Large Bowel Obstruction Management (WSES 2018)

Algorithm Steps

1. ▶

   Start

   Suspected Large Bowel Obstruction

   Abdominal distension, obstipation, vomiting (late), crampy abdominal pain. Etiology: 60% colorectal cancer, 20% diverticular disease, 5% volvulus, others.

   1. ●

      Action

      Diagnostic Workup

      1) CT abdomen/pelvis with IV + rectal contrast: Gold standard - identifies transition point, etiology, signs of ischemia/perforation. 2) Plain AXR: Dilated colon >6cm, no gas in rectum. 3) Labs: CBC, BMP, lactate, CEA if cancer suspected.

      1. ◆

         Decision

         Complete Obstruction Confirmed?

         CT showing transition point, dilated proximal colon, decompressed distal colon. Rule out pseudo-obstruction (Ogilvie) - no transition point, history of recent surgery/illness/medications.

         1. ◆

            Decision

            Signs of Perforation or Ischemia?

            Perforation: Free air, extraluminal contrast. Ischemia: Mucosal enhancement loss, pneumatosis, mesenteric stranding, portal venous gas. Cecal diameter >12cm = impending perforation risk.

            1. ⚠

               Warning

               ⚠️ Cecal Diameter >12cm

               High risk of imminent perforation even without current signs. Emergency surgery should not be delayed. Cecal perforation has high mortality.

            2. ●

               Action

               Emergency Laparotomy

               Perforation or ischemia requires immediate surgery. No role for SEMS. Resection of affected segment + source control. Anastomosis vs ostomy based on patient stability and contamination.

               1. ●

                  Action

                  Postoperative Management

                  1) Enhanced recovery protocol. 2) Oncology referral for cancer staging/adjuvant therapy. 3) Stoma education if applicable. 4) Nutritional support. 5) VTE prophylaxis. 6) Monitor for anastomotic leak if primary anastomosis.

                  1. ✓

                     Outcome

                     Obstruction Relieved

                     Bowel decompressed. Continue oncologic workup and treatment. Plan ostomy reversal if applicable.

            3. ◆

               Decision

               Location of Obstruction?

               Right-sided: Cecum to hepatic flexure. Left-sided: Splenic flexure to sigmoid. Location determines surgical approach.

               1. ●

                  Action

                  Right-Sided Obstruction

                  Preferred: Right hemicolectomy with primary ileocolic anastomosis (one-stage). Safe in most patients even in emergency. Advantages: Single surgery, no ostomy, complete oncologic resection.

               2. ◆

                  Decision

                  Left-Sided Obstruction - Options

                  Consider patient fitness, tumor characteristics, institutional expertise. Options: 1) Hartmann's procedure. 2) SEMS as bridge to surgery. 3) Resection + primary anastomosis + loop ileostomy.

                  1. ◆

                     Decision

                     SEMS Candidate?

                     Consider SEMS if: Curative intent, tumor accessible to endoscopy, no perforation, patient can tolerate colonoscopy, expertise available. Contraindicated if: Perforation, peritonitis, >4cm tumor length, complete obstruction preventing scope passage.

                     1. ●

                        Action

                        SEMS as Bridge to Surgery

                        Endoscopic placement of self-expanding metal stent. Decompress colon over 5-14 days. Allows: Bowel prep, staging workup, nutritional optimization. Then elective laparoscopic resection with primary anastomosis. Lower ostomy rate.

                     2. ●

                        Action

                        Hartmann's Procedure

                        Sigmoid/left colon resection with end colostomy and rectal stump closure. Safest option in: High-risk patients, severe contamination, hemodynamic instability. Ostomy reversal possible but <50% actually reversed.

                  2. ●

                     Action

                     Resection + Primary Anastomosis

                     Left colectomy with primary colorectal anastomosis. Consider: 1) On-table lavage to decompress colon. 2) Subtotal colectomy with ileocolic anastomosis. 3) Protecting loop ileostomy. Higher leak risk in emergency but avoids permanent ostomy.

               3. ●

                  Action

                  If Volvulus Identified

                  Sigmoid volvulus: Attempt endoscopic derotation first (if no ischemia). If successful, plan semi-elective sigmoid resection. If necrosis/perforation: Emergency laparotomy. Cecal volvulus: Surgery required - right hemicolectomy or cecopexy.