What to expect
from Sleep
Studies
The all-night sleep study is frequently used by
sleep physicians
to evaluate
adult patients
while
they are
sleeping. This
laboratory test
is extremely
valuable for
diagnosing and
treating many
sleep disorders,
including
neurological
disorders,
movement
disorders and
nighttime
breathing
disorders.
All-night sleep
studies (also
called
polysomnography)
may be
ordered by
physicians and
performed in
a sleep
laboratory.
Patients come to
the laboratory
between 9 and
9:30 p.m. on the
appointed day.
There they meet
with a sleep
technologist,
who will explain
and perform the
study. The
sleeping rooms
are comfortable
rooms
with normal
beds. Each room
has its own
bathroom and
television.
Shower
facilities are
also available.
For studying the quality of sleep, electrodes are
applied to the
scalp, sides of
the head and
under the chin,
chest and leg.
This
will allow us to
measure
brain waves,
heart rate, and
eye movement. A
sensor is
also
placed by the
nose and mouth
to
measure airflow.
Belts are placed
around the rib
cage and abdomen
to measure
breathing
movements. A
clip is placed
on a finger for
measurement of
blood oxygen
levels. Other
measurements may
be done as
required.
No needles are
used and there
is no pain
associated with
he the sleep
study.
The electrodes
are connected to
a box by the
bedside for
relaying the
signals to a
central control
room. In
addition, all
patients are
videotaped while
asleep.
In the central control room, the technologist
monitors the
patient’s sleep
and general
condition. Any
problems with
the study may be
easily dealt
with. Patients
can
easily call the
technologist if
there is a
problem as well.
For some patients who have sleep apnea, the
effects of
continuous
positive airway
pressure (CPAP)
are evaluated.
Usually these
are patients who
have had a
previous sleep
study to
diagnose the
condition.
During the CPAP
study,
everything is
done as for a
diagnostic
study. In
addition, a mask
is fit around
the nose or
around the nose
and mouth.
During sleep, we
attempt to find
a pressure level
that holds the
airway open and
lets the patient
get a good
night’s sleep.
Patients generally get out from the study around
6:30 to 7 in the
morning.
However, if an
earlier wake-up
is needed, the
patient just
needs to let the
technologist
know.
Once the sleep study is completed, it is scored
by a scoring
technologist and
sent to a sleep
specialist for
interpretation.
This entire
process takes
7–10 days. The
interpretation
is sent to the
physician who
ordered the
sleep study and
appropriate
follow-up is
arranged.
Sleep studies are generally easy to tolerate,
comfortable for
patients, and
give the sleep
physician the
information
he/she needs to
accurately
diagnose and
treat the sleep
disorder.
