A patient on PSG shows frequent arousals but no oxygen desaturation. What channel should the technologist check next?

• Oxygen saturation

• EEG

• Nasal airflow

A patient undergoing Level III sleep study must have at least which parameters?

• EEG and video

• Airflow, oximetry, chest effort

• Leg EMG

A technologist notes paradoxical chest and abdominal movement during apnea. What is this?

• Central apnea

• Obstructive apnea

• Complex apnea

During PSG, the technologist increases low-frequency filter to 1 Hz. Why?

• To reduce sweating artifacts

• To detect apnea better

• To amplify K-complexes

A patient’s EEG shows K-complexes with spindles. Which stage of sleep is this?

• N1

• N2

• N3

A patient with obesity hypoventilation syndrome is suspected. Which channel provides best supporting data?

• Body position

• Capnography

• ECG

A PSG shows apnea without thoracic effort. What type of apnea is this?

• Central

• Obstructive

• Mixed

During HST, nasal airflow sensor detaches. Which parameter becomes unreliable?

• Oximetry

• Airflow

• ECG

A PSG shows bursts in anterior tibialis EMG during sleep. What condition is likely?

• REM behavior disorder

• Periodic limb movement disorder

• Central apnea

A patient with suspected nocturnal GERD requires which additional channel?

• Esophageal pH monitoring

• Chin EMG

• Nasal airflow