L2: Monitoring In Anesthesia (Shih)

Question 1

Shark fin capnograph means:**

Answer 1

Upper airway obstruction!

• p having hard time breathing OUT
• asthma, kinked ETT, mucus plug in ETT, etc.

Question 2

What does it mean when capnograph baseline doesn’t go to 0?

Answer 2

1) bad valve (rebreathing)
2) low o2 flow (non-rebreathing)
3) bad soda scrub

Question 3

Most important monitor during CPR***

Answer 3

Capnograph

Question 4

Capnograph useful for detecting LOW PERFUSION TO LUNG, like for ex:***

Answer 4

CO and PTE

Question 5

Types of metabolism that –> low CO2

Answer 5

Coma
Hypothyroidism
Low temperature

Question 6

How can pulmonary perfusion –> low CO2?

Answer 6

Decreasing CO, MAP
Hypovolemia
CPR
PTE

Question 7

What changes in ventilation –> low CO2?

Answer 7

Hyperventilation
Apnea
Pulmonary edema

Question 8

What changes in metabolism –> high CO2?

Answer 8

Fever
Tourniquet
Seizure
Hypermetabolism (MH)

Question 9

What changes in pulmonary perfusion –> high CO2?

Answer 9

Increase CO

Question 10

What changes in ventilation –> high CO2?

Answer 10

Hypoventilation

Rebreathing

Question 11

What does it mean when capnograph has normal waves in gradually increasing height?

Answer 11

• build up of CO2 (due to hypoventilation or hypermetabolism)
• tx: ventilate the patient

Question 12

What does it mean when capnograph has normal waves with gradually decreasing height?

Answer 12

-hyperventilation, low blood flow, PTE, low CO

Question 13

What does it mean when capnograph has normal waves with gradually decreasing height and reaching flatline?

Answer 13

• disconnection
• apnea
• total obstruction
• cardiac arrest

Question 14

Capnograph is extremely sensitive to heart stopping***

Answer 14

Able to tell you if you are doing a good job w/ CPR or not, for ex.

Question 15

What is #1 thing to gain from ECG?

Answer 15

RHYTHM of the heart, ie. How fast or slow it is

Question 16

Pulse oximetry measures:***

Answer 16

• Hemoglobin saturation
• not reliable for alerting hypoxia
• only alerts if PaO2 below 60 mmHg! (Or 90% saturation)***

Question 17

Advantages/disadv. of Oscilometric blood pressure machine

Answer 17

Adv:

• gives systolic, diastolic, mean
• good for routine anesthesia

Disadv.:

• only reads q3 mins.
• has more margin of error the more hypotensive the patient becomes

Question 18

Advantages/disadv. of Dopper blood pressure machine

Answer 18

Adv:

• robust, reliable
• best for ER env. W/ sick animals

Disadv:
-only gives systolic

Question 19

Advantages/disadv. of PetMap blood pressure machine

Answer 19

Very quiet, good for GP for awake cats/dogs

Disadv: not good for sick animals

Question 20

Blood flow (Q) =

Answer 20

Q = BP/SVR

Question 21

Tx of low BP during anesthesia

Answer 21

• fluid support
• inotropes (MOA: alter the energy of muscular contractions)
• decrease inhalants

Question 22

Pulse alternans def. and causes and tx

Answer 22

Alternating strong and weak pulse. Causes:

• LV systolic impairment
• cardiac tamponade (reduced ventricular filling due to pericardial fluid)
• aortic valve dz

Tx: give fluids (heart is getting emptied of blood and lungs are compressing heart)

Question 23

CO =

Answer 23

CO = BP/SVR

*always consider if p is vasoconstricted or not in relation to BP

Question 24

Tx for hypotension***

Answer 24

• decrease inhalant
• fluids
• inotropes

Question 25

Blood pressure does not always tell you about PRE LOAD***

Answer 25

:)

Question 26

Pre load monitoring

Answer 26

- CVP - Echo - gold standard - Pulse pressure variation - the up and down of the flow; pulse ox can give

Question 27

normal Central venous pressure

Answer 27

0-12 cmH2O Low:too low of volume; needs fluids High: too much volume for heart to handle *can use pulse ox to get pulse variation index, then gauge how much fluids you need to give off that. Higher the PVI, more fluids you need.

Question 28

CVP is NOT accurate to tell you about pre-load***

Answer 28

:)

Question 29

Value of lactate in anesthesia

Answer 29

- has prognostic, therapeutic, and diagnostic value - can dx septic abd - cleared by LIV normally - indicates balance of O2 delivery and O2 consumption

Question 30

Lactate drop correlates with better prognostic***

Answer 30

:)

Question 31

Capnograph --> resp. And cardio info BP --> adequate after load Pulse variation --> fluid response Lactate --> tissue oxygen

Answer 31

:)

Question 32

See oxygen consumption graph

Answer 32

:)

Question 33

2 types of capnographs

Answer 33

1) mainstream (sensor in ETT) 2) sidestream (sensor in machine) - less fragile, good for academia/exotics