mandatory when an endotracheal or tracheostomy tube is present, but optional with NIV. 1. Primary a. Humidification of dry medical gases b. Overcoming the humidity deficit created when the upper airway is bypassed 2. Secondary a. Managing hypothermia b. Treating bronchospasm caused by cold air
Bland Aerosol Therapy
- Humidification therapy using inspired gas consisting of water, saline solution, or other substances without important pharmacologic action - used primarily to humidify, liquefy, or otherwise change the character of thick secretions.
passover humidifier
- Humidifying device that directs gas over the surface of a body of water; an example is the passover wick humidifier; or over a wick or membrane - Gas passes over the surface of H20, picking up moisture
What are the solutions used in humidity therapy ?
- Hypertonic - Isotonic - Hytpotonic
What is water vapor pressure ?
- It experts a pressure as part of the atmospheric pressure - Dalton's Law of Partial Pressures
What is overhumidification ?
- Leads to excess body fluid retention - Efficiency of cilia is decreased - Dilutes surfactants and collapsed alveoli - Swelling of mucous layer and causes narrowing of air passages
What is servo control ?
- Many modern ventilator circuits maintain a "water free" tubing with a feedback servo system that keeps the temperature constant - Recommended temperature ranges 34-35*C even 37*C
What is upper airway stridor ?
- Narrowing of the neck breathing passages - Caused by swelling of inner lining - Cool temperature causes decreased swelling and increase size opening - Croup/post extubation
Advantages of Passover Humidifiers
- Passover humidifiers can maintain saturation as high flow rates. - Add little or no resistance to spontaneous breathing circuits - The do not generate aerosols and therefore pose minimal risk for spreading infection
When do you use a heated humidifier ?
- Patient is on long term vent - HME doesn't work
Question 29 What problems does condensate in a ventilator circuit pose for mechanically ventilated patient?
-Can impair gas flow through circuit May effect ventilator function -condensation may be aspirated by patient Circuits must be pointed to drain condensate away from patient Check often, excess condensate must be drained from circuit -Patients contaminate circuits within hours which becomes colonizes with bacteria and thus poses an infection risk -Breathing circuit condensate should be treated as infectious waste
What are different memory devices?
-Internal memory: immediately available to CPU -External memory: Provided by mass storage devices such as disk drives -Memory is the electronic space where computer's store data or instructions
What are the clinical signs and symptoms of inadequate airway humidification?
-atelectasis -dry, non productive cough -increased airway resistance -increased incidence of infection -increased work of breathing -Patient complaint of substernal pain and airway dryness -Thick. dehydrated secretions
3 primary types of humidifiers
-bubble -passover (three types) ~Wick, simple reservoir, and membrane -HME (two types) ~active type:actively add heat & or water device ~passive type: recycling heat and humidity from pt
What are the indications of a tracheostomy tubes?
-bypassing upper airway obstruction thus maintaining a patent airway - facilitate removal of secretions -permit long term positive pressure ventilation -prevent aspiration of gastric contents -congenital defects -improve patient comfort due to absence of ETT -decrease WOB and increase volume entering lungs by reducing anatomical dead space
what are the risks with rainout?
-contamination of lower RT from aspiration or lavage from circuit rainout may cause more infections -water traps are used to collect it and remove it routinely
hazards are greater breathing cold, dry gas with artificial airway cause?
-damage tracheal epithelium within mins - prolonged breathing cause hypothermia, thickened secretion, damage epithelium, mucociliary dysfunction and atelectasis -humidity 60% at BTPS no damage to lungs
4 most common causes of preoperative hypoxemia
-decreased PAO2 (V/Q mismatch, hypoventilation) -shunt -decreased mixed venous O2 -diffusion defect
What are the indications for a Combitube?
-definitive airway management cannot be obtained via ETT -often last resort
What are the disadvantages of a double lumen ETT?
-distorted tracheal anatomy may cause it not to be positioned adequately -traumatic injury to airway during insertion or removal of tube -tracheal or bronchial tissue necrosis due to excessive pressure in cuffs
Question #20 heated wick humidifier
-draws water like sponge honeycomb structure by capillary action - gas pass through or next wick evaporation to occur -addition of heat ,high humidity achieved 90%+
complications of NAW
-esophageal intubation -laryngospasm -vomiting (less likely than OAW) -nasal mucosa injury and secondary blood aspiration
unconscious patient attempting to breathe but airway is obstructed
-maintain O2 -airway support -assistance for breathing
unconscious patient with neuromuscular blockade
-maintain O2 -positive-pressure ventilation
indications for an OAW
-maintenance in sedated and unconscious patient -protects ETT from being bitten and occluded -facilitates airway suctioning
characteristics of resuscitation face masks
-malleable, transparent body -22 mm connection -air-cushion seal -no retaining ring
Question #7 secondary indication of humidification
-manage hypothermia - treat bronchospasm caused by cold air
Basic Aim for humidification?
-meet or exceed the water vapor content found in room air -American National Standard Institute(ANSI) id 10mg/L water vapor content as minimum level of absolute humidity avoid mucosal damage to upper airway -equal to 50% relative humidity and 23C and 72F - bubble humidifier meet this level of humidification and more
O2 therapy for more stable patient
-mild to moderate hypoxia low to moderate Oxygen concentrations. Stable FIO2 not necessary nasal cannula at moderate flow or simple mask -common examples: immediate post op patients or acute MI
Therapeutic Gases
-most commonly used humidification O2 pt w/normal airway - pt need supplement humidification: systemic dehydration abnormal production secretion(COPD)
Question #14 temperature effects humidifiers performance?
-most important factor that affects level of humidity -the greater the temp. of gas the more water vapor it can hold(^ capacity) - evaporation cools the temp. of gas ability to carry water vapor. ~temp gas leaves humidifier less than room air ~humidity output less saturated air at ambient temp -simple solution heat the humidifier.
HME basic operation
-passive humidifier -artificial nose ~like nose capture exhaled moisture and heat use next inspiration ~unlike nose dont actively add heat and water -return 70% moisture - used for machenically ventilated and spontaneously breathing pt & long term use
what are the indications for a heated high flow nasal cannula?
-patient's requiring high flows who are currently on venti masks, non-rebreathers, or need a high flow but can't use mask -tracheostomy patients who may require higher flows and/or heated, humidified gas -COPD and asthma or bronchiolitis patients -patients who required hydration of thickened secretions -non-intubated patients who require re-warming from a hypothermic state
what are the contraindications for heated high flow nasal cannula?
-patients who are obtunded -patients unable to control their airway -patients with severe respiratory acidosis (^CO2, not breathing enough, need deeper breaths) -patients with suspected facial fractures or skull fractures
Question # 20 wick passover humidifier
-porous water absorbent material ^ surface area -cylinder absorbent materials placed upright water reservoir surrounded by heat ~gas go into the chamber picks up moisture and leaves the chamber fully saturated with water vapor ~used on pt bypassed airway who mechanically ventilated ~no bubble or aerosol produced ~most common humidification mechanically ventilated -surface of wick ^ area contact between water/gas
what can be used to control an airway?
-positive-pressure ventilation -negative-pressure ventilation
*Cool,* humidifiers used to treat
-post extubation edema -airway inflammation -croup -epiglottitis -upper airway swelling -used w/ bland aerosol delivery (P.A.C.E. U.U)
humidity therapy 3 function
-primary goal maintain physiological condition of lower airway -assuring normal function of mucociliary transport -supplying increased levels of water vapor to inspired gas
pathophysiology of circulatory hypoxia
-reduced cardiac output -microvascular dysfunction
what are the hand-operated bag-masks?
-self-inflating Ambu bag -anesthesia circuit and bag
clinical examples of circulatory hypoxia
-severe heart failure -dehydration -sepsis -SIRS
3 types of face masks
-simple -partial rebreathing -nonrebreathing
what can you do with NAW if there is resistance when trying to insert it?
-slight tube rotation -try other nostril
aerosol nebulizers
-spray water particles into stream of gas -higher the aerosol density the greater surface area
inspissated
-thicken due to dehydration(thick or congeal) -breathing dry air
What is the correct ETT position?
-tip of tube should be 2cm above carina -CXR determines actual position -tube markings give approx correct position -orotracheal tubes should be 21cm deep for females and 23cm for males
how is an OAW inserted?
-tongue depressor pulls tongue forward -OAW goes in upside-down and rotated 180 degrees
what are high flow humidifiers?
-used with high flow O2 -should provide patient's total needs (i.e. body humidity)
what is a HCH?
-uses low thermal conductive material that has been treated with a hygroscopic chemical -as exhaled gas passes through the device, water particles are formed as the gas comes in contact with the cool surface area of the condenser element -water particles remain liquid until inspiratory gas passes through the unit, water molecules are released to humidify the gas
What are alveolar macrophages?
engulf particles and destroys them (phagocytosis)
How do you lubricate the LMA?
-water soluble lubricant -lubricate just prior to insertion and lubricate the back of mask thoroughly -avoid excessive amts of lubricant on anterior surface of cuff or in the bowl of the mask -inhalation of lubricant following placement could cause coughing or obstruction
What is tracheomalacia?
-weakness and floppiness of the walls of the trachea causing airflow obstruction -caused by prolonged intubation or high cuff pressures (can also be congenital) -not realized til after tube is removed and rarely seen -in rare cases tracheal stents are inserted
FIO2 range of a simple mask with a flow rate of 7-8 L/min
0.40-0.60
FIO2 range of a nonrebreathing mask-bag
0.40-1.00
What percentage is half NaCl Solution?
0.45%
FIO2 of a venturi mask and jet nebulizer with a flow rate of 8-12 L/min and total flow of 33
0.50
FIO2 range of a partial rebreathing mask-bag with a flow rate of 15 L/min
0.65-1.00
What is the portion that is supplied by the humidifier in terms of moisture input?
0.75 x 44 mg/L = 33 mg/L
Normal Saline = ______% NaCl
0.9%
What percentage is Isotonic (normal) NaCl solution?
0.9%
Particles which are < ___ are almost unaffected by gravity.
1
Particles which are < _____ µ are generally inhaled and exhaled without depositing in the lungs.
1
Particle sizes between one and five microns (____µ - ____ µ) are clinically optimal for peripheral deposition in the respiratory bronchioles.
1 - 5
what is the output for an ultrasonic?
1-6 ml/min
Recommendations for humidification during invasive and noninvasive mechanical ventilation.
1. Humidification is recommended on every patient receiving invasive mechanical ventilation. 2. Active humidification is suggested for noninvasive mechanical ventilation, as it may improve adherence and comfort. 3. When providing active humidification to patients who are invasively ventilated, it is suggested that the device provide a humidity level between 33 mg H2O/L and 44 mg H2O/L and gas temperature between 34°C and 41°C at the circuit Y-piece, with a relative humidity of 100%. 4. When providing passive humidification to patients undergoing invasive mechanical ventilation, it is suggested that the HME provide a minimum of 30 mg H2O/L. 5. Passive humidification is not recommended for noninvasive mechanical ventilation. 6. When providing humidification to patients with low tidal volumes, such as when lung-protective ventilation strategies are used, HMEs are not recommended because they contribute additional dead space, which can increase the ventilation requirement and PaCO2. 7. It is suggested that HMEs are not used as a prevention strategy for ventilator-associated pneumonia.
What are the 9 steps of endotracheal intubation?
1. assemble and check equipment 2. position patient 3. preoxygenate patient 4. insert laryngoscope 5. visualize glottis 6. displace the glottis 7. insert tube 8. assess tube position 9. stabilize tube/confirm placement
Hazards and complications associated with the use of humidification devices
1. Potential for electrical shock (heated humidifiers or HH) 2. Hypothermia—HME or inadequately set HH; hyperthermia— HH 3. Thermal injury to the airway from HH; burns to the patient and tubing meltdown if heated-wire circuits are covered or circuits and humidifiers are incompatible. 4. Underhydration and impaction of mucus secretions ( < 26 mg H2O/L) —HME or HH 5. Hypoventilation and/or alveolar gas trapping due to mucus plugging of airways—HME or HH 6. Possible increased resistive work of breathing due to mucus plugging of airways—HME or HH 7. Possible increased resistive work of breathing through the humidifier—HME or HH—that could result in elevated airway pressures and possible disconnect 8. Possible hypoventilation due to hypercapnia caused by the increase in dead space—HME 9. Inadvertent overfilling or pooled condensate resulting in unintentional tracheal lavage—HH 10. When disconnected from the patient, some ventilators generate a high flow through the patient circuit that may aerosolize contaminated condensate, putting both the patient and clinician at risk for nosocomial infection—HH and HME 11. Potential for burns to caregivers from heating element—active humidifier 12. Patient-ventilator asynchrony and improper ventilator performance due to pooled condensation in the circuit—HH 13. Ineffective low-pressure alarm during disconnection, due to resistance through the HME 14. Compressible volume loss that can lead to inaccurate effective tidal volume (if not calculated) and reduction on ventilator response—HH and HME 15. Dehydration of the airway if temperature is set to body temperature, yet the RH is low—HH
Jet Nebulizer: Components of a Jet Nebulizer
1. Reservoir 2. Jet 3. Capillary tube
Aerosol Therapy Possible Complications: 1. __________ 2. __________ 3. __________ 4. __________ 5. __________ 6. __________ 7. __________
1. Sepsis 2. Swelling of secretions 3. Thermal damage to the airway 4. Retained core body temperature. 5. Fluid overload 6. Bronchospasm 7. Caregiver exposure to droplet nuclei.
Clinical applications in Transcutaneous Monitor include:
1. Titration of ventilation/oxygenation support (decreased need for ABGs). 2. Non-invasive monitoring to determine shock and/or hypoxemia. 3. Monitoring of patients during transports. 4. Exercise testing. 5. Determining perfusion levels in extremities.
What are the objectives of Humidity Therapy?
1. To prevent mucosal irritation. 2. To prevent/correct a humidity deficit.
3 primary types of humidifiers used
1. bubble humidifiers 2. passover humidifiers 3. HMEs
What are the problems caused by an ETT?
1. bypasses upper airway 2. reduces cough effectiveness 3. reduced diameter of passage of airflow 4. can't speak 5. infection/ VAP 6. laryngospasm 7. right mainstem bronchus intubation 8. uncomfortable 9. difficult to stabilize 10. pt can bite tube 11. incorrect placement leads to trauma 12. vocal cord & tracheal damage 13. max time is 7-14 days
CONTRAINDICATIONS for HME
1. for patients with frank bloody or thick, copious secretions. 2. for patients with an expired tidal volume less than 70% of the delivered tidal volume (eg, those with large bronchopleural cutaneous fistulas, tracheal tube cuff malfunction, or presence of uncuffed endotracheal tube) 3. When providing humidification to patients with low tidal volumes, such as when lung-protective ventilation strategies are used, HMEs are not recommended because they contribute additional dead space, which can increase the ventilation requirement and PaCO2. 4. In patients with ARDS, where low tidal volumes are used, and when managing hypercapnia is warranted, HMEs should be avoided 6. for patients with body temperatures 32°C. 7.for patients with high spontaneous minute volumes ( 10 L/min) 8. An HME must be switched to the aerosol bypass mode or removed from the patient circuit during aerosol treatments when the nebulizer is placed in the patient circuit 7.in patients on NIV with large mask leaks, as the patient does not exhale enough tidal volume to replenish heat and moisture to adequately condition the inspired gas.
There are 3 types of HME or artificial nose:
1. hydrophobic 2. hygroscopic 3. a filtered HME
what is a nasopharyngeal airway? (nasal trumpet)
1. made of soft silicone plastic or rubber 2. all are curved to follow the anatomy of the nasopharynx 3. all have a flange at nasal end to prevent accidental aspiration of tube
how to bag-mask ventilate:
1. mask is pressed against nasal bridge with thumb 2. index finger exerts downward pressure on base of mask over chin 3. pinkie engages angle of mandible
what are the disadvantages of a nasopharyngeal airway?
1. nasal irritation 2. sinusitis 3. ottitis media 4. increases airway resistance
What are the 3 ways the mucus layers provide defense?
1. particles are trapped in gel/sol and are transported to the upper airway by ciliary action (mucociliary escalator) where they are expectorated or swallowed. 2. gel/sol fluid can neutralize potentially damaging gases (certain pH can kill viruses ..secondary defense) 3. gel/sol fluid prevent microorganisms from adhering to the epithelium
what are the indications for using an oropharyngeal airway?
1. primarily for unconscious patients 2. relieves obstruction caused by tongue 3. prevents laceration of tongue in seizures 4. used as a bite block with oral ET tubes 5. facilitates suctioning of posterior pharynx
2 physical ways to relieve oral airway obstruction
1. repositioning head 2. displacing the mandible anteriorly
what are the uses of an LMA?
1. routine airway management during general anesthesia 2. emergency airway device 3. may be used as a back up device when ET intubation isn't successful 4. may be used as a last ditch airway where a surgical airway is the only remaining option 5. standard ETT can be inserted through LMA
What are the steps of an open cricothyrotomy?
1. vertical incision over membrane 2. pierce membrane in horizontal plane 3. open and spread to insert 4 or 5 tube 4. secure tube and ventilate
Aerosol Therapy Possible Complications: Retained core body temperature. Prevention/Action: Place a thermometer in-line to monitor temperature. Unless the indication for aerosol therapy is hypothermia, keep the delivered temperature < _____o C. This is a concern only when delivering a heated aerosol to the patient with a fever. In this case, the aerosol could eliminate one of the ways the body gets rid of excess core body temperature (i.e. through the warming and exhaling of cool gases).
?
Inspired gas is then __________ and _____________ as it passes through the exchanger.
?
MDI (Metered Dose Inhalers) Use of the spacer provides for greater deposition of medication in the ___________, with less being deposited in the ____________.
?
What advantages are being used with the wick humidifier?
All of them. Temperature, time, surface area, and contact.
Air entrainment is based on what principle?
Bernoulli
Why is the pass-over humidifier more efficient than the bubble humidifier?
Because the pass-over humidifier can be heated so gas can have the carrying capacity similar to the body.
Why is it generally used in NICU and not at an adult unit?
Because the skin in a premature infant is very thin making the diffusion of gas to the skin very good. Adults already have thick skin and would not work as good.
These conditions are referred to as BTPS conditions (_____ ____________ ____________ ________________).
Body Temperature Pressure Saturated
Passover humidifier
Directs gas over a water surface
What is the purpose of Passover in regards to humidifiers?
Directs gas over the water surface.
How do you troubleshoot bland aerosol therapy bronchospasm?
Discontinue bland aerosol therapy
Aerosol Therapy Aerosol Administration Equipment: ______ bags Placed at a low point in the tubing, between the aerosol generator and the patient, to collect condensation (also called rainout).
Drainage
Describe the general goals for the delivery of oxygen to specific patient populations. ex: emergency room, or critically ill patient with moderate to severe hypoxia
Emergency situation: With suspected hypoxia, give as high FIO2 as possible(nonrebreathing mask). Ideally 100% of high flow or closed reservoir system -Highest possible blood oxygen content -hyberbaric oxygen therapy CO and cyanide poisoning may require -Critically ill patient with moderate to severe hypoxia reservoir or high flow system capable of at least 60% oxygen Changes base on assessment maintain: PaO2 above 60 mmHg and Hb saturation(SaO2 above 90%
Aerosol Therapy Aerosol Administration Equipment: _____ _____ Designed to be strapped under the chin, enclosing the lower part of the face. Many patients find this less confining than an aerosol mask. It is also useful for patients with facial burns.
Face Tents
How do bubble Humidifiers work?
Gas is directed through a tube into the bottom of water and generates bubbles which rises to device outlet to patient
How do Bubble Humidifiers function?
Gas passes down a capillary tube under the surface of the water, then exits through a diffuser at the lower end of the tube.
HME
Heated moisture exchanger
Wick humidifier is usually attached to a _______ ________ _________.
Heated wire tubing
To assure a stable FiO2 under varying patient demands, what must an O2 delivery system do?
If you want it to be stable you must have it deliver all the patients inspired gas. If the device delivers only some of the inspired gas, the patients needs are not met. -FIO2 variable based on patients Vt, VE(minute volume), RR and patients anatomical reservoir (oral and nasal cavity, normally around 50 ml) high volumes higher rates lower FIO2 -more room air is pulled in Lower volumes lower rater higher FIO2 -Less room air is pulled in
____________ solutions will remain stable (neutral toward water absorption) since solute concentrations are similar.
Isotonic
Sizes of OAW
Large (1oomm) Medium (90mm) Small (80mm) Child (40-80)
Sizes of NAW
Large (8-9mm) Medium (7-8mm) Small (6-7mm) Child (12F or ~3mm)
Ultrasonic Nebulizers (USN) is not to be used as a ___________ __________ nebulizer.
Large Volume
What do you use when you have thick secretions when the patient is on an HME ?
Large volume jet nebulizer
What is the most common device to deliver bland aerosol?
Large volume nebulizer
Aerosol Devices:
Large-Volume Jet Nebulizer Ultrasonic Nebulizer
What is the most common device used for bland aerosol delivery?
Large-Volume Jet Nebulizers
What are all airway appliances used with and why?
Large-bore tubing to minimize flow resistance and to prevent occlusion by the condensation.
What is considered the lowest clinical SpO2 in a pulse oximeter?
Less than 92% SpO2
Define and contrast low flow and high flow devices (including minimum and maximum flows) high flow
Low Flow: Nasal cannula, .5 to 6 L/min, FiO2: 24-44%, stability: variable use humidifier over 4L Nasal catheter, 1/4 to 8L/min, FiO2: 22-45%, stability: variable Transtracheal, 1/4 - 4L/min, FiO2: 22-35%, stability: variable Reservoir, 1/4 - 4L/min, FiO2: 22-35%, stability: variable Simple Mask, 6-12L/min, FiO2: 35-55%, stability: variable Partial rebreathing, 6-15+L/min, FiO2: 60-80% stability: variable Nonrebreathing, 6-15+L/min, FiO2: 80-95%, stability: variable AEM/venturi, 3-15L/min, FiO2: 24-55%, stability: fixed below 35% aerosol mask with air entrainment nebulizer: 6-15L/min, FiO2: 28-100%, stability: fixed High flow nasal cannula: 35-90%, fixed or variable Oxygen Hoods: 22-100% 6-15+L/min Oxygen Tents: 22-50% 8-15+L/min
Can you disable the safety alarm in the Air Oxygen Blender?
No, if you do, then you will be jeopardizing your license.
What mask is the bubble humidifier designed for? (if using less than or equal to 7 LPM).
Nasal cannula
Low flow devices
Nasal cannula Simple face mask Partial rebreathing mask Nonrebreathing mask Tracheostomy collars
What is the reservoir for nasal cannulas?
Nasopharnynx+ Oropharynx+ nasal cavity 1/3 atomical deadspace = nasal cannula reservoir
Do you want to cure patients? (Purpose of HME?)
No, Because you want to make the patients strong enough to promote the healing process. (You want to make patients well enough to cure themselves).
Correcting Hypoxemia
O2 therapy corrects hypoxemia by raising oxygen levels of: alveoli and blood -Hypoxemia and lung disease Relieves hypoxic symptoms associated with certain lung disorders. COPD Interstitial lung disease: Relief of dyspnea. Improve mental function of the chronically hypoxemic
Air Oxygen Blender used with NICU applications must be in conjunction with an ________ _______.
Oxygen Analyzers
Device that is used to determine the FIO2 of a delivered gas.
Oxygen Analyzers
What is used to deliver a precise FIO2?
Oxygen Blenders
What is used to verify the oxygen sample of gas?
Oxygen analyzer
Which type of Humidifier is the simplest of all humidifiers?
Pass-Over Humidifier
The _________________ humidifier are very inefficient with high gas flowrates.
Pass-over
What humidifier is the least efficient design in picking up humidity?
Pass-over Humidifier
What is the simplest of all humidifiers?
Pass-over Humidifiers
Function of an OAW?
Relieves obstructions Protects ETT from being bitten Facilitates airway suctioning
What decreases the humidity output?
The CONTACT TIME!
What functions as the normal airway humidifier?
The nose
How does the pass-over humidifier become most efficient in delivering gas to the patient? Why?
The pass-over humidifiers become the most efficient humidifier when a heated wire is added to the tubing. Because the heated wire maintains the temperature of the gas that also maintains the carrying capacity of the gas.
The major problem with air entrainment systems is ensuring that the set FIO2 is actually delivered to the patient. Explain causes and solutions to this problem
This can be caused if there is entrainment in the tubing. To fix this you would need to drain all the excess water form the tubing. You can also watch the mist come out the expiratory side of the T tube. If there is mist, they are getting enough FIO2
You are asked to suggest a lung inflation therapy for a 55 year old man who is 72 inches tall and weighs 85 kg. He has just undergone a cholecystectomy, and his chest radiograph shows right middle lobe atelectasis. He has a 10 pack per year history of smoking cigarettes, and his preoperative pulmonary function studies showed that his vital capacity was 20 ml/kg. He is alert and cooperative but complains of some upper abdominal pain when taking a deep breath. What modality would you suggest?
This patient is a good candidate for incentive spirometry; he is alert and cooperative. Although he does experience some pain when he takes deep breaths, he should be able to take deep breaths (vital capacity>10 ml/kg)
What happens to particles when delivering cool aerosols
Travels down the respiratory tracts, evaporates and become smaller
What do you use to humidify an oxihood ?
Use wick/passover humidifier
"Wick" Technology
Uses a porous water-absorbent material to increase surface area
Hygroscopic Condenser
Uses a thermal element of low thermal conductivity (paper, wool, foam)
How to avoid cross contamination in humidifiers
a. Condensation should be discarded in a trash contain and never returned into the humidifier. b. The humidifier should be changed every 24 hours.
Which of the following is a contraindication to use of an HME? a) minute volume greater than 10L/min b) minimal secretions c) small tidal volumes d) short-term mechanical ventilation
a) minute volume greater than 10 L/min
Techniques used to reduce volume of condensate within circuit
a. Adding water traps to low point in the circuit to allow collection and removal of condensate b. Maintain temperature within the circuit - Insulate the circuit - Heating elements/wires within the circuit
Best use for jet nebulizers
a. Patient with tracheal airways requiring long-term supplemental humidification. b. Short term application to patients with upper airway edema & to thin out secretions c. Single treatment application for sputum induction--- may use hypertonic saline
Jet Nebulizers
a. Produce aerosols via shearing water into particles at a high - velocity gas jet b. Typically incorporate baffles to remove large particles from the suspension. c. The low pressure at the gas jet can be used to entrain air, providing for increased flow & variable FIO2 d. Heating the water reservoir will increase total water output
Equipment for Aerosol drug-delivery Therapy
a. Small Volume Jet Nebulizers (SVNs) b. MDI c. MDI with valve holding chamber or spacer d. DPI e. Ultrasonic Nebulizers (USNs) f. vibrating mesh nebulizer
Complications of condensation in humidifiers
a. Wastes large amounts of water b. Can disrupt or occlude gas flow through the delivery circuit possibly altering FIO2 or ventilator function c. Can be aspirated by the patient d. Quickly colonized with bacteria and poses an infection risk to patient and healthcare provider.
How to ensure proper humidity is being delivered to the patient
a. small amount of condensate (commonly referred to as vapor trail) should be seen in the artificial airway b. Water levels of all humidifiers should be maintained as marked to ensure maximum humidity output. c. Inspired gas temperature should be monitored continuously with an inline thermometer when using heated humidifiers d. The thermometer should be as close to the patient wye as possible.
actual amount or content of water vapor within a given volume of gas
absolute humidity
wick is a cylinder of
absorbant material placed upright in the water heated reservoir
Disadvantages of MDIs MDIs are much more prone to _____ than SVNs.
abuse
Pulse oximeters are perfusion-dependent, that is, they will not read ___________ when perfusion is decreased (like when the hands are very cold).
accurately
What else are humidifiers classified as?
active-heat and/or water is added passive-recycled heat and/or water from patient
Absolute Humidity
actual amount or content of water vapor with in a given volume of gas
Heat & Moisture Exchangers
are often referred to as artificial noses
When ISB shifts occurs additional surfaces of the airway
are recruited to meet the heat and humidity requirements of the lung.
Disposable CO2 Detectors is a main use to verify placement of an ____
artificial airway
HME's are often referred to as
artificial noses
How does temp affect evaporation and resulting absolute humidity?
as temp increase the rate of evaporation increases
What are some of the complications of a combitube?
aspiration (ensure there's no gag reflex) esophageal perforation direct trauma to the larynx
on the power unit of USN there is a
blower
the capacity at 37 degrees Celsius is 44 mg/L of gas
body humidity
BTPS
body temp @ atmosphere pressure saturated
The trachea contains?
both ciliated and non ciliated epithelial cells
relative contraindication
bronchospasm
what are the types of low flow humidifiers?
bubble diffuser
types of humidifiers
bubble , passover, HME, heated
three methods to create surface area
bubble diffusion, aerosol, "wick" technology
The vest is used to: a) provide positive pressure on exhalation b) keep infants' core temperature stable c) oscillate the chest wall to promote secretion clearance d) provide a biofeedback in the teaching of diaphragmatic breathing
c) oscillate the chest wall to promote secretion clearance
You can adjust the tidal volume delivered by a Bird Mark 7 ventilator by manipulating which of the following parameters? a) inspiratory time b) inspiratory flow c) peak inspiratory pressure d) trigger sensitivity
c) peak inspiratory pressure
How do you troubleshoot bland aerosol therapy overhydration?
careful patient selection and monitoring
What are the sinuses?
cavities formed by cranial bones provide humidification & warming of inspired air, lightening of skull, secretion of mucus to assist filtration
pneumatic nebulizer
contains a baffle to stabilize the particles
in the nebulizing unit of USN it...
contains a piezoelectric transducer
What is a double cannula tracheostomy tube?
contains inner cannula inner cannula can be removed and cleaned inner cannula can be disposable or permanent
How do you calculate body humidity?
content(aka AH)/44 x 100 = %BH
How do you determine relative humidity?
content/capacity x 100% =
What are the treatments post extubation?
cool mist aerosol for mild or moderate stridor administer .5ml of 2.25% racemic epi via mini neb administer steroids
MDI (Metered Dose Inhalers) Less _____ is required to effectively use the MDI when it is combined with a spacer.
coordination
What are the reflex responses?
coughing sneezing bronchoconstriction increased mucus production
in a nebulizing unit, the piezoelectric disk sits in this bath called the _______
coupland
bubble diffusion
create small bubbles to increase surface area
What are the signs of upper airway obstruction?
crowing, gasping on inspiration inability to cough/talk poor air exchange cyanosis
What should you perform to determine risk of post-extubation stridor?
cuff leak test
What is a 3 way stopcock w/ manometer?
cuff monitoring device reads in cmH2O can use BP cuff reading in mmHg
What is a colorimetric CO2 analyzer?
disposable device similar to capnometer but instead of actual readout of CO2 it changes color when CO2 is encountered
absolute contraindications
do not give no matter what, NEVER
MDI (Metered Dose Inhalers) The canister is activated by pressing ______.
down
Disadvantages of MDIs Some patients do not respond well to the ___ medications in MDIs.
dry
how do you measure a nasopharyngeal airway?
from tip of nose to bottom of ear
What are the 2 layers of the mucus?
gel sol
fluid overload is a problem with
infants
What can high cuff pressure cause?
inflammation and hemorrhage in 24 hours mucosal necrosis in 48hrs necrotic cartilage in 5 days
MDI (Metered Dose Inhalers) Correct use requires patient ________________ and _____________.
instruction; coordination
USn should not be given contiously only
intermentially
Insertion of an ETT is known as?
intubation
What is a Macintosh laryngoscope?
intubation equipment has a curved tip displaces the epiglottis indirectly by advancing the blade into the vallecular notch and lifting up and forward
a way to prevent "rain-out"
is to use a heated wire circuit in the tubing to keep the temp throughout the tubing constant; water traps
ISB
isothermic saturation boundary: above this temp and humidity decrease during inspiration and increase during exhalation
swelling of dry, retained secretions are most common with a ultrasonic neb bc?
it delivers a high vol of moisture
as the dry gas enters the system ,
it flows around the wick picking up moisture
as the dry gas enters the system,
it flows around the wick picking up moisture
How to identifiy a jet intermittent
it has a reservior with a baffle
mucosal humidity
it hydrates dried, retained secretions, promotes expectoration and improves cough effectiveness
How does the surface area affect evaporation and resulting absolute humidity?
it is a direct relationship. bigger the surface area there is more evaporation
Because the system is heated, as the gas travels from the humidifier to the patient,
it will cool causing rain out. it requires the tubing to be drained frequently
If the tube is in the esophagus what will happen to the CO2?
it won't change
if jet portion falls out in an SVN
it won't work
How does pressure affect evaporation and resulting absolute humidity?
its a indirect relationship. as pressure increases the evaporation decreases
The viscosity of mucus is dependent on?
its concentration and molecular characteristics of the mucous glycoproteins (mucins) (WBCs, proteins, etc.)
What do you do to manually ventilate?
make sure airway is patent determine whether pt has spontaneous breaths evaluate depth and rate of spontaneous breaths manually ventilate with BVM if necessary
baffle
makes particle size smaller and more uniform
What are the 3 difficult intubations?
mallampati test neck size rapid desaturation
secondary indications for humidity therapy
managing hypothermia, treating bronchospasm caused by cold air
what is the LMA currently frequently used for?
many general anesthesia cases on a routine basis
What happens when the esophageal obturator is removed?
may cause vomiting
how do you select the appropriate size for an oropharyngeal airway?
measure from edge of mouth to bottom of ear
absolute contraindication
no USn for infants
The primary goal of humidification is to maintain
normal BTPS conditions
What are the symptoms of tracheal stenosis?
not evident until after extubation and often doesn't develop until months later patients present dyspnea on exertion, cough, and secretion production
vapor humidity
not visible and its not:(s.a.m. v) -steam -aerosol -mist -vapor trail
MDI (Metered Dose Inhalers) Activation results in the release of a _____________ dose of medication into the mouthpiece.
null
What are the indications for surgical airways?
obstruction facial trauma intubation or alternatives impossible trismus (lockjaw) older than 8yrs old LAST RESORT
how can an OAW that's too long cause complications?
obstructs larynx by forcing down epiglottis
How do you check that the tube is in proper position?
obtain CXR and visualize its position in extreme cases, a bronchoscope can be inserted directly into the tube to visualize the carina and tip of tube
what are the contraindications of an esophagel obturator?
patient is alert, responsive, or has gag reflex less that 16yrs old ingested caustic substance very short <5ft or very tall >7ft
What are the relative contraindications for a double lumen ETT?
patients requiring rapid intubation to prevent aspiration of gastric contents patients who are likely to be difficult to intubate
SPAG mode of operation
pneumatic
_______ nebulizers contain baffles to stabilize the particles
pneumatic
jet intermittent mode of operation
pneumatic
mode of operation for a jet reservoir
pneumatic
mode of operations with a SPAG
pneumatic
What does the dendrite/antenna cell do?
pokes surface to feel around to detect what's occurring
What does breathing expose the lungs to?
pollutants viruses bacteria if they get into the lower airway it causes infection
"wick" technology uses
porous water-absorbant material to increase surface area
What are the immediate complications for extubation?
post extubation glottic and subglottic edema laryngospasm auscultate upper airway for inspiratory stridor
signal frequency
preset by the manufacturer and determines aerosol particle size
there is an indirect relationship with the rate of evaporation because an increased ______ causes a decreased evaporation
pressure
vapor pressure
pressure excerted by water vapor in a given volume of gas
What is the optimal way to monitor cuff pressure?
pressure manometer: objective, easy to use add or remove air reads in cmH20
the bubble humidifiers incorporate a
pressure relief valve, release pressure above 2 psi, used to test for system leaks
Incorporate a pressure relief valve (pop-off)
release pressure above 2 psi and also used to test the system for leaks
What is a nasal endotracheal tube?
same type as ETT can be inserted orally or nasally may be used if oral intubation is impossible apply lidocaine to nose and insert slowly on inspiration Magill forceps can be used to guide tube into trachea
What are the basics of the Mallampati test?
score 1 is good score 4 is trouble expect difficult intubation and prepare for it
What is a Mallampati test?
scored based on what can be visualized in the mouth
What are immune cells?
secrete Immunoglobin A (IgA) antibody
Aerosol Therapy Objectives: To thin/liquefy _____.
secretions
What is the cuff leak test?
see of airways are swollen testing whether or not the patient can breathe on their own by seeing how much air comes back through the tube rather than out the mouth
factors affecting evaporation and resulting absolute humidity
temp, pressure, surface area, time
What are the temp and humidities for the hypopharynx?
temp: 29-32 RH: 95% AH: 28-34mg/L
What are the temp and humidities for the trachea?
temp: 32-35 RH:100% AH: 36-40mg/L
as _______ increases, the rate of evaporation increases
temperature
the most important factor affecting humidifiers
temperature
physical factors affecting humidifiers
temperature, surface area, contact time
humidity deficit
the actual moisture deficit between the inspired air and the needs of the body
body humidity
the amount of water vapor in a gas sample as compared to the capacity of water vapor at body temperature
identification of a jet reservoir
the baffle makes particle size smaller and more uniform
Use a jet intermittent for
to deliver aersolized med's
Why should cuff pressure be kept between 20-25mmHg?
to prevent reduction of blood flow through the capillaries
What are some causes of upper airway obstruction?
tongue blood/secretions laryngospasm/Edema Foreign substances (teeth, vomit)
Capacity
total amount of water that can be held by a gas at a specific temp
The condensation in a circuit poses a risk
tp Pts and caregivers and can waste a lot of water. (ie: bacteria building)
Inspired dry gas through an artificial airway can lead to?
tracheal epithelium damage very quickly!
what is convection?
transfer of heat from the body to air
the piezoelectric transducer
transforms the ultra high freq. electric current into ultra high freq. vibrations
What does PANGOS stand for?
types of pts for rapid desat Pregnancy Ascites (liquid) Neonate General Anesthesia Obesity Supine
What causes obstructive sleep apnea?
while laying down the tongue falls back
types of Passover Humidifiers
wick and membrane
Which humidifier can deliver gas at 100% body humidity?
wick humidifier
What can help minimize condensation to reduce the risk of colonization?
wick or membrane type Passover humidifiers prevent formation of bacteria-carrying aerosols. No need to frequently change the circuit.
passover humidifiers types:
wick, membrance
If the tube is in the trachea what will happen to the CO2?
will rise during expiration