Unit 1 2255 Exam
ventilation-perfusion mismatch
this occurs when the ideal proportion of ventilation in a lung area is either greater or lesser than the amount of blood flow
Following are data for a patient receiving ventilatory support after abdominal surgery:Mode: VC-CMVSet rate: 12/minuteV T: 450 mLPEEP: 5 cm H 2OF IO2: 0.35Total rate: 12/minuteS PO2 : 93%Which of the following best describes the trigger variable?
time
Pressure support may be added to pressure control-synchronized mandatory ventilation (PC-SIMV).
true
Pressure support may be added to volume control-synchronized intermittent mandatory ventilation (VC-SIMV).
true
What are the primary functions of the upper ariway?
upper airway are to filter, warm, and moisten inspired air
Steps for Extubation
Position patient upright in Fowler's position with head of bed raised 45 and knees elevated slightly? . Suction secretions from ET tube and oropharynx? . Deflate the cuff? . Remove the tube on exhalation in one steady, smooth motion
What is the most common baseline variable?
Pressure
What are the possible control variables?
Pressure Flow Volume Time
What may be used as trigger variables?
Pressure Flow Volume Time
What is Poiseuille's Law?
- If diameter (2r) is reduced by one-half, resistance increases 16 times (r4).
Describe the steps when intubating a patient.
1. Manually ventilate the patientand pre-oxygenate using 100% O22. With the patient in sniffingposition, hold the laryngoscopein the left hand and graduallyinsert the blade into the right sideof the patient? fs mouth so that thetongue can be shifted left3. Lift up and away to visualize thevocal cords4. Insert the ET tube with the styletin place into the mouth andvisualize it passing through thevocal cords5. Remove the blade and inflate thecuff with a 10 cc syringe6. Secure the tube7. Record the centimeter mark8. Auscultate for bilateral breathsounds
Given a volume change of 500 mL with a pleural pressure change of 5 cm H 2O, what is the pulmonary compliance?
100 mLcwp
Airway resistance is an important concept in mechanical ventilation, because when the airway radius is reduced by 50% airflow resistance increases by:
16 times.
What percentage of the thoracic volume change is achieved through diaphragmatic action when tidal breathing in the upright position?
50%
What best describes a cycle variable?
A variable that determines the end of inspiration variable that determines the end of inspiration
What best describes trigger variable?
A variable that initiates the start of inspiration
What best describes a limit variable?
A variable that rises to a preset value and remains constant during inspiration
Given a volume change of 500 mL with a pleural pressure change of 5 cm H 2O, what is the pulmonary compliance?
A. 100 mL/cm H2O
Extubation Criteria
Acceptable respiratory pattern without a great deal of pain? . Cardiovascular stability and proper circulation? . Superficially warm and wellperfused? . Awake and cooperative with adequate neurological function? . Stable vital signs and acceptable ABG values on FIO2 of 0.50? . SpO2 > 94% unless the patient has COPD
When establishing volume control-continuous mechanical ventilation (VC-CMV), what control determines the length of inspiration?
A. Flow rate
Another term for assist-control ventilation is:
A. continuous mandatory ventilation.
What are factors that affect airway resistance?
Airflow obstruction • Secretions • Edema • Bronchospasm • Tumors outside the airway
Which of the following forms of high-frequency mechanical ventilation requires a sliding venturi?
C. High-frequency percussive ventilation (HFPV)
Which are the most commonly used approaches to mechanical ventilation?
C. Invasive positive pressure ventilation and Noninvasive positive pressure ventilation
The medical team wants to maintain a constant tidal volume in the patient with acute head injury. Which type of mechanical ventilation should be used?
C. Volume control ventilation
The application of positive airway pressure during spontaneous ventilation both during inspiration and exhalation best describes:
C. bilevel positive airway pressure (BiPAP).
Spontaneous ventilation without any ventilator assistance is best described as:
C. continuous spontaneous ventilation (CSV).
During mechanical ventilation, the flow is paused momentarily at end inspiration. This maneuver is done to:
C. evaluate a patient's lung compliance.
A ventilator mode is best defined as a:
C. predetermined pattern of ventilation between the patient and the ventilator.
A ventilator mode that delivers a preset pressure and is time triggered best describes:
C. pressure control-continuous mechanical ventilation (PC-CMV).
A mode of BiPAP that provides a backup rate in the absence of spontaneous breathing is:
C. spontaneous-timed.
The ventilator breath ending once time reaches a preset value best describes:
C. time cycling.
Define Abnormal Lung Compliance when it is Low or High. Also, some causes.
Abnormal lung compliance- Low lung compliance• Lungs are stiff or noncompliant.• Causes: Atelectasis, acute respiratory distress syndrome (ARDS).- High lung compliance• Lungs are easily opened and inflated at a given inspiratory pressure.• Cause: Emphysema
A ventilator mode that delivers a preset volume and is time triggered best describes:
C. volume control-continuous mechanical ventilation (VC-CMV).
Name four different types of noninvasive airway management.
CPAP HFNC BVM LMA
What tubes are used for blind insertions and for which patients?
Combitube:Multi-lumen airway that works inserted into the esophagus or tracheaFor patients > 5 ft, > 14 years of age, without a gag reflex, esophageal trauma or diseaseKing TubeOnly works inserted into the esophagusAvailable in 3 sizes for patient> 4ft.
When should nasal intubation be used on a patient? How can you determine you are in the correct position and when is nasal intubation contraindicated?
Patient can be awake and breathingBypasses the gag reflexLook for flashes of humidity within the ET tube as in indicator ofcorrect positioning? . Contraindicated in patients with bloodclotting abnormalities,on anticoagulants? . Usually short-term due to risk of sinusinfections
Which of the following forms of high-frequency mechanical ventilation requires a special airway or airway adapter?
B. High-frequency jet ventilation (HFJV)
A patient is being ventilated with pressure control continuous mandatory ventilation (PC-CMV). The patient's lung compliance has decreased and airway resistance has remained stable. What effect will these changes in pulmonary mechanics have on tidal volume (V T) delivery?
B. VT will decrease.
A patient is receiving volume control continuous mandatory ventilation (VC-CMV). The patient's peak inspiratory pressure has become progressively higher over the last hour. What effect will this have on the tidal volume (V T) delivered to the patient?
B. VT will remain constant.
Which ventilator setting delivers a constant tidal volume?
B. Volume control ventilation
Volume can become a limit variable if:
B. an inspiratory pause is used.
A ventilator initiating inspiration based upon a preset change in flow is referred to as being:
B. flow triggered.
Increased baseline pressure during mandatory (ventilator-assisted) breaths is termed:
B. positive end-expiratory pressure (PEEP).
The volume change that occurs as a result of thoracic expansion is an application of:
Boyle's law
The volume change that occurs as a result of thoracic expansion is an application of:
Boyles Law
During MV a rising PP would indicate _____ compliance.During PCV a rising Volume indicates _____ compliance.Measurement of compliance- Dynamic compliance: Measured during _______- Static compliance: Measured when ________
Compliance equation is a very useful tool in mechanical ventilation.- During volume-controlled ventilation, rising plateau pressure indicates decreasing compliance (and vice versa).- During pressure-controlled ventilation, increasing volume indicates increasing compliance (and vice versa).• Measurement of compliance- Dynamic compliance: Measured during conditions of airflow.- Static compliance: Measured when there is now flow.
How is compliance measured?
Compliance is a measure of the dispensability of the lungs:- CL is the compliance of the lungs/thorax.- is the change in volume.- is the change in pressure.
Which of the following best describes a trigger variable?
D. A variable that initiates the start of inspiration
Which of the following best describes a limit variable?
D. A variable that rises to a preset value and remains constant during inspiration
Which of the following are spontaneous modes?
D. Continuous positive airway pressure (CPAP)
During volume-controlled ventilation, a patient's peak inspiratory pressure has been increasing over the past 8 hours. What is the cause of this change?
D. Increasing airflow resistance or decreasing compliance
A decrease of the peak inspiratory pressure-plateau pressure (PIP-P plat) gradient implies that the
D. airflow resistance has decreased.
The control variable is best described as a variable that:
D. is measured and used to control the ventilator's output.
A form of assisted or augmented spontaneous breath where pressure is applied during inspiration best describes:
D. pressure support (PS).
The ability of the patient to breathe spontaneously between ventilator (mandatory) breaths best describes:
D. synchronized intermittent mandatory ventilation (SIMV).
Immediate complications of a trachea tube are
Damage to tracheaAir trapped in tissue under skin of neck (subcutaneous emphysema), which can cause breathing problems and damage to the trachea or esophagusPneumothoraxHematomaMisplacement or displacement of the tracheostomy tubeBleeding
A mechanically ventilated patient has shown significant clinical improvement. The lung consolidation and bronchospasm are almost completely resolved. Which of the following demonstrates the patient's improvement?
Decrease in Pplat, large decrease in PIP
What ventilator targeting scheme allows the ventilator to change from pressure to volume or from volume to pressure targeting?
Dual
What are factors that increase Raw?Why is Raw higher if the patient is intubated?
Factors increasing airway resistance:- COPD- Foreign body obstruction- Artificial airway (e.g., too small, too long, right mainstem intubation)• Airway resistance is higher in intubated patients.- Smaller airway diameter- Internal diameter influences resistance the most.• Larger tubes are better.
A ventilator initiating inspiration based upon a preset change in flow is referred to as being
Flow triggered
Name the items that should be in an airway box.
Gloves10 mL syringeBVMDisposable CO2 detectorLaryngoscope handle andblades (Mac and Miller)Extra batteriesWater-based lubricantGauze tapeEndotracheal tubes (sizes5.0 to 9.0 mm) with styletNasopharyngeal airways ofdifferent sizesOropharyngeal airways ofdifferent sizesEndotracheal tubeholder/securing method
The Mallampati score is a simple test that can be a good predictor of obstructive sleep apnea. the images are class 1 through class 4
Grade ITongue is smaller andnot extremely wide? . Soft palate is visibleGrade II? . Tongue is broadenedand takes up morespace in the oral cavity? . View of the airway ispartially obscuredGrade IIIGlottis and uvula cannotbe visualized? . View of the oral cavity isobstructedGrade IVGlottis or corniculatecartilages cannot beviewed? . Tongue is excessivelywide and obtrusive
What type of tubes are available?
HIGH- VOLUMELOWPRESSURECUFFLOW-VOLUMEHIGHPRESSURECUFFHI-LO EVAC
What causes hypoventilation (Vent Failure) and the clinical presentation?
Hypoventilation- Causes• Spinal cord injury• Neuromuscular disorders• Overdose of analgesics or sedatives• Severe airway obstruction• Central sleep apnea- Clinical presentation• Reduced minute ventilation• Hypercapnea
Which of the following may be used as trigger variables?
I. PressureII. FlowIII. VolumeV. Time
Intubation done too late will often lead too___.
INtubation done too late often leads to prolonged hypercapnia, hypoxemia, and duration of mechanical ventilation.
When establishing pressure control-continuous mechanical ventilation (PC-CMV), what control determines the length of inspiration?
Inspiratory time
The control variable is best described as a variable that:
Is measured and used to control ventilator's output
Signs of Extubation Failure
Laryngeal spasm? . Desaturation (SpO2 < 94%)? . Need for reintubation 24 to 72 hours after planned extubation? . Decreased peak expiratory flow rates (< 60 L/min)
Describe mac vs. miller.
MAC VERSUS MILLERMac bladeinserts intothevalleculaMiller bladetip capturestheepiglottis
Prior, and during the intubation procedure how do you maintain airway clearance with suctioning? What is the procedure?
Maintaining proper suctioning to clear the airway as indicated bypatient signs rather than a fixed schedule ProcedurePre-oxygenate to minimize riskof iatrogenic hypoxic eventsGently advance the suctioncatheter to the proper depthApply suction while pulling thecatheter back ? . Normal saline instillation. Avoidunless unable to remove detectedsecretions. Use only 3 to 5 mL anddeliver a few breaths to loosensecretions before suctioning.? . Suction depth . Forcefully advancingthe catheter too far into the trachea cancause the catheter to coil at thebifurcation, airway trauma, andbleeding
Describe the steps from measuring to considering using NPA.
Measure from nare to tragus (bottom of the ear canal)Lubricate prior to insertionInsert with bevel tip toward nasal septum and the naturalcurvature of the nasal passageSlide gently to rest in posterior pharynxPull back a few centimeters if resistance is metTwist slightly and re-advanceConsider the opposite nasal passage if still resistant
Which trigger variables is based on the electrical activity of the diaphragm?
Nava
How does an oropharyngeal devices assist during intubation, describe the steps? Also, how do you measure, insert, or why would you rotate the device?
OROPHARYNGEALHolds the airway and tongue intoposition from the posteriorpharynxDoes not isolate the tracheaSizes range from 0 (smallest) to 5(largest)ICATIONS NEEDEDMeasure from corner of the mouth tothe angle of the jawInsert with the curve towards theside of the mouthRotate so that the curve of theairway matches curve of the tongue
Adaptive support ventilation (ASV) uses what targeting scheme?
Optimal
Normal exhalation:
Passive
What if the tube is place in the RMS or in the Esophagus, what signs would the patient exhibit? How would you correct your patient?
RIGHT MAIN STEMexhaled carbon dioxide detectors and colorimeters can aid in determining proper intubation;post-intubation chest x-ray confirms proper placementCorrecting right main stembronchus intubation? . Deflate the cuff slightly.? . Pull back the tube gentlyapproximately 1 to 2 cm.? . Re-inflate the cuff.? . Re-secure the ET tube.ESOPHAGEAL INTUBATIONVERIFICATION FOR VENTILATION SUCCESSSigns of esophageal intubation? . Development of progressive hypoxemia andhypoxia despite receiving 100% O2 and BVMventilation? . Epigastric sounds during inspiration? . No bilateral chest expansion? . Abdominal distention? . Excessive difficulty ventilating the patient
Which of the following are ventilator targeting schemes?
Set-point
Name the Benefits of NIV.
Shortens the time needed for artificial ventilatory support
How do you verify ventilation success? What are signs of effective artificial ventilation?
Signs of effective artificial ventilation? . ? ª SpO2? . Improving skin color? . ? ª level of consciousness? . Adequate chest rise? . Quiet ventilation.? . Improving bloodgases? . Normalization ofheart rate? . Good bilateralbreath sounds
What is (are) a source of input power?
Which of the following is (are) a source of input power? Electricity Pneumatics
Dynamic Compliance
The change in volume in for a given unit of applied pressure when gas is moving in the respiratory system.
The term drive mechanism best describes:
The source of power for the ventilator
36 The term control circuit best describes
The source of power used to control the ventilator
The ventilator breath ending once time reaches a preset value best describes:
Time cycling
What are examples of V/Q mismatching, when does it increase, and their examples?
V/Q mismatching- Increases in dead space ventilation• Pulmonary emboli• Increases V/Q ratio- Intrapulmonary shunting• Pulmonary perfusion without ventilation• Low V/Q ratio
An adult ventilator patient has an observed respiratory rate of 20 breaths per minute; the ventilator rate is set at 12 and the V T of each breath varies, ranging 350 to 500 mL per breath. The most likely mode of ventilation is:
VC-IMV
What are the medications needed for rapid sequence intubation (RSI) agents typically used during intubation?
VECURONIUM BROMIDENURCURON15 to 30 min< 1 minIV push 0.04 to 0.06 mg/kgduration.onset.dose.ETOMIDATEAMIDATE, HYPNOMIDATE3 to 12 min< 45 secIV push 0.3 to 0.6 mg/kg IVPGive over 30 to 60 secDoes not affect cardiacmetabolismNo depression of cardiacoutput or pulmonarycirculationMay cause some drop inblood pressureduration.onset.dose.note.KETAMINEKETALAR10 to 20 min< 45 to 60 secIV push 1.0 to 2.0 mg/kgor 0.25 to 0.5 mg/kg IVPAnalgesic and anestheticsedativeGreat way toaccommodate sympatheticsurgeWill have a first passresponse with IV pushduration.onset.dose.note.PROPOFOLDIPRIVAN10 minimmediateIV push 1.5 to 3.0 mg/kgif hemodynamicallyunstable (shock) use nomore than 15 mgOnset may be longer dueto decreased cardiacoutput when in shockGive with ketamine duringRSIduration.onset.dose.note.SUCCINYLCHOLINEQUELICINE, ANECTINE3 to 5 min< 30 sec2.0 mg/kgNeuromuscular blockerAdminister higher dosewhen in shockOnset may be longer dueto decreased cardiacoutput when in shockduration.onset.dose.note.? . Transfuse hypotensiveor septic shock patientswith fluids prior tointubation to avoidfurther drops in bloodpressure? . Medications that are notrecommended includemidazolam (Versed) andfentanyl (Sublimaze)
One of the conditions leading to vent failure is venous admixture. How does this happen? Do RTs have to take extreme measures to fix this or what type of therapy needs to be used?
Venous admixture• Mixing of oxygenated blood and deoxygenated blood after passing through the lungs• Responds well to traditional oxygen therapy
Ventilatory failure happens when CO2 production exceeds CO2 removal. Describe the two factors that this results in and the causes of vent failure.
Ventilatory failure- CO 2 production exceeds CO 2 removal• CO 2 retention• Acidosis- Causes of ventilatory failure• Hypoventilation• V?/Q? mismatch• Intrapulmonary shunting• Diffusion defects
How do you determine on a ventilator P-V loop that their is an increase in Raw?
Waveform displays- Pressure-volume (P-V) loop- Widening of the loop reflects an increase in airway resistance
What does the pressure gradient (ΔP) represent in the compliance (C = ΔV/ΔP) and airway resistance (R = ΔP/V) equations?
Work of breathing
intrapulmonary shunting
a condition in which blood flowing through a lung area is exposed to under-ventilated or unventilated alveoli, resulting in significant hypoxemia
hypoxia
a lack of sufficient O2 in the tissues or organs
hypoxemia
a lower than normal level of o2 in the blood
Plateau pressure
a stable pressure measured at the end of an inspiratory hold
For mechanically ventilated patients, pressure support ventilation (PSV) is useful to compensate for the increased work of breathing due to:
airflow resistance.
Volume can become a limit variable if:
an inspiratory pause is used
Proportional assist ventilation (PAV) uses what targeting scheme?
servo
Oxygenation failure
severe hypoxemia due to any condition
Static Compliance
the change in volume in the respiratory system for a given unit of applied pressure at the end of inspiration but before exhalation
peak inspiratory pressure
the largest pressure attained during inspiration
airflow resistance
the opposition to flow caused by frictional forces and expressed as the ratio of driving pressure to the rate of gas flow
pressure-volume slope
the rate of change observed in a pressure-volume plot of a breath
During spontaneous ventilation, elevated baseline pressure is termed:
cpap
The ventilator variable that is responsible for ending inspiration is the:
cycle variable
The equation corrected tidal volume/(peak inspiratory pressure - PEEP) is used to calculate the patient's:
dynamic compliance.
How do you know when you are successful in intubation?
exhaled carbon dioxide detectors and colorimeters can aid in determining proper intubation;post-intubation chest x-ray confirms proper placement
All of the following are control variables on the modern ventilator that a clinician manipulates to assist breathing, except:
flow control
Following thoracic surgery, as a patient receiving mechanical ventilatory support begins to wake up from anesthesia, the patient coughs and bites down on the endotracheal tube. Which alarm will be activated?
high airway pressure
Define a difficult airway. Therefore, what body habitus, head or neck injuries that could cause a diffiuclt airway?
include emesis, non-standard patient positions, body habitus, and head or neck injuriesBody HabuitusDoes the patient have a large neck?Is the patient obese?Are there obvious anatomical variations which would make establishing an airway difficult?Head or Neck InjuriesHas the patient suffered a traumatic event, MVA, or bodily injury involving the neck?Has the patient fallen and hit their head and lost normal color, become diaphoretic, or unresponsive?
A rapid shallow breathing pattern leads to V̇/Q̇ mismatch due to a(n):
increase in dead space ventilation.
dead space ventilation
is the volume of a breath that does not participate in gas exchange. It is ventilation without perfusion.
If during inspiration the pressure increases to a preset value and doesn't change until exhalation, the pressure is termed a:
limit variable
When assessing an arterial blood gas, if the change in the pH corresponds to the change in the HCO 3 -/BE, it is a __________ disorder.
metabolic
In regards to the colorimeter if the color remains purple, there is ____ confirmation of _____ production. If it changes to ____ it is a ______ confirmation of the presence of _____ coming from the ETT.What is the most common limitation to this device? And which patients does it occur most often in?
no confirmation of CO2 production.positive confirmation of CO2false negative b/c of poor cardiovascuar prefusion. Frequently in patients in caridac arrrest, hence is the reason to not only realy on one method to verify ETT placement.
ventilatory failure
occurs when the patient's minute alveolar ventilation cannot keep up with the metabolic rate or CO2 production. O2 failure usually follows when the cardiopulmonary system cannot provide adequate O2 needed for metabolism
The physiologic processes of the body are dependent upon and highly responsive to the acid levels of the blood and tissues. These acid levels are also known as:
ph
Which of the following is the most common baseline variable?
pressure
During mechanical ventilation, one method to evaluate compliance change is to use the:
pressure-volume waveform.