Miscellaneous Monitors & Equipment

Question 1

What is the BEST method of assessing a deep neuromuscular block?

Answer 1

Post-tetanic count

Question 2

post-tetanic count (PTC) is used to assess

Answer 2

the depth of neuromuscular blockade when no twitches are present (i.e., with a deep block)

Question 3

What percent of Nm receptors must be blocked to lose T1 (no twitches)?

Answer 3

90%

Question 4

Fade occurs when the T4/T1 ratio is less than:

Answer 4

1.0

Question 5

What is the advantage of a double-burst stimulation?

Answer 5

It’s easier to detect fade with DBS than it is with TOF.

Question 6

Describe double-burst stimulation.

Answer 6

2 short bursts of 50 Hz tetanus 0.75 seconds apart

Question 7

What is post-tetanic potentiation?

Answer 7

It occurs when the twitch response is stronger after a tetanic stimulus than it was at baseline.

Question 8

Cerebral oximetry measures regional or global cerebral oxygenation?

Answer 8

Regional

Question 9

What change from baseline suggests a reduction in cerebral oxygenation?

Answer 9

A > 25% change from baseline

Question 10

Cerebral oximetry measures venous or arterial hemoglobin saturation?

Answer 10

Venous

Question 11

Name the 4 EEG waveforms and rank them from highest to lowest frequency

Answer 11

1. Beta
2. Alpha
3. Theta
4. Delta

Question 12

Alpha brain wave activity

Answer 12

Awake

Question 13

Beta brain wave activity

Answer 13

Mental stimulation, Light anesthesia

Question 14

Theta brain wave activity

Answer 14

GETA, normal sleep in children

Question 15

Delta brain wave activity

Answer 15

GETA, deep sleep, brain ischemia

Question 16

What 2 brain EEG waves are seen with GETA?

Answer 16

Delta and theta

Question 17

Burst suppression occurs during what type of anesthesia?

Answer 17

Deep general anesthesia. It can also occur during hypothermia, CPB, and cerebral ischemia.

Question 18

What MAC is required to produce cerebral isoelectricity?

Answer 18

1.5 - 2.0 MAC

Question 19

What 3 states mimic cerebral ischemia when monitoring the EEG?

Answer 19

Deep anesthesia
Hypothermia
Hypocarbia

Question 20

How does ketamine affect the BIS value?

Answer 20

Falsely elevates BIS value

Question 21

Burst suppression begins at what BIS value

Answer 21

20

Question 22

What is the BIS target value for general anesthesia?

Answer 22

40 - 60

Question 23

What is the time lag between measuring the EEG and computing the BIS value?

Answer 23

20 - 30 seconds

Question 24

Describe the function of the alarm of the line isolation monitor.

Answer 24

The alarm sounds when the OR power supply becomes grounded.

Question 25

What is macroshock?

Answer 25

Macroshock is a comparatively larger amount of current that is applied to the external surface of the body (the impedance of the skin is not bypassed).

Question 26

What is microshock?

Answer 26

Microshock is a comparatively smaller amount of current that is applied directly to the myocardium (the impedance of the skin is bypassed).

Question 27

What is the function of the line isolation monitor?

Answer 27

It tells you when the OR becomes grounded and how much current could potentially flow through you or a patient if a second fault occurs.

Question 28

The isolation transformer sits between what entity and the OR?

Answer 28

Power company

Question 29

If an LIM alarm sounds what action should be taken first?

Answer 29

The last piece of equipment that was plugged in should be unplugged.

Question 30

Microshock value that is enough to cause Ventricular fibrillation

Answer 30

100 uA

Question 31

What is the real name for the "grounding pad"?

Answer 31

Return pad or return electrode. Grounding pad is a misnomer. It does NOT ground the patient.

Question 32

Which produces a smaller electrical circuit in the body - a monopolar or bipolar electrocautery?

Answer 32

Bipolar. The circuit is limited to the tips of the bipolar forceps. There's no need for a return pad elsewhere on the body.

Question 33

Why is the return pad so large?

Answer 33

A large, low impedance surface area is needed for the electrical current to exit the body and return to the power generator.

Question 34

Why doesn't electrocautery produce microshock?

Answer 34

The surgical electrocautery device delivers a high frequency current (500,000 - 1 million Hz). These higher frequencies don't affect excitable cells. Therefore, ventricular fibrillation is not a risk.

Question 35

When assessing train-of-four, what degree of post-junctional nicotinic receptor blockade is consistent with the disappearance of T4?

Answer 35

80%

Question 36

A deep hypnotic state is defined as a bispectral index value less than:

Answer 36

40

Question 37

Which method provides the GREATEST margin of safety against the risk of macroshock in the operating room?

Answer 37

Isolate the ground from the main power supply

Question 38

During anesthetic maintenance, the appearance of delta waves should raise suspicion of:

Answer 38

cerebral ischemia.

Question 39

When using the patient safety index monitor, what is the recommended range for anesthetic maintenance?

Answer 39

25 - 50

Question 40

Voltage is similar to what corresponding hemodynamic variable

Answer 40

Blood pressure

Question 41

Current is similar to what corresponding hemodynamic variable

Answer 41

Cardiac output

Question 42

Impedance is similar to what corresponding hemodynamic variable

Answer 42

Systemic vascular resistance

Question 43

​Ohm's law

Answer 43

Voltage ​ = ​ Current ​ x ​ Impedance

Question 44

Max allowable current leak in the OR

Answer 44

10 uA

Question 45

In the operating room what is grounded?

Answer 45

Equipment

Question 46

In the operating room what is NOT grounded?

Answer 46

Power

Question 47

Purpose of the line isolation monitor:

Answer 47

alarms when the operating room is grounded.

Question 48

The LIM will alarm when it detects how much leak?

Answer 48

2 - 5 mA of leak currect

Question 49

When using a bipolar electrocautery unit, the electricity exits the patient's body through the:

Answer 49

Forceps.