What is the comprehensive management of intestinal obstruction?

Comprehensive Management of Intestinal Obstruction

Initial Assessment and Resuscitation

Begin conservative management immediately with intravenous fluid resuscitation, nasogastric decompression, bowel rest, and analgesia for all patients unless signs of peritonitis, strangulation, or ischemia are present—which mandate emergency surgical exploration. 1, 2

Critical Clinical Evaluation

• Perform focused physical examination assessing for abdominal distension, peritoneal signs, abnormal bowel sounds, and examine all hernial orifices (inguinal, femoral, umbilical) 1, 2
• Identify red flags requiring immediate surgery: peritonitis, fever with hypotension, diffuse severe abdominal pain, or signs of bowel compromise 1, 3
• Obtain laboratory tests including complete blood count, lactate, C-reactive protein, electrolytes, BUN/creatinine, and coagulation profile 1, 2
• Elevated lactate, leukocytosis with left shift, and elevated C-reactive protein strongly suggest intestinal ischemia or peritonitis requiring urgent operative intervention 1, 4

Imaging Strategy

• Order CT scan with intravenous contrast as the preferred diagnostic modality with >90% accuracy compared to plain radiography (50-60% sensitivity) 1, 2
• CT identifies obstruction location, degree (complete vs partial), presence of closed-loop obstruction, and potential ischemia 1, 2
• Plain abdominal radiographs have limited value but may show dilated bowel loops with air-fluid levels 1, 5

Non-Operative Management Protocol

Conservative management successfully resolves 70-90% of adhesive small bowel obstructions and should be attempted for 72 hours in stable patients without peritoneal signs. 1, 2, 4

Core Conservative Measures

• Maintain strict nil per os (NPO) status 1, 2
• Insert nasogastric tube for decompression in patients with significant distension and vomiting 1, 3
• Administer intravenous crystalloid resuscitation with aggressive electrolyte monitoring and correction 1, 2, 4
• Insert Foley catheter for strict intake/output monitoring 1
• Provide appropriate analgesia for pain control 1

Water-Soluble Contrast Protocol

• Administer 80 mL of water-soluble contrast agent (Gastrografin) with 40 mL sterile water via nasogastric tube after initial resuscitation 6
• Obtain abdominal plain films at 4,8,12, and 24 hours post-administration 6
• If contrast reaches the colon within 4-5 hours, this predicts 90% resolution rate with non-operative management 1, 6
• If contrast does not reach colon within 24 hours, proceed to surgical intervention 1, 6
• Water-soluble contrast has both diagnostic and therapeutic value, significantly reducing need for surgery 1, 2, 6

Important Caveat

• Water-soluble contrast agents have higher osmolarity and may shift fluids into bowel lumen, potentially worsening dehydration—ensure adequate IV fluid resuscitation before administration 1

Surgical Intervention

Absolute Indications for Emergency Surgery

• Signs of peritonitis on examination 1, 2, 4
• Suspected strangulation or intestinal ischemia 1, 2, 4
• Closed-loop obstruction identified on CT imaging 1, 2
• Free perforation with pneumoperitoneum 2
• Hemodynamic instability (hypotension) in setting of bowel obstruction 1
• Failure of conservative management after 72 hours 1, 2, 4

Surgical Approach Selection

• Laparotomy remains the standard surgical approach for most cases requiring operation, particularly in hemodynamically unstable patients or those with diffuse peritonitis 7, 2, 4
• Laparoscopic adhesiolysis may be considered in highly selected stable patients with single adhesive band on CT, clear transition point, and minimal bowel distension 2, 4
• Laparoscopic approach carries 3-17.6% risk of iatrogenic bowel injury and higher conversion rates in emergency settings 2
• In severe sepsis/septic shock, consider damage control surgery with bowel resection, stapled intestinal ends, and temporary abdominal closure (laparostomy) 2

Adhesion Prevention

• Use adhesion barriers (hyaluronate carboxymethylcellulose) during surgery in young patients to reduce recurrence from 4.5% to 2.0% at 24 months 2, 4

Etiology-Specific Management

Small Bowel Obstruction

• Adhesions are the most common cause (even in patients without prior surgery—congenital bands or unrecognized inflammation) 2, 4
• Perform resection and primary anastomosis for small bowel tumors (adenocarcinoma, neuroendocrine, GIST, lymphoma) 7
• Internal hernias require prompt reduction, suture repair, and bowel resection if necrosis present 7

Large Bowel Obstruction

• For sigmoid volvulus without ischemia: perform endoscopic detorsion followed by same-admission sigmoid colectomy with primary anastomosis 7
• For cecal volvulus: endoscopy has no role—proceed directly to right hemicolectomy 7
• For diverticular obstruction: attempt resection and primary anastomosis in same admission after successful conservative treatment 7
• For malignant obstruction: resection and primary anastomosis is preferred unless high surgical risk or perforation present (then perform Hartmann procedure) 7
• For extraperitoneal rectal cancer causing obstruction: fashion diverting stoma to permit proper staging and neoadjuvant therapy rather than immediate resection 7

Complicated Hernias

• Prosthetic mesh repair is treatment of choice for most abdominal wall hernias (inguinal, femoral, incisional, umbilical) 7
• In cases of perforation or bowel resection with contaminated field, use suture repair instead of mesh due to infection risk 7
• Diagnostic laparoscopy can assess bowel viability after hernia reduction 7

Inflammatory Bowel Disease

• Free perforation is absolute indication for emergency surgery 2
• Trial medical therapy first for inflammatory stenoses (corticosteroids, biologics) 2
• Endoscopic balloon dilation has 89-92% technical success rate for primary or anastomotic strictures in Crohn's disease 2, 4
• Surgery is mandatory for symptomatic strictures not responding to medical therapy and not amenable to endoscopic dilation 2, 4
• Obtain endoscopic biopsies of any colorectal stricture to exclude malignancy 2

Malignant Bowel Obstruction

• For patients with years-to-months life expectancy: surgery after CT scan is primary treatment 2, 4
• For patients with advanced disease or poor performance status: prioritize pharmacologic management over surgery to optimize quality of life and enable home/hospice care 2, 4

Pharmacologic Palliative Management

• Octreotide 150 mcg subcutaneously twice daily to reduce gastrointestinal secretions—highly effective and well-tolerated 2, 4
• Opioid analgesics for pain control 2, 4
• Anticholinergic drugs to reduce secretions 2
• Corticosteroids to reduce inflammation and edema 2
• Antiemetics (avoid prokinetic agents in complete obstruction; may use in partial obstruction) 1, 2
• Consider total parenteral nutrition in patients with longer life expectancy to improve quality of life 2

Endoscopic Palliative Options

• For left-sided obstructing colon cancer: self-expanding metallic stents preferred over colostomy for palliation 2, 8
• Stent placement can bridge to elective surgery after cardiopulmonary stabilization in high-risk patients 8
• Balloon dilation followed by stenting is alternative approach 8

Radiation-Induced Obstruction

• Subacute obstruction may result from radiation-induced fibrosis, often with multiple sites of partial obstruction 7
• Trial antibiotics for small bowel bacterial overgrowth, low-fat diet if steatorrhea present, bile acid sequestrants as appropriate 7
• Surgery after pelvic radiotherapy carries significantly higher risks (anastomotic leaks, sepsis, fistulation) due to dense fibrosis—should only be performed by experienced surgeons with low threshold for proximal fecal diversion 7
• If enteric motility disorder coexists (common), surgery may not resolve symptoms 7

Chemotherapy-Associated Obstruction

• Chemotherapy can cause mesenteric ischemia presenting as acute pain or small bowel strictures 7
• Treat with nutritional support, repeated clinical assessment by experienced surgeons, and appropriate anticoagulation 7

Monitoring and Complications

Expected Complications

• Dehydration with acute kidney injury 1, 2
• Electrolyte disturbances (hypokalemia, metabolic alkalosis from vomiting) 1, 2
• Malnutrition from prolonged bowel rest 1, 2
• Aspiration pneumonia from vomiting 1, 2

Recurrence Risk

• After non-operative management: 12% readmission within 1 year, increasing to 20% after 5 years 1, 2, 4
• After operative management: 8% recurrence at 1 year, 16% at 5 years 7

Critical Pitfalls to Avoid

• Never delay surgical intervention when peritonitis, strangulation, or ischemia signs are present—these require immediate exploration 1, 4
• Do not continue conservative management beyond 72 hours without clear improvement 1, 2, 4
• Avoid using prokinetic antiemetics in complete obstruction as they may worsen symptoms 1
• Do not miss examining all hernial orifices during physical examination 1, 2
• Recognize that elevated lactate is late finding—do not wait for this to develop before considering surgery 1, 4
• In post-radiation patients, recognize that surgery is high-risk and may not resolve symptoms if motility disorder coexists 7
• Ensure all enterotomies are identified intraoperatively during laparoscopic adhesiolysis to avoid missed perforations 2