Anesthesia machine Flashcards
How do you calculate how much O2 remains in the tank?
L= pressure gauge x 700 L / 2200 psi
Vaporizer Function
changes liquid anesthetic into vapor & adds a certain amount of vapor to the fresh gas.
What type pf vaporizer is most common?
Precision
What is a risk associated with using the O2 flush valve?
you can over pressurize the lungs–> pneumothorax
When should the O2 flush valve not be used?
non-rebreathing system, low volume circuit or when starting inhalant anesthetic with rebreathing system b/c dilutes anesthetic concentration
What are semi-open breathing systems
reservoir for anesthetic gas mixture, but no rebreathing of expired gas & w/o CO2 absorption (ex. non-rebreathing systems)
What is a semi-closed breathing system?
reservoir for anesthetic gas mixture, partial rebreathing of expired gas & CO2 absorption (soda lime)
What is an open breathing system?
no reservoir for anesthetic gas & no rebreathing expired gas (ex. place chloroform on gauze)
What is a closed breathing system?
reservoir for anesthetic gas mixture, complete rebreathing of expired gas without CO2 (removed by soda lime)
a. O2 flow must be between 5-10 mL/kg/min to meet the minimum patient requirement (ex. circle)
What are the characteristics of old soda lime?
hard, chalky, color change, canister cool during anesthesia
Breathing bag function?
allows accumulation of fresh & expired gas during expiration creating compliance & prevents rapid increase in pressure during expiration
How to determine the appropriate bag size?
6 x TV; TV is 10-15 mL/kg
you can use the bag equal or slightly bigger!
What is dead space? & what part of anesthesia machine contribute
Gas that does not participate in gas exchange
- Y-piece & breathing tubes
How much is enough pressure to open the lungs?
around 12-15 cm H2O is enough!
Why use non-rebreathing system in small patients?
Provides less dead space & less resistance than circle breathing systems
