The most appropriate treatment for a gunshot wound to the hepatic flexure of the colon that cannot be repaired primarily is:
A. End colostomy and mucous fistulaNumerous large retrospective and several prospective studies have now clearly demonstrated that primary repair is safe and effective in the majority of patients with penetrating injuries. Colostomy is still appropriate in a few patients, but the current dilemma is how to select them. Exteriorized repair is probably no longer indicated since most patients who were once candidates for this treatment are now successfully managed by primary repair. Two methods have been advocated that result in 75 to 90% of penetrating colonic injuries being safely treated by primary repair. The first is to repair all perforations not requiring resection. If resection is required due to the local extent of the injury, and it is proximal to the middle colic artery, the proximal portion of the right colon up to and including the injury is resected and an ileocolostomy performed. If resection is required distal to the middle colic artery, an end colostomy is created and the distal colon oversewn and left within the abdomen. The theory behind this approach is that an ileocolostomy heals more reliably than colocolostomy, because in the trauma patient who has suffered shock and may be hypovolemic, assessing the adequacy of the blood supply of the colon is much less reliable than in elective procedures. The blood supply of the terminal ileum is never a problem. The other approach is to repair all injuries regardless of the extent and location (including colocolostomy), and reserve colostomy for patients with protracted shock and extensive contamination. The theory used to support this approach is that systemic factors are more important than local factors in determining whether a suture line will heal. Both of these approaches are reasonable and result in the majority of patients being treated by primary repairs. When a colostomy is required, regardless of the theory used to reach that conclusion, performing a loop colostomy proximal to a distal repair should be avoided because a proximal colostomy does not protect a distal suture line. All suture lines and anastomoses are performed with the running single-layer technique.