Sigmoid volvulus is a closed-loop large bowel obstruction caused by torsion of a redundant sigmoid colon around its mesenteric axis, accounting for 60–75% of all colonic volvulus and ~10–15% of large bowel obstructions in the US. [1-2] It predominantly affects elderly men (6th–8th decade) with neuropsychiatric disorders, chronic constipation, and institutional residence. [1-3] Mortality exceeds 50% when bowel gangrene develops, making rapid recognition and management critical. [4]
1. History
- Classic triad: Constipation/obstipation, progressive abdominal distension, and abdominal pain [1][4]
- Onset may be insidious (hours to days); sigmoid volvulus often has a more indolent presentation than cecal volvulus [1]
- Nausea and vomiting (may be late findings)
- Prior episodes of similar symptoms with spontaneous resolution (suggests intermittent volvulus)
- Baseline bowel habits — chronic constipation, laxative dependence
- History of neuropsychiatric disease (dementia, Parkinson's, schizophrenia), institutionalization, or bedbound status [1-2]
- Important negatives: Fever, bloody stool, recent surgery, prior abdominal operations
2. Alarm Features
- Hemodynamic instability (tachycardia, hypotension) — suggests ischemia/perforation [1]
- Peritoneal signs (guarding, rigidity, rebound tenderness) — mandate emergent surgery, NOT endoscopic detorsion [1-2]
- Fever with leukocytosis and elevated lactate — bowel ischemia or necrosis [3][5]
- Pneumoperitoneum on imaging — perforation [1]
- Pneumatosis intestinalis on CT [1]
- Symptom duration >24 hours associated with higher incidence of intestinal necrosis [6]
- Emergency presentation with peritonitis or shock occurs in up to 25% of sigmoid volvulus cases [1]
3. Medications
- Contributors to volvulus:
- Anticholinergics, opioids, antipsychotics, calcium channel blockers — all promote constipation and colonic dysmotility [2]
- Chronic laxative use (paradoxically, laxative users may have better outcomes with endoscopic detorsion) [2]
- Acute management medications:
- IV fluid resuscitation and electrolyte correction
- Broad-spectrum antibiotics if peritonitis, ischemia, or perforation suspected
- Avoid prokinetics as primary treatment (unlike ACPO, neostigmine is not indicated)
- Contraindicated: Oral contrast or oral medications in the setting of complete obstruction
4. Diet
- NPO on presentation — essential for potential procedural or surgical intervention
- Post-detorsion: Advance diet slowly as tolerated once bowel function returns
- Long-term: High-fiber diet and adequate hydration to prevent chronic constipation and recurrence
- Avoid constipating foods in patients with known redundant sigmoid colon
5. Review of Systems
- GI: Last bowel movement, last flatus, nausea/vomiting, bloody stool, melena
- Constitutional: Fever, weight loss (consider malignancy as alternative cause of obstruction)
- Cardiovascular: Chest pain, palpitations (assess for dehydration-related arrhythmia)
- Urologic: Decreased urine output (dehydration, AKI from third-spacing/emesis) [1]
- Neuropsychiatric: Cognitive status, psychiatric medications, mobility
6. Collateral History and Family History
- Collateral is critical — many patients have neuropsychiatric disorders or reside in long-term care facilities and may be unable to provide accurate history [1]
- Caregivers should be asked about baseline bowel habits, last known normal stool, medication changes, prior episodes
- Family history is generally not a major contributor, though anatomic predisposition (long redundant colon) may have a familial component
- Social context: Institutionalization, immobility, dietary habits
7. Risk Factors
- Age >70 years (in Western countries) [1-2]
- Male sex (2:1 predominance in the US) [3]
- Neuropsychiatric disorders: Dementia, Parkinson's disease, schizophrenia, developmental delay [1-2]
- Chronic constipation and colonic dysmotility [2]
- Anatomic: Long, redundant sigmoid colon with narrow mesenteric attachment [2-3]
- Institutionalization and bedbound status [1]
- Prior abdominal surgery [2]
- Diabetes mellitus [2]
- African American race (in the US) [2]
- High-altitude residence and high-fiber diet (in the "volvulus belt" — Africa, Middle East, South Asia) [1][3]
8. Differential Diagnosis
- Obstructing colorectal cancer — most common cause of LBO overall; CT differentiates [1]
- Cecal volvulus — younger patients, female predominance; different management (surgery preferred over endoscopy) [1][3]
- Acute colonic pseudo-obstruction (Ogilvie syndrome) — colonic dilatation without mechanical obstruction; CT shows no whirl sign [2]
- Diverticular stricture — chronic history, CT findings of diverticulosis with narrowing [1]
- Cecal bascule — cecum folds anteriorly without axial twist [1]
- Fecal impaction — can mimic on plain films; CT and rectal exam differentiate [4]
- Toxic megacolon — associated with IBD or C. difficile; systemic toxicity prominent
- Incarcerated hernia — physical exam and CT differentiate
9. Past Medical History
- Prior episodes of volvulus — recurrence rate is 43–75% after detorsion alone [1]
- Chronic constipation, megacolon, Chagas disease (in endemic areas)
- Neuropsychiatric diagnoses and associated medications
- Prior abdominal or pelvic surgery (adhesions)
- Comorbidities affecting surgical candidacy (ASA class, cardiac/pulmonary disease) [1]
10. Physical Exam
- Vital signs: Tachycardia and hypotension suggest ischemia/perforation/dehydration
- Abdomen: Markedly distended, tympanic to percussion, asymmetric distension possible
- Tenderness: Variable; peritoneal signs (guarding, rigidity, rebound) indicate complicated volvulus requiring emergent surgery [1]
- Digital rectal exam: Characteristically reveals an empty rectal vault [1]
- Bowel sounds: May be high-pitched early, absent late
- Assess for signs of dehydration and sepsis
11. Lab Studies
- CBC: Leukocytosis suggests ischemia or necrosis; elevated neutrophil ratio correlates with intestinal necrosis [6]
- BMP/CMP: Electrolyte derangements (hypokalemia, metabolic alkalosis from vomiting; metabolic acidosis if ischemic), AKI from dehydration [1]
- Lactate: Elevated lactate is associated with bowel ischemia and need for emergency surgery [3][5]
- CRP: Higher CRP levels are a predictor of need for emergency surgery [5]
- Coagulation profile: Baseline for potential surgical intervention [3]
- Type and screen: If surgery anticipated
- Blood gas: Assess for metabolic acidosis in critically ill patients
12. Imaging
- Plain abdominal radiograph (first-line):
- "Coffee bean" sign — large, ahaustral, dilated sigmoid loop projecting toward the upper abdomen with central radiopaque stripe pointing toward the LLQ [1][3]
- Diagnostic in 60–81% of sigmoid volvulus cases [1-2]
- Look for pneumoperitoneum (upright CXR) and pneumatosis [1]
- CT abdomen/pelvis (gold standard):
- "Whirl sign" — mesenteric vessels and bowel loops torsed around a central point [1]
- "Bird's beak" sign — tapered narrowing at the point of torsion [1]
- Near 100% sensitivity, >90% specificity [1-2]
- Identifies ischemia, perforation, pneumatosis, and alternative diagnoses [1]
- Volvulus rotation ≥360° and ischemia on CT predict need for emergency surgery [5]
- Water-soluble contrast enema: Rarely needed; shows "bird's beak" at obstruction point if CT unavailable [1]
- Imaging is unnecessary to delay when peritonitis is obvious — proceed directly to OR
13. Special Tests
- Flexible sigmoidoscopy: Both diagnostic and therapeutic — visualizes the classic mucosal pinwheel/spiral pattern at the point of torsion and assesses mucosal viability [1-3]
- Rigid proctoscopy: Alternative for detorsion, but flexible sigmoidoscopy provides better visualization [3]
- Predictors of endoscopic detorsion failure: Cecal diameter ≥6.8 cm, BMI <18.5, colonic dilatation ≥85 mm, younger age (≤65 years) [7-8]
- No validated clinical scoring system specific to sigmoid volvulus, though CT findings (rotation degree, ischemia, CRP, lactate) help stratify surgical urgency [5]
14. ECG
- ECG is not diagnostic for sigmoid volvulus but should be obtained in:
- Elderly patients with significant comorbidities (pre-procedural/pre-operative assessment)
- Patients with electrolyte derangements (hypokalemia, hypomagnesemia) — risk of arrhythmia
- Tachycardic or hemodynamically unstable patients to rule out cardiac etiology
- Watch for hypokalemia-related changes (U waves, flattened T waves, prolonged QT) from vomiting/dehydration
15. Assessment
Sigmoid volvulus is a surgical emergency that exists on a spectrum from uncomplicated (viable bowel, stable patient) to complicated (ischemia, gangrene, perforation, sepsis). Key clinical decision points:
- Uncomplicated: Hemodynamically stable, no peritonitis → endoscopic detorsion first [1-2]
- Complicated: Peritonitis, perforation, hemodynamic instability, failed detorsion → emergent surgery [1]
- Atypical presentations occur in patients with neuropsychiatric disorders who may not localize pain or communicate symptoms [1]
- Complications: Bowel ischemia/gangrene, perforation, sepsis, recurrence (43–75% without definitive surgery) [1]
16. Treatment Plan
Initial stabilization:
- IV access, aggressive fluid resuscitation, electrolyte correction
- NPO, nasogastric tube if significant vomiting or proximal dilation
- Broad-spectrum antibiotics if ischemia, perforation, or sepsis suspected
Uncomplicated sigmoid volvulus (stable, no peritonitis):
- Endoscopic detorsion via flexible sigmoidoscopy — first-line therapy, successful in 60–95% of cases [1-3]
- Place rectal decompression tube after successful detorsion to prevent immediate recurrence [1-3]
- Surgical consultation during index admission — strongly recommended by both ASCRS and ASGE [1-2]
- Sigmoid colectomy during the same hospitalization to prevent recurrence (ASCRS strong recommendation) [1]
Complicated sigmoid volvulus (peritonitis, perforation, failed detorsion):
- Emergent sigmoid resection [1]
- Hartmann procedure (end colostomy) preferred in high-risk patients (sepsis, acidosis, coagulopathy, high ASA class); mortality 5–7% [1]
- Primary anastomosis may be considered in stable, lower-risk patients; leak rate ~4.7%, mortality ~3.4% [1]
High-risk surgical patients:
17. Disposition
- All patients with sigmoid volvulus require admission — there is no role for ED discharge
- ICU admission: Hemodynamic instability, sepsis, post-emergent surgery, significant comorbidities
- Surgical floor: Post-successful detorsion awaiting semi-elective sigmoid colectomy
- Emergent surgical consultation triggers:
- Peritonitis or perforation [1-2]
- Failed endoscopic detorsion [1]
- Evidence of bowel ischemia on CT or endoscopy [1][5]
- Hemodynamic instability [1]
- Recurrent volvulus [2]
- Patients managed with detorsion alone (without colectomy) have 61% recurrence at a median of 31 days [1]
18. Follow Up / Return Precautions
- If colectomy performed during index admission: Routine post-surgical follow-up at 2–4 weeks
- If discharged after detorsion without colectomy (high-risk, non-operative candidates):
- Close outpatient follow-up within 1–2 weeks
- Aggressive bowel regimen (fiber, osmotic laxatives, adequate hydration)
- Return immediately for recurrent abdominal pain, distension, obstipation, vomiting, or fever
- Patient/caregiver counseling:
- Recurrence rate is 43–75% without definitive surgery [1]
- Each recurrence carries risk of ischemia, perforation, and death
- Emergency surgery for recurrent volvulus carries significantly higher mortality (13–62%) than elective surgery after initial episode (3.3–32%) [1]
- Expected recovery after elective sigmoid colectomy is generally favorable with low recurrence [1][10]
References
1. The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Management of Colonic Volvulus and Acute Colonic Pseudo-Obstruction. — Alavi K, Poylin V, Davids JS, et al. Diseases of the Colon and Rectum. 2021.
2. The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Management of Colonic Volvulus and Acute Colonic Pseudo-Obstruction. — Alavi K, Poylin V, Davids JS, et al. Diseases of the Colon and Rectum. 2021.
3. The American Society of Colon and Rectal Surgeons Clinical Practice Guidelines for the Management of Colonic Volvulus and Acute Colonic Pseudo-Obstruction. — Alavi K, Poylin V, Davids JS, et al. Diseases of the Colon and Rectum. 2021.
4. American Society for Gastrointestinal Endoscopy Guideline on the Role of Endoscopy in the Management of Acute Colonic Pseudo-Obstruction and Colonic Volvulus. — Naveed M, Jamil LH, Fujii-Lau LL, et al. Gastrointestinal Endoscopy. 2020.
5. American Society for Gastrointestinal Endoscopy Guideline on the Role of Endoscopy in the Management of Acute Colonic Pseudo-Obstruction and Colonic Volvulus. — Naveed M, Jamil LH, Fujii-Lau LL, et al. Gastrointestinal Endoscopy. 2020.
6. Gastrointestinal Surgical Emergencies Textbook. — Ashley E. Aaron, Andrea Amabile, Ciro Andolfi, et al American College of Surgeons (2021). 2021.
7. Gastrointestinal Surgical Emergencies Textbook. — Ashley E. Aaron, Andrea Amabile, Ciro Andolfi, et al American College of Surgeons (2021). 2021.
8. Sigmoid Volvulus in a Young Woman Nearly Misdiagnosed as Fecal Impaction. — Chang CJ, Hsieh TH, Tsai KC, Fan CM. The Journal of Emergency Medicine. 2013.
9. Sigmoid Volvulus in a Young Woman Nearly Misdiagnosed as Fecal Impaction. — Chang CJ, Hsieh TH, Tsai KC, Fan CM. The Journal of Emergency Medicine. 2013.
10. Optimizing Management of Sigmoid Volvulus: Predictors of Surgical Intervention and Early Recurrence. — Girgin T, Erozkan K, Basci F, et al. European Journal of Radiology. 2026.
11. Optimizing Management of Sigmoid Volvulus: Predictors of Surgical Intervention and Early Recurrence. — Girgin T, Erozkan K, Basci F, et al. European Journal of Radiology. 2026.
12. Analysis of Clinical Diagnosis and Treatment of Intestinal Volvulus. — Fo Y, Kang X, Tang Y, Zhao L. BMC Gastroenterology. 2023.
13. Analysis of Clinical Diagnosis and Treatment of Intestinal Volvulus. — Fo Y, Kang X, Tang Y, Zhao L. BMC Gastroenterology. 2023.
14. Two Decades of Endoscopic Detorsion in Sigmoid Volvulus: Prognostic Factors for Failure. — Tantinam T, Buakhrun S, Chandrachamnong P, et al. Surgical Endoscopy. 2025.
15. Two Decades of Endoscopic Detorsion in Sigmoid Volvulus: Prognostic Factors for Failure. — Tantinam T, Buakhrun S, Chandrachamnong P, et al. Surgical Endoscopy. 2025.
16. Clinical Factors Associated With Endoscopic Decompression Failure and Recurrent Sigmoid Volvulus: A Retrospective Cohort Study. — Choi S, Hyun HK, Park J, et al. Journal of Gastroenterology and Hepatology. 2026.
17. Clinical Factors Associated With Endoscopic Decompression Failure and Recurrent Sigmoid Volvulus: A Retrospective Cohort Study. — Choi S, Hyun HK, Park J, et al. Journal of Gastroenterology and Hepatology. 2026.
18. Endoscopic Management of Acute Sigmoid Volvulus in High Risk Surgical Elderly Patients: A Randomized Controlled Trial. — Negm S, Farag A, Shafiq A, Moursi A, Abdelghani AA. Langenbeck's Archives of Surgery. 2023.
19. Endoscopic Management of Acute Sigmoid Volvulus in High Risk Surgical Elderly Patients: A Randomized Controlled Trial. — Negm S, Farag A, Shafiq A, Moursi A, Abdelghani AA. Langenbeck's Archives of Surgery. 2023.
20. Diagnosis and Management of Colonic Volvulus. — Lai SH, Vogel JD. Diseases of the Colon and Rectum. 2021.
21. Diagnosis and Management of Colonic Volvulus. — Lai SH, Vogel JD. Diseases of the Colon and Rectum. 2021.