Scoring and Staging Flashcards
(41 cards)
What are the EEG leads to detect eye movements?
E1 and E2
What lead are E1 and E2 (Left and Right eye outer canthus) referenced to?
M2 (Right mastoid)
Definition of slow waves
Peak to peak amplitude greater than 75 microvolts
Frequency 0.5 to 2 Hz
The EEG background for REM sleep is low voltage mixed frequency but what will frequently appear and is not an arousal?
Alpha bursts
Is a K complex or sleep spindles necessary to score an epoch as N2?
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
Describe a K complex
- 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
Rule for K complex associated arousal
Must commence no more than 1 second after the end of the K complex
EEG criteria for vertex waves
- Sharply contoured negative deflection (upward on EEG)
- Most often in central leads
- Usually seen in N1 sleep
EEG criteria for a slow wave
- At least 75 microVolt peak to peak amplitude
- 0.5 to 2 Hz (subset of delta: 1 - 4 Hz)
- Defining characteristic of N3 sleep
What are the sensors needed to detect:
- Apnea
- Hypopnea
Apnea = Oronasal thermal sensor (thermistor or thermocouple)
Hypopnea = Nasal pressure transducer (more sensitive than a thermal sensor)
What are the AASM criteria for scoring an apnea?
- 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
What are the AASM rules for scoring a hypopnea? Rules 1A and 1B
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
What is normal REM latency?
90 - 120 minutes
What has to happen to end N2 sleep?
- Arousal
- Wakefulness
- Transition to N3
- Transition to REM
- Major body movement
What are the rules for scoring REM sleep?
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
What are the rules for scoring REM sleep in the proceeding and following segments without Rapid Eye Movements?
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
Are sleep spindles seen in N3 sleep?
Yes. They can continue into N3 sleep.
Are eye movements seen in N3 sleep?
Usually, no
Criteria for N3 sleep
> 20% delta
What can be used to detect hypoventilation during a PSG?
- PcO2 in ABG
- PcO2 via end-tidal CO2 sensor
- PcO2 via transcutaneous CO2 sensor
What are the definitions of sinus tachycardia and sinus bradycardia in sleep?
Sinus tachycardia: > 90 bpm
Sinus bradycardia: < 40 bpm
(Note: This is different than during wake: 100 and 60)
What are the 2 different sensors on PSG for hypopnea and apnea respectively?
Pressure or PTAF = Pressure transducer for hypopnea
Flow or Airflow = Thermistor for apnea
What is the rule for a Major Body Movement with alpha?
If alpha is present for any part of an epoch with a MBM then it is scored as state Wake
What is the rule for an epoch with a Major Body Movement without alpha?
The epoch is scored the same stage as the epoch that follows it
