Friday, February 26, 2010

Defined: D


Delta rhythm: An EEG rhythm consisting of 1-4 Hz activity.

Dominant posterior rhythm: An EEG pattern with frequency appropriate to age which is observed over the occipital regions during relaxed wakefulness with eyes closed and attenuates with eye opening or attention.

Dypnagogic hypersynchrony: An EEG pattern consisting of paroxysmal runs or bursts of diffuse high amplitude sinusoidal 75 to 350 u V 3-4.5 Hz waves which begin abruptly, are usually widely distributed but often maximal over the central, frontal, or frontocentral scalp regions.

Thursday, February 25, 2010

Defined: C

Chheyne Strokes breathing: A breathing rhythm with a specified crescendo and decrescendo change in breathing amplitude.

Consensus: A specified agreement of appropriateness amongst a minimum of 7 individuals using RAND/UCLA methods.

Wednesday, February 24, 2010

Defined: B

Beta rhythm: An EEG rhythm consisting of 13-30 Hz activity.

Bradycardia: A sustained heart rate less than 40 beats per minute.

Bruxism: Grinding or clenching of the teeth during sleep that is often associated arousal.

Tuesday, February 23, 2010

Defined: A

Apnea:
An interruption of airflow lasting at least 10 seconds in adults or the equivalent of 2 breaths in children.

Alpha rhythm:
An EEG pattern consisting of trains of sinusoidal 8-13 Hz activity recorded over the occipital region with eye closure and attenuating with eye opening.

Asystole:
An interruption of cardiac rhythm lasting more than 3 seconds.

Atrial fibrillation:
An irregularly irregular ventricular rhythm associated with replacement of consistent P waves by rapid electrical oscillations.

Saturday, February 20, 2010

Follow Along My Last Semester and Beyond!

Last summer when I threw myself rather recklessly into a 9 month certificate course in Polysomnography I thought, 'maybe I should start a blog'.

My saner self resisted, not only would I be in the middle of school and work but I was juggling two or so non-related blogs.  Now, with one semester left and my other blogs lucky if I visit on a weekly basis I'm starting this one!

I'll share research, links, what to expect and events that relate to sleep medicine.  Plus, I'll be asking many questions so don't hesitate to chime in!

Monday, February 1, 2010

Glossary

Terms you may find useful.  More added often.

A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U V  W  X  Y  Z 

A

Apnea:
An interruption of airflow lasting at least 10 seconds in adults or the equivalent of 2 breaths in children.

Alpha rhythm:
An EEG pattern consisting of trains of sinusoidal 8-13 Hz activity recorded over the occipital region with eye closure and attenuating with eye opening.

Asystole:

An interruption of cardiac rhythm lasting more than 3 seconds.

Atrial fibrillation:
An irregularly irregular ventricular rhythm associated with replacement of consistent P waves by rapid electrical oscillations.

B

Beta rhythm:
An EEG rhythm consisting of 13-30 Hz activity.

Bradycardia:
A sustained heart rate less than 40 beats per minute.

Bruxism:
Grinding or clenching of the teeth during sleep that is often associated arousal.

C

Cheyne-Stokes breathing:
A breathing rhythm with a specified crescendo and decrescendo change in breathing amplitude.

Consensus:
A specified agreement of appropriateness amongst a minimum of 7 individuals using RAND/UCLA methods.

D

Delta rhythm:
An EEG rhythm consisting of 1-4 Hz activity.

Dominant posterior rhythm:
An EEG pattern with frequency appropriate to age which is observed over the occipital regions during relaxed wakefulness with eyes closed and attenuates with eye opening or attention.

Dypnagogic hypersynchrony:
An EEG pattern consisting of paroxysmal runs or bursts of diffuse high amplitude sinusoidal 75 to 350 u V 3-4.5 Hz waves which begin abruptly, are usually widely distributed but often maximal over the central, frontal, or frontocentral scalp regions.

E

Excessive fragmentary myoclonus:
Limb EMG activity of a specified frequency and duration often unassociated with visible movement; not a defined disorder.

Eye blinks:
EOG events consisting of conjugate vertical eye movements at a frequency of 0.5-2 Hz present in wakefulness with the eyes open or closed.

F

G

Guideline:
A recommendation based on level 2 evidence or a consensus of level 3 evidence.

H
Hypanagogic foot tremor:
Trains of EMG activity of the lower limb with a specified frequency,; not a defined disorder.

Hypopnea:
A specified reduction in airflow lasting at least 10 seconds in adults or the equivalent of 2 breaths in children.

I
J

K

K complex:
An EEG event consisting of a well delineated negative sharp wave immediately followed by a positive component standing out from the background EEG with total duration >0.5 seconds, usually maximal in amplitude over the frontal regions.

Low amplitude, mixed frequency activity:
An EEG pattern consisting of low amplitude, predominantly 4-7 Hz activity.

Low chin EMG tone: Baseline EMG activity in the chin derivation no higher than in any other sleep stage and usually at the lowest level of the entire recording.

L

Formulas

Looking for a formula to determine your patient's AHI?  Or want to figure out Total Sleep Time?  Over the next few weeks I'll be added these and many more formulas to the site and then compiling them all here.  These formulas are found in Fundamentals of Sleep Technology.


% of movement time
Minutes of MT / SPT (or TRT) x 100
Calculates minutes of movement time divided by sleep period time or total recording time and multiplying by 100 to get the total percentage.

% of Stage 1
Minutes of S1 / TST (or TRT or SPT) x 100
Calculates minutes in Stage 1 sleep by dividing by total sleep time or total recording time or sleep period time and multiplying by 100.

% of Stage 2
Minutes of S2 / TST (or TRT or SPT) x 100
Calculates minutes in Stage 2 sleep by dividing by total sleep time or total recording time or sleep period time and multiplying by 100.

% of Stage 3
Minutes of S3 / TST (or TRT or SPT) x 100
Calculates minutes in Stage 3 sleep by dividing by total sleep time or total recording time or sleep period time and multiplying by 100.

% of Stage REM
Minutes of REM / TST (or TRT or SPT) x 100
Calculates minutes in Stage REM sleep by dividing by total sleep time or total recording time or sleep period time and multiplying by 100.