Risk Factors for Perforated Appendicitis in the Acute Care Surgery Era—Minimizing the Patient's Delayed Presentation Factor

Background: Numerous factors contribute to advanced disease or increased complications in patients with acute appendicitis (AA). This study aimed to identify risk factors associated with AA perforation, including the effect of system time (ST) delay, after controlling for patient time (PT) delay. In this study, PT was controlled (to less than or equal to 24 h) to better understand the effect of ST delay on AA perforation. Methods: Medical records of patients who underwent surgery for AA at a tertiary referral hospital from October 2009 through September 2013 were reviewed. Data collected included demographics, body mass index, presence of fecalith, PT (i.e., duration of time from symptom onset to arrival in emergency department), and ST (i.e., duration of time from arrival in emergency department to operating room). AA was classified as simple (acute, nonperforated) versus advanced (gangrenous, perforated). Results: Seven hundred forty-seven patients underwent surgery for AA. After excluding patients with PT > 24 h, 445 patients fit the study criteria, of which 358 patients with simple AA and 87 patients with advanced disease. Advanced appendicitis patients were older and had higher body mass index, longer PT, higher WBC, and higher incidence of fecaliths. Both groups had similar ST. Risk factors for advanced appendicitis after multiple regression analysis are age >50 y old, WBC >15,000, the presence of fecaliths, and PT delay >12 h. Conclusions: Once PT delay was limited to ≤24 h, the ST delay of >12 h did not adversely affect the incidence of advanced AA. Age >50 y, WBC >15,000, PT delay >12 h, and the presence of fecaliths were identified as risk factors associated with advanced AA.