[Post-appendectomy surgical site infection: overall rate and type according to open/laparoscopic approach]

To compare the incidence and profile of surgical site infection (SSI) after laparoscopic (LA) or open (OA) appendicectomy.

Observational and analytical study was conducted on patients older than 14years-old with suspected acute appendicitis operated on within a 4-year period (2007-2010) at a third level hospital (n=868). They were divided in two groups according to the type of appendicectomy (LA, study group, 135; OA, control group, 733). The primary endpoint was a surgical site infection (SSI), and to determine the overall rate and types (incisional/organ-space). The risk of SSI was stratified by: i)National Nosocomial Infection Surveillance (NNIS) index (low risk: 0E, 0 and 1; high risk: 2 and 3); ii)status on presentation (low risk: normal or phlegmonous; high risk: gangrenous or perforated). The statistical analysis was performed using the software SPSS. The main result and stratified analysis was determined with χ(2), and the risk parameters using OR and Mantel-Haenszel OR with 95%CI, accepting statistical significance with P<.05.

Age, gender, ASA index and incidence of advanced cases were similar in both groups. The overall SSI rate was 13.4% (more than a half of them detected during follow-up after discharge). Type of SSI: OA, 13% (superficial 9%, deep 2%, organ-space 2%); AL, 14% (superficial 5%, deep 1%, organ-space 8%) (overall: not significant; distribution: P<.000). Stratified analysis showed that there is an association between incisional SSI/OA and organ-space SSI/LA, and is particularly stronger in those patients with high risk of postoperative SSI (high risk NNIS or gangrenous-perforated presentation).

OA and LA are associated with a higher rate of incisional and organ-space SSI respectively. This is particularly evident in patients with high risk of SSI.