Anesthesia Machine Flashcards
Describe the purpose of the fail-safe valve
on the anesthesia machine.
The fail-safe valve prevents the delivery of hypoxic gas mixtures from the machine in the event of failure of the oxygen supply. The fail-safe valve goes by many other names- the oxygen failure safety valve, oxygen failure safety device, low-pressure guard ian system, oxygen failure protection device. pressure sensor shutoff system or valve, pressure sensor system, and nitrous oxide shut off valve.
At what pressure does the fail-safe valve shut off the flow of N20 or other gases?
Line pressures ofless than 30 psi will usually close the flow of all gases, except oxygen, to the common gas outlet.
When does the positive pressure relief valve
of the scavenger system open?
If flow of waste gases into the vacuum source is insufficient and the reservoir bag distends. the positive pressure valve opens and vents some of the exhaled gases into room.
of the scavenger system open?
f the flow of waste gases into the vacuum system is too high and the bag collapses, the negative valve opens and lets in room air.
What type of gas can lead to delivery of a
hypoxic mixture on a workstation equipped
with a proportioning system? What is mandatory when such a gas is present?
An inert third gas, such as He, N₂or C0₂, can cause delivery of a hypoxic mixture because contemporary proportioning systems link only nitrous oxide and oxygen.Use of an oxygen analyzer is mandatory (or referentially a multigas analyzer) if the operator uses a third gas.
What type of anesthesia machines should be
tested with a negative-pressure leak test?
Anesthesia machines with check valves should be tested with a negative pressure leak test. In 1993, the FDA implemented a universal negative pressure leak test that can be used on all contemporary anesthesia machines, regardless of the presence or absence of check valves.
Where and how is the negative-pressure leak
test performed on the anesthesia machine
during check-out?
To perform a negative-pressure leak test, a suction bulb is attached to the common fresh gas outlet and squeezed repeatedly until the bulb is fullycollapsed. The anesthesia machine is leak-free is the bulb remains collapsed for at least 10 seconds.
When the O2 flush button is pushed, what is
the liter flow rate?
35-75 Iiters/min.
You are scheduled to provide anesthesia
to a patient with a known susceptibility to
malignant hyperthermia. How will you
prepare the gas machine in anticipation of
this case?
presence of trace amounts of volatile agents in Ihe rubber and plastic components of the gas machine and in the ventilator and CO2 absorber. The following 3 actions should be taken
to prepare the gas machine for the patient with a known susceptibility to malignant hyperthermia. (1) The gas machine should be thoroughly flushed with 100% oxygen for at least IO minutes (to remove residual
traces of volalile agents from rubber and plastic components in the machine. (2) The breathing circuits and CO₂canister should be replaced. (3) Vaporizers should be drained, inactivated, or removed.
NIOSH: Halogenated Agent Alone
2 PPM
NIOSH: Nitrous
25 PPM
NIOSH: Nitrous + Halogenated Agent
25 PPM, 0.5 PPM
Gas lines proximal to flow valves are considered to be in the high-pressure circuit whereas those between the flow valves and the common gas outlet are considered part of the low-pressure circuit of the machine.
.
NIOSH: Dental Facility Nitrous
50 PPM
O2 is always in what position?
Last, most distal, most right
