It always starts with a sound…
A low, hollow gurgling echo drifting across the ward.
If you’ve been a surgeon long enough, you learn to recognise that sound, the one that tells you a bowel somewhere deep inside someone is unhappy. Distended. Struggling.
On this particular night, the call came just after midnight.
“Professor, could you come review this gentleman in Bed 12? Abdominal pain, distension… he looks a bit off.”
That phrase “a bit off” is usually the start of trouble.
The first look: a map of clues
When I walked in, he was lying curled slightly to the left, clutching his abdomen.
A faint grimace, the kind that comes with pain arriving in waves.
The smell of stale vomit lingered.
“Where does it hurt?”
“Everywhere… but mostly here,” he said, gesturing across his mid-abdomen.
His belly was distended, taut like a drum.
Peristalsis rippled visibly beneath the skin, almost like something alive trying to break free.
Classic.
Before labs, before scans, before anything electronic, the body had already whispered the diagnosis:
Small Bowel Obstruction.
How the bowel ends up in chaos
People imagine the bowel as a passive coil of pipework. It isn’t.
It’s a muscular, reactive, emotional organ, and when it meets an obstruction, it behaves like a motorway at rush hour when a lorry tips over.
Everything piles up behind it.
The causes fall into three archetypes, I always teach students to imagine three villains in this story:
The Puppeteer: something pulling or squeezing from the outside
Post-operative adhesions are the undisputed king here. The silent scar tissue from a surgery 20 years ago suddenly tightens, like a fishing line slowly reeling in a loop of bowel.
Then there are the hernias, trapping bowel at narrow gateways:
- inguinal
- femoral
- umbilical
- incisional
Each one is a potential prison.
These extrinsic causes don’t narrow the lumen; they drag the bowel into trouble.
The Builder: something thickening the bowel wall from within
Crohn’s disease loves this role. Decades of inflammation turn supple bowel into stiff, narrow tunnels.
Radiation scarring does the same. Tumours, too, both primary and metastatic.
These intramural villains make the bowel itself too rigid to pass anything through.
The Trespasser: something inside the lumen blocking the way
This is the classic “foreign body in the pipe” situation:
- Gallstone ileus (elderly, frail, and always when you least expect it)
- Bezoars
- Tumours growing inward
- Impacted food boluses
- Occasionally, parasites
Think of this category as literal objects sitting like boulders inside the intestinal road.
The orchestra of symptoms
Small bowel obstruction has a rhythm to it.
Pain starts colicky, sharp waves as peristalsis battles the obstruction.
Then nausea.
Then vomiting.
Then silence in the lower bowel, no flatus, no stool; the ultimate red flag.
The abdomen inflates like a balloon.
The bowel sounds change from sharp and tinkling…
…to sluggish and eventually silent.
You don’t need a CT to feel the tension in the room.
The danger that lurks beneath
While most obstructions can be treated conservatively, one thing changes the entire trajectory:
Strangulation.
When the blood supply is compromised, the bowel wall becomes ischaemic; dying from the inside out.
The pain becomes constant and severe.
The pulse quickens.
Lactate creeps up.
And sometimes, bruising appears along the flanks, the sinister mark of local bleeding.
Strangulation doesn’t negotiate.
It demands theatre, now.
Back to our patient…
His vitals were holding.
Tender but not peritonitic.
X-ray showed classic dilated loops, with valvulae conniventes marching all the way across, the ladder pattern every student learns.
CT later confirmed it: adhesional SBO.
We placed a large-bore NG tube, the hiss of escaping gas and pooled fluid is one of the most relieving sounds in surgery.
Relief washed over his face within minutes.
And then the next sound:
the NG output pouring into the canister like a waterfall.
Almost a litre in half an hour.
He slept for the first time that night.
The art of management; patience with precision
Small bowel obstruction isn’t a disease you “fix” immediately.
You watch it.
You listen to it.
You track every drop of fluid in and out.
“Drip and suck”, it’s what generations of surgeons have called the method:
- Fluid resuscitation
- NG decompression
- Electrolyte correction
- Careful observation
If the belly softens, the pain eases, and the bowels begin to whisper instead of scream, victory is near.
If not?
You prepare for theatre.
He recovered.
By morning, his distension eased.
His pain settled.
He passed a small volcanic eruption of flatus, the surgical equivalent of angels singing.
His bowels were waking up.
No knife was needed this time.
But each case reminds me: this condition is not gentle.
It can turn, without warning, from a simple blockage to a fatal strangulation.
The essence of SBO in one narrative line
“A gut in distress, battling against a blockade, and you, standing between it and catastrophe.”