Special Testing & Calibration Procedures A

Question 1

In an ABG, which variables are calculated?

Answer 1

O2sat and bicarbonate

Question 2

What is the gold standard for diagnosing GERD?

Answer 2

Esophageal pH monitoring

Question 3

How do you tell when an esophageal catheter is in the right place?

Answer 3

Advance catheter until the pH drops. Then pull pack untili pH normalizes. Then pull back another 5 cm.

Question 4

What’s the best way to determine respiratory effort?

Answer 4

Esophageal manometry

Question 5

What is a montage?

Answer 5

The channel layout in a sleep study.

Question 6

In a typical sleep study montage, the low frequency is usually set for ___.

Answer 6

0.3 Hz

Question 7

Low frequency on the body & snoring is set for ___.

Answer 7

10 Hz

Question 8

Low frequency for nasal airflow, thoracic, and abdomen is set for ___.

Answer 8

0.1 Hz

Question 9

The high frequency is usually set for ___.

Answer 9

35 Hz

Question 10

The high frequency for the ECG is ___.

Answer 10

70 Hz

Question 11

The high frequency for the body and snore sensors are usually set for ___.

Answer 11

100 Hz

Question 12

The high frequency for the nasal airflow, thoracic, and abdomen is usually set for ___.

Answer 12

15 hz

Question 13

The sensitivity on all instruments is ___.
The sensitivity on the ECG is ___.
The sensitivity on the chin is ___.

Answer 13

7 uV/mm
ECG is 20 uV/mm
Chin is 2 uV/mm

Question 14

What is the sampling rate for all equipment?

Answer 14

500 hz

Question 15

What is the sampling rate for the nasal airflow, thoracic, and abdomen?

Answer 15

100 Hz

Question 16

What is the sampling rate for the SpO2?

Answer 16

25 Hz

Question 17

What does the Nyquist Theorem state?

Answer 17

The sampling rate must be at least twice as much as the signal bandwidth.

Question 18

What are the montage settings for all the electrodes except ECG? (LFF, HFF, Sensitivity, and Sampling Rate)

Answer 18

LFF = 0.3
HFF = 35
Sensitivity: 7 uV/mm
Sampling rate: 500 Hz

Question 19

In a referential montage, each channel represents the difference between a certain electrode and a ___.
In a bipolar montage, each channel represents the difference between ___.

Answer 19

Reference electrode.

Two adjacent or exploring electordes.

Question 20

Which type of montage is most often used in polysomnography?

Answer 20

Referential montage

Question 21

When do you see bipolar montages?

Answer 21

EMG and ECG

Question 22

What is a time constant?

Answer 22

The time in seconds that it takes for a waveform to drop to 37% of its calculated amplitude.