Interruption of the normal flow of intestinal content, due to mechanical obstruction (at small or large bowel level), or due to functional paralysis.
Causes
- Small bowel mechanical obstruction: tumours, adhesions from previous surgeries or infections
- Large bowel obstructions: tumours, volvolus, adhesions, inflammatory strictures (e.g. diverticulosis, etc.)
Clinical features
- Small bowel obstruction: cramping abdominal pain, nausea, vomiting, abdominal distention. Due to the
accumulation of fuids into the dilated intestinal loops, there is usually a varying degree of dehydration - Large bowel obstruction: bloating, abdominal pain, constipation, vomiting and nausea less frequent and
mainly in proximal colon obstruction; signs of dehydration and shock come later.
Investigations
- Abdominal X-ray (erect or left lateral decubitus, for airfluid level)
Differential diagnosis
- Paralytic ileus (diffuse functional paralysis of small and large bowel due to drugs, biochemical abnormalities,
abdominal infections etc)
MANAGEMENT
Pre-operative management
- IV fluids (normal saline, Ringer’s Lactate)
- To correct fluids deficit and replace ongoing losses plus maintenance fluids
- Monitor haemodynamic status (pulse, blood pressure, skin turgor, level of consciousness,
hydration of mucosae, urine output at least 0.5–1.0 ml/kg/hour) - It may take up to 6 hours to re-hydrate
- If not responding to IV fluids, suspect septic shock
- Insert urinary catheter to monitor urinary output
- Nasogastric tube decompression
- Pass NGT and connect with a drainage bag to empty the stomach in small bowel obstruction or
when clinically indicated - Nil by mouth
- Pass NGT and connect with a drainage bag to empty the stomach in small bowel obstruction or
- Give appropriate antibiotics
- Ceftriaxone 2 g IV once a day
- Plus metronidazole 500 mg IV every 8 hours
- If the patient is in severe colicky pain, administer pethidine 50-100 mg IV or IM
- If surgery is indicated and the patient’s parameters are near normal after resuscitation,
take the patient to the operating theatre for an appropriate surgical relief of the obstruction
Intra-operative fluid therapy
- Blood loss, fluid aspirated from the gut and other fluid losses must be replaced
- Maintenance fluid should be given: 5 ml/kg/hour Post-operative fluid therapy
- Replace all fluid losses
- Maintenance fluid
- Use normal saline or Ringer’s lactate solution and 5% dextrose in the ratio 1:2 for the first 24-48
hours post-operatively - Monitor for adequate rehydration
Post-operative antibiotics and analgesics
- Continue with analgesics in the postoperative period. (Tramadol, pethidine, diclofenac,
paracetamol; morphine may be used) - Continue with antibiotic treatment where clinically indicated (metronidazole +
ceftriaxone +/- gentamycin)
In selective cases, non-operative treatment of intestinal obstruction (in particular small bowel
obstructions) can be tried
- Indicated in appendicular mass, acute pyosalpingitis (PID), some patients with adheisions, pseudo obstruction, plastic peritonitis of TB, acute pancreatitis
- Involves NGT decompression, intravenous fluid therapy and antibiotic therapy if indicated
- Monitor clinical progression of obstruction using parameters of: abdominal pain, abdominal girth,
amount and colour of NG aspirate, temperature, pulse - If no improvement after 72 hours or the NG content becomes fecolent, operate the patient