Susceptibility of intra-abdominal isolates at operation: a predictor of postoperative infection.

Antimicrobial resistance of operative site flora was correlated with postoperative infection in 175 patients undergoing operation for intra-abdominal sepsis: Diagnoses for study patients were acute or gangrenous appendicitis in 48 (27%), complicated appendicitis in 98 (56%), perforated viscus other than appendix in 21 (12%), and eight (5%) had other intra-abdominal infections. One hundred thirty-six (78%) patients were males. The average age was 33 +/- 14 years, average number of hospital days was 11.6 +/- 13.5, and average number of days on antibiotics was 6.9 +/- 2.5. Overall recovery without infection was 75 per cent (131/175). Analysis of susceptibility of 939 intraoperative isolates indicated a significant relationship (P = 0.0002) between resistance to the empiric antimicrobials received and postoperative infection. Of 131 patients with resolution of the intra-abdominal infection, 57 (44%) had resistant isolates while 36 (82%) of 44 patients with postoperative infectious complications had resistant isolates. Streptococcus Group D, Escherichia coli, and Bacteroides fragilis were the most prevalent resistant organisms isolated from both intra- and postoperative cultures. Other variables that were significantly different between those without complications and those who had complications were, respectively: average age 31 versus 38; admission WBC 14.5 versus 16.7; and diagnosis, acute appendicitis 28 per cent versus 2 per cent. A stepwise logistic regression analysis confirmed the predictive value of intraoperative isolate resistance, age, and admission WBC, in that order, on outcome.

RCT Entities:   Population Interventions Outcomes