Infection related to intravascular pressure monitoring: effects of flush and tubing changes

The optimal frequency for changing pressure monitoring tubing and flush solution that minimizes catheter-related infection and contains cost has not yet been established. We conducted a pilot study to examine the effects of three protocols on catheter-related infection: group I, change of flush solution and pressure monitoring tubing every 24 hours; group II, change of flush solution every 24 hours and change of pressure monitoring tubing every 48 hours; group III, change of flush solution and pressure monitoring tubing every 48 hours. Thirty critically ill patients were randomly assigned to one of the three protocols. Semiquantitative cultures of the solution from the flush bag and catheter tip were obtained. Intervening variables were documented: duration of cannulization, number of entries into the system, presence of other invasive devices, white cell count, patient's temperature, presence of preexisting infection, patient's age and diagnosis, use of steroids and antibiotics, and host risk factors for immunocompromise. All flush solution cultures were negative for growth. Incidence of catheter-related bacteremia was zero. The cultures of four catheter tips were positive for Staphylococcus epidermidis; none in group I, three in group II, and one in group III. The results of this pilot study suggest that there is no difference in the incidence of catheter-related infection whether the change interval for flush solution and pressure monitoring solution is 24 or 48 hours. However, further study with a larger sample is needed.