Discuss as:

Too fat for anesthesia? Suction cups hold up patients' guts during surgery

Jeff Fitlow / Rice University

A team of Rice University engineering seniors created a device to lift the weight from the abdomens of obese patients undergoing surgery. The R-Aides device uses suction cups hooked to a vacuum to help patients under light sedation breathe.

At first it sounds like the start of one of those offensive “fat” jokes obese people hate so much: “How fat was he? So fat the surgeons need suction cups to lift his belly.”

But this is no joke. A team of Rice University bioengineering students, responding to an urgent request from heart surgeon Mehdi Razavi, has developed a device that can lift the abdomen of an obese patient undergoing surgery so the patient can breathe.

Razavi, an electrophysiologist who specializes in implanting pacemakers and performs heart catheterizations, often places his patients under “conscious sedation,” a light anesthesia, because if the patient were simply knocked out, with a tube down his or her throat, and a machine doing the breathing, there’d be a greater risk of complications. But during one surgery on an obese man, Razavi realized his patient was snoring and having trouble breathing. The man’s oxygen levels were dropping.

That’s because the man was struggling against his own abdominal fat.

“It’s like putting a suitcase on the belly,” Razavi said. “It presses down and the belly has to go somewhere, so it pushes against the lungs, and if you try to take a deep breath, the lungs cannot expand.” The problem could become so severe, the doctor would have to stop the surgery.

The device the students designed uses suction cups hooked to a horizontal beam hovering above the abdomen. The cups are attached to the skin – there is a slight chance of bruising, student Marisa Prevost said – and a vacuum pump. Activating the device slightly raises the abdomen so the fat is out of the way.

When Razavi first approached the students for help, they were incredulous. “When we first heard about it, we were, like, ‘Huh? What?’” Prevost said. “We thought, that’s kind of weird.”

Now though, they’re intimately aware of how America’s obesity crisis is affecting medical practice in dozens of ways.

As of 2010, more than 35 percent of U.S. adults were obese. By 2030, the U.S. obesity rate is projected to rise to 42 percent. Obesity puts people at much greater risk for all sorts of medical problems, so they wind up in doctors’ offices and in hospitals more often than optimal weight people.

Medicine is struggling to make accommodations. Doctors often check blood pressure using cuffs meant for thighs, Razavi said. Surgical tools have to be enlarged in order to reach through layers of fat. Obese patients require higher doses of radiation during imaging tests like CT scans. “And that means if I’m doing the procedure, I am getting higher doses of radiation, too,” Razavi pointed out.

Some patients won’t fit into MRI scanners. Surgical tables have been redesigned to handle patients weighing up to 450 pounds. Needles for injections have made been longer so they can penetrate fat layers and reach muscles. Even lab tests results have to be interpreted differently.

For surgeries, Razavi said, “the ultimate compromise is that if the patient is really obese, you either do it under general anesthesia, or don’t offer it at all. It’s a judgment call,” he said. “When you tailor therapy to each patient, sometimes the risks outweigh the benefits.”

Brian Alexander is co-author, with Larry Young PhD., of "The Chemistry Between Us: Love Sex and the Science of Attraction,"  to be published Sept. 13.

 Related stories