For Poly Test 1 Flashcards
What are the modified EEG derivations?
F4-M1 C4-M1 O2-M1 Back up electrodes are F3-M2 C3-M2 O1-M2
What are the recommended EOG derivations and electrode positions?
E1-M2
E2-M2
Another acceptable EOG derivations and electrode position is
E1-Fpz and E2-Fpz
What are the recommended positions of the EOG?
E1 is placed 1cm below the left lower outer canthus
E2 is placed 1cm above the right upper outer canthus
What are the recommended EMG placement of the Chin?
Midline 1 cm above the inferior edge of the mandible
2 cm below and to the right of the the inferior edge of the mandible
2 cm below and to the right of the the inferior edge of the mandible
With EOGs what does vertical and horizontal eye movement deflections show?
Vertical show In-Phase deflections
Horizontal shows out of phase deflections
Looking left the back of the retina is negative and the front of the cornea is postive so the postive portion you get a downward deflection & right eye you get a negative deflection
Rules for Obstructive Apnea
A drop of ≥90% from baseline along WITH Cessation of airflow for 10 seconds or more with Ab & Thoracic effort that is terminated by an arousal and/or desaturation but doesn’t need arousals or desaturation to be an apnea.
Rules of Central Apnea
A drop of ≥90% from baseline along with Cessation of airflow for 10 seconds or more WITHOUT Ab & Thoracic Effort that is terminated by an arousal and/or or desaturation. With central apnea you have Chemoreceptor irregularities seen in patients with stroke or neurologic disorder
Rules of Mixed Apnea
A drop of ≥90% from baseline along with Cessation of airflow ≥ 10s (in Adults) with respiratory effort. There is a absent inspiratory effort in the initial portion followed by resumption in inspiratory effort in second portion of event
Rules of Hypopnea
The peak signal drops by 30% or MORE in THE nasal pressure or PAP flow (titration study) that last 10 seconds or more with either a (1A) ≥3% or (1B) ≥ 4% oxygen desaturation from baseline or the event is associated with an arousal. (1B doesn’t have arousal)
Rules of RERA (Respiratory Effort Related Arousal)
A sequence of breaths lasting ≥ 10 seconds with an increase in respiratory effort or by flattening of the inspiratory portion of the nasal pressure or PAP device flow waveform leading to arousal from sleep
Rules of Upper Airway Resistance Syndrome - UARS
Typically greater then 10 arousals/hour, normally no oxygen desaturations. Muscles of the upper airway relax and cause airway narrowing. Results in RERAs NOT apena or hypopnea. Results in an arousal secondary to increased work of breathing, measured in most labs by nasal pressure transducer. Gold Standard is esophageal balloon. UARS = RERAs
Determination of Arousals - Criteria
Abrupt shift in EEG frequency for greater then 3 seconds. Must have 10 seconds of intervening sleep before calling the EEG event. In REM must include simultaneous increase in chin EMG (EMG increase must be greater 1 second).
Score Cheyne-Stokes Breathing if both rules are met
a. An episodes of 3 or more consecutive central apneas and/or central hypopneas separated by a crescendo and decrescendo change in breathing amplitude with a cycle length of 40 or more seconds.
b. There are ≥5 central apneas and/or central hypopneas per hour of sleep associated with the crescendo/decrescendo breathing pattern recorded over ≥2 hours of monitoring.
When would you score stage W?
When 50 % or more of the epoch has alpha rhythm over the occipital region.
How would you score stage W without visually noticeable alpha rhythm?
With out Alpha you look for:
Eyes blinking at a frequency of 0.5 - 2 Hz
Reading eye movements
Irregular, Conjugate (same) rapid eye movement associated with normal or high chin muscle tone.
What happens if the patient is disconnected from the recording equipment? Score as stage W (Brief episodes of sleep during this time, if they occur, are not considered significant for the stage scoring summary)
What is the Frequency for BATD?
Beta = 13 Hz and up Alpha = 8 to 13 Hz Theta = 4 to 7 Hz Delta = Less than 4 Hz
What is the Frequency and amplitude of Delta (N3) slow wave activity?
Frequency is 0.5-2 Hz
Peak to peak amplitude of greater than 75 uv
Measured in the frontal EEG
Voltage / Sensitivity = What
the signal Deflection (mm)
What stage has a Frequency of greater than 13 cps. Has a wave compressed at 10 mm/s, low amplitude, mixed frequency when awake with eyes open.
Beta Activity
What stage has a frequency of 8 to 13. Is Maximal in occipital leads (O1,O2), with eyes closed. Has a variable amplitude and attenuates (reduces) with eyes open.
Alpha Activity.
When to score Stage W?
Score epochs as stage W when greater than 50 % of the epoch has alpha rhythm over the occipital region.
For any epochs without visual alpha rhythm score stage W if any of the following is present:
- Eye blinks at a frequency of 0.5-2 hz
- Reading eye movements
- Irregular conjugate (same) rapid eye movements associated with high or normal chin EMG
What are the 4 eye movements seen in stage W of sleep recording?
Eye Blinks
Reading eye movements
Rapid eye movements
Slow eye movements
When to score Stage N1.
EEG has Less than 50% is alpha activity
Low amplitude, mixed frequency (LAMF) predominantly 4-7 hz
May have vertex sharp waves
No K complex or spindles ( in 1st half of epoch)
EOG shows slow eye movements (SEM’s)
The EMG is variable, and may decrease from wake. Snore artifacts may occur in the EMG
What is a characteristic of N1 sleep?
Vertex sharp waves with a duration of less than < 0.5 sec.
Maximal seen over the central region and distinguished from backround activity
When does Stage N1 begin?
When you see any of the following.
The activity is 4 -7 Hz
You see vertex sharp waves or slow eye movements.
What is the Frequency range for theta (N1) activity?
4 - 7 Hz
What are some common characteristics of N2?
Spindles that are seen in the central region.
K complexs that are not associated with an arousal and are seen in the frontal region
What does Benzodiazepine hypnotics increase?
The density or number of sleep spindles seen in a given time period.
What is the minimum lifespan of a sleep spindle?
.5 seconds form 2 to 4 a cycles in adults and 6 to 7 cycles in young
What is a characteristics of K- complexes?
It has a negative sharp wave followed by a positive deflection
the duration is at least 0.5 seconds
There is no specific amplitude criteria
K complexs are seen maximally in the frontal EEG.
When do you begin scoring N2?
When 1 or both of the following occur during the first half of that epoch or the last half of the previous epoch.
One or more K complex that is not associated with an arousal and there is more than one spindle.
What could end stage N2?
An arousal or transition to stage W
Where are K complexes seen Maximally?
K complexs are seen maximally in the frontal EEG.
What are the Rules for major body movements?
Stage W if alpha is present for part of the epoch.
It’s still Stage W if no alpha is present and the epoch either precedes or follows the epoch with movement
Otherwise, score the epoch as the same stage as the epoch that follows it.
When would you score as a major body movement?
When movement and muscle artifacts obscure the EEG for more than Half (15 sec) of an epoch to the extent that the sleep stage cannot be determined.
According to the AASM Scoring Manual, what is the frequency range for eye blinks?
0.5 - 2 Hz
According to the AASM Scorning Manual, what is the duration of a vertex wave in N1?
<0.5 (Half second or less)
For Patients who do not generate alpha rhythm, what may begin Stage N1?
Onset of slow eye movements
The AASM Scoring Manual notes that K complexes are usually Maximal in amplitude when recorded from which of the following derivations?
F4 - M1
If an Epoch contains a Major body movement and alpha rhythm, what is the sleep stage of that epoch?
Stage W
What does bruism look like? Hint: look at the Chin EMG
a. Bruxism may consist of brief (phasic) or sustained (tonic) elevations of chin EMG activity that are at least twice the amplitude of background EMG.
b. Brief elevations of chin EMG activity are scored as bruxism if they are 0.25-2 seconds in duration and if at least 3 such elevations occur in a regular sequence.
c. Sustained elevations of chin EMG activity are scored as bruxism if the duration is more than 2 seconds.
d. A period of at least 3 seconds of stable background chin EMG must occur before a new episode of bruxism can be scored.
e. Bruxism can be scored reliably by audio in combination with polysomnography by a minimum of 2 audible tooth grinding episodes/night of polysomnography in the absence of epilepsy.
What is the sensitivity, L/H filter and sampling rate for The EEG and EOG channels?
Sensitivity 5-7 Uv/mm LFF/HFF 0.3-35 Hz Sampling rate 200 - 500 Hz
What is the sensitivity, L/H filter and sampling rate for The EMG and snoring sound channels?
Sensitivity 10 Uv/mm LFF/HFF 10-100 Hz Sampling rate 200 - 500 Hz Note: the snoring channel has no sensitivity
What is the sensitivity, L/H filter and sampling rate for The EKG channels?
Sensitivity 20 Uv/mm LFF/HFF 0.3-70 Hz Sampling rate 200 - 500 Hz
What is the sensitivity, L/H filter and sampling rate for The Respiratory channels?
(Airflow, Nasal Pressure, Rib cage movements) No Sensitivity LFF/HFF 0.1-15 Hz Sampling rate 25 - 100 Hz
What is the sensitivity, L/H filter and sampling rate for Oximetery?
No Sensitivity, No LFF/HFF, Sampling rate 10 - 25 Hz
What is the sensitivity, L/H filter and sampling rate for Esophageal Pressure?
No Sensitivity, No LFF/HFF, Sampling rate 25 - 100 Hz
What is the sensitivity, L/H filter and sampling rate for The body position?
No Sensitivity, No LFF/HFF, Sampling rate 1 - 1 Hz
What is the placement of the chin electrodes?
One electrode in the midline 1cm above the inferior edge of the mandible; below 2cm to the right of the midline; below 2cm to the left of the midline.
What are the criteria for stage W?
Alpha rhythm in the occipital regions; conjugate (same) vertical eye movements of 0.5 - 2Hz; trains of conjugate (same) eye movements consisting of a slow phase followed by a rapid phase in the opposite direction; rapid eye movements; and normal or high chin EMG
What are the rules for scoring stage W?
More than 50% of the epoch has alpha rhythm over the occipital region If Stage W doesn’t have alpha then look for a) eye blinks of 0.5 - 2 Hz b) reading eye movements; c) irregular conjugate rapid eye movements associated with normal or high chin muscle tone
What are the criteria for scoring a stage as N1?
Slow eye movements that are reasonably regular and have an initial deflection usually lasting >500 msec; low amplitude, mixed frequency (4-7 Hz) activity; vertex sharp waves; and sleep onset
What are the criteria for scoring a stage as N2?
If one or both happen during the first half of the epoch or the last half of the previous epoch. a) one or more k complexes unassociated with arousals b) one or more trains of sleep spindles
What are the criteria for scoring stage N3?
20% or more of epoch consists of slow wave activity (0.5 - 2 Hz with peak to peak amplitude of >75 uV measured over the frontal regions mirrored in the EOGs)
What is a vertex sharp wave?
Sharply contoured waves with a duration of <0.5 seconds maximal over the central regions and distinguishable from the background activity.
What is the criteria for scoring stage N1?
Attenuated (reduced) alpha rhythm replaced by low amplitude mixed frequency activity for more that 50% of epoch
How is sleep latency different in those that do not generate alpha rhythm?
Shorter than normal
What are the scoring criteria for stage R sleep?
a) low amplitude, mixed frequency EEG; b) low chin EMG tone; c) rapid eye movements
What are the rules for stage N1 in patients that do not generate alpha?
4-7 Hz activity with slowing background frequencies by at least 1 Hz from Wake, vertex sharp waves and slow eye movements
What kind of eye movements are typical in N3 sleep?
Eye movements are not typically seen during stage N3 sleep
What are some characteristics of stage R sleep?
Rapid eye movements, low chin EMG tone; Sawtooth waves 2-6 Hz over central regions, often preceding a burst of rapid eye movements; transient (short time) muscle activity
What is the rule that defines the continuation of stage N2 sleep?
Continue to score epochs with low amplitude, mixed frequency EEG activity without K complexes or sleep spindles as stage N2 if they are preceded (come before) by a) K complexes unassociated with arousals or b) sleep spindles
What criteria define the end of a period of stage N2 sleep?
End stage N2 sleep when 1 of the following occur: a) transition to stage W; b) an arousal changes it to stage N1 until a K complex unassociated with an arousal or a sleep spindle occurs; c) a major body movement followed by slow eye movements and low amplitude mixed frequency EEG without nonarousal associated K complexes or sleep spindles; d) transition to stage N3; e) transition to stage R.