Serratia marcescens bacteremia from contaminated pressure transducers.

Primary Serratia marcescens bacteremia developed in 17 patients in an intensive care unit after exposure to pressure monitoring devices. A study showed that all of the transducer heads were contaminated with S marcescens, and prospective culturing of 110 pressure monitoring lines disclosed a 24% rate of contamination with the same organism. Hand contamination occurs at the time the equipment is initially assembled; in five of eight trials, transmission was shown experimentally to occur by direct inoculation of open ports. Routine disinfection of the transducer heads with glutaraldehyde not only effectively decontaminated all pressure monitoring lines in use, but also controlled the outbreak.