Introduction: Predictors of conversion to open appendectomy during laparoscopic appendectomy (LA) are poorly defined in the modern era in which most patients undergo CT scanning prior to surgery.

Methods: Retrospective review of 940 consecutive LAs for suspected appendicitis in a single institution (2000-2006). Patient demographics, history and physical exam findings, WBC and differential, CT findings, surgeon identity, and operative findings were assessed. Surgeon identity was assessed by comparing the ten most frequent attending surgeons, collectively accounting for 85% of cases, versus those who rarely performed LA. [Stats: chi square and student t tests, binary logistic regression analysis with conversion as the dependent variable, p<0.05].

Results: 39 (4.1%) patients required conversion; the rate did not vary over the course of the study. Factors related to conversion on univariate analysis included advanced age, male gender, ASA>2, longer duration of symptoms, abdominal rigidity, greater % neutrophils on WBC differential, extraluminal air on CT, surgeon identity, retrocecal appendix, gross necrosis or perforation, or turbid/purulent ascites. By multivariable analysis, older age, male gender, ASA >2, attending surgeon’s identity, and retrocecal appendix were independently and significantly associated with conversion (see table).

Conclusions: Despite increasing experience with laparoscopic appendectomy, ~4% of patients continue to require conversion to an open procedure. Advanced age, male gender, ASA score >2, frequency with which the surgeon performs LA, and retrocecal location of the appendix are factors significantly and independently associated with conversion. These factors may help identify cases in which strong consideration should be given to proceeding directly with open appendectomy, potentially leading to reduced operative time and number of incisions.