Skip to main content

For urgent surgical problems, please contact the nearest hospital emergency department.

Intestinal Obstruction (Bowel Obstruction)

Typical recovery: Recovery varies greatly with the cause and severity of obstruction. An uncomplicated adhesive small-bowel obstruction that resolves without surgery may improve over one to several days, followed by gradual return to diet and activity. Recovery after surgery usually takes several weeks and is longer when bowel resection, peritonitis, sepsis or a stoma is involved. The underlying cause, rather than the diagnosis of obstruction alone, determines the long-term treatment and recurrence risk.

Key points

  • Bowel obstruction is a surgical emergency that requires assessment even though not every patient ultimately requires an operation.
  • Small-bowel and large-bowel obstruction have different common causes and sometimes different treatment strategies.
  • Adhesions from previous abdominal surgery are a major cause of small-bowel obstruction.
  • An adhesive obstruction can occur many years after the original abdominal operation.
  • A patient who has never undergone abdominal surgery can still develop small-bowel obstruction; hernia, tumour and other causes must be considered, and adhesions can occasionally occur even in a virgin abdomen.
  • An obstructed external hernia must be actively looked for during examination.
  • Passing stool or gas does not completely exclude bowel obstruction, particularly early in the illness or in partial obstruction.
  • Vomiting may be prominent early in proximal small-bowel obstruction but can occur later in distal or large-bowel obstruction.
  • CT abdomen and pelvis with intravenous contrast is usually the most useful initial cross-sectional investigation for acute suspected small-bowel obstruction.
  • CT helps determine the transition point, likely cause and whether there are features suggesting a closed loop, strangulation, ischaemia or perforation.
  • Plain abdominal X-rays may show bowel dilatation and air-fluid levels but provide less information than CT about the cause and complications of obstruction.
  • A simple adhesive small-bowel obstruction without evidence of ischaemia or peritonitis often resolves without surgery.
  • Non-operative treatment includes fasting, intravenous fluids, correction of electrolytes and gastrointestinal decompression when clinically necessary.
  • Non-operative management is not passive observation; repeated examination and monitoring are essential.
  • For appropriately selected adhesive small-bowel obstruction, a trial of non-operative management of up to approximately 72 hours is generally considered reasonable, provided the patient remains clinically stable and there are no signs of strangulation or ischaemia.
  • The presence of peritonitis, strangulation or bowel ischaemia is a contraindication to prolonged conservative management.
  • Clinical deterioration overrides any planned duration of conservative treatment.
  • A water-soluble contrast challenge can help predict resolution of adhesive small-bowel obstruction.
  • When water-soluble contrast reaches the colon within about 24 hours, non-operative resolution is more likely.
  • Failure of contrast progression, persistent obstruction or clinical deterioration prompts reassessment for surgery.
  • Continuous severe pain, increasing tenderness, tachycardia, fever, metabolic deterioration or peritonitis raise concern for compromised bowel.
  • Normal early laboratory tests do not reliably exclude strangulation or bowel ischaemia.
  • Closed-loop obstruction is particularly important because a segment of bowel can become obstructed at two points and rapidly lose its blood supply.
  • Surgery for obstruction may involve adhesiolysis, hernia repair, bowel resection, tumour surgery or formation of a temporary or permanent stoma depending on the cause and bowel viability.
  • Laparoscopic surgery can be useful in carefully selected adhesive obstructions, but extensive adhesions or markedly distended bowel may make open surgery safer.
  • Malignant large-bowel obstruction requires a different strategy from routine adhesive small-bowel obstruction; selected patients may be candidates for endoscopic colonic stenting as a bridge to surgery or for palliation.
  • Recurrence is possible after both non-operative and operative treatment of adhesive small-bowel obstruction.

Overview

Intestinal obstruction, also called bowel obstruction, occurs when the normal passage of intestinal contents is partly or completely blocked. The obstruction may involve the small intestine or the large intestine. Common causes of small-bowel obstruction include adhesions from previous abdominal surgery, abdominal-wall or internal hernias, tumours and inflammatory strictures. Large-bowel obstruction may be caused by colorectal cancer, volvulus, diverticular or other strictures and several less common conditions. The important clinical question is not only whether an obstruction is present, but whether the affected bowel remains viable. A simple obstruction may sometimes settle with bowel rest, intravenous fluids and decompression, particularly when it is caused by postoperative adhesions. A strangulated or closed-loop obstruction can compromise the bowel's blood supply and progress to ischaemia, necrosis and perforation, requiring urgent surgery. Symptoms commonly include colicky abdominal pain, abdominal distension, vomiting and reduced passage of stool or gas, but the pattern varies with the site and severity of obstruction. CT scanning is central to modern evaluation because it can identify the transition point, likely cause, severity and features suggesting compromised bowel. Treatment is therefore individualised according to the cause, clinical condition, CT findings and response to initial management.

Signs & symptoms

  • Cramping or colicky abdominal pain that comes in waves.
  • Increasing abdominal distension or bloating.
  • Nausea and vomiting.
  • Vomiting that may become frequent in high small-bowel obstruction.
  • Reduced or absent passage of stool and gas in complete obstruction.
  • Continued passage of some stool or gas in partial obstruction or during the early phase of an obstruction.
  • Constipation or obstipation.
  • A feeling of abdominal fullness.
  • Dehydration, thirst and reduced urine output from vomiting and fluid sequestration.
  • Continuous rather than intermittent abdominal pain when strangulation or bowel ischaemia develops.
  • Fever, rapid pulse, increasing tenderness or systemic illness in complicated obstruction.
  • A painful irreducible groin, umbilical or incisional swelling when an obstructed hernia is the cause.

How assessment and treatment are planned

  1. 1

    Assess the patient's vital signs, degree of dehydration and overall clinical stability.

  2. 2

    Take a focused history including previous abdominal surgery, hernias, malignancy, inflammatory bowel disease, previous bowel obstruction and the onset and progression of symptoms.

  3. 3

    Examine the abdomen for distension, tenderness, guarding, rigidity, bowel sounds, previous surgical scars and abdominal-wall or groin hernias.

  4. 4

    Obtain appropriate blood tests to assess dehydration, renal function, electrolyte disturbance, inflammation and possible tissue hypoperfusion.

  5. 5

    Perform CT of the abdomen and pelvis, usually with intravenous contrast when appropriate, to confirm obstruction, identify its level and cause and assess for closed-loop obstruction, ischaemia or perforation.

  6. 6

    Keep the patient fasting during acute management.

  7. 7

    Correct dehydration and electrolyte abnormalities with intravenous fluids.

  8. 8

    Use nasogastric decompression when clinically indicated, particularly with significant vomiting or gastric and intestinal distension.

  9. 9

    Provide analgesia, antiemetics and appropriate supportive care.

  10. 10

    For selected adhesive small-bowel obstruction without peritonitis, strangulation, ischaemia or other immediate surgical indication, begin carefully monitored non-operative management.

  11. 11

    Consider a water-soluble contrast challenge in suitable adhesive small-bowel obstruction to help predict whether the obstruction is likely to resolve without surgery.

  12. 12

    Perform repeated clinical examinations and reassess laboratory and imaging findings because deterioration can occur during conservative treatment.

  13. 13

    Proceed to urgent surgery when there is peritonitis, bowel ischaemia, strangulation, perforation, an irreducible obstructed hernia or another cause requiring immediate operative treatment.

  14. 14

    Consider surgery when an apparently uncomplicated obstruction fails to resolve during an appropriate period of non-operative management.

  15. 15

    During surgery, identify and relieve the cause of obstruction.

  16. 16

    Divide obstructing adhesions when adhesions are the cause.

  17. 17

    Reduce and repair an obstructed hernia when appropriate.

  18. 18

    Assess bowel viability carefully and resect non-viable or perforated bowel when necessary.

  19. 19

    Treat obstructing tumours according to their location, stage, patient condition and available specialist expertise; options can include resection, diversion or selected endoscopic stenting for malignant large-bowel obstruction.

  20. 20

    Use a laparoscopic approach in selected suitable cases of simple adhesive small-bowel obstruction when anatomy and surgical expertise make this safe.

Preparation

  • Bring details of previous abdominal operations, including approximate dates and the reason for surgery.
  • Bring previous CT scans, operative notes or discharge summaries if available.
  • Tell the surgical team about previous episodes of bowel obstruction and whether they resolved without surgery.
  • Mention any known abdominal-wall, groin or incisional hernia.
  • Tell the team about known bowel cancer, inflammatory bowel disease, abdominal radiotherapy or previous abdominal infection.
  • Report when you last passed stool and gas.
  • Tell the clinician when vomiting started and approximately how often it has occurred.
  • Bring a complete medication list, especially anticoagulants and antiplatelet medicines.
  • Do not take laxatives or bowel-cleansing preparations when mechanical bowel obstruction is suspected unless specifically advised by the treating team.
  • Do not eat or drink until the treating team has assessed whether bowel rest or surgery may be required.
  • If urgent surgery is required, anaesthesia and operative preparation will proceed according to your clinical condition rather than waiting for routine elective preparation.

Recovery and aftercare

  • After successful non-operative treatment, diet is restarted gradually according to return of bowel function and the treating team's advice.
  • Maintain adequate hydration during recovery.
  • Return urgently if colicky pain, persistent vomiting, progressive distension or inability to pass gas recurs.
  • After surgery, early mobilisation is encouraged when medically appropriate.
  • Follow postoperative instructions for wound care, activity and diet.
  • If bowel was resected, follow any additional nutritional or bowel-function advice provided by the surgical team.
  • If a temporary stoma was created, receive formal stoma-care education before discharge.
  • After obstruction caused by a tumour, attend the planned histopathology, staging and multidisciplinary oncology follow-up.
  • After an obstructed hernia has been repaired, follow the postoperative hernia-care plan.
  • Previous adhesive obstruction can recur, so future episodes of similar pain, vomiting and distension deserve early medical assessment.
  • There is no reliable medicine, massage or home remedy that can safely open a mechanical bowel obstruction.

Risks and possible complications

  • Severe dehydration.
  • Electrolyte disturbance.
  • Acute kidney injury.
  • Aspiration of vomit into the lungs.
  • Progressive bowel distension.
  • Strangulation of the obstructed bowel.
  • Loss of blood supply and bowel ischaemia.
  • Bowel necrosis.
  • Bowel perforation.
  • Peritonitis and intra-abdominal infection.
  • Sepsis and organ failure.
  • Need for emergency bowel resection.
  • Need for temporary or permanent stoma formation in selected cases.
  • Postoperative wound or intra-abdominal infection.
  • Postoperative ileus.
  • Formation of additional adhesions following abdominal surgery.
  • Recurrent bowel obstruction.
  • Short-bowel problems are possible if an unusually large length of non-viable intestine has to be removed.

When to go to an emergency department now

  • Severe cramping abdominal pain associated with repeated vomiting and progressive abdominal distension.
  • Inability to pass stool or gas associated with abdominal pain or vomiting.
  • Continuous severe abdominal pain rather than intermittent cramps.
  • Increasing abdominal tenderness, guarding or rigidity.
  • Fever, rapid heartbeat, faintness, confusion or marked weakness with symptoms of obstruction.
  • Persistent vomiting with reduced urine output, dizziness or other signs of significant dehydration.
  • A painful groin, umbilical or previous-incision hernia that cannot be pushed back, particularly when associated with vomiting or abdominal pain.
  • Blood in stool associated with severe abdominal pain or obstruction symptoms.
  • Sudden worsening of pain after a period of apparently stable obstruction.
  • Abdominal distension and vomiting in a patient with previous major abdominal surgery or previous bowel obstruction.

Myth vs fact

Frequently asked questions

Sources

Medically reviewed by Dr. Shams Alam Mohammed Tahir, MBBS, MS (General Surgery). Last reviewed 2026-09-18.

WhatsApp