6 Anesthesia Machine Flashcards
How to check low pressure leak, best test of what
Negative pressure test, bulb to common gas outlet, fails if inflates in 10 seconds. All flows and vent off, test each vaporizer (best test of vaporizer leak)
How to do high pressure leak test, how check valve affects what is tested
Close apl and pressurize to 30. If check valve- assesses breathing circuit and low p system up until valve. If no check valve- entire low pressure system
5 tasks of oxygen
02 pressure failure alarm, 02 pressure failsafe device, flowmeter, flush valve, and vent drive gas
Cylinder colors air, 02, nitrous
Air: black and white. 02: green. Nitrous: blue
Air: max p, max vol, pin
1900 psi, 625 l
O2: psi, L
1900 psi 660 l
Nitrous: psi, L, wt when full v empty
745 psi, 1590l. 20.7 lb, 14.1 lb
How to calc time left in cylinder
L/psi when full = contents remaining /psi. Then divide answer (L) by LPM flow rate
When to change nitrous tank
Any time it falls below 745 psi
Safety relief devices for cylinder
Fusible plug that melts w elev temp (bismuth, lead, tin, cadmium), valve that opens at elev pressures, a frangible disc that ruptures under pressure
Failsafe is in which system, 2 components
Intermediate. Alarm when 02 pressure below 30 psi. Stops or dec nitrous when pressure in 02 pipe falls below 20 psi
What hypoxia prevention device does
Limits n20 flow to 3x the 02 flow
Reynolds: laminar v turbulent dependent on what
Laminar- gas viscosity. Turbulent- gas density
Fi02 calc
Air flow rate x21 plus 02 flow ratex100 / total flow rate
With fresh gas coupling how to calc tidal vol delivered
Vt set on vent + fgf on insp - vol lost to compliance