2010 Papers - Asarias

Incidence of Postoperative Intra-abdominal Abscesses in Open Versus Laparoscopic Appendectomies

Jennifer Asarias Department of Surgery, Tripler Army Medical Center

Background: Risk for intra-abdominal abscess (IAA) after laparoscopic appendectomy (LA) remains controversial. A 2008 Cochrane review suggests almost a three-fold increase in incidence of IAA after LA compared with open appendectomy (OA).

Methods: We completed a retrospective chart review for all appendicitis patients age 18 years and older, undergoing appendectomy from 1996-2007 at one military treatment facility and one civilian hospital in Hawaii. Data collection included demographics, procedure, presence of complicated appendicitis (defined as perforated or gangrenous appendicitis on surgical or pathological assessment), and presence of post-operative IAA on CT scan.

Results: We identified 2464 patients with appendicitis, including 1,924 LA and 540 OA cases. Forty-two LA patients formed IAAs (2.18%) versus 10 OA patients (1.85%), with no statistically significant difference. Of 644 patients with complicated appendicitis, 27 out of 447 LA patients developed IAA (5.70%), compared with 7 out of 163 OA patients (4.12%), also not statistically significant. Only 0.99% of uncomplicated cases resulted in IAA versus 5.28% among complicated cases (p <.0001, OR 5.58). This is the largest retrospective chart review comparing the incidence of IAAs in LA vs. OA, with a 71% probability of detecting a 2-fold difference and a 99% probability of detecting a 3-fold difference if they existed.

Conclusions: Patients with complicated appendicitis were five times as likely to develop IAA compared to uncomplicated cases. This is the first adequately-powered retrospective chart review comparing incidence of IAA in LA vs. OA. These results differ from the consensus of the recent literature, with no significant difference found between the two procedures.