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LA Times Health - The Unreal World - Awake
LA Times Health - The Unreal World - Awake
By Dr. Marc Siegel
December 3, 2007
Under but not completely out during surgery
In 'Awake,' a patient under anesthetic is fully aware. Medical experts say
it's possible but unlikely.
"Awake," Weinstein Co., GreeneStreet Films, filmed at New York's Bellevue
Hospital Center, release date Nov. 30.
The premise: Business mogul Clayton Beresford Jr. (Hayden Christensen) had a
massive heart attack and was treated at the local city hospital by
cardiovascular surgeon Jack Harper (Terrence Howard). As Beresford's heart
continues to weaken, he chooses Harper to perform his heart transplant.
But Harper and Beresford's fiancée and then wife, Samantha Lockwood (Jessica
Alba), are plotting to kill him -- and they intentionally choose an
anesthesiologist with a drinking problem, Dr. Larry Lupin (Christopher
McDonald), to deliver anesthetic during Beresford's surgery.
Beresford receives intravenous as well as mask anesthesia, but he never goes
to sleep. Although his muscles are paralyzed, he continues to experience
terrible pain and full awareness throughout the operation, as well as
hallucinations and out-of-body experiences. He wishes he could scream for
help.
In one scene, he experiences himself rising up from the operating room table
and pulling out all his lines and tubes -- only to discover, a moment later,
that he never really moved.
According to the film, 30,000 people experience so-called anesthesia
awareness every year in the U.S., out of 21 million cases of general
anesthesia.
Medical questions: Is anesthesia awareness as common as the film suggests?
Is it believable that someone experiencing it could be awake from beginning
to end of an operation? Are there signs of such awareness that an astute
anesthesiologist would recognize and counter during the course of an
operation? How common are out-of-body experiences during anesthesia
awareness?
The reality: Nineteenth century French physiologist Claude Bernard famously
described awareness after muscular paralysis (induced by administering the
drug curare) as finding oneself "fully alive, entombed in a corpse." Of
course, awareness might be expected in Bernard's days when patients received
only paralytics, but it is hardly supposed to happen today when we render
patients fully unconscious.
According to Peter Sebel, vice chairman of anesthesiology at Emory
University in Atlanta and author of a definitive study on the subject
published in 2004 in the journal Anesthesia & Analgesia, the film is correct
about how common the condition of anesthesia awareness is -- it occurs in
about 0.14% of cases.
But Dr. Johnathan Pregler, professor of anesthesiology at UCLA and director
of the UCLA Surgery Center, says this figure includes "any kind of
recollection," and that fully awake patients experiencing pain are by far
the exception rather than the rule.
Both experts say they've never heard of a case of continuous recollection
from before the induction of anesthesia until the end of the operation.
"That just doesn't happen," Sebel says.
General anesthesia usually involves premedication with a sedative such as
Versed, then induction of sleep with a medication called Propofol, followed
by an inhaled anesthetic. All of these chemicals cause amnesia, but not to
the same degree in all patients.
Because the drugs may suppress functioning of the heart, they are sometimes
used in lower doses during cardiac surgery, thereby increasing the risk of
anesthesia awareness.
Those undergoing heart surgery (or any procedure in which the surgeon needs
access to body cavities or needs the patient to be absolutely still, such as
for microsurgery) are also given drugs to paralyze their muscles.
Dr. Jeffrey Lee, director of obstetric anesthesia at Los Angeles County-USC
Medical Center, says that liberal doses of neuromuscular paralytics such as
rocuronium relax the muscles during the process of opening the chest and
working on the heart. In other words, waking up in the operating room unable
to move or speak is possible.
Still, in contrast to the movie's rendition, Sebel says that in the real
world experiencing pain is very unusual during cardiac surgery because of
the relatively high doses of opiates -- morphine or fentanyl -- that the
patient also receives.
In researching cases for his 2004 review, Sebel was struck by the lack of
changes in heart rate or blood pressure of patients who were aware -- so if
a patient does wake up, it may not be easy to spot.
Recognition should be easier when a patient is also in pain, Pregler says,
because there are usually changes in vital signs (such as increased heart
rate and blood pressure as well as sweating, pupil dilation and
tear-formation) that would be noticed by any competent anesthesiologist.
(These may be missed by the film's Dr. Lupin because he is intoxicated
during the surgery.)
Out-of-body experiences are unlikely with today's anesthetics, but there is
a 6% rate of dreaming during anesthesia, Sebel says.
Recent studies have shown that anesthesia awareness can be reduced by 80% in
high-risk patients -- those undergoing cardiac, obstetric or major trauma
surgeries -- through the use of electroencephalography (EEG) to monitor
brain activity during surgery: If EEG readings show that a patient is waking
up, he or she can be given more anesthetic. These brain monitors are present
in 60% of U.S. operating rooms.
Sebel is concerned that the movie will create unnecessary panic, and he
stresses again that anesthesia awareness is comparatively rare and
anesthesia is generally safe.
"People should not be frightened about having an anesthetic," he says. "It
is probably much safer than driving on an L.A. freeway."
Dr. Marc Siegel is an internist and an associate professor of medicine at
New York University's School of Medicine. He is also the author of "False
Alarm: The Truth About the Epidemic of Fear." In The Unreal World, he
explains the medical facts behind the media fiction. He can be reached at
marc@doctorsiegel.com.
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