FREE RST Patient Setup and Instrumentation Questions and Answers

Question 1

When performing physiological calibrations prior to a polysomnogram, the technologist asks the patient to look left and then right. Which of the following channels is being primarily evaluated with this action?

Accepted Answer

Electrooculogram (EOG)

Answer

The EOG channels are used to monitor eye movements. Asking the patient to look left and right creates characteristic out-of-phase deflections in the EOG channels, verifying proper electrode placement and signal response.

Question 2

A sleep technologist measures a patient's head from the nasion to the inion, finding a distance of 36 cm. According to the International 10-20 system, what is the distance from the nasion to the Fz electrode placement?

Accepted Answer

7.2 cm

Answer

The International 10-20 system specifies that the distance from the nasion to Fz is 20% of the total nasion-inion measurement. Therefore, 20% of 36 cm is 7.2 cm.

Question 3

During a study, the technologist observes a persistent, rhythmic artifact in the EEG and EOG channels that corresponds with the patient's heart rate on the ECG channel. What is the most likely cause of this artifact?

Accepted Answer

Pulse artifact

Answer

Pulse artifact, or ECG artifact, occurs when an electrode is placed on or near a pulsating blood vessel. The electrical signal of the heart (QRS complex) is then picked up by the nearby electrode, causing a rhythmic artifact synchronized with the heartbeat.

Question 4

A patient arrives for their sleep study and reports having used a thick hair conditioner and styling gel after washing their hair. Which of the following is the most significant challenge the technologist might face during setup?

Accepted Answer

High and unstable electrode impedances

Answer

Hair products like conditioners and gels can create a barrier on the scalp, making it difficult to achieve low and stable electrode impedances. This can lead to poor signal quality from the EEG electrodes. The patient's skin and hair should be clean and dry for optimal electrode application.

Question 5

Which of the following is the primary purpose of performing bio-calibrations at the beginning of a polysomnography recording?

Accepted Answer

To verify that all sensors and electrodes are functioning correctly

Answer

Bio-calibrations involve having the patient perform specific maneuvers (e.g., blinking, moving limbs, holding breath) to generate known physiological signals. This process verifies that all electrodes and sensors are placed correctly, are functioning properly, and are accurately reflecting the patient's physiological changes before the study begins.

RST - Registered Sleep Technologist Practice Test

RST - Registered Sleep Technologist Practice Test

FREE RST Patient Setup and Instrumentation Questions and Answers