Treatment of Sigmoid Volvulus

Colonic volvulus, where part of the colon twists, is a significant cause of large bowel obstruction, representing 15% of cases, second only to cancer and diverticulitis. Acute sigmoid volvulus (SV), which affects the sigmoid colon, is the most common type, with morbidity rates ranging from 6% to 42% and mortality varying from 7% to 90%. The incidence of SV varies globally, being more common in regions such as Africa, Ethiopia, Australia, and East Asia, where it can account for up to 50% of bowel obstructions.

SV often presents as partial or complete obstruction and can lead to severe complications such as ischemia, necrosis, and perforation, especially in older patients. The primary treatment goals are relieving the obstruction, reducing pressure, and correcting the twist. According to the World Society of Emergency Surgery (WSES), endoscopic decompression is recommended for patients without infection, perforation, or hemodynamic instability. However, surgery is necessary if decompression fails, with options including sigmoidopexy, sigmoidectomy, or colostomy. Sigmoidopexy is less invasive but has a higher recurrence rate, while sigmoidectomy, though riskier, may reduce recurrence and improve long-term survival.

This retrospective study aims to compare the outcomes of sigmoidopexy and sigmoidectomy in patients with acute SV undergoing emergency surgery at West China Hospital, Sichuan University, over a 14-year period. The primary outcome is the recurrence rate of SV, with secondary outcomes including 30-day mortality and morbidity (complications).

Introduction:

Colonic volvulus, a significant cause of large bowel obstruction, occurs when a segment of the colon twists, obstructing normal bowel function. Among the different types of colonic volvulus, acute sigmoid volvulus (SV) is the most common, with a high incidence in certain regions, such as the "twist belt" in Africa, Ethiopia, East Asia, and Australia, where its frequency can exceed 50%. SV frequently presents as either partial or complete bowel obstruction, leading to ischemia, necrosis, and potential perforation if untreated. The morbidity and mortality associated with SV are substantial, particularly in elderly patients. Prompt management is crucial to reduce complications and improve patient outcomes.

Treatment Approaches:

The primary goal of treatment is to relieve the obstruction and address the twisted portion of the colon. The World Society of Emergency Surgery (WSES) recommends endoscopic decompression for patients without signs of severe infection, perforation, or hemodynamic instability. If decompression fails, or if necrosis is present, surgical intervention is necessary. Surgical options include sigmoidopexy, sigmoidectomy, mesenteroplasty, or colostomy. Sigmoidopexy is less invasive but carries a higher risk of recurrence, whereas sigmoidectomy, though more complex, may reduce recurrence and improve long-term survival.

Despite various treatment options, the optimal approach remains unclear due to inconsistencies in the existing literature. This study compares two commonly used surgical methods-sigmoidopexy and sigmoidectomy-to assess their outcomes in terms of SV recurrence, complications, and overall survival.

Methods:

This retrospective study reviewed patients who underwent emergency surgery for acute SV at West China Hospital, Sichuan University, between April 2009 and August 2023. The hospital, a major medical center in Chengdu, China, treats thousands of emergency cases annually. Ethical approval was obtained from the hospital's Ethics Review Board, and informed consent was waived due to the study's retrospective nature.

Inclusion Criteria:

Adults with acute symptoms of intestinal obstruction. Acute SV diagnosis confirmed by CT or surgery. First emergency surgery for acute SV at the hospital.

Exclusion Criteria:

Torsion of parts of the colon other than the sigmoid. Non-surgical management of acute SV or treatment at another institution. Conditions such as bowel perforation or unrelated obstructions. Patients unable to undergo surgery due to poor health.

Primary Outcome:

Recurrence rate of SV after sigmoidopexy or sigmoidectomy.

Secondary Outcomes:

30-day mortality and morbidity, assessed by the Clavien-Dindo classification of complications.

Data Collection:

Data were extracted from the hospital's medical records and supplemented by telephone follow-up with patients or their families. Information collected included:

Demographic details (age, gender, symptoms). Medical history (comorbidities, previous surgeries). ASA score, BMI, surgery details, and post-operative recovery. Surgical duration, hospital stay length, complications, and follow-up data.

Statistical Analysis:

Statistical analysis was conducted using R software (version 4.3.3). Continuous variables were assessed for normal distribution and expressed as means ± standard deviation or medians with ranges. Categorical variables were presented as percentages. For comparing continuous variables, Student's t-test or Mann-Whitney U test was used. For categorical data, Chi-square or Fisher's exact test was applied. A P-value of \< 0.05 was considered statistically significant.

Eligibility Criteria:
Inclusion Criteria:

1. Adult patients presenting with symptoms of acute intestinal obstruction.
2. Diagnosis of acute SV confirmed by the typical "whirl sign" on computed tomography (CT) or laparotomy.
3. First emergency surgery for acute SV performed at our institution.

Exclusion Criteria:

1. Torsion of intestinal segments other than the sigmoid.
2. Patients diagnosed with "acute SV" but treated conservatively or operated on at another hospital.
3. Concurrent conditions such as non-SV-related bowel perforation or obstruction.
4. Patients with severe overall states not amenable to surgery.