Scoring and Staging

Question 1

What are the EEG leads to detect eye movements?

Answer 1

E1 and E2

Question 2

What lead are E1 and E2 (Left and Right eye outer canthus) referenced to?

Answer 2

M2 (Right mastoid)

Question 3

Definition of slow waves

Answer 3

Peak to peak amplitude greater than 75 microvolts

Frequency 0.5 to 2 Hz

Question 4

The EEG background for REM sleep is low voltage mixed frequency but what will frequently appear and is not an arousal?

Answer 4

Alpha bursts

Question 5

Is a K complex or sleep spindles necessary to score an epoch as N2?

Answer 5

No. Once N2 has been determined (by a K complex or sleep spindle) then all subsequent epochs of low amplitude-mixed frequency will also be N2

• Unless there is an arousal
• Unless criteria met for N3 or REM

Question 6

Describe a K complex

Answer 6

• Negative sharp wave followed immediately by a positive component (per convention a negative wave goes up)
• Stands out from the background
• 0.5 seconds or longer
• Amplitude is not a criterion

Question 7

Rule for K complex associated arousal

Answer 7

Must commence no more than 1 second after the end of the K complex

Question 8

EEG criteria for vertex waves

Answer 8

• Sharply contoured negative deflection (upward on EEG)
• Most often in central leads
• Usually seen in N1 sleep

Question 9

EEG criteria for a slow wave

Answer 9

• At least 75 microVolt peak to peak amplitude
• 0.5 to 2 Hz (subset of delta: 1 - 4 Hz)
• Defining characteristic of N3 sleep

Question 10

What are the sensors needed to detect:

• Apnea
• Hypopnea

Answer 10

Apnea = Oronasal thermal sensor (thermistor or thermocouple)

Hypopnea = Nasal pressure transducer (more sensitive than a thermal sensor)

Question 11

What are the AASM criteria for scoring an apnea?

Answer 11

• Drop in the peak signal excursion by >/= 90% of present baseline using an oronasal thermal sensor, PAP device flow or an alternate apnea sensor
• Duration of drop is >/= 10 seconds
• Drop in Sa02 is not a criteria

Question 12

What are the AASM rules for scoring a hypopnea? Rules 1A and 1B

Answer 12

Both

• 30% or > drop in peak signal excursion from baseline
• 10 or > seconds

1A

• 3% drop in SaO2 or associated with an arousal

1B

• 4% drop in SaO2 and no arousal

You can use one or the other in scoring a study but not both

Question 13

What is normal REM latency?

Answer 13

90 - 120 minutes

Question 14

What has to happen to end N2 sleep?

Answer 14

• Arousal
• Wakefulness
• Transition to N3
• Transition to REM
• Major body movement

Question 15

What are the rules for scoring REM sleep?

Answer 15

All of the following

• Low amplitude mixed frequency without K complexes or sleep spindles
• Low chin EMG for the majority of the epoch with concurrent REM
• REMs at any position within the epoch

Question 16

What are the rules for scoring REM sleep in the proceeding and following segments without Rapid Eye Movements?

Answer 16

All of the following

• LAMF without K complexes or sleep spindles
• Low chin EMG tone
• No intervening arousal
• Slow eye movements following an arousal or stage wake are absent

Question 17

Are sleep spindles seen in N3 sleep?

Answer 17

Yes. They can continue into N3 sleep.

Question 18

Are eye movements seen in N3 sleep?

Answer 18

Usually, no

Question 19

Criteria for N3 sleep

Answer 19

> 20% delta

Question 20

What can be used to detect hypoventilation during a PSG?

Answer 20

• PcO2 in ABG
• PcO2 via end-tidal CO2 sensor
• PcO2 via transcutaneous CO2 sensor

Question 21

What are the definitions of sinus tachycardia and sinus bradycardia in sleep?

Answer 21

Sinus tachycardia: > 90 bpm

Sinus bradycardia: < 40 bpm

(Note: This is different than during wake: 100 and 60)

Question 22

What are the 2 different sensors on PSG for hypopnea and apnea respectively?

Answer 22

Pressure or PTAF = Pressure transducer for hypopnea

Flow or Airflow = Thermistor for apnea

Question 23

What is the rule for a Major Body Movement with alpha?

Answer 23

If alpha is present for any part of an epoch with a MBM then it is scored as state Wake

Question 24

What is the rule for an epoch with a Major Body Movement without alpha?

Answer 24

The epoch is scored the same stage as the epoch that follows it

Question 25

What is used to measure chest and abdominal movements?

Answer 25

Inductance plethysmography (not piezoelectric belts)

Question 26

Where on the EEG are slow waves and K complexes typically seen?

Answer 26

Frontal leads

Question 27

Where on the EEG are sleep spindles typically seen?

Answer 27

Central leads

Question 28

Where on the EEG are theta waves typically seen?

Answer 28

Central and temporal leads. Usually seen in N1 and REM

Question 29

Where on the EEG are vertex waves typically seen?

Answer 29

Central leads

Question 30

Where on the EEG are sleep spindles typically seen?

Answer 30

Central

Question 31

What is the frequency range for sleep spindles?

Answer 31

11 - 16 Hz

Question 32

EEG criteria for arousals

Answer 32

* Abrupt shift in EEG frequency for at least 3 seconds * At least 10 seconds of stable sleep preceding * If during REM must have at least 1 second of increased chin EMG during episode

Question 33

What is the Respiratory Disturbance Index (RDI)?

Answer 33

RERA + AHI

Question 34

Criteria for RERA

Answer 34

All of the following * \>/= 10 seconds * Increased respiratory effort or flattening of inspiratory portion of nasal pressure (diagnostic) or PAP device flow waveform * Arousal from sleep * Not an apnea/hypopnea

Question 35

Criteria for hypoventilation

Answer 35

Either of the following: * PcO2 increases \> 55 mm Hg for 10 or more minutes * An increase \>/= 10 mm Hg PcO2 during sleep (compared to awake supine) to a value \> 50 mm Hg for 10 or more minutes

Question 36

Respiratory rules in children (\< 13 y/o) Obstructive Apnea

Answer 36

* Event lasts for at least 2 missed breaths * 90% fall in signal amplitude for 90% of the respiratory cycle compared to baseline * Continued respiratory effort occurs throughout the period of decreased airflow

Question 37

Respiratory rules in children (\< 13 y/o) Hypopnea

Answer 37

* At least 30% fall in nasal pressure signal * At least 2 missed breaths * Fall in nasal pressure lasts at least 90% of hypopnea duration * Associated with arousal or at least 3% desaturation

Question 38

Respiratory rules in children (\< 13 y/o) Hypoventilation

Answer 38

PcO2 \> 50 mm Hg for \> 25% of the sleep time

Question 39

Respiratory rules in children (\< 13 y/o) Central apnea

Answer 39

* Drop in thermal signal by \>/= 90% in amplitude and duration * Plus one of the following * Event lasts \>/= 20 seconds * Events last duration of what would be 2 pre-event breaths and is associated with an arousal or a \>/= 3% O2 desat * Events last duration of what would be 2 pre-event breaths and is associated with a decrease in HR to less than 50 bpm for at least 5 seconds or less than 60 bpm for 15 seconds (infants under 1 year of age only)

Question 40

Respiratory rules in children (\< 13 years old) Mixed apnea

Answer 40

* Drop in thermal signal by \>/= 90% in amplitude and duration * Event lasts for 2 breaths (pre-event baseline) and * Absent respiratory effort during one portion of the event and * Presence of inspiratory effor during another portion of the event (does not matter which comes first)

Question 41

Respiratory rules in children Scoring of hypoventilation

Answer 41

\> 25% of the total sleep time, arterial (or surrogate) PCO2 \> 50 mmHg