Anesthesia machine 4

Question 1

Choose the statement that BEST describes the Tec 6 vaporizer (select two):
a. it is pressurized to two atmospheres
b. it uses a flow-over design
c. it is heated to 42 degrees
d. its output is increased inside a hyperbaric chamber

Answer 1

a. it is pressurized to two atmospheres
d. its output is increased inside a hyperbaric chamber

Question 2

The Tec 6 is different than a variable bypass vaporizer in that it

Answer 2

injects a precise amount of vaporized desflurane directly into the fresh gas flow

Question 3

To ensure precise vaporizer output, the desflurane vaporizer heats the liquid anesthetic to ________ and pressurizes it to _______

Answer 3

39 C and 2 atmospheres

Question 4

The Tec 6 vaporizer does not

Answer 4

compensate for changes in elevation

Question 5

With the Tec 6, a lower ambient pressure (high altitude) requires

Answer 5

a higher setting on the dial

Question 6

With the Tec 6, a higher ambient pressure (hyperbaric oxygen tank) requires

Answer 6

a lower setting on the dial

Question 7

Which device will be the FIRST to detect an oxygen pipeline crossover?
a. proportioning system
b. oxygen analyzer
c. fail-safe device
d. pulse oximeter

Answer 7

b. oxygen analyzer

Question 8

The oxygen analyzer typically resides in the

Answer 8

inspiratory limb of the breathing circuit

Question 9

The oxygen analyzer is the final defense against

Answer 9

the delivery of a hypoxic mixture

Question 10

The only safety device in the anesthesia machine that measures oxygen concentration is

Answer 10

the oxygen analyzer

Question 11

If O2 consumption increases, but O2 delivery remains constant, then it’s possible

Answer 11

to create a hypoxic mixture

Question 12

What are the three roles of the oxygen analyzer?

Answer 12

it monitors oxygen concentration (not pressure)
it can detect an oxygen pipeline crossover
it can detect a hypoxic mixture caused by a leak in the oxygen flowmeter

Question 13

The galvanic fuel-cell oxygen analyzer must be

Answer 13

calibrated daily and the components are consumable so must be replaced over time

Question 14

The paramagnetic device oxygen analyzer is

Answer 14

self-calibrating and has no consumale parts

Question 15

Compared to the galvanic fuel-cell, the paramagnetic device

Answer 15

has a faster response time

Question 16

What are the MOST critical actions to perform during an oxygen pipeline crossover? (select 2)
a. disconnect the pipeline supply
b. replace the oxygen analyzer
c. ventilate with an ambu with the auxillary oxgyen flowmeter
d. turn on the oxygen tank

Answer 16

a. disconnect the pipeline supply
d. turn on the oxygen tank

Question 17

When the oxygen analyzer alarms, it’s best to assume

Answer 17

that a pipeline crossover has occurred until other causes can be ruled out

Question 18

If you have a pipeline crossover, you must perform these two critical steps:

Answer 18

turn on the oxygen cylinder AND disconnect the pipeline oxygen supply

Question 19

The second step of a potential pipeline crossover is to,

Answer 19

verify that the oxygen concentration in the circuit is increasing; if not, ventilate the patient with an Ambu bag connected to a different oxygen tank & convert to a TIVA

Question 20

With a pipeline crossover, it is important to conserve tank oxygen by _________. If your machine uses oxygen as the ventilator drive gas, then convert to

Answer 20

using low flows; hand ventilation

Question 21

Select the true statements regarding the oxygen flush valve. (select 2).
a. the risk of barotrauma is minimized by ventilators with fresh gas decoupling
b. it will deliver a continuous pressure of 35-75 psi
c. excessive use can lead to awareness
d. it will cause the ventilator spill valve to close during inspiration

Answer 21

a. the risk of barotrauma is minimized by ventilators with fresh gas decoupling
c. excessive use can lead to awareness

Question 22

The oxygen flush valve provides a path for oxygen to travel from the

Answer 22

intermediate-pressure system to the breathing circuit

Question 23

Pressing the oxygen flush valve exposes the breathing circuit to oxygen flow of

Answer 23

~35-75 L/min.

Question 24

Pressing the oxygen flush valve exposes the breathing circuit to oxygen pressure of

Answer 24

~50 psi (pipeline pressure)

Question 25

Most manufacturers do not recommend using the oxygen flush valve for

Answer 25

jet ventilation- its use in this context is considered "off label"

Question 26

The gas from the oxygen flush does not pass through

Answer 26

the vaporizers which can dilute the partial pressure of the volatile agent and may lead to patient awareness

Question 27

During mechanical ventilation, the ventilator spill valve is

Answer 27

closed during the inspiratory phase

Question 28

Pressing the oxygen flush during the inspiratory phase

Answer 28

transfers pressure to the patient's lungs leading to risk of barotrauma

Question 29

Describe what happens to the bellows and spill valve during inspiration.

Answer 29

drive gas compresses bellows drive gas closes spill valve fresh gas form the ventilator goes to the patient

Question 30

Describe what happens to the bellows during expiration.

Answer 30

expired gas refills the bellows bellows fills completely when circuit pressure >2-4 cm H2O expire gas is directed through the spill vale to the scavenger

Question 31

Methods on anesthesia machines to minimize the risk of barotrauma include

Answer 31

isolating the tidal volume delivered to the ventilator from the flowmeters and oxygen flush valve- known as fresh gas decoupling inspiratory pressure limiter- limits the breathing circuit pressure where excess gas is vented out the scavenger

Question 32

A stuck open flush valve will result in

Answer 32

barotrauma

Question 33

What 2 functions does the drive gas on a pneumatic ventilator serve?

Answer 33

it compresses the bellows it opens and closes the ventilator spill valve

Question 34

What is the minimum expiratory pressure needed to open the ventilator spill valve?

Answer 34

~3 cmH2o

Question 35

Select the true statements about the pneumatic ventilator bellows. (select 2) a. a descending bellows is made safer by fresh gas coupling b. a descending bellows cannot rise and fall with a circuit disconnect c. a leak in the bellows may cause the reading on the oxygen analyzer to increase d. a hole in the bellows may cause barotrauma

Answer 35

c. a leak in the bellow may cause the reading on the oxygen analyzer to increase d. a hole in the bellows may cause barotrauma

Question 36

The bellows is classified by its movement during

Answer 36

expiration

Question 37

An ascending bellows_______ during expiration, and a descending bellows _______during expiration.

Answer 37

rises; falls

Question 38

The ___________ bellows design is generally regarded as safer

Answer 38

ascending bellows

Question 39

The ascending bellows design is generally safer because the

Answer 39

descending bellows continue to rise and fall if there is a circuit disconnect; newer descending bellows designs mitigate this risk

Question 40

A leak in the bellows creates a path between

Answer 40

the ventilator drive gas (the gas that compresses the bellows) and the gas inside the patient breathing circuit

Question 41

What is fresh gas flow decoupling?

Answer 41

tidal volume set on the ventilator is what the patient actually receives

Question 42

What is the equation for fresh gas flow coupling?

Answer 42

total tidal volume= Vt set on ventilator + FGF during inspiration - volume lost to circuit compliance

Question 43

A bellows leak could allow

Answer 43

anesthetic vapor to escape from the breathing circuit leading to risk of awareness