Study probes nausea after surgery

One-third of patients undergoing surgery will experience postoperative nausea and vomiting, often resulting in discomfort and longer hospital stays. According to a study published earlier this month by Dr. T. J. Gan, an associate professor of anesthesiology, increased physician-patient interaction greatly reduces the risk of these side effects.

Although researchers have not yet identified the mechanism that causes postoperative nausea and vomiting, there are definite risk factors associated with the condition. For example, women are three times more likely to experience PONV than men, and younger patients tend to experience it more frequently than older ones. Other risk factors include a previous history of nausea and vomiting or of motion sickness. Non-smokers are also more likely to experience PONV.

"Clinicians and anesthesiologists need to ask their patients whether they are at a high risk, or identify the factors associated with high risk for nausea and vomiting," Gan said.

Gan's study demonstrated that once patients are identified as high-risk, appropriate preventative measures can greatly reduce the likelihood of PONV. For example, the use of acupuncture during major breast surgeries reduces the risk of PONV to only 20 percent, and the use of acupuncture in conjunction with a combination of anti-emetics can lower the rate to below 10 percent.

Other effective deterrents include giving patients additional oxygen and sufficient fluids during surgery. Hypnosis has also been shown to reduce the rate of PONV.

"Learning to ask the right questions can improve outcome and improve patient care," said Dr. Anthony Kovac, professor of anesthesiology at the University of Kansas Medical Center. "Perhaps a thing that you might think is common sense and intuitive is something we really haven't looked at," he said.

Dr. John Leslie, professor of anesthesiology at the Mayo Clinic, agreed.

"We're good at treating pain, and this is the next step in making the whole experience safe, comfortable and pleasant. I think the paper really does alert people to the fact that there is a large body of literature available to help them determine who is at risk as well as select the appropriate treatments," he said.