L2: Anesthesia Machine and Components (Garcia)

Question 1

how much pressure of oxygen can a tank hold?***

Answer 1

1900-2200 PSI

Question 2

regulator takes pressure of oxygen from tank down to what pressure?***

Answer 2

55-75 PSI

Question 3

slide 3 diagram

Answer 3

:)

Question 4

why can tanks carry more nitrogen?**

Answer 4

stored in liquid form at high pressure

Question 5

how many liters of oxygen and at what PSI can E tank hold?

Answer 5

660L

1900 PSI

Question 6

how many liters of nitrogen and at what PSI can E tank hold?

Answer 6

1600L

750 PSI

Question 7

how many liters of oxygen and at what PSI can H tank hold?

Answer 7

7000L

2200 PSI

Question 8

how many liters of nitrogen and at what PSI can H tank hold?

Answer 8

16000L

750 PSI

Question 9

pressure in tank is ____ proportional to volume

Answer 9

directly (for O2)

Question 10

how do you gauge how much oxygen is left in tank?

Answer 10

pressure (pressure directly prop. to volume)

Question 11

how do you gauge how much N2O is left in tank?

Answer 11

by WEIGHT (pressure will not decrease until liquid nigtrogen is extinguished)

Question 12

what color is O2

Answer 12

green (white internationally)

Question 13

what color is CO2

Answer 13

gray

Question 14

what color is N2O (laughing gas)

Answer 14

blue

Question 15

what color is He

Answer 15

brown

Question 16

what color is N2

Answer 16

black

Question 17

what color is air

Answer 17

yellow (black/white internationally)

Question 18

safety systems

Answer 18

No interchangeable connections:

-Pin Index Safety System (PISS) and Diameter Index Safety System (DISS)

Question 19

fx of flowmeter

Answer 19

• measures gas flow in L/min
• has knobs for O2 and N2O
• read at center of ball or top of float

Question 20

max O/N ratio

Answer 20

1:3

Question 21

fx of flush valve

Answer 21

-bypasses flowmeter and vaporizer and delivers oxygen at intermediate pressure (45-50 psi) at 35-70L/min to dilute the anesthetic gas

Question 22

2 locations vaporizers can be

Answer 22

VOC (vaporizer out of the circuit)

VIC (in the circuit)

Question 23

pop off valve

Answer 23

• usually left open
• closed intermittently to deliver breaths
• can be closed in the closed circuit system
• if accidentally left closed, pressure will rise inside patient’s lungs and venous return to heart decreases

Question 24

scavenger

Answer 24

• passive or active
• has a charcoal absorber that avoids environmental contamination w/ short life but does NOT absorb N2O
• in passive, pressure > barometric; cheaper, simpler; whenever pressure builds up in system, it passively leaves as negative pressure
• active has a flow inducing device and is more expensive

Question 25

2 main types of breathing systems

Answer 25

Circle (Rebreathing) System - used in most patients | Non-rebreathing system - more wasteful, no recycling of gas

Question 26

Components of circle system

Answer 26

- unidirectional valves (inspiratory and expiratory) - canister with absorber - breathing bag - rebreathing tube - pressure gauge - pop off valve

Question 27

chars. of unidirectional valves

Answer 27

- allow flow only in 1 direction - no rebreathing of CO2 (expiratory valve prevents) - may stick with moisture - may dislodge from housing

Question 28

canister

Answer 28

- houses CO2 absorbent (sodalime, baralyme) - should be >2x the tidal volume (Vt) of the patient - great source of leaks - should not be overfilled due to channeling - granules turn purple when exhausted

Question 29

MOA of sodalime and baralyme absorbents

Answer 29

- reacts with CO2 forming heat and H2O - changes color with reaction - changed when 1/2 of soda is purple - pellets become harder after reaction - caution: pellets won't stay purple forever!

Question 30

breathing bag

Answer 30

- used as a reservoir - 6x the tidal volume of the patient - used to deliver breaths manually - can be used to count RR - some protection against excessive pressure

Question 31

most to least sites of leaks

Answer 31

``` canister unidirectional valves reservoir bag hoses connections *must close pop off valve to check for!* ```

Question 32

advantages of circuit system

Answer 32

-rebreathing of expired gas after CO2 elimination -keep heat and moist -more economic (decreases O2 and inhalant used) -lower O2 flows: less env. contamination -

Question 33

disadvantages of circuit system

Answer 33

- lots of parts - more likely to leak - difficult to clean - not easily moved - controlled ventilation can lead to hypocarbia (dec. CO2 in the blood)

Question 34

chars. of semi-closed circuit system

Answer 34

- O2 is greater than p requirement - O2 flow >20ml/kg - CO2 elimination less dependent on absorbent - no nitrogen accumulation due to low flow - fast change in anesthetic concentration

Question 35

chars. of semi-closed circuit system

Answer 35

- less economic - less heat and moist conservation than closed - more pollution - high flows may increase resistance

Question 36

adv. of low flow or closed system (same machine as semi-closed circuit system, but with low flow)

Answer 36

- more economic - less pollution - keep heat and moist

Question 37

how much flow does a low flow system have?

Answer 37

8-15ml/kg

Question 38

disadv. of low flow or closed system

Answer 38

- CO2 elimination dependent only on absorbent (not on scavenger) - slower change in anesthetic conc. - may cause incorrect vaporizer output (since vaporizer is flow dependent - N accumulation

Question 39

chars. of non-rebreathing systems

Answer 39

- elimination of CO2 by high O2 flow - usually use on patients <3kg - high O2 flow (100-200 ml/kg) - Bain system most common

Question 40

adv. of non-rebreathing system

Answer 40

- light, simple, low resistance - no need for absorber - fast change in depth - inexpensive

Question 41

disadv. of non-rebreathing system

Answer 41

- wasteful - loss of heat and moisture - pollution - changes in EtCO2 (lvl of CO2 released at end of expiration) and gas analyzer readings

Question 42

can leave pop-off valve closed in closed system?

Answer 42

yes

Question 43

main use of low flow or closed system

Answer 43

to MAINTAIN animal in anesthesia

Question 44

how to check for leaks

Answer 44

- close pop-off valve - put thumb on patient's end of breathing hose - press flush valve until pressure gauge reads 30 cmH2O - pressure should hold - press flush valve - p's end of breathing hose open - reservoir bag should deflate (if inflates, means inspiratory hose is leaking)