The systematic review of evidence also shows that the practice may increase the risk of some postoperative complications.
Cessation of bowel activity is one of the body's responses to the trauma of surgery for conditions such as appendicitis, gallstones, stomach and intestinal cancer, gynecological disorders and abdominal injury. Resumption of digestive processes is the key factor that determines when these surgical patients can leave the hospital.
"Hospital stay has been the buzzword of the last 20 years because that's what costs all the money," says lead author Dr. Richard Nelson, a colorectal surgeon at the University of Illinois College of Medicine. "We'd send everybody home the same day if we thought they could eat," he says.
The rationale for routinely inserting a flexible tube through the nose and into the stomach has been that keeping the digestive tract empty would help it restart more quickly. Surgeons also commonly believe that the practice reduces the likelihood of vomiting and related aspiration pneumonia.
This reasoning may look good on paper, says Nelson, but like many medical practices of the past it was based more on intuition than evidence.
"When I was a resident every person who had a cut in their tummy had a nasogastric tube put in when they went to sleep and we left it in until they had a formed stool eight to 10 days later," says Nelson. "It was just routine. It sounded good, sounded rational."
A 1995 review of abdominal surgery trials showed that except for vomiting and bloating, patients actually fared better without the routine use of nasogastric tubes. However in some of the studies tube use was not randomly assigned, which may have produced biased results.
To conduct a more rigorous analysis including numerous recent studies, Nelson and his co-authors identified 28 randomized controlled trials of emergency or elective abdominal surgeries. They did not include studies of laparoscopic surgeries or those involving gastrostomy -- an artificial opening directly to the stomach.
In the eligible trials, a total of 4,194 patients had been randomly assigned to one of two groups: those with a nasogastric tube in place until intestinal function returned or those with either no tube or tube removal within 24 hours of surgery.
The review revealed that the "selective tube use" approach results in earlier return of bowel function with no significant increase in pulmonary complications. Although the evidence suggests that routine tube use may lead to a very slight decrease in wound infection and related hernia, Nelson contends that other measures could also achieve this benefit.
"Routine nasogastric decompression does not accomplish any of its intended goals and so should be abandoned in favor of selective use of the nasogastric tube," the authors conclude.
The review appears in the January issue of The Cochrane Library, a publication of The Cochrane Collaboration, an international organization that evaluates medical research. Systematic reviews draw evidence-based conclusions about medical practice after considering both the content and quality of existing medical trials on a topic.
"Some Cochrane reviews answer questions so definitively that you think, 'Let's put this issue to bed,'" says Nelson. In the case of routine tube use, Nelson says the lack of benefits is so clear one has to ask, "Why do it?"
Dr. Neil Hyman of the University of Vermont College of Medicine understands why some surgeons may continue the practice. "The reason that most people do things is because at one point somebody told them in their training it was the right thing … There's no surgeon who wants to do the wrong thing."
As chair of the American Society of Colon and Rectal Surgeons' Standards Committee, Hyman is leading an effort to develop guidelines to inform surgeons of the latest evidence-based treatments.
Although there is broad support for this approach, according to Hyman, all involved recognize that such guidelines can't be applied to every operation. "They're really just principles that need to be taken to the bedside and applied to the situation that you're confronting with a particular patient. We really hope to provoke thought … to create a critical re-evaluation of our routine practice."
What does all this mean for someone facing abdominal surgery? "If the doctor says you're going to wake up with a tube in your nose, the informed patient has a right to ask 'Why?'" says Nelson. Unless there's a specific need to use a tube, such as a history of previous abdominal surgeries or a bowel obstruction, the surgeon shouldn't, he says.
FOR MORE INFORMATION
Health Behavior News Service: (202) 387-2829, press@cfah.org
Interviews: Contact Richard Nelson, 312-996-6935, altohorn@uic.edu 1. Nelson et al. Prophylactic nasogastric decompression after abdominal surgery. The Cochrane Database of Systematic Reviews 2005, Issue 1
The Cochrane Collaboration is an international nonprofit, independent organization that produces and disseminates systematic reviews of health care interventions and promotes the search for evidence in the form of clinical trials and other studies of interventions. Visit http://www.cochrane.org for more information
By Laura Kennedy, Contributing Writer
Health Behavior News Service