Preventing a dangerous complication of colon surgery
October 12, 2015
About 300,000 Americans undergo colon surgery each year, oftentimes to remove cancer or polyps. For most patients, the surgery is uneventful. But a baffling and dangerous complication of colon and rectal surgery has plagued the field for years. It involves a leak from the colon where the incision was made and reconstructed.
The condition, called an anastomotic leak, affects at least 25,000 patients a year in the United States, including about 10 to 15 percent of patients who have rectal cancer surgery. Dr. Michael J. Stamos
, a UC Irvine Health surgeon and chair of the Department of Surgery, is leading a large, national study on a way to prevent anastomotic leaks. He compares the problem to a leak that springs after a plumber comes to your house to fix a pipe.
“He takes the pipes apart and clears the trap and puts it back together again,” he says. “Then you run water and look down and see water on the ground. The same thing happens with an anastomotic leak. The intestinal contents are leaking outside of the bowel after you remove a segment and reattach it."
With standard operating-room light, the surgeon can’t visualize where there is diminished blood supply to the colon, a long purported cause of leaks. When a leak occurs, the consequences to patients are dire, Stamos says. More than half of the deaths following colon and rectal surgery are caused by anastomotic leaks. Some patients need a second or even third operation and may be left with scarring or a colostomy.
“For many decades we’ve struggled with how to prevent leaks and understand why they occur,” Stamos says.
However, the potential solution lies in an imaging technology called fluorescence angiography. This technology has been used for years to make sure the blood is flowing normally after heart surgery. A fluorescent dye is injected into the bloodstream that can be seen with a special light source and camera to show how the blood to the colon is flowing.
A few years ago, Stamos and representatives of the company that makes the device decided to test its ability to prevent anastomotic leaks. The results of that study, called the PILLAR II study, showed poor blood supply in nine of 139 patients.
“In those patients, it looked like they had good blood supply, from what we could tell by feeling, touching and using standard white light. But in fact there was inadequate blood supply,” which can cause a leak, he says. In those nine cases, surgeons removed an additional inch or so of the colon to ensure optimal blood supply, and none of the patients developed a leak.
“The first set of data was quite encouraging. The rate of leaks was verylow compared to historical data. We were surprised and encouraged to do more studies,” says Dr. Alessio Pigazzi, chief of the Division of Colon & Rectal Surgery.
Stamos is now leading the Phase 3, randomized, controlled study of the technology, which will involve at least 550 patients at 21 sites nationwide. Pigazzi is the lead investigator for the UC Irvine Health arm of the study.
“Because of the magnitude and impact of the problem, there is very broad interest in our research,” Pigazzi says.
UC Irvine Health experts are proud to pave the way for this advance, Stamos says.“It’s our mission to discover, teach and heal. ‘Discover’ is first for a reason. It’s what differentiates us. It allows us to do a better job of healing.”
— UC Irvine Health Marketing & Communications
Featured in UC Irvine Health Live Well Magazine Fall 2015.