Volvulus (Sigmoid and Caecal)
Summary
Volvulus is the twisting of a segment of bowel around its mesentery, leading to closed-loop bowel obstruction and potential vascular compromise (ischaemia, gangrene, perforation). Sigmoid volvulus is the most common type (~80%), typically occurring in elderly, debilitated patients with chronic constipation. Caecal volvulus (~20%) occurs in younger patients with a congenitally mobile caecum. Diagnosis is often clinical and radiological – the "Coffee Bean" sign on abdominal X-ray is classic for sigmoid volvulus. Management of sigmoid volvulus is primarily endoscopic derotation (flexible sigmoidoscopy) followed by elective resection to prevent recurrence. Caecal volvulus usually requires surgical resection (right hemicolectomy) as endoscopic derotation is often unsuccessful. Emergency surgery is required if there are signs of ischaemia, gangrene, or perforation. [1,2]
Clinical Pearls
"Coffee Bean" Sign: Classic AXR finding in Sigmoid Volvulus – Massively distended sigmoid loop rising out of the pelvis towards the right upper quadrant, resembling a coffee bean.
Sigmoid = Endoscopy First, Caecal = Surgery: Non-gangrenous sigmoid volvulus is treated with endoscopic derotation as initial management. Caecal volvulus almost always requires surgery.
Recurrence After Derotation is High (40-70%): Patients who have endoscopic derotation for sigmoid volvulus should be considered for elective sigmoid resection to prevent recurrence.
Look for Underlying Causes: Chronic constipation, high-fibre diet, neuropsychiatric conditions (institutionalised patients), Chagas disease (South America).
Demographics
| Type | Age | Sex | Population |
|---|---|---|---|
| Sigmoid Volvulus | Elderly (60-80 years) | Male > Female | Nursing homes, Psychiatric facilities, Chronic constipation, High-fibre diet areas (Africa, Asia). |
| Caecal Volvulus | Younger (30-60 years) | Female > Male | Congenitally mobile caecum (incomplete fixation). |
Incidence
- Sigmoid Volvulus: 80% of colonic volvulus. 3rd most common cause of Large Bowel Obstruction (after cancer and diverticulitis). Endemic in Africa, South America (high-fibre diet, Chagas).
- Caecal Volvulus: 10-20% of colonic volvulus.
Risk Factors
| Sigmoid Volvulus | Caecal Volvulus |
|---|---|
| Chronic constipation | Congenitally mobile caecum |
| High-residue/High-fibre diet | Previous abdominal surgery (adhesions) |
| Institutionalisation (Psychiatric, Nursing home) | Pregnancy |
| Neuropsychiatric disease (Parkinson's, Dementia) | Marathon running |
| Chagas disease (Megacolon) | Adhesions |
| Hirschsprung's disease |
Mechanism
- Redundant Bowel + Long Mesentery: Either sigmoid colon (naturally long mesentery) or caecum (if incompletely fixed to retroperitoneum).
- Twisting: Bowel loop twists around its mesenteric axis.
- Closed-Loop Obstruction: Bowel proximal and distal to the twist is obstructed. Massive distension of the twisted loop.
- Venous Obstruction: Twist compresses mesenteric veins first → Venous congestion → Oedema → Haemorrhagic infarction.
- Arterial Obstruction: If twist tight enough → Arterial occlusion → Ischaemia → Gangrene.
- Perforation: Necrotic bowel ruptures → Faecal peritonitis → Sepsis → Death.
Types of Caecal Volvulus
| Type | Description |
|---|---|
| Caecal Volvulus (Axial Twist) | Caecum and Terminal Ileum twist together. Most common. |
| Caecal Bascule | Caecum folds anteriorly and superiorly (without axial twist). Less common. |
| Condition | Key Features |
|---|---|
| Sigmoid Volvulus | Elderly, Constipated. Massive abdominal distension. Coffee Bean sign on AXR. |
| Caecal Volvulus | Younger. Dilated caecum in LUQ. "Embryo in fetu" sign. |
| Large Bowel Obstruction (Cancer/Stricture) | Gradual onset. Cancer = Left-sided, Apple Core on Barium. Stricture = Previous diverticulitis, Crohn's. |
| Pseudo-Obstruction (Ogilvie's Syndrome) | Massive colonic dilatation WITHOUT mechanical obstruction. Ill, hospitalised patients. No transition point on CT. |
| Small Bowel Obstruction | Central dilated loops. Vomiting early. Valvulae conniventes. |
| Toxic Megacolon | Acute colitis (C. diff, UC). Systemic toxicity. Fever, Tachycardia. Colonic dilatation (>6cm). |
Symptoms
| Symptom | Notes |
|---|---|
| Abdominal Pain | Colicky, Cramping. May become constant if ischaemia. |
| Abdominal Distension | Rapid onset, Massive. Hallmark of volvulus. |
| Absolute Constipation | No passage of faeces or flatus. |
| Vomiting | Late feature in large bowel obstruction (unlike SBO). |
| History of Constipation | Often chronic. Previous episodes of similar symptoms that resolved. |
Signs
| Sign | Notes |
|---|---|
| Massive Abdominal Distension | Classic. Asymmetric (sigmoid distends left → RUQ). |
| Tympanic Abdomen | Resonant on percussion. |
| Tenderness | Mild, generalised. Localised tenderness or Peritonism = Ischaemia/Gangrene. |
| Bowel Sounds | High-pitched tinkling early. Absent later (ileus, ischaemia). |
| Signs of Shock | Tachycardia, Hypotension, Fever (if perforation). |
| Empty Rectum on PR | DRE shows empty rectal vault. |
Blood Tests
| Test | Findings |
|---|---|
| FBC | Leucocytosis (Ischaemia, Infection). |
| U&E | Dehydration. AKI. |
| Lactate | Elevated = Ischaemia. Urgent surgery required. |
| ABG | Metabolic Acidosis (if ischaemia/shock). |
| Group & Save / Crossmatch | For potential surgery. |
Imaging
| Imaging | Findings |
|---|---|
| Abdominal X-ray (AXR) | Sigmoid Volvulus: "Coffee Bean" sign – Massively dilated loop arising from pelvis, pointing to RUQ. Loss of haustrations. Apex pointing to RUQ (opposite to origin). Caecal Volvulus: "Comma" or "Embryo in fetu" sign – Dilated caecum in LUQ/Central abdomen (displaced from RIF). |
| CT Abdomen (Gold Standard) | Confirms diagnosis. "Whirl Sign" (twisted mesentery and vessels). Identifies transition point. Assesses for ischaemia (Bowel wall thickening, Non-enhancement, Pneumatosis, Portal venous gas). |
Classic X-Ray Signs
| Sign | Type | Description |
|---|---|---|
| Coffee Bean Sign | Sigmoid Volvulus | Massively dilated sigmoid loop pointing to RUQ. |
| Frimann-Dahl Sign | Sigmoid Volvulus | Three lines converge towards twisted segment (inferior). |
| Kidney/Embryo Sign | Caecal Volvulus | Dilated caecum in ectopic position (LUQ). |
Management Algorithm
SUSPECTED VOLVULUS
(Massive Distension + Colicky Pain + Constipation)
↓
RESUSCITATION
- IV Access, Fluids
- NG Tube (if vomiting)
- Urinary Catheter
- NBM
- Bloods (FBC, U&E, Lactate, G&S)
↓
IMAGING: AXR +/- CT ABDOMEN
↓
ASSESS FOR PERITONITIS/ISCHAEMIA:
(Localised Tenderness, Peritonism, Shock, Elevated Lactate)
┌────────────────┴────────────────┐
YES NO
↓ ↓
EMERGENCY SURGERY IDENTIFY TYPE
(Laparotomy) (Sigmoid vs Caecal)
- Resection ↓
- Hartmann's (if unstable) ┌─────────────────────┐
- Primary Anastomosis │ SIGMOID │
(if viable + stable) │ │
│ ENDOSCOPIC │
│ DEROTATION │
│ (Flexible Sigmoid- │
│ oscopy + Flatus │
│ Tube) │
│ ↓ │
│ SUCCESSFUL? │
│ ┌───────┴───────┐ │
│ YES NO │
│ ↓ ↓ │
│ ELECTIVE URGENT │
│ SIGMOID SURGERY│
│ COLECTOMY │
│ (Prevent recurrence)│
└─────────────────────┘
↓
┌─────────────────────┐
│ CAECAL │
│ │
│ SURGERY │
│ (Right Hemi- │
│ colectomy) │
│ - Endoscopic │
│ derotation rarely│
│ works for caecal │
└─────────────────────┘
Sigmoid Volvulus Management
| Scenario | Management |
|---|---|
| Non-Gangrenous (No Peritonitis) | Endoscopic Derotation (Flexible Sigmoidoscopy + Flatus Tube). Successful in 70-90%. Then Elective Sigmoid Colectomy to prevent recurrence (40-70% recurrence if not resected). |
| Gangrenous / Peritonitis | Emergency Laparotomy. Hartmann's Procedure (Sigmoid resection + End colostomy + Rectal stump closure) – often safest in unstable patient. Primary anastomosis avoided if grossly contaminated. |
| Failed Endoscopic Derotation | Urgent surgery. |
Caecal Volvulus Management
| Scenario | Management |
|---|---|
| All Cases | Surgery – Right Hemicolectomy (Ileocolic resection). Endoscopic derotation rarely successful for caecal volvulus (differs from sigmoid). Cecopexy (fixing caecum to abdominal wall) has high recurrence, not recommended. |
| Complication | Notes |
|---|---|
| Bowel Ischaemia / Gangrene | If volvulus not derotated. Requires resection. |
| Perforation | Faecal peritonitis. High mortality. |
| Sepsis / Septic Shock | From translocation and perforation. |
| Recurrence | High for sigmoid volvulus after derotation alone (40-70%). Elective resection recommended. |
| Anastomotic Leak | Post-operative complication. |
| Stoma Complications | If Hartmann's performed. |
- Sigmoid Volvulus (Non-Gangrenous): Excellent prognosis with endoscopic derotation + elective resection.
- Gangrenous Volvulus: Mortality 30-50% (higher in elderly, delayed presentation).
- Caecal Volvulus: Good prognosis with surgical resection. Mortality higher if ischaemia (up to 20-30%).
Key Guidelines
| Guideline | Organisation | Key Recommendations |
|---|---|---|
| ASCRS Guidelines | American Society of Colon and Rectal Surgeons | Sigmoid: Endoscopic derotation, then elective resection. Caecal: Surgical resection. |
| ACPGBI Guidelines | Association of Coloproctology of GB & Ireland | Similar recommendations. Emergency resection for ischaemia. |
What is a Volvulus?
A volvulus is when a part of your bowel twists around itself, like a twisted balloon. This blocks the bowel and can cut off the blood supply to that part.
Is it serious?
Yes, if not treated quickly. If the blood supply is cut off, the bowel can die (gangrene) and burst, which is a life-threatening emergency.
How is it treated?
For sigmoid volvulus (the most common type), we can often untwist it using a camera (flexible sigmoidoscopy). If successful, we will advise surgery to remove that part of the bowel to prevent it happening again. For caecal volvulus, surgery is usually needed.
What if surgery is needed?
We remove the twisted section of bowel. Depending on the situation, we may reconnect the bowel straight away, or you may need a temporary bag (stoma) on your tummy while things heal.
Primary Sources
- Halabi WJ, et al. Sigmoid volvulus: demographics, etiology, and outcomes in the United States. Am J Surg. 2015;209(5):841-6. PMID: 25742359.
- American Society of Colon and Rectal Surgeons. ASCRS Clinical Practice Guidelines for the Management of Colon Volvulus. Dis Colon Rectum. 2017.
Common Exam Questions
- Classic X-Ray Finding (Sigmoid): "Describe the classic AXR finding in Sigmoid Volvulus."
- Answer: "Coffee Bean" Sign – Massively dilated sigmoid loop arising from the pelvis, pointing towards the Right Upper Quadrant.
- Initial Management (Sigmoid): "First-line management for non-gangrenous Sigmoid Volvulus?"
- Answer: Endoscopic Derotation (Flexible Sigmoidoscopy with Flatus Tube insertion).
- Caecal Volvulus Management: "Why is endoscopic derotation not effective for Caecal Volvulus?"
- Answer: Caecal volvulus is located proximal to the reach of a sigmoidoscope, and even colonoscopic derotation has low success rates. Surgery (Right Hemicolectomy) is required.
- Recurrence Prevention: "After successful endoscopic derotation for sigmoid volvulus, what should be considered?"
- Answer: Elective Sigmoid Colectomy to prevent recurrence (40-70% recurrence rate without resection).
Viva Points
- Whirl Sign: CT finding of twisted mesentery in volvulus.
- Hartmann's vs Primary Anastomosis: Discuss decision-making based on patient stability and bowel viability.
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