Management of Large Bowel Obstruction
The management of large bowel obstruction requires immediate supportive care followed by cause-specific surgical intervention, with resection and primary anastomosis being the preferred approach for most etiologies when feasible, reserving staged procedures only for high-risk patients or those with perforation. 1, 2
Initial Resuscitation and Assessment
All patients require aggressive supportive care immediately:
- Intravenous crystalloid fluid resuscitation to correct hypovolemia 2
- Nasogastric tube decompression to reduce proximal bowel distension 2
- Foley catheter insertion to monitor urine output and assess volume status 2
- NPO status to minimize intestinal workload 2
- Electrolyte monitoring and correction 2
Obtain multidetector CT scan with intravenous contrast as the imaging modality of choice to determine the cause, location, and presence of complications (ischemia, perforation) 2. This is critical for surgical planning and should not be delayed in stable patients 2.
Monitor continuously for signs of clinical deterioration including peritonism, increasing white blood cell count, and rising lactate, as these mandate immediate surgical intervention 2.
Cause-Specific Surgical Management
Sigmoid Volvulus
For sigmoid volvulus without ischemia or perforation, perform endoscopic detorsion followed by same-admission sigmoid colectomy with primary anastomosis 1, 2. This is the best strategy to prevent recurrence, which is high with endoscopic therapy alone 2.
- Reserve endoscopic detorsion alone only for high-surgical-risk patients who cannot tolerate surgery 1, 2
- If ischemia is present or endoscopic derotation fails, proceed immediately to emergency surgery 1, 2
- Laparoscopic approach has limited utility due to the absence of sigmoid fixation and excessive colonic length 1, 2
Cecal Volvulus
Endoscopy has no role in cecal volvulus—proceed directly to right hemicolectomy 1, 2. This is the only appropriate treatment option 1.
Diverticular Obstruction
Resection with primary anastomosis is the preferred procedure after successful conservative treatment during the same admission, regardless of bowel preparation status 1, 2.
- For high-risk patients, consider exclusively conservative therapy or Hartmann procedure 1, 2
- Most diverticular obstructions are incomplete and resolve with conservative management initially 1
Malignant Large Bowel Obstruction
Resection with primary anastomosis is the best option for patients without significant risk factors or perforation 1, 2. Anastomotic leak rates of 2.2-12% in emergency settings are comparable to the 2-8% rate in elective procedures 1, 2.
For high-risk patients or those with perforation, perform a staged procedure such as Hartmann procedure 1, 2.
Special considerations for malignant obstruction:
- For left-sided colonic cancer, self-expanding metallic stents as a bridge to elective surgery offer better short-term outcomes than emergency surgery 2
- For extraperitoneal rectal cancer, postpone primary tumor resection and create a diverting stoma to permit proper staging and appropriate neoadjuvant treatment 1, 2
- Laparoscopic approach should be limited to selected cases in specialized centers 1, 2
- Stents are increasingly important in converting emergency operations to elective cases with decreased complications and stoma formation 2
Critical Pitfalls to Avoid
Never delay surgery when signs of ischemia or perforation are present 2. The high mortality associated with colonic perforation in LBO demands decisive surgical decision-making 3.
Do not attempt endoscopic management of cecal volvulus—this wastes time and increases morbidity 1, 2.
Avoid exclusively endoscopic therapy for sigmoid volvulus in surgical candidates, as recurrence rates are prohibitively high without definitive resection 2.
Do not perform primary tumor resection for extraperitoneal rectal cancer presenting with obstruction—this compromises oncologic outcomes by preventing proper neoadjuvant therapy 1, 2.
Monitoring During Management
Closely monitor for clinical deterioration including development of peritonism, rising inflammatory markers, and increasing lactate 2.
Immediate surgery is necessary if signs of deterioration develop during attempted conservative management 2.
Regular reassessment is essential to determine if surgical intervention becomes necessary for patients initially managed conservatively 2.