Open Versus Laparoscopic Appendectomy: A Post Hoc Analysis of the EAST Appendicitis MUSTANG Study

We sought to understand which factors are associated with open appendectomy as final operative approach. We hypothesize that higher American Association for the Surgery of Trauma (AAST) Emergency General Surgery (EGS) grade is associated with open appendectomy. Post hoc analysis of the Eastern Association for the Surgery of Trauma (EAST) Multicenter Study of the Treatment of Appendicitis in America: Acute, Perforated and Gangrenous (MUSTANG) prospective appendicitis database was performed. All adults (age >18) undergoing appendectomy were stratified by final operative approach: laparoscopic or open appendectomy (including conversion from laparoscopic). Univariable analysis was performed to compare group characteristics and outcomes, and multivariable logistic regression was performed to identify demographic, clinical, or radiologic factors associated with open appendectomy. A total of 3,019 cases were analyzed. One hundred seventy-five (5.8%) patients underwent open appendectomy, including 127 converted from laparoscopic to open. The median age was 37 (25) years and 53% were male. Compared with the laparoscopic group, open appendectomy patients had more comorbidities, higher proportion of symptoms greater than 96 hours, and higher AAST EGS grade. Moreover, on intraoperative findings, the open appendectomy group had a higher incidence of perforated and gangrenous appendicitis with purulent contamination, abscess/phlegmon, and purulent abdominal/pelvic fluid. On multivariable analysis controlling for comorbidities, clinical and imaging AAST grade, duration of symptoms, and intra-operative findings, only AAST Clinical Grade 5 appendicitis was independently associated with open appendectomy (odds ratio [OR], 5.63; 95% confidence interval [CI], 1.24-25.55; p = 0.025). In the setting of appendicitis, generalized peritonitis (AAST Clinical Grade 5) is independently associated with greater odds of open appendectomy.