When bowel obstruction is partial, decompression of the distended bowel may be attempted with nasogastric or intestinal tubes. Although use of these tubes may be successful in reducing edema, relieving fluid and gas accumulation, or decreasing the need for multiple stage procedures, surgery may be necessary within 24 hours if there is complete, acute obstruction. The use of self-expandable stents to decompress complete, acute malignant bowel obstruction has been noted to decrease the frequency of unnecessary surgery by permitting staging of the disease, increasing the rate of primary anastomosis relative to colostomy, and decreasing morbidity in patients with left-sided colon and rectal malignancies. Further study is warranted, including cost analysis.
Management of Chronic, Malignant Bowel Obstruction
Patients with advanced cancer may have chronic, progressive bowel obstruction that is inoperable.[6,7] The most frequent causes of inoperability are extensive tumor and multiple partial obstructions.[8,9][Level of evidence: II] A retrospective review evaluating surgical palliation of malignant bowel obstruction secondary to peritoneal carcinomatosis in 63 patients with nongynecological cancer used the ability to tolerate solid food at hospital discharge as the criterion for successful palliation. Multiple logistic regression analysis identified the absence of ascites and obstruction not involving the small bowel as predictors of successful surgical palliation in this population. Successful palliation was achieved in 45% of patients and was maintained in 76% of this group at a median follow-up of 78 days, for an overall success rate of 35%. Postoperative mortality was 15%, and postoperative complications occurred in 44% of patients.
For some patients with malignant obstructions of the gastrointestinal tract, the use of expandable metal stents may provide palliation of obstructive symptoms. Esophageal, biliary, gastroduodenal, and colorectal stents are available.[5,12,13,14,15,16,17] Stents may be placed under endoscopic guidance, with or without fluoroscopy, or by an interventional radiologist using fluoroscopy. Morbidity with stent placement may be lower than with surgery. Adequate imaging of the stricture itself and the gastrointestinal tract distal to the stricture is recommended to assess stricture length, detect multifocal disease, and determine the appropriateness of stenting.[18,19][Level of evidence: II].
When neither surgery nor stenting is possible, the accumulation of the unabsorbed secretions produce nausea, vomiting, pain, and colicky activity as a consequence of the partial or complete occlusion of the lumen. In this case, a gastrostomy tube is commonly used to provide decompression of air and fluid that may be accumulating and causing visceral distention and pain. The gastrostomy tube is placed into the stomach and is attached to a drainage bag that can be easily concealed under clothing. When the valve between the gastrostomy tube and the bag is open, the patient may be able to eat or drink by mouth without creating discomfort since the food is drained directly into the bag. Dietary discretion is advised to minimize the risk of tube obstruction by solid food. If the obstruction improves, the valve can be closed and the patient may once again benefit from enteral nutrition.