The etiology is often intraoperative manipulation, electrolyte abnormalities, narcotics, peritonitis, abscess, hematoma, or fistula.
Signs are nausea and vomiting, hypoactive or absent bowel sounds, and abdominal distension.
Workup is with laboratories and physical examination.
Treatment: the patient can be made nothing by mouth (NPO), intravenous fluid (IVF) initiated, and consideration given to a nasogastric tube (NGT). If the ileus does not resolve, imaging can be obtained with a CT scan of the abdomen and pelvis with oral Gastrografin contrast to rule out an obstruction. Abdominal imaging provides no difference in clinical treatment between obstruction and ileus as they will both be managed with NPO/NGT/electrolyte replacement upfront. If abscess is seen with CT, a percutaneous drain can be placed with antibiotics as indicated.
• Bowel obstructions: partial obstructions can resolve spontaneously in 50% of cases. Complete obstructions usually need surgical intervention.
Small-bowel obstruction (SBO)
The etiology can be adhesions or herniation from surgery, bowel kinking, tumor, radiation therapy (XRT) induced ischemia, and stricture.
Signs are nausea and vomiting. Bowel sounds are present and can be high pitched and hyperactive. Abdominal distension is present, and absence of flatus is common.
Workup is with lab tests, a physical examination, and CT scan of the abdomen and pelvis with PO Gastrografin contrast.
The patient should be made NPO, an NGT placed to low intermittent wall suction (LIWS), pain medication administered, and IVF should be initiated. Correction of electrolyte abnormalities is important in addition to antiemetics and pain management. Occasionally, high-dose steroids can reduce periluminal inflammation and have antiemetic properties. Partial obstructions can resolve with conservative management, but fewer than 50% of complete obstructions resolve similarly.
Large-bowel obstruction (LBO)
Etiology can be a mass causing obstruction intrinsically (intraluminal tumor), extrinsically (pelvic tumor compression), or stricture from transmural invasion.
Signs: LBO can have a delayed time to presentation with a lower amount of emesis.
252Workup is indicated with imaging:
CT scan of abdomen and pelvis with Gastrografin should be obtained. This can document the site of obstruction and may occasionally be therapeutic.
Barium enema: can occasionally be therapeutic. This study should be performed before a CT scan or small bowel follow-through.
To manage conservatively: the patient should be made NPO, an NGT should be placed to LIWS, IV fluids and pain control should be instituted, and antiemetics should be given.
To manage surgically:
IV second-generation cephalosporins should be given prior to surgical correction.
Resection with end-to-end anastomosis, loop, or end ostomy with mucous fistula can be performed.
Stenting may occasionally be useful if the patient is a poor surgical candidate.
Enemas in partial LBO can either be therapeutic or can convert the obstruction to a complete obstruction by inducing colonic spasm.
If the patient chooses to forego extensive surgery, consider endoscopy with stent placement or diversion via end ostomy.
When considering whether to perform surgical reduction of an obstruction in a cancer patient, it is important to take into account the patient’s social factors; the expected outcome; the patient’s life expectancy; and the etiology and the extent of obstruction (e.g., recurrent cancer, XRT stenosis).
• Bowel perforation:
Etiology: perforation can occur from an unrecognized enterotomy, intestinal devascularization, tumor infiltration of the bowel wall, bowel infarction (from thrombus, atrial fibrillation), or even certain chemotherapy agents (bevacizumab up to 1%–11%, paclitaxel 2%).
Signs are peritonitis, pain, abdominal distension, and fever.
Workup: imaging with abdominal x-ray or CT demonstrating free air under the diaphragm. Treatment is with emergent surgical exploration and antibiotics. Cecal perforation tends to occur if the cecum is dilated to, or greater than, 10 cm as seen on imaging.
Treatment is with loop or end ostomy with mucous fistula, or ileostomy.
• Pneumoperitoneum after laparotomy should be considered when ruling out a bowel perforation. Table 4.5 demonstrates the time from surgery and percent of patients with residual abdominal air present.
Radiograph percent positive
CT scan percent positive
Postoperative day 3
Postoperative day 6
• Anastomotic bowel leak after a bowel resection can occur in up to 15% of patients. Prevention is avoidance of the bowel watershed areas. When performing an anastomosis, universal principles should be followed ensuring adequate vascularization of both ends of the bowel, absence of tumor at the anastomotic site, a tension-free anastomosis, and an adequate bowel lumen. Bowel viability can be ascertained with IV fluorescein dye and a Wood’s lamp at the time of resection and reanastomosis, or with Doppler ultrasound.
Signs: leaks tend to present with nausea, ileus, abdominal pain, fever, and occasionally leakage of feculent material through the wound.
Workup: includes physical exam, lab tests, and a CT of the abdomen and pelvis with PO Gastrografin.
Treatment: a drain needs to be placed, the patient made NPO, broad-spectrum antibiotics given, and consideration for surgical intervention with intestinal diversion. The diversion can usually be taken down in about 2 months, after imaging with PO contrast shows no evidence of continued leakage or after completion of chemotherapy in abdominal cancer patients and no evidence of recurrent disease (6-12 months).
• Bowel fistula (enterocutaneous, enterovaginal, enterovesicle):
Signs: fistulae can present as feculent discharge from a surgical wound or the vagina.
Workup: diagnosis is with a CT of the abdomen and pelvis with PO Gastrografin contrast or a fistulagram. Oral activated charcoal or isosulfan blue can also be given to evaluate for color change that would indicate a fistula.
Treatment: an NGT should be placed, the patient made NPO, and total parenteral nutrition (TPN) initiated. Wound care should be performed, and consideration given to administration of somatostatin. If there is no resolution of the fistula with these conservative measures, surgical resection of the fistulous tract with bowel resection and temporary diversion or primary reanastomosis with protective loop ileostomy should be performed. Staged repair with a diverting loop colostomy, primary fistula repair, and ostomy take-down approximately 2 months later is the preferred option as massive inflammation can hamper primary anastomosis and compromise fistula repair.
• Stoma complications usually involve stomal retraction or devitalization.
Etiology: this occurs from tension or decreased blood flow to the distal bowel edges.
Signs include a dusky appearance, necrosis, or retraction.
Workup: evaluation of viability includes placement of a test tube or blood vial inside the stoma to assess the depth/extent of damage.
Treatment is based on location of devitalization. If it is limited to the distal segment above the fascia, observation and wound care are indicated. If there is necrosis beneath the fascia, surgical revision is necessary.
• Ostomy herniation or prolapse usually occurs in patients whose ostomy was placed lateral to the rectus muscles.
Prolapse occurs in 1% to 3% of patients with an ostomy.
Etiology: it is often due to a stoma that is too long or wide, increased intra-abdominal pressure, extensive weight loss, or a redundant sigmoid colon.
Treatment: conservative measures are placement of a rigid appliance with a tight belt. Treatment is resection of the protruding segment of colon with nipple reconstruction. Care should be taken to rule out those with a hernia so there is no loop transection risk.