Heart Association Warns of Surgery Risks in Obese

MONDAY, June 15 (HealthDay News) -- Severely obese people undergoing surgery are at greater risk of heart problems, wound infections, prolonged hospital stays and other complications, according to a Scientific Advisory from the American Heart Association.

Yet many cardiologists, surgeons, anesthesiologists and other health-care providers underestimate the seriousness of the risks, particularly to the heart, the association warns.

About 3 to 4 percent of Americans are considered severely obese, defined as having a body mass index of 40 or higher, according to information in a news release from the association.

People who are severely obese are more likely to have underlying conditions that raise the likelihood of surgical complications. These conditions include heart failure, narrowed arteries (known as atherosclerosis), high blood pressure, heart rhythm disorders, a history of blood clots, poor cardiorespiratory fitness, pulmonary hypertension and sleep apnea, the association added.

Before surgery on someone who's severely obese, health-care providers need to do a thorough examination, taking into account the person's age, gender, fitness level, electrolyte disorders and heart failure, each of which is an independent predictor of how well a person will fare during and after surgery, the advisory states.

Pre-surgical examinations that might be called for include electrocardiograms, chest X-rays and other non-invasive evaluations, such as exercise testing.

Even with the additional tests, obesity can make it more difficult to discern which symptoms are caused by an underlying illness and which are caused by the obesity itself, explained Dr. Paul Poirier, lead author of the advisory and director of the cardiac prevention/rehabilitation program at Laval Hospital in Quebec, Canada.

"A severely obese patient can be technically difficult to evaluate prior to surgery," Poirier said in the news release. "For example, severely obese people might feel chest tightness that could be a symptom of their obesity or of an underlying cardiac problem. Doctors need to carefully evaluate severely obese patients before they have surgery."

The advisory, which was issued June 15, also recommends that people who are severely obese work toward making lifestyle changes that will improve their health before having any sort of surgery.

"Since recovery can be a problem for these patients, we recommend that they take steps to be as healthy as possible before going into surgery," Poirier said. "For example, the person with diabetes should get his or her blood sugar under control."

The advisory includes a proposed scoring tool to determine the risk of undergoing weight-loss surgery and calls for other risk-assessment tools for other surgeries.

Despite the challenges, people who are severely obese are not at higher risk of death during surgery, a misconception among some health-care professionals, according to the advisory.

"Some surgeons are under the impression that severely obese patients are more likely to die in surgery than people who are not obese, and won't operate on them as a result," Poirier said. "This is not true. Severely obese patients are at increased risk for pulmonary embolism, wound infection and other conditions. But they are not more likely than their lower-weight counterparts to die as a result of surgery."

More information

The American Heart Association has more on obesity.