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Q: sleep apnea - BiPap ST ( Answered,   1 Comment )
Subject: sleep apnea - BiPap ST
Category: Health
Asked by: thurber-ga
List Price: $10.00
Posted: 06 Jul 2006 18:51 PDT
Expires: 05 Aug 2006 18:51 PDT
Question ID: 743951
Does BiPap ST really offer an advantage to sleep apnea patient with or
without underlying lung disease even with documented central apneas? 
Subject: Re: sleep apnea - BiPap ST
Answered By: crabcakes-ga on 06 Jul 2006 19:52 PDT
Hello Thurber,

   Yes, a BiPAP can be a great lifesaving device. In fact most sleep
apnea patients have no pulmonary problems. Studies have shown however,
that CPAP or BiPAP can be easier on patients with respiratory diseases
than mechanical ventilators. (More below)

Most sleep apnea is caused the soft tissue in the back of the throat,
which does not allow one to take in a good breath. The most common
symptom is feeling very sleepy during the day, snoring, trouble
concentrating, among others

?Untreated, sleep apnea can be life threatening.  Excessive daytime
sleepiness can cause people to fall asleep at inappropriate times,
such as while driving.  Sleep apnea also appears to put individuals at
risk for stroke and transient ischemic attacks (TIAs, also known as
?mini-strokes?), and is associated with coronary heart disease, heart
failure, irregular heartbeat, heart attack, and high blood pressure. 
Although there is no cure for sleep apnea, recent studies show that
successful treatment can reduce the risk of heart and blood pressure

   ?Apnea is Greek for "without breath,'' and those who suffer from it
can literally stop breathing for more than 10 seconds, sometimes
causing dozens of sleep disruptions each night. Obstructive sleep
apnea occurs when the tongue and soft tissues in the back of the
throat collapse to block the airway during sleep. The pauses in
breathing can occur a few times or several hundred times a night, and
the sleeper is typically unaware of it.

"When the body isn't getting the oxygen it needs, it kicks into
overdrive, sending a surge of adrenaline that makes the heart beat
faster and blood pressure rise sharply," said Dr. Robert McCain,
director of the Sleep Center at Southern Hills Medical Center.

Dr. McCain says such high blood pressure has long been associated with
heart attack and stroke. The rapid rise and fall of oxygen levels,
called intermittent hypoxia, causes inflammation, an underlying cause
of many problems including the clogging of coronary arteries.?

?"Treatment options for sleep apnea have steadily improved," said Dr.
McCain. "The most common treatment is a mask-like device called CPAP
('continuous positive airway pressure') that pushes pressurized air
down the airways to keep them open. Today's masks come in a variety of
styles designed to help patients sleep through the night."

Dr. McCain says a variety of other devices have been developed to keep
the airways open, and these have had some success alleviating mild to
moderate forms of sleep apnea. In milder cases, losing weight,
sleeping on one's side or abstaining from alcohol sometimes can offer
relief. In more severe cases and for people who can't stand wearing a
mask, surgery to remove tissue from the mouth or throat may be

   ?Most patients with sleep apnea can be successfully treated with
CPAP. In some cases, your doctor may prescribe BIPAP instead of CPAP
for obstructive sleep apnea. BIPAP, (pronounced ?BI-PAP?) is short for
bi-level positive airway pressure. The function of the BIPAP machine
is the same as CPAP; however, it provides two different levels of
pressure. There is a higher pressure provided when you are breathing
in. A lower pressure is provided when you are breathing out. This
mimics normal breathing and can be more comfortable for some people.?

   ?Obstructive sleep apnea syndrome (OSAS) is a serious, potentially
life-threatening condition that is far more common than generally
understood. First described in 1965, sleep apnea is a breathing
disorder characterized by brief interruptions of breathing during
sleep. It owes its name to a Greek word, apnea, meaning, "want of

There are two types of sleep apnea: central and obstructive. Central
sleep apnea, which is less common, occurs when the brain fails to send
the appropriate signals to the breathing muscles to initiate
respiration. Obstructive sleep apnea is far more common and occurs
when air cannot flow into or out of the person's nose or mouth even
though efforts to breathe continue.?
This site has some additional information and a nice illustration.

   ?BiPAP stands for Bilevel Positive Airway Pressure. Bilevel means
that the pressure varies during each breath cycle. When the user
inhales, the pressure is similar to CPAP. When they exhale, the
pressure drops, making it much easier to breath. Inhale, pressure
rises, exhale, pressure drops. These machines are commonly prescribed
for patients who have difficulty tolerating CPAP. They cost more, are
generally bigger but they do tend to be much more comfortable,
particularly for patients that have relatively high pressure

BiPAP is a registered trademark of Respironics, Inc. Other
manufacturers make VPAP and Bilevel machines that provide this same
basic feature.

Sometimes you will see a "ST" behind BiPAP, VPAP, or Bilevel. The ST
stands for Spontaneous Timed. This means that if the user does not
breath on their own, the machine will initiate a breath for them. This
feature is very useful in treating central sleep apnea and a host of
pulmonary disorders.?

Here are a few users? ratings:

   ?For acute respiratory failure however, compliance may be a
problem. The respiratory technologist should be prepared to stay with
the patient, while he/she gets used to the machine. It may be
necessary to try several masks to provide effective ventilation that
is comfortable for the patient. The patient must always be shown how
to remove it in case of panic or vomiting. If the patient has a
decreased level of consciousness, copious secretions, can not protect
his airway or is unstable hemodynamically, then intubation is
There are now multiple randomized, prospective studies showing the
benefit of non-invasive ventilation in respiratory failure.
Furthermore, not only has it been shown to be an effective therapy,
but there is also evidence that it contributes to less time in
hospital, fewer complications and decreased mortality compared to
immediate intubation and ventilation.4 One study showed that there is
a reduction of intubation from 74% to 16%, major complications were
decreased from 48% to 16% and length of stay from 35 days to 23 days.
Mortality was decreased from 29% to 9%.3 It should be noted that only
1/3 of the patients could be randomized and only between 50-80% of
patients are compliant with treatment. Still there is certainly Level
I evidence to support the use of BiPAP in patients with a pCO2>50, a
pH<7.35 and a RR>30.?

?Until further studies are done, it is recommended that CPAP be tried
first, and if BiPAP is attempted, it should be initiated cautiously,
watching for hypotension.

There is still controversy on how and why CPAP works in CHF. There is
no dispute that it reduces the work of breathing by improving
atelectasis and V/Q ratios. Some studies have suggested it also
improves preload and afterload and that there is actually an
improvement in cardiac index. Of even more interest, studies out of
Toronto by Bradley suggest that up to 50% of patients with CHF have
sleep apnea. In these patients, the use of CPAP not only improves
sleep, but leads to an improvement in ejection fraction that lasts
into the daytime hours when they are awake. It is postulated that CPAP
reduces preload and also afterload. It is possible that obstructive
sleep apneas can put a severe strain on the heart by markedly
increasing afterload and leading to hypertension.

In conclusion, for those patients who present to the emergency
department with acute respiratory failure but with normal levels of
consciousness, no major secretion problems and who are hemodynamically
stable, a trial of BiPAP or CPAP should be attempted prior to
considering intubation and a mechanical ventilator.?

   If your doctor has ordered a sleep study and decides you need a
BiPAP, I would certainly recommend that you use it. With a properly
fitted soft mask, and correct usage, you should find yourself feeling
better during the day, and perhaps avoid an adrenaline triggered heart
attack or stroke. Don?t give up, and allow yourself to get used to it.
The supplier should send a rep to your house to train you in how to
use it, and measure you for the right size mask.

Good luck!

Please ask for an Answer Clarification, if any part of this answer is
unclear, and allow me to respond, before you rate. I will be happy to
assist you further on this question, before you rate.

Sincerely, Crabcakes

Search Terms

BiPap and Sleep Apnea
Sleep Apnea
COPD or respiratory disease + BiPAP or CPAP
Subject: Re: sleep apnea - BiPap ST
From: myoarin-ga on 06 Jul 2006 19:07 PDT
duplicate question,  see 743951

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