Anesthesia Machine Flashcards
What is the most important monitor on the machine?
O2 analyzer
Which monitor helps you detect a disconnect in the machine?
ETCO2 (capnography)
What is the O2 calibrated to?
21% O2 (room air)
What monitoring gives you gas exchange information?
SpO2 - pulse oximetry
What is the pressure of the O2 flush valve?
When do you use the O2 flush? (2)
35-75 lpm
- daily check
- expiratory phase to fill bellows (only sometimes)
What is the pressure in an O2 cylinder and an N2O cylinder? How many liters of O2 in O2 cylinder?
2000 PSI
745 PSI
625-700 liters
What is the pressure of the pipeline gas?
50 PSI
Which institute regulates anesthesia machines from 2000 and older? 2000 and newer?
- ANSI - American National Standards Inst
2. ASTM - American Society for Testing and Materials
When do you perform complete machine checks and breathing circuit checks?
Machine - daily
Circuit - before each case
What are the 5 purposes/pathways for O2 in the machine?
- fresh gas flow to flowmeters
- O2 fail-safe mechanism (N2O)
- O2 low pressure alarm
- O2 flush valve
- Compress bellows to drive ventilator
What is DISS, KISS, and PISS?
Name the right PISS for each gas and what is the size for the pins?
Safety features when hooking up connections:
1. diameter index safety system for pipeline (body, nipple, nut connection)
2. key index safety system for vaporizer
3. pin index safety system for cylinder tanks:
O2 = 2 + 5, N2O = 3 + 5, Air = 1 + 5
-pin diameter = 4mm, length = 6mm
What is in the high pressure system?
- cylinder tanks
What is in the intermediate pressure system?
- O2 flush valve
- pipeline and switch
- O2 low pressure fail device
- flow meter control VALVES
- pressure regulators
What is in the low pressure system?
SLIGHTLY ABOVE ATM
- flow meter tubes
- hypoxia prevention device
- vaporizers and its manifold
- common gas outlet
- pressure relief devices
- outlet check valve (undirectional valves)
What does the O2 pressure sensor shut off valve do?
It will shut off/turn down N2O if it loses pressure in O2
Describe the 2 types of O2 pressure sensor shut off valves:
- proportional link
- threshold valve
- will decrease N2O proportionally to decreased pressures in O2, if O2 is too low, it will shut off N2O
- if detects loss of O2 below threshold, N2O will shut off
Name 3 safety mechanism on flowmeters.
- color coded system (O2 = green, N2O = blue, Air = yellow)
- knobs (O2 is different)
- O2 flowmeter is always furthest downstream
Which pressure system is most vulnerable to breakage?
low pressure system
What is the negative pressure leak test?
- master switch, flow valves, vaporizers OFF
- apply suction bulb to common gas outlet
- squeeze bulb til it collapses = vaccuum of neg pressure
- if bulb stays collapsed for 10 sec = PASS, otherwise fail and there may be a leak in the system
What does the circle system check evaluate?
breathing circuit (common gas outlet to the y-piece)
How do you perform a (breathing) circuit leak test?
-occlude Y-piece
-close APL valve
-use O2 flush valve to increase pressure to 30 cm of H2O
(if able to reach 30 cm then it is patent)
How do you perform a flow test?
- attach breathing bag (lungs) to y-piece
- turn on vent
- assess unidirectional valves
What is the flow of gas in a simple circle system? (9 steps)
inspiration: 1. gas enters from common gas outlet 2. thru insp limb one-way valve 3. thru insp breathing tube (limb) 4. thru y-piece to patient expiration: 5. from patient to exp breathing tube (limb) 6. thru exp limb one-way valve 7. in/out of reservoir bag 8. CO2 absorber (top to bottom) 9. back towards patient
