There's good news for patients who need colon or rectal surgery: you may be able to skip the “cleaning out” procedure that we do before a colonoscopy. Researchers in Italy demonstrated in a randomized trial that results were equally favorable with and without this standard preparation.
In patients with abdominal wounds that cause penetrating trauma to the colon, surgeons typically perform emergency surgery without the “cleaning out” preparation. Many studies have shown that it is safe to connect two parts of the colon in a procedure called anastomosis under urgent conditions. Thus, some researchers have questioned whether bowel preparation is beneficial in cancer surgery. The preparation procedure is not completely harmless in itself. The laxatives may cause electrolyte imbalance and dehydration, which are more serious in cancer surgery than in the simpler procedure of colonoscopy.
In addition, colonoscopy and cancer surgery have different conditions. Standard preparation for colonoscopy often leaves some amount of liquid stool, which is not a problem for screening because it can be removed with a medical vacuum cleaner. In surgery, however, liquid stool is more difficult to manage than solid stool.
Reference 1 reports a study of 120 patients with standard bowel preparation, and 124 without this preparation. All had colorectal surgery in the oncologic unit. There was no significant difference in the outcomes for the two groups. One patient from each group died from sepsis. The average length of hospital stay was 11.9 days for the prep group, and 11.0 days for the no-prep group.
The authors suggested that bowel preparation should be treated as any other medication, used only when indicated. Colonoscopy may be performed as part of the cancer surgery in some cases, and this would be a indication for preparation.
Historically, the mortality rate from colorectal surgery was over 20 percent in the first half of the 20th century. Most of these deaths were due to sepsis, attributed in part to infection from fecal material. As surgical techniques have improved, physicians have placed great emphasis on removing all potential sources of infection.