Intestinal Obstruction

Intestinal obstruction is a COMMON SURGICAL EMERGENCY, a mechanical blockage of bowel lumen. For Zambian students, ETIOLOGIES reflect local epidemiology: ADHESIONS (most common, 60%, post-surgical), HERNIA (external: inguinal, femoral; internal), TUMOUR (colorectal, metastatic), VOLVULUS (sigmoid > cecal, high incidence in Africa), INTUSSUSCEPTION (children), CROHN'S DISEASE (stricture), GALLSTONE ILEUS (elderly, female). CLASSIFICATION: SMALL BOWEL OBSTRUCTION (SBO) vs LARGE BOWEL OBSTRUCTION (LBO). PARTIAL vs COMPLETE. SIMPLE vs STRANGULATED (ischemia, necrosis, perforation). CLINICAL: SBO: ABDOMINAL PAIN (colicky, periumbilical), VOMITING (early, bilious), ABSOLUTE CONSTIPATION (late, complete obstruction), ABDOMINAL DISTENSION (mild). LBO: CONSTIPATION (early), ABDOMINAL DISTENSION (marked), PAIN (crampy, lower), VOMITING (late, feculent). PHYSICAL EXAM: tachycardia, fever (strangulation), abdominal tenderness, distension, high-pitched tinkling bowel sounds (early), silent abdomen (late, peritonitis), HERNIA ORIFICES (always check!), SCARS (adhesions). SIGMOID VOLVULUS: massive distension, tympanic. INTUSSUSCEPTION: 'red-currant jelly' stool, palpable sausage-shaped mass (children). DIAGNOSIS: PLAIN ABDOMINAL X-RAY (SUPINE + ERECT): dilated bowel loops (>3cm small bowel, >6cm colon), air-fluid levels, 'step-ladder' pattern (SBO), 'coffee-bean' sign (sigmoid volvulus), 'bird-beak' (barium enema). CT ABDOMEN (with IV/PO contrast): GOLD STANDARD, identifies level, cause (mass, adhesion, hernia, volvulus), strangulation (pneumatosis, portal venous gas, bowel wall thinning, poor enhancement). LABS: leukocytosis, elevated lactate (strangulation), electrolytes, creatinine (dehydration). MANAGEMENT: RESUSCITATION: IV FLUIDS (crystalloids), CORRECT ELECTROLYTES, NGT (decompression, vomiting). URINARY CATHETER (monitor output). BROAD-SPECTRUM ANTIBIOTICS (if strangulation/peritonitis suspected). SURGICAL CONSULTATION. NON-OPERATIVE MANAGEMENT (SBO, partial, simple, no strangulation): NGT, NPO, IV fluids, serial abdominal exams. 60-80% resolve. OPERATIVE MANAGEMENT: INDICATIONS: COMPLETE OBSTRUCTION, STRANGULATION (peritonitis, fever, tachycardia, leukocytosis, lactate), FAILED NON-OPERATIVE (48-72h), specific etiologies (malignancy, hernia, volvulus, gallstone ileus). PROCEDURE: LAPAROTOMY/LAPAROSCOPY, ADHESIOLYSIS, HERNIA REPAIR, BOWEL RESECTION (tumour, strangulated bowel, gallstone ileus). SIGMOID VOLVULUS: ENDOSCOPIC DETORSION (rigid/flexible sigmoidoscopy, rectal tube placement) → SUCCESSFUL (80%), then ELECTIVE SIGMOID COLECTOMY (high recurrence). EMERGENCY SURGERY if ischemia, perforation, peritonitis. INTUSSUSCEPTION (paediatric): AIR/ CONTRAST ENEMA (diagnostic, therapeutic). SURGERY if fails, peritonitis. Prognosis: SBO: mortality 3-5% (simple), 30% (strangulated). LBO: higher (malignancy, elderly). Zambian context: INTESTINAL OBSTRUCTION IS COMMON. ETIOLOGIES: ADHESIONS (increasing surgery), HERNIA (inguinal, femoral, neglected), VOLVULUS (sigmoid, endemic), TUMOUR (colorectal, advanced), INTUSSUSCEPTION (children). DIAGNOSIS: PLAIN X-RAY (available). CT (limited). SIGMOID VOLVULUS: plain film (coffee-bean), SIGMOIDOSCOPY (rigid/flexible) for detorsion + rectal tube. SURGERY: LAPAROTOMY, ADHESIOLYSIS, HERNIA REPAIR, BOWEL RESECTION, COLECTOMY available. FOCUS: RESUSCITATION, NGT, IDENTIFY STRANGULATION (urgent surgery), NON-OPERATIVE TRIAL (adhesions, partial), ENDOSCOPIC DETORSION (sigmoid volvulus), TIMELY SURGERY (complete obstruction, strangulation, failed non-operative).