Anesthesia Machine Flashcards
What percentage of air is O2?
21%
What is the metabolic requirement for oxygen?
5-10 mL/kg/min
What is the capacity of an E cylinder?
What is the total pressure?
660 L
2200 psi
What is the capacity of an H cylinder?
What is the total pressure?
6600 L
2200 psi
How would you calculate the remaining O2 in an E cylinder?
How would would calculate the minutes remaining?
2200 psi/660 L = psi left in E tank/X L
minutes remaining = X L/flow L/min
What are the functions of the regulator?
- pressure-reducing valve
- decreases tank pressure to a constant pressure of 50 psi, which is supplied to the flowmeter
- prevents pressure fluctuations as the tank empties
What are the functions/features of the flowmeter?
- controls rate of gas flow through the vaporizer
- reduces gas pressure from 50psi to 15psi
- gas-specific
- read flow at middle of ball or top of bobbin
What are the functions of the quick flush?
- delivers O2 from the intermediate pressure area of the machine (50psi)
- bypasses the vaporizer, so contains no anesthetic agent
VOC features
- all modern vaporizers are out of circuit
- carrier gas is from flowmeter
- delivers precise anesthetic concentration
- agent-specific
VIC features
- carrier gas is patient’s expired gases
- no precise concentration
- not agent specific
What are the names of the two re-breathing systems?
circle
universal F
What is mechanical dead space?
the portion of the anesthesia circuit where bidirectional flow is occurring
What are the disadvantages of a re-breathing system?
- higher resistance due to valves
- changes in anesthetic gas concentration occur slowly
- more components, so more potential for leaks
What are the components of a re-breathing system?
- fresh gas input and O2 flush
- uni-directional valves
- breathing hoses
- CO2 absorber
- APL pop-off valve
- reservoir bag
What are the signs of a patient with CO2 absorbent exhaustion?
- increased RR
- increased HR and BP
- red mucus membranes