EFFECTS OF CLOSED-SYSTEM DRAIN IN SURGERY - FOCUS ON METHICILLIN-RESISTANT STAPHYLOCOCCUS-AUREUS

Objective: The emergence of methicillin-resistant Staphylococcus aureu s (MRSA) has made a strong impact on the strategy of peri-operative an tibiotic prophylaxis, since MRSA has become one of the most common cau sative organisms of nosocomial infection in recent years. In this stud y, we conducted a bacteriological evaluation of surgical drains before and after introducing strategies to decrease MRSA infection rates. De sign and Patients: Between January 1987 and December 1994, we performe d a total of 2,755 surgical operations on inpatients, including 1,635 major and 1,120 minor operations. Almost all surgical drains were exam ined bacteriologically when they were removed. The number of drains ex amined was 460 +/- 47 (mean +/- SEM) per year. Since the increased inc idence of MRSA infection, we started exclusively using a closed draina ge system and first-generation cephalosporins in 1991. The strategy wa s evaluated by comparing the positive rates of drain cultures, changes in bacteriological features, and incidence of MRSA infection for the 4-year periods before and after 1991. Results: The positive rate of ba cteria in the drains decreased significantly (p < 0.01) from 25 +/- 2 to 16 +/- 1%. Bacteriologically, the positive rate of Staphylococcus s pp. decreased significantly (p < 0.05) from 7 +/- 2 to 3 1 0.3%. Posit ive rates of MRSA decreased significantly (p < 0.05) from 2.1 +/- 0.3 to 1.3 +/- 0.3%. Streptococcus declined dramatically from 3.0 +/- 0.3 to 0.3 +/- 0.1%. Of gram-negative strains, Pseudomonas and Escherichia coli were most often isolated. They showed no significant difference in positive rates between the terms. Conclusion: A closed drainage sys tem and thorough use of the first-generation cephalosporins for prophy laxis were effective in decreasing positive bacterial culture of drain s and reducing the incidence of MRSA on drains after surgery.