From the Guidelines
The top four risk factors for large bowel obstruction (LBO) are colorectal cancer, diverticular disease, volvulus, and fecal impaction. Colorectal cancer is the leading cause of LBO, accounting for approximately 50-60% of cases, as tumors gradually narrow the colonic lumen until complete obstruction occurs 1. Diverticular disease, particularly after episodes of diverticulitis, can lead to stricture formation and subsequent obstruction due to inflammation and scarring of the bowel wall. Volvulus, most commonly affecting the sigmoid colon in elderly patients and the cecum in younger individuals, involves twisting of the bowel around its mesenteric axis, causing both obstruction and potential ischemia. Fecal impaction predominantly affects elderly, immobile, or neurologically impaired patients, and occurs when hardened stool accumulates and cannot be evacuated.
Key Risk Factors
- Colorectal cancer: the most common cause of LBO, responsible for approximately 60% of cases 1
- Diverticular disease: can lead to stricture formation and obstruction due to inflammation and scarring of the bowel wall
- Volvulus: twisting of the bowel around its mesenteric axis, causing obstruction and potential ischemia
- Fecal impaction: accumulation of hardened stool, predominantly affecting elderly, immobile, or neurologically impaired patients
Management and Treatment
The management of LBO depends on the underlying cause and may involve surgical intervention, such as resection and primary anastomosis, or non-surgical approaches, like endoscopic detorsion or stenting 1. In cases of malignant LBO, stenting as a bridge to surgery has been shown to reduce morbidity and mortality compared to emergency surgery 1.
Importance of Prompt Diagnosis and Treatment
Prompt diagnosis and treatment of LBO are essential to prevent complications such as perforation and peritonitis, which can significantly impact morbidity and mortality 1. Patients with risk factors for LBO should be closely monitored for symptoms, including abdominal distention, constipation, abdominal pain, and vomiting.
From the Research
Risk Factors for Large Bowel Obstruction (LBO)
The following are potential risk factors for Large Bowel Obstruction (LBO):
- Colorectal cancer: Studies have shown that colorectal cancer is a common cause of LBO 2, 3, 4.
- Strictures: Strictures, which can be caused by a variety of factors including inflammation and scar tissue, can also lead to LBO 2, 3.
- Diverticulitis: Diverticulitis, particularly acute complicated diverticulitis, has been shown to be associated with an increased risk of LBO and poor outcomes 5.
- Previous abdominal surgery: While the evidence is not conclusive, some studies suggest that previous abdominal surgery, particularly inguinal hernia repair, may be associated with an increased risk of diverticulosis, which can lead to LBO 6.
Common Etiologies of LBO
The etiologies of LBO can be classified into several categories, including:
- Intrinsic causes: Such as colorectal cancer and strictures 2, 3.
- Extrinsic causes: Such as adhesions and hernias 3.
- Benign causes: Such as diverticulitis and volvulus 3.
- Malignant causes: Such as colorectal cancer 2, 3, 4.
Management of LBO
The management of LBO depends on the underlying cause and severity of the obstruction, and may include: