Surgical patients with methicillin resistant staphylococcus aureus infection: an analysis of outcome using P-POSSUM.

The significance of MRSA infection in surgical patients was studied using the P-POSSUM scoring system. All surgical patients undergoing operation between 1/10/96 and 30/09/97 were prospectively scored using P-POSSUM. A subset of these patients with MRSA infection was analysed using P-POSSUM predicted mortality. Physiological and operative severity scores were compared with non-MRSA surgical patients and length of hospital stay with P-POSSUM matched non-MRSA controls. Thirty of the 1,132 patients were MRSA positive and of these five died, giving a P-POSSUM observed/expected deaths ratio of 1.7 (not significant; 95% CI -0.24 to 0.10). The P-POSSUM physiology score of 30 MRSA positive patients, compared with the non-MRSA group (n = 1102), was significantly more severe (20.9 v/s 17.4; 95% CI 1.09 to 5.95) as was the operative severity score (15.6 v/s 9.2; 95% CI 4.40 to 8.42). The length of stay for surviving MRSA positive patients was significantly longer than P-POSSUM matched controls. MRSA infection in surgical patients does not increase mortality. However, patients who contract MRSA infection are more debilitated and have undergone a greater surgical insult.