Evidence-based, cost-effective management of large bowel obstruction: An algorithm of the Journal of Trauma and Acute Care Surgery Emergency General Surgery Algorithms Work Group

摘要

This algorithm was developed by the Journal of Trauma and Acute Care Surgery Emergency General Surgery Algorithms Work Group,1 to provide an evidence-based practical approach to the initial evaluation and management of large bowel obstruction (LBO) presenting in the emergency setting. The algorithm is intended to serve as a bedside reference for clinicians. It is annotated with letters linked to corresponding text that provides the rationale and references to support these recommendations. This algorithm (Fig. 1) is not a substitute for the clinical judgment and experience of bedside clinicians and should not be considered as the “standard of care.” We encourage institutions to use these recommendations to formulate local clinical protocols but recognize that there are patient-specific factors and institutional factors that may require deviation from this algorithm.Figure 1: Large bowel obstruction diagnosis and management.Large bowel obstruction may require urgent or emergent surgical intervention and is associated with significant mortality, ranging from 10% to 20%.2 Large bowel obstruction account for approximately 25% of all intestinal obstructions and are caused by intrinsic luminal obstruction or extrinsic compression.3,4 Despite advances in colorectal cancer screening, LBO remains a common initial presentation in up to 30% of patients with colorectal malignancies, particularly among patients 70 years or older.5–7 Other etiologies of LBO include volvulus, diverticular disease, and strictures, with the majority of obstructions occurring distal to the transverse colon.8,9Table 1 lists the causes of LBO and their corresponding percentages. The incidence of LBO and its impact increase with age, as older adults are at higher risk because of comorbidities, a consequence of their physiological decline, immune dysregulation, increased systemic inflammation, and anatomical changes.4,7 This underscores the importance of timely diagnosis and management, as outlined in the accompanying algorithm, to improve patient outcomes. TABLE 1 - Causes of LBO Cause Percentage of Presentation Malignancy 60 Colorectal cancer Metastatic cancer Pelvic or peritoneal tumors Volvulus Sigmoid 9–15 Cecal 1–2 Diverticular 10 Others* 13 *Includes foreign bodies, intussusception, diverticular strictures, endometriosis, ischemic stenosis, fecal impaction, hernia, inflammatory bowel disease stenosis, anastomotic strictures, Crohn's strictures, retroperitoneal fibrosis, and adhesions. INITIAL EVALUATION AND MANAGEMENT The initial evaluation of a patient with abdominal pain requires a detailed history and thorough physical examination. Patients with LBO usually present with infraumbilical crampy abdominal pain, distension, and obstipation. Compared with those with small bowel obstruction, LBO patients are less likely to have nausea and vomiting, unless presenting late in their course or having an incompetent/absent ileocecal valve.10,11 Understanding the timing of symptom onset can help distinguish the causes of LBO. A rapid onset is more common in patients with volvulus, whereas a gradual onset may indicate a malignant or stricturing lesion. Past episodes of left lower quadrant pain suggest diverticular disease, while a history of dark/tarry stools or change in stool caliber, weight loss, and fatigue may indicate malignancy.12 Abdominal examination may find tenderness, abdominal distension, and hyperactive or absent bowel sounds. Digital rectal examination is indicated and can be diagnostic if an intrinsic lesion is found, suggestive of rectal cancer.13 If there are vital sign abnormalities (i.e., fever, tachycardia, hypotension) along with peritonitis, perforation should be suspected, and immediate surgical intervention is warranted. Laboratory tests results such as leukocytosis and lactic acidosis might be suggestive of ischemia.14 Imaging is required for definitive diagnosis. Abdominal plain x-ray is often the first step when there is clinical suspicion o