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DURHAM, N.C. – In the first such clinical trial of its kind,
researchers at Duke University Medical Center have found that
acupuncture is more effective at reducing nausea and vomiting
after major breast surgery than the leading medication.

The researchers also found that patients who underwent the
5,000-year-old Chinese practice reported decreased
postoperative pain and increased satisfaction with their
postoperative recovery. In conducting the trial, the
researchers also demonstrated that the pressure point they
stimulated possesses previously unknown pain-killing
properties.

Results of the Duke study were published Sept. 22, 2004, in
the journal Anesthesia and Analgesia.

Treating postoperative nausea and vomiting (PONV) is an
important medical issue. About 70 percent of women who undergo
major breast surgery requiring general anesthesia suffer from
this complication, according to Duke anesthesiologist Tong Joo
(T.J.) Gan, M.D., who led the trial. These adverse side effects
are important factors in determining how soon patients can
return home after surgery.

"The patients in our randomized trial who received
acupuncture enjoyed a more comfortable recovery from their
surgery than those who received an antisickness medication,"
Gan said. "In the areas of PONV control, pain relief, and
general overall satisfaction, acupuncture appears to be more
effective than the most commonly used medication, with few to
no side effects."

In the trial, Gan employed an electro-acupuncture device in
which an electrode – like that used in standard EKG tests – is
attached at the appropriate point. In this case, the point is
known as P6 and is located below the wrist. Instead of actually
breaking the skin with the traditional long slender needles,
the electro-acupuncture device delivers a small electrical
pulse through the skin.

"Electro-acupuncture enhances or heightens the effects of
traditional acupuncture," Gan explained. "Also, in the busy and
complicated setting of the operating room, the
electro-acupuncture device is much more convenient to use."

The researchers enrolled 75 women who were to undergo major
breast surgery (breast augmentation, breast reduction or
mastectomy) requiring the use of general anesthesia. They were
then randomized into three groups: one which received
acupuncture, one which received the medication ondansetron
(trade name Zofran), and a group that received neither.

The surgeries lasted anywhere from two to four hours, and
the incidence of PONV and pain were tracked at 30-minute
intervals for the first two hours after surgery, and then again
24 hours later.

Two hours after surgery, 77 percent of the patients
receiving acupuncture experienced no PONV, nor did they require
an antiemetic drug to reduce nausea and vomiting, compared to
64 percent for those who received ondansetron and 42 percent
who received nothing. At 24 hours, the rates were 73 percent,
52 percent and 38 percent, respectively.

"When used for the prevention of PONV, electro-acupuncture
stimulation or ondansetron was more effective than placebo with
a greater degree of patient satisfaction, but the
electro-acupuncture appears to be more effective in controlling
nausea, compared to ondansetron," Gan said.

The electro-acupuncture was applied at the 6th point (P6)
along the pericardial meridian, which is located two inches
below the bottom of the palm of the hand and between the two
tendons connecting the lower arm with wrist. According to
Chinese healing practices, there are about 360 specific points
along 14 different lines, or meridians, that course throughout
the body just under the skin.

"The Chinese believe that our vital energy, known as chi,
courses throughout the body along these meridians," Gan
explained. "While healthiness is a state where the chi is in
balance, unhealthiness arises from either too much or too
little chi, or a blockage in the flow of the chi. By applying
acupuncture to certain well-known points, the Chinese believe
they can bring the chi back into balance."

While pressure on other acupuncture points – LI4 on the
hand, SP6 on the leg and "back-shu" along the spine – are known
to have pain-killing effects, this is the first to show that P6
also has analgesic effects to go along with its known
antiemetic properties, Gan said.

While it is not completely known why or how acupuncture –
whether electro-acupuncture or traditional – works, recent
research seems to point its ability to stimulate the release of
hormones or the body's own painkillers, known as endorphins,
Gan said.

Interestingly, Gan said, low-frequency modulation of the
electro-acupuncture device appears to release one type of
endorphin that produces analgesia of slower onset but longer
duration. When higher frequencies are used, the body appears to
produce another type of endorphin that provides rapid
analgesia, but of shorter duration.

The scientists will conduct further studies comparing the
various combinations of these frequencies, as well as comparing
the combination of acupuncture with other antiemetic
medications.

Gan said that women in general are three times more likely
to suffer from PONV after major surgery than men, though the
reasons why are not known.

The research was supported by Duke's Department of
Anesthesiology. Members of Gan's team were, all from Duke: Kui
Ran Jiao, M.D., Michael Zenn, M.D., and Gregory Georgiade,
M.D.