01OverviewDefinition, clinical context and the essential points that orientate the chapter.
Caecal volvulus arises when an abnormally mobile caecum and adjoining right colon rotate, commonly involving the terminal ileum and mesentery. Inadequate congenital fixation provides a substrate, while postoperative anatomical change or adhesions may contribute in some patients. The caecum can move far from its usual right iliac position, so the point of greatest distension or pain does not reliably locate the origin of the bowel loop. The illness often presents more acutely than sigmoid volvulus and can affect younger adults, although neither age nor sex safely rules it in or out.
Caecal bascule is a related configuration in which the caecum folds forward and upward over the ascending colon, obstructing emptying without the classic axial torsion. That distinction explains why a mesenteric whirl may be absent; it does not justify treating the patient as having functional dilatation. Distension and pressure can still impair bowel integrity. Management of symptomatic bascule follows the same broad operative principles as other caecal volvulus. The crucial contrast with sigmoid disease is practical: the twisted caecum is not usually amenable to reliable endoscopic decompression, so a sequence of attempted colonoscopies can postpone the effective treatment.
Key points
- Caecal volvulus usually requires urgent surgery; colonoscopic detorsion has low success and can delay treatment or perforate the bowel.
- A displaced distended caecum with a transition and mesenteric twist on CT identifies a mechanical problem, even when the small bowel is also dilated.
- Peritonitis, deteriorating perfusion or reduced bowel enhancement requires immediate assessment for infarction and operative source control.
- Segmental resection is preferred; decide between anastomosis and an end stoma using viability, contamination and the patient’s physiological condition.
- Caecal bascule is a folding variant without the usual axial twist; absence of a whirl sign does not make its mechanical obstruction harmless.
- Nonresectional fixation is a selected option for viable bowel in a patient unfit for resection, with recurrence and complication risks clearly explained.
02AetiologyUnderlying causes, associations and risk factors, with why each one matters.
Mobile right colon
Failure of normal fixation can leave the caecum and ascending colon unusually mobile. Rotation or folding of this mobile segment can then obstruct intestinal transit.
Acquired anatomical contributors
Previous operations and adhesions may change bowel mobility or create a pivot around which a mobile segment turns. The clinical history raises suspicion but does not establish the configuration.
03PathophysiologyThe causal sequence from the underlying abnormality to symptoms and harm.
- 1Axial torsion
Rotation of the caecum and associated mesentery blocks the lumen and may involve the terminal ileum. Venous and arterial compromise can accompany the mechanical obstruction.
- 2Caecal bascule
The caecum folds anteriorly and superiorly over the ascending colon without the usual axial twist. Impaired emptying then causes progressive dilatation despite absence of a classic mesenteric whirl.
- 3Pressure and tissue failure
Continuing distension increases wall stress and may impair perfusion. A folded or twisted caecum can progress to necrosis, perforation and widespread peritoneal contamination.
04Clinical features and red flagsSymptoms, examination findings, patterns of presentation and time-critical warnings.
Pain, vomiting, distension and reduced stool or flatus passage are typical but variable. A history of intermittent similar pain may reflect previous transient torsion. Persistent symptoms now require structural assessment; a previous spontaneous recovery does not establish that another episode will resolve safely.
The largest loop may project centrally or into the left upper abdomen, and the right iliac fossa can appear relatively empty. These findings can resemble sigmoid volvulus on a plain film. Use CT to trace the displaced bowel and identify the actual transition rather than naming the loop from its location alone.
Progressive focal tenderness, guarding, fever, tachycardia or shock raises concern for gangrene or perforation. Reduced enhancement, free gas or concerning fluid on CT adds weight. Do not wait for all of these features to coexist before involving the operating surgeon.
A patient who has recently undergone unrelated surgery may be labelled as having ileus or ACPO. A displaced caecum and focal transition instead suggest a mechanical configuration. Review the actual imaging before prescribing a prokinetic or accepting prolonged conservative care.
Assess dehydration, renal dysfunction, nutrition and cardiopulmonary reserve alongside the current obstruction. Operative source control may be necessary even in a high-risk patient; the risk assessment helps choose reconstruction, critical-care support and the limits of treatment rather than simply postponing a decision.
05InvestigationsWhat to request, why it matters and how to interpret it.
Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.
- 01
Contrast-enhanced CT abdomen and pelvisFirst step - Why
- Locate the caecum, define the obstruction and assess threatened bowel.
- Interpretation and limitations
- Trace the terminal ileum, caecum and ascending colon on multiple planes. Axial volvulus may show a twisted mesentery and converging bowel, whereas bascule produces a folded configuration. Check distal collapse, proximal small bowel, enhancement and free gas; a missing whirl does not exclude bascule.
- 02
Plain abdominal imaging when immediately informative - Why
- Identify a distended displaced loop while arranging definitive clarification.
- Interpretation and limitations
- A large haustrated loop can resemble the coffee-bean appearance of sigmoid volvulus, and a film can be nondiagnostic. The visible configuration may prompt urgency, but cannot reliably establish perfusion or justify endoscopic treatment on the assumption that the sigmoid is involved.
- 03
Serial observations, blood gas and lactate - Why
- Measure physiological consequences and detect deterioration during preparation for treatment.
- Interpretation and limitations
- Use haemodynamics, mentation, urine output and repeated abdominal examination with biochemical data. Elevated lactate supports concern for hypoperfusion, but a normal measurement cannot exclude segmental bowel injury. Reassessment should have a responsible clinician and an interval appropriate to the patient’s instability.
- 04
Renal profile, blood count and operative preparation - Why
- Identify fluid deficits, electrolyte abnormalities and perioperative support needs.
- Interpretation and limitations
- Renal dysfunction may follow vomiting and sequestration or predate the event. Correct significant abnormalities while organising treatment rather than using complete biochemical normalisation as a prerequisite for source control. Check haemoglobin and blood availability when a resection is anticipated.
06Differential diagnosisRealistic alternatives and the features that help distinguish them.
Sigmoid volvulus
A large gas-filled loop can look similar on a plain film. CT identification of the loop’s origin matters because sigmoid and caecal volvulus usually require different initial interventions.
Acute colonic pseudo-obstruction
Acutely dilated colon after illness or surgery may be functional. A displaced caecum with a structural transition or twist instead indicates mechanical obstruction.
Distal obstructing cancer
A colonic tumour can enlarge the caecum upstream without primary caecal twisting. Imaging must distinguish the downstream lesion from a caecal transition to guide source control.
07ManagementImmediate care, first-line treatment, alternatives and escalation.
01Urgent operative pathwayAvoid an ineffective decompression sequenceFirst stepImaging or operative assessment identifies symptomatic caecal volvulus or bascule.+
- 1Contact the emergency surgical team, maintain nil-by-mouth care and begin resuscitation. Peritonitis, suspected necrosis or perforation calls for urgent source control, with appropriate intravenous antibiotics when contamination or sepsis is suspected.
- 2Prepare for surgery rather than routinely attempting colonoscopic detorsion. The caecal location, low success of endoscopy and risk of perforation make the sigmoid endoscopic pathway unsuitable.
- 3At operation, inspect the involved caecum, terminal ileum, mesentery and remaining colon. Resect the affected segment, ensuring that nonviable bowel is removed and the remaining ends have adequate perfusion.
- 4Choose primary anastomosis when the patient and tissues support it. In profound physiological derangement, heavy contamination or doubtful remaining viability, an end stoma or staged reconstruction may offer a safer course.
02Worked caseDisplaced caecum treated definitivelyA 58-year-old develops abrupt pain, vomiting and distension after earlier intermittent similar episodes.+
- 1She is tachycardic but responds to initial fluid treatment and has no generalised guarding. CT shows a caecum displaced into the upper left abdomen, twisted ileocolic mesentery, distal colonic collapse and dilated terminal ileum.
- 2The team identifies caecal volvulus rather than sigmoid volvulus or ACPO. Surgical consent covers right-sided resection, anastomosis if appropriate and a possible stoma; a routine colonoscopic reduction is not attempted.
- 3At urgent surgery the caecum is congested but the bowel remaining after resection is well perfused. There is no perforation or faecal contamination, and the patient’s circulation remains stable.
- 4A right colectomy with ileocolic anastomosis removes the mobile affected segment. Postoperative observations, urine output and abdominal assessment improve, with gradual return of bowel function and oral intake.
- 5At surgical follow-up she reports no further episodic obstruction and has regained her baseline activity. The operation both relieved the acute event and removed the anatomy responsible for recurrent twisting; advice covers postoperative warning symptoms and the possibility of altered bowel habit.
03High-risk operative decisionWhen viable bowel and severe frailty coexistDefinitiveThe surgeon must balance definitive resection against an unusually high operative burden.+
- 1Establish whether the bowel is genuinely viable; a nonresectional strategy cannot leave a gangrenous segment in place. Consider the patient’s wishes, physiological reserve and the likely consequences of recurrent obstruction.
- 2In a patient judged unfit for resection, selected detorsion with fixation may be considered by an experienced surgeon. Explain that evidence is limited and recurrence is more frequent than after resection; caecostomy has important leakage and morbidity concerns.
- 3Document why the selected operation is proportionate, what was found and how recurrence or postoperative deterioration will be managed. A less extensive procedure still needs active observation and a realistic follow-up plan.
08ComplicationsImportant consequences, why they occur and why they matter clinically.
Nonviable bowel
Mesenteric compromise or sustained pressure can produce caecal infarction. The need to remove affected bowel is not negated by normal early blood markers.
Peritoneal contamination
Perforation can cause rapidly progressive sepsis and shock. The operation must remove nonviable tissue and control contamination while reconstruction reflects the patient’s condition.
Recurrent torsion
Leaving a mobile segment after detorsion or fixation can permit another episode. That recurrent mechanical risk is a major reason resection is generally preferred when the patient can tolerate it.
09Monitoring and follow-upTreatment response, safety checks and longer-term review.
- Before operation, reassess pain, perfusion and abdominal signs during resuscitation and transfer. Increasing tenderness or instability must be communicated directly rather than left for the next routine ward round.
- After anastomosis, investigate persistent tachycardia, new pain, fever or organ dysfunction in the context of leak, residual ischaemia and other postoperative complications. Expected ileus should be a considered diagnosis, not an automatic label.
- If an ileostomy is formed, monitor its viability, output and the patient’s fluid balance and renal function. Give the patient a specific route for help with excessive losses, low urine output or inability to maintain intake.
- At recovery review, assess nutrition, mobility and bowel habit, explaining the operation that was performed and any future reconstruction decision. Document the residual anatomy and whether pathology identified an unexpected additional process.
10Special situationsVariants, exceptions and circumstances that change the usual approach.
Bascule can still deteriorate
The absence of axial mesenteric rotation distinguishes a bascule anatomically, but the folded bowel remains obstructed. Continued expansion can lead to ischaemia, necrosis and perforation. A report that lacks a whirl sign should therefore lead to careful anatomical review, not reassurance that all caecal dilatation is functional.
Evidence behind the endoscopy warning
The ASCRS recommendation against routine caecal endoscopic reduction reflects low success in small retrospective series and the consequences of delay and perforation. It is a location-specific decision. A published exceptional endoscopic success in a highly selected patient does not establish the routine pathway for a new acute presentation.
Do not equate colour with recovery
Congestion and viability must be assessed by the operating surgeon in the context of perfusion and the whole segment. Resection is generally preferred even when bowel is viable because it addresses recurrence. The question of anastomosis concerns the remaining tissue and patient, rather than simply whether one portion looked less dark after handling.
Communicate the precise operation
“Volvulus surgery” is not a sufficient handover. State which bowel was resected, the anastomosis or stoma configuration, contamination, any concern about residual perfusion and the postoperative support plan. These details determine how new pain, high output or delayed recovery should be interpreted.
11Common pitfallsFrequent interpretation and management errors.
- 01
Mistaking an upper-left abdominal gas loop for sigmoid disease can lead to inappropriate detorsion attempts; trace its continuity with the terminal ileum and ascending colon.
- 02
Assuming postoperative distension is functional without reviewing the transition point risks giving neostigmine to a patient with a mechanical obstruction.
- 03
Planning fixation for bowel that is nonviable confuses recurrence prevention with removal of an infarcted source; the latter requires resection.
- 04
Choosing an anastomosis solely because a right colectomy was performed ignores contamination, shock and the quality of the remaining bowel.