SEVERITY AND PREDICTED OUTCOME OF POSTOPERATIVE PSEUDOMONAS-AERUGINOSA INFECTIONS

The severity and predicted outcome of postoperative Pseudomonas aerugi nosa (P. aeruginosa) infections (PPAI) was evaluated using a severity scoring system based on a simplification and modification of the APACH E II system. A total of 86 patients in whom P. aeruginosa was isolated from various sources were examined. PPAI developed in 50 patients, re sulting in an overall mortality rate of 24%. An increased severity sco re (SS) correlated with an increased risk of developing PPAI. Thus, PP AI developed in 33% of the patients with an SS of 0-1, in 66.7% of tho se with an SS of 2-3, and in 100% of those with an SS of 6 or higher. Moreover, the mortality rate of the patients with an initial score of 6 or higher was 50%. The mean (+/- SD) initial severity score was 5.4 +/- 2.9 for survivors and 2.9 +/- 2.6 for nonsurvivors (P < 0.01). In the patients who subsequently died, the SS remained high throughout th e clinical course despite therapy, whereas in the survivors the SS dec reased progressively, reflecting a favorable clinical course. These re sults suggest that our severity scoring system was useful for predicti ng outcome and monitoring the response of PPAI to therapy.