Acute Diverticulitis: High Mortality in Patients Undergoing Delayed Surgery: A Case-control Study

Abstract

Purpose: The indications and outcomes for emergency surgery in diverticulitis remain uncertain outside tertiary medical centers. Aim is to determine the clinical outcome of: (a) patients who undergo emergent surgery for diverticulitis (b) patients who have surgery after initial medical therapy has failed comparing them to patients who undergo elective surgery for diverticulitis (controls). Methods: All inpatients diagnosed with acute diverticulitis who had surgery at 3 teaching hospitals over a 9-year period were evaluated. To be included in our analysis patients were required to have undergone emergent (within 24 hrs of admission), semi-urgent (>24 hours after Admission+initial antibiotic therapy) or elective surgery for diverticulitis and to have had CT evidence of acute diverticulitis and/or histopathologic evidence of diverticulitis on the surgical specimen, Using ICD9 coding for diverticulitis, 608 patients were identified. Chart audits were performed to verify the accuracy of the codes and data were abstracted from individual patient records, 523 finally included. Results: The mean age of the cohort was 61 years (SD 15.2), 90% were Caucasians, 7% African Americans and 3% others. There were 69 emergency operations, 299 patients in the initial medical treatment (semi-urgent surgery) group and 155 patients controls (undergoing elective surgery). Number of days from admission to surgery was 0.4 days (SD 0.49) in emergent surgery groups and 1.25 days (SD 2.5) in semi-urgent surgery group. Length of hospitalization was similar between emergent and semi-urgent groups (mean of 12 days, SD 9.0) compared to 7.2 days (SD 3.9) in elective surgery group( p-value <0.001). Laparoscopic resection was performed in 5 (7.3%) patients in the emergent surgery group, 42 (14.1%) patients in semi-urgent group and 19 (12.3%) patients in elective surgery group (p-value 0.305). total mortality of 15 patients (2.8%), 12 patients had in hospital mortality (1 patient in emergent surgery group and 11 patients in semi-urgent surgery group and none in the elective surgery group p-value 0.029) and 3 patients died within 30 days (1 patient in emergent surgery, 2 patients in semi-urgent surgery and none in elective surgery, p-value 0.273). Malignancy in the diverticulitis segment was detected in 3 patients (0.57%) all in semi-urgent surgery group (p-value 0.709). Conclusion: 1. There is a significant mortality in patients undergoing emergent surgery for acute diverticulitis compared to patients who undergo elective surgery for the same indication. 2. Delayed surgery after failure of antibiotic therapy is associated with a higher mortality. 3. Further research will help determine the factors that should dictate early surgery.