Anesthesia Machine, Breathing Circuits, Inhalants (Pt. 1 &2)

Question 1

Where does the breathing circuit begin?

Answer 1

Fresh gas outlet

Question 2

Most common portable tank? Pressure and volume?

Answer 2

E tank

2,000 psi, 700L

Question 3

Most common bulk tank? Pressure and volume?

Answer 3

H tank

2,000 psi, 7,000L

Question 4

Name the cylinder color for:

1) Oxygen
2) NO
3) Nitrogen
4) medical-grade air

Answer 4

1) green
2) blue
3) black
4) yellow

Question 5

Which safety system prevents hooking up a PORTABLE tank to the incorrect yoke?

Answer 5

Pin index safety system

each type of gas tank has holes in unique locations that align with pins on the corresponding gas line

Question 6

Working pressure entering into the anesthesia machine?

Answer 6

45-50 psi

Question 7

2 mechanisms that can be present on WALL OUTLETS to prevent hooking up supply lines to the wrong source?

Answer 7

Diameter Index Safety System

Quick connect

Question 8

How does activation of the oxygen flush valve affect anesthetic concentrations in the system?

Answer 8

Decreases (dilutes) them

Question 9

Which part of the anesthesia machine enables the liquid anesthetic to become a vapor and mix with oxygen?

Answer 9

Anesthesia vaporizer

Question 10

Common outflow for the vaporizer and oxygen flush?

Answer 10

fresh gas outlet

this is also where the breathing circuit connects

Question 11

4 classifications of breathing circuits?

Answer 11

1) open
2) semi-open (non-rebreathing)
3) semi-closed (circle)
4) closed (circle)

Question 12

4 advantages of non-rebreathing over circle system

Answer 12

1) low resistance
2) simple (low failure)
3) no distance limitations
4) immediate control of inspired concentration

Question 13

Main difference between semi-closed and closed circuit?

Answer 13

in semi-closed, FGF exceeds patient’s metabolic requirement

Closed only supplies enough to meet patient’s metabolic needs

Question 14

Purpose of Sodasorb and what are the by-products of its interaction with CO2?

Answer 14

Sodasorb scavenges CO2 from expired gas

produces water and heat

Question 15

2 purposes of APL (pop-off) valve?

Answer 15

1) vents excess gas from circuit

2) close to provide patient with manual ventilation

Question 16

This structure of an ET tube provides a secondary airway should the primary lumen become occluded

Answer 16

Murphy eye

Question 17

T/F: The cuff on an ET tube will eliminate the risk of aspiration entirely

Answer 17

False

*cuff mainly serves to reduce leaks for positive pressure ventilation

Question 18

Name two advantages of ISO over SEVO

Answer 18

Iso is more potent and costs less

COST= PRIMARY advantage

Question 19

Name one advantage of SEVO over ISO

Answer 19

It’s less soluble (works faster)

Less soluble= good; less will go to blood and other tissues…more to brain!

Question 20

Both SEVO & ISO are administered as _____

Answer 20

vapors

Question 21

Vapor pressure denotes the ability of a substance to ______

Answer 21

evaporate

higher vapor pressure=more likely to evaporate

Question 22

In a mixture of gases, the pressure exerted by one gas if it occupied the space alone?

Answer 22

Partial pressure

Question 23

How to calculate partial pressure?

Answer 23

multiple the % of the gas of interest by the atmospheric pressure

Question 24

Clinically useful way to record the amount of inhalant being administered to a patient?

Answer 24

Volume percent

Question 25

Blood: gas PC determines?

Answer 25

induction and recovery

*lower PC= less soluble (less molecules in blood)= faster induction & recovery

Question 26

Oil:gas PC determines?

Answer 26

Potency

cannot determine induction speed using this

Question 27

Time constant = ?

Answer 27

Volume(L)/ flow (L/min)

time it takes to fill a container

Question 28

% of changes after:
1 time constant?
4 time constants?

Answer 28

after 1: 63% changed

after 4: 98% changed

Question 29

Rank order of distribution of inhalants to the 4 different tissue groups (most saturated to least)

Answer 29

vessel rich (brain & viscera)
muscle
fat
vessel poor (cartilage, bone)

Question 30

Name 2 factors that influence alveolar concentration?

Answer 30

1) concentration of inhaled anesthetic

2) alveolar ventilation (depth of breath)

Question 31

What measurable variable reflects the partial pressure of an inhalant present in the brain?

Answer 31

expired volume percent

Question 32

3 disadvantages of an oxygen concentrator?

Answer 32

1) requires electricity to work
2) doesn’t deliver pure oxygen
3) doesn’t use pressurized gas (can’t use ventilator)

Question 33

The flowmeter is measured in ______ and it’s normal range is ?

Answer 33

L/min

0.2-5L/min

Question 34

4 purposes of the breathing circuit

Answer 34

1) deliver gas mixture to patient
2) remove CO2 from patient
3) secure airway
4) provide ventilation

Question 35

4 disadvantages of non-rebreathing compared to circle system

Answer 35

1) high FGF rate ($$)
2) loss of heat and moisture
3) environmental pollution
4) harder to control manual ventilation if needed

Question 36

Two purposes of reservoir bag?

Answer 36

1) provides excess capacity to build between breaths

2) used for manual ventilation

Question 37

4 advantages of circle system over non-rebreathing

Answer 37

1) lower FGF (cheaper)
2) preserves heat and moisture
3) less pollution
4) easier to provide mechanical ventilation

Question 38

4 disadvantages of circle vs. nonrebreathing

Answer 38

1) higher resistance
2) complex (higher failure rate)
3) constrained distance
4) takes time to equilibrate circuit to new concentration

Question 39

3 advantages and disadvantages of closed over semi-closed

Answer 39

A:

1) conserves gas
2) preserves heat and moisture
3) no pollution

D:

1) longer equilibration (hrs)
2) accuracy of vaporizer
3) tricky monitoring

Question 40

Disadvantages of inhalant anesthetics (3)

Answer 40

narrow therapeutic index
expensive initial investment
doesn’t block nociceptive input

Question 41

3 factors that affect arterial concentration of inhaled anesthetics

Answer 41

1) blood:gas partition coefficient
2) cardiac output (CO) (higher=slower induction)
3) arterial-venous concentration difference (larger difference drives things to arterial side & we don’t want that… so larger difference=slower induction)