Gas Machine pt2

Question 1

point at which fresh gas enters breathing circuit

Answer 1

fresh gas inlet

Question 2

what is a reservoir bag

Answer 2

(rebreathing bag) holds fresh and recirculated gas to be inhaled

Question 3

the inspiratory breathing tube, thro which the patient breaths, is attached to

Answer 3

the inspiratory unidirectional valve (gives fresh and recirculated breath)

Question 4

this piece attaches to the inspiratory and expiratory tubes, and endotracheal mask

Answer 4

y-piece

Question 5

this valve controls whether system is open, partial, or closed (all gas retained)

Answer 5

pressure relief valve (pop-off valve)

Question 6

what a reservoir bag is used for

Answer 6

observe respirations, confirm ET placement, manual ventilation

Question 7

formula for calculating reservoir bag size

Answer 7

tidal volume x 6

Question 8

where the pressure manometer is located and what it does

Answer 8

on top of CO2 absorber, indicates pressue in airways and lungs

Question 9

the pressure in the patients airways and lungs shouldn’t be less than

Answer 9

<15 cm H20 or <11mmHg

Question 10

to open the pop-off valve turn _____ if bag is too full

to close turn ____ if bag not full enough

Answer 10

open= counter-clockwise (L)
closed= clockwise (R)

Question 11

steps for ventilating (bagging) a patient

Answer 11

close pop-off valve, squeeze bag watching manometer, re-open valve

Question 12

what the air-intake/ neg-pressure relief valve does

Answer 12

allows room air into circuit if vacuum is detected (we don’t control)

Question 13

when would a vacuum be created (and the neg-pressure relief valve kicks on)

Answer 13

O2 tank empties or if pop-off valve is too open, reservoir bag deflates, and the animal inhaling causes a vacuum

Question 14

how long a CO2 canister lasts

Answer 14

6-8 hr of surgery (will start to turn purple)

Question 15

when to open/close moisture relief valve

Answer 15

open when machine is turned off, closed when using

Question 16

how often to change a charcoal filter system

Answer 16

6-8 hr of use, or when has gained 50 lbs in weight

Question 17

steps in testing rebreathing circuit pressue and for leaks

Answer 17

1. close pop-off
2. open O2 tank outlet valve
3. occlude opening of Y piece
4. fill rebreathing bag till pressure manometer reads 30 cm H2O (if after 10sec the pressure hasn’t dropped below 25= no leak)

Question 18

when to bag

Answer 18

• apneic or undergoing cpr
• chest cavity is open (no negative pressure)
• a neurotransmitter blocker is used (cant effectively breath)
• reflate alveoli after alectasis
• flushout CO2

Question 19

a decrease in reservoir bag movment means

Answer 19

• decreased RR or Vt
• ET cuff not inflated properly or ET too small in diameter (gas is going around)
• tube not in trachea

Question 20

why a reservoir bag may be over full

Answer 20

• O2 flow rate too high
• bag too small
• pop-off valve not open enough
• scavenging problem(not sucking enough out)

Question 21

why a reservoir bag may collapse

Answer 21

• O2 flow rate too low
• O2 tank empty
• bag too small (empties w each breath)
• pop-off valve too open
• problem w scavenging (sucking everything out)

Question 22

O2 flow rate for a rebreathing circuit

Answer 22

15-50 ml/kg/min