University of Texas Medical Branch
Effective Date:
January 2013
Center For Sleep Disorders
Revised Date:
January 2014
Policy: 08.06.03 Biological Calibrations
Review Date:
January 2013
_______________________________________________________________________________________
Biological Calibrations
Audience:
Purpose:
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All personnel in the Sleep Disorder Center.
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To ascertain that the physiological recording of each signal is displayed correctly
on the polysomnogram.
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Policy:
Biological calibrations are exercises performed prior to initiating each study and
after each study to verify correct input derivations and signal quality. They are
important to facilitate scoring and interpretation.
Biological calibrations must be performed with the patient in the supine position,
the patient must be quiet and not talking, the patient must lie completely still and
the television, cell phone and other electrical devices (IPads, etc.) must be turned
off. Allow at least 5 seconds in between each set of instructions to allow each
biological calibration to be easily identifiable. Repeat each biological calibaration
until the patient performs the commands properly and the correct signal is
displayed. If the patient is following commands properly but there is still no
proper signal make corrections to the sensor until the proper signal is displayed.
Only then should biological calibrations be resumed. The study may be continued
once all signals have been verified.
Procedure:
If the patient is Spanish speaking only, biological calibrations must be attempted
in Spanish by using the English to Spanish translation outlined in this protocol.
Biological calibrations will be performed on children ages 5 and up. For patients
with cognitive impairment or hearing disability every effort should be made to
complete biological calibrations which may include coaching and acting out the
command in front of the patient.
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The following represent the correct stages of biological calibrations. Use either the
F-Keys on the keyboard or the X-Keys to time stamp your biological calibrations
on the recording.

F4
“Close your eyes and relax” – Verify alpha activity for 30 seconds.

F5
“Open your eyes” – Check for alpha attenuation for 30 seconds to
get a sample of wake EEG with eyes open.

F6
“Keeping your head still and moving your eyes only, look to the
left, now look to the right, look left, look right,” until 5 sets are
complete and verified then tell the patient to “look straight ahead”.
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Page 1 of 4
University of Texas Medical Branch
Effective Date:
January 2013
Center For Sleep Disorders
Revised Date:
January 2014
Policy: 08.06.03 Biological Calibrations
Review Date:
January 2013
_______________________________________________________________________________________
When eyes move right, both EOG channels move towards each
other (out of phase). When eyes move left, both EOG channels
move away from each other (out of phase).

F8
“Keeping your head still and moving your eyes only, look up, look
down, look up, look down,” until 5 sets are complete and verified
then tell the patient to “look straight ahead”. When eyes move up,
both EOG channels move towards each other (out of phase). When
eyes move down, both EOG channels move away from each other
(out of phase).

F10
“Slowly blink your eyes 5 times” and count aloud for the patient.
Blinks should show both EOG channels moving in phase up and
down.

F11
“Grit your teeth or pretend like you’re chewing” and verify
increase in chin EMG. The increase in chin EMG should last 5
seconds.

ShF7
“Make a snoring sound” and verify burst on snore EMG. Repeat 3
times. You should end up with 3 individual bursts in the snore
EMG.

F12
“With your right leg only, point and flex your toes up then down.
Relax.” Verify increase in leg EMG. Repeat the sequence 5 times
allowing 1-2 seconds between each sequence. You should end up
with 5 individual bursts in the right leg EMG.

ShF12 “With your left leg only, point and flex your toes up then down.
Relax.” Verify increase in leg EMG. Repeat the sequence 5 times
allowing 1-2 seconds between each sequence. You should end up
with 5 individual bursts in the left leg EMG.

ShF6
“Slowly take 3 deep breaths.” Verify on inspiration thermistor,
PTAF and both abdominal and chest effort channels rise and on
expiration fall.

ShF3
“Take a deep breath and hold it for 10 seconds.” Verify thermistor,
PTAF and both abdominal and chest effort channels will be flat.
**Each biological calibration should be verified. If it is not verified
it should be repeated until there is verification**
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Page 2 of 4
University of Texas Medical Branch
Effective Date:
January 2013
Center For Sleep Disorders
Revised Date:
January 2014
Policy: 08.06.03 Biological Calibrations
Review Date:
January 2013
_______________________________________________________________________________________
Procedure:
English to Spanish biological calibration translation:

Eyes closed – Sierre los ojos (After 30 seconds) Stop - Alto

Eyes open – Abra los ojos ( After 30 seconds) Stop - Alto

Without moving your head, look left, look right – Sin mover la cabeza,
mire a la izquierda, mire a la derecha cinco veces

Look up, look down – Mire para arriba, mire para abajo cinco veces

Blink 5 times – Abra y sierra los ojos cinco veces

Grind teeth – Rechine los dientes

Snore loudly – Ronque cuatro veces lo mas fuerte que pueda

Flex and point left foot – Flexión y apunte el pie izquierdo cinco veces

Flex and point right foot – Flexión y apunte el pie derecho cinco veces

Take 3 deep breaths – Tomar tres respiraciónes profundas grandes

Hold breath for 10 seconds – Pare de respirar por diez segundos
Thank you – Gracias
Good night – Buenas noches
One minute – Un minuto
Good morning – Buenos dias
Test is completed – Prueba es completada
Call your doctor for results – llame a su doctor por los resultados
You may leave – Puede dejar
Good bye - Adios
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Page 3 of 4
University of Texas Medical Branch
Effective Date:
January 2013
Center For Sleep Disorders
Revised Date:
January 2014
Policy: 08.06.03 Biological Calibrations
Review Date:
January 2013
_______________________________________________________________________________________
References:
Spriggs WH, Principles of Polysomnography. Sleep Ed., 2002.
American Academy of Sleep Medicine (AASM). Accreditation Reference Manual For Policies
and Procedures, Documentation and Reporting. May 2007. Web. June 2012.
GRASS Technologies, An Astro-Med Inc. Twin Recording and Analysis Software, Users
Manual. Version 4.3. 2008
Google. Google Translate. English to Spanish. Web. March 2012.
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Shahzad Jokhio, M.D.
Medical Director
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