46.07 Laparoscopic Converted to Open Appendectomy: Outcomes Comparison using Propensity Score Analysis

A. E. Wagenaar1, J. Tashiro1, J. C. Langer2, E. A. Perez1, J. E. Sola1  1University Of Miami,Surgery,Miami, FL, USA 2University of Toronto,Surgery,Toronto, Ontario, Canada

Introduction:  We hypothesized that clinical outcomes differ between laparoscopic appendectomy (LA) and laparoscopic converted to open appendectomy (CA).

Methods:  We queried the Kids’ Inpatient Database (1997-2012) for simple (540.9) and complicated (540.0, 540.1) appendicitis treated with LA or CA. Propensity score (PS)-matched analysis compared outcomes associated with LA and CA, using 41 pre-procedure variables (demographic and socioeconomic variables, hospital characteristics, facility preference for laparoscopy).

Results: Overall, 327,748 cases of simple appendicitis were treated with LA (98.9%) and CA (1.1%), whereas 64,394 cases of complicated appendicitis had LA (92.4%) and CA (7.6%).

On 1:1 propensity score (PS)-matched analyses of simple appendicitis (1976 LA: 2073 CA), CA had higher rates of wound infection (odds ratio: 4.2), pneumonia (4.0), transfusion requirement (3.7), sepsis (3.5), and other infections (2.0), p<0.04. Length of stay (LOS), total charges (TC), and cost were higher in CA vs. LA, p<0.001.

For complicated appendicitis (2747 LA: 2777 CA), CA had higher rates of incision and drainage of wound (17.9), intraoperative perforation (17.9), surgical misadventure (8.9), transfusion requirement (2.8), pneumonia (2.0), wound infection (1.9), sepsis (1.8), p<0.002. CA patients were more likely to require home healthcare upon discharge (2.9), p<0.001. LOS, TC, and cost were higher in CA vs. LA, p<0.001.

Conclusion: Conversion from laparoscopic to open is more common for complicated appendicitis and an indicator of significantly higher morbidity and resource utilization for both simple and complicated appendicitis. In a PS-matched comparison (including facility procedure preference) higher complication rates, LOS, TC, and cost were associated with cases converted to open.