anesthesia monitoring-VET CLIN TECH

What does SpO2 measure?

% of Hgb thats oxygenated

what is SaO2

% of hgb binding sites occupied by O2

So2 (SaO2)

% oxygen saturation

2 different wavelengths are transmitted in pulse ox

-O2 saturation -pulse rate

when RR decreases

-commonly occurs secondary to anesthesia -caution letting RR too low

what is hypercarbia caused by

-exhausted soda lime -decreased RR -decreased respiratory min volume -bad unidirectional valve -Kinked ETT

what is increased RR due to

-hypercapnia -pulmonary dz -sx stimulus -light anesthesia -obesity

what is hypocarbia caused by

-increased RR (hyperventilate) -anesthesia too light -Xs artificial ventilation -pain -hypoxia

4 objectives of anesthesia

-lack of movement -lack of pain -lack of awareness -lack of memory

if the PaO2 is < 80 what can you consider

-lung dz -lack of O2 -poor ventilation

5 things hypothermia is due to

-muscle relaxation (cant shiver) -IVF at room temp -shaved, wet areas -open body cavity -inhaled cold gas

Stage 3 of anesthesia

-plane 2 is ideal surgical anesthesia -plane 3 is deep surgical anesthesia -plane 4 is abd breathing from OD

what are some problems that occur with SpO2

-probe dry or slipped off -skin is pigmented -icterus

predisposing factors for decreased tidal volume

-prolonged anesthesia -obesity -drugs (NM blockers) -lung dz -chest sx -head trauma -horses always (cows hyperventilate)

5 ways to prevent hypotension

-proper anesthetic depth -adequate analgesia -proper pre-meds -IVF -vasopressors

types of sensors for Pulse Ox

-reflectance probe- on rectum, tail -universal C-clamp -Lingual sensor- ear, tongue, genitals

3 steps to wean off manual ventilation

-stop gas, continue O2 -slow decrease of bagging frequency (or turn down ventilator) -until brain tells P to start breathing

1 breath =

1 inhale + 1 exhale

tidal volume awake

10-15 ml/kg (we will use 10 for math)

what is the normal systolic BP in SA

100-160 mm Hg maintain > 80 mm Hg under anse

tidal volume for anesthesia

25% less

what is the normal ETCO2

35-45 mm Hg

what do you want ETCO2 at during surgery

40 mm Hg

when bagging what do you breath at

6-12 / min

anes normal RR range

8-20 / min

normal MAP awake

85-120 mm Hg

what is a normal MAP

85-120 mm Hg

normal SaO2

97% arterial

what do you keep manometer at

< 20 mmH2O < 40 in LA

Normal CVP

< 8 cmH2O

normal MAP anesthetized

> 70 mm Hg

what should SpO2 be

> 97% -< 90% needs tx

Diastolic pressure

BP when hear is filling

systolic pressure

BP when heart is contracting

what drives breathing

CO2

Hgb is the

Fe-containing protein in RBCs

leads of an EKG on SA

Green and white on the right Smoke over Fire

what are you monitoring with circulation

HR, rhythm, pulse, CRT, MM, BP

what are some things you need when monitoring circulation

HR- palate heart and pulse stethoscope esophageal stethoscope EKG Blood pressure

Direct blood pressure

IV in artery- rarely used, invasive, difficult but technically the best

hypercarbia

Increased carbon dioxide level in the bloodstream.

hypercarbia

Increased carbon dioxide level in the bloodstream. - > 45 mmHg

what are you monitoring with oxygenation

MM, Hgb, PaO2

respirations

O2 into tissue Co2 out

what happens to O2 saturation when PaO2 goes up

O2 saturation goes up

indirect blood pressure

Oscillometric or Doppler equipment -both use cuff and sequentially occlude and release arterial blood flow

what are you monitoring with ventilation

RR and depth, ETCO2, PaCO2, pH

is bagging a P with machine vs Ambu bag different

YES

Sinus Arrhythmia

abnormal rhythm related to breathing okay, except concern in cats

sterile

absence of all MOs

asepsis

absence of pathogenic microorganisms that cause infection

what does the probe read for aa SpO2

absorption of light in vessels -also measures pulsations in arterioles

what can a rise in PaCO2 lead to

acidosis

Tidal volume

amount of air in single breath

what does pale MM mean

anemia or vasoconstriction (from anesthesia)

Stage 4 of anesthesia

apnea circulatory collapse imminent death

what blood gas does ETCO2 reflect

arterial blood gases

RR is measured

as breaths per min

hands on

auscultation palpate pulses check MM watch reservoir bag jaw tone smell gas leak palpebral reflex

reflexes

automatic rxn to stimulus without awareness

explain MAP

average pressure in a P arteries during one cardiac cycle -kind of an average of systolic and diastolic

simple down doppler blood pressure

basically a crystal sends out sound waves and another crystal receives it. these waves bounce off RBCs and are then interpreted electronically forming the whoosh sound heard

Monitoring

best done with hands on exam and monitors

postive pressure

by ventilator or Bagging

what is CVP

central line into anterior vena cava -assesses blood return to the heart

how are eyes rated at light and deep anesthesia

central position

CVP

central venous oressure

fibrillation

chaotic, irregular contractions of the heart, as in atrial or ventricular fibrillation

is body temp increased or decreased under anesthesia

decreased

decreased tidal volume

decreased O2 for tissue

hypoxemia

deficient amount of oxygen in the blood

what causes muscle rigidity so used with benzos to relax

dissociative ie ketamine

Bradycardia

due to drugs or a heart condition

tachycardia

due to too little drug, surgical stimulation, drug rxn, heart condition

auricular

ear flick sensitivity

resp character

effort and length of breaths

ETCO2

end tidal CO2

mainstream

evaluates as air through airway

what will a too narrow cuff do

false hight

what will a too wide cuff do

false low

do you have increased or decreased breaths under anesthesia

fewer breaths

where is O2 carried

free in plasma or attached to Hemoglobin

pulse strength

from Arties (lingual, femoral, carotid, dorsal MT, digital)

what are three things you could suspect if you smell gas

from around the tube leak in system bag is off

what happens to pupils with death

fully dilated

laryngeal (swallow)

gone for intubation -extubate when returns

pulse deficit

heartbeat w no palpable pulse

Hgb

hemoglobin

what can decreased tidal volume lead to

hypercarbia

what is something common you see with BP under anesthesia

hypotension

some causes of Hypotension

hypovolemia heart dz XS vasodilation anesthetic depth GDV

what are some cons using the oscillometer

inaccurate in cats and small dogs pressure extremes low BP, high HR moving P

is oscillometeric BP accurate

inaccurate in cats and small dogs -inaccurate with hypotension, arrhythmia, tachycardia, shivering

Stage 1 of anesthesia

induction losing consciousness, struggling

capnometer

instrument used to measure carbon dioxide

hypocarbia

insufficient carbon dioxide = <35 mmHg

heart block

interruption in a beat. varied risk

what helps estimate anesthetic depth

jaw tone used for intubation

what does string pulse mean

large difference in systolic/ diastolic

what should CRT time be

less than 2 sec

what does an EKG do

look for abdnormal HR and rhythm

stage 1

loss of consciousness

stage 2

loss of muscle movement

stage 4

loss of reflexes, flaccid muscle tone, collapsing heart function, dying

what could a delayed CRT mean

low BP increased epinephrine domitor shock!

oscillometeric BP

machine inflates and deflates the cuff- and computer senses pulsations in the artery. pressures measured at pulse and relaxation

2 types of ETCO2 sensors

mainstream sidestream

anesthetist

may be alone with surgeon or with additional OR nurses

MAP

mean arterial pressure

MAP

mean arterial pressure average BP during full cardiac cycle

SpO2

measures SO2 (saturation of Hgb)

systolic BP

measures pressure on arteriole when heart contracts

diastolic BP

measures pressure on arteriole when heart relaxes

sphygmomanometer

measures pressure within the cuff

some sites for BP

metacarpal - median palmar metatarsal- median planter dorsal tarsus- dorsal pedal ventral tail- coccygeal

ventilation

movement of gas in and out of alveoli

what happens to pupils w the deeper anes

mydriasis

cuff width

needs to be 30-50% of limb circumference

what happens to SaO2 and PaO2 if anemic

normal SaO2 low PaO2

when would you routinely bag P

once 5-10 min

What is PaO2 dependent on?

oxygen in alveoli and health of lungs

SaO2

oxygen saturation in arteries in %

atelectasis

partial collapse of alveoli from inadequate air -common to down or dependent lung

PaO2

partial pressure of oxygen in arteries in mm of Hg

PvO2

partial pressure of oxygen in venous blood -PaO2> PvO2

pedal (paw withdrawal)

pressure to toe -must distinguish from pain rxn -useful at induction

palpebral (blink)

protects eye from injury -useful in surgery

controlled ventilation

provide all O2 no spontaneous breaths (Ie ventilator)

when doing manual ventilation what do you use to measure

pulse ox and capnograph to monitor

what do you use for SpO2

pulse oximetery

what does ventilator replace

rebreathing bag

HgB

red protein that transports oxygen

muscle tone

relaxed by anesthesia

when is O2 content measurement greatest

right after O2 is picked up by blood in lungs

what does pink MM mean

see Hgb in RBC in capillaries in non pigmented body area

what does the PLR do w increased anesthesia

slows

assisted ventilation

some gas supplied, patient breathing on own (ie bagging the patient)

agonal breathing

spasmodic diaphragm contractions, not breaths. dying.

stage 3

surgical anesthesia

what is the whoosh sound determined by

the number and velocity of RBCs

normal sinus rhythm

the regular rhythm in awake and anesthetized

do eyes change position w ketamine

they may never change

Resp. Min. Volume

tidal volume x RR/ min -amt of air that moves in and out in 1 min

PO2 (or PaO2)

unbound O2 in plasma in mm Hg

Stage 2 of anesthesia

unconsciously "fighting" the anesthesia by vocalizing, struggling. -ideally pass quickly through this stage

why is oscillometeric inaccurate

underestimates high values, overestimates low

corneal

used more to confirm death

sidestream

vacuum draws breath down small tube to main unit

eye are rotated

ventral under moderate anes

vpc

ventricular premature contraction -one wide and bizarre QRS complexes 3+ VPCs in a row - tx w lidocaine

V-tach

ventricular tachycardia

leads of and EKG on horse

white - right jugular furrow black - below white in furrow red- left ventral thorax at heart

does the partial pressure differ from venous to arterial blood

yes

is the relationship b/w PaO2 and PO2 related

yes, directly related