Central venous catheter (CVC) infections are a significant cause of morbidity and death in critically ill patients. Recent multipronged quality-improvement efforts have the potential to decrease the rates of CVC-related infections. Researchers evaluated the impact of chlorhexidine-impregnated sponge dressings on catheter-related infections and assessed whether scheduling dressing changes every seven days instead of every three days would have an adverse effect on adult ICU patients.

A large, multicenter trial was conducted in five hospitals in France over a 17-month period. Patients (N = 1,636) older than 18 years who were expected to need either an arterial catheter or a CVC for at least 48 hours were recruited from medical and surgical ICUs and randomized to one of four groups: chlorhexidine-impregnated sponge dressing changed every three days, standard dressing changed every three days, chlorhexidine sponge dressing changed every seven days, and standard dressing changed every seven days. All dressings were to be changed at the first sign of leakage or soiling regardless of the assigned schedule.

In comparing the chlorhexidine-impregnated dressing with the standard dressing, the primary outcome was the rate of major catheter-related infection, defined as catheter-related clinical sepsis without bloodstream infection or catheter-related bloodstream infection. In comparing the seven-day dressing-change interval with the three-day interval, the primary outcome was catheter colonization. Secondary outcomes included catheter-related bloodstream infection and skin colonization.

Use of chlorhexidine-impregnated sponge dressings decreased the rate of major catheter-related infections by 60% and significantly decreased the rates of catheter colonization and catheter-related bloodstream infections. Contact dermatitis was reported more frequently in the chlorhexidine-impregnated dressing group (1.49% versus 1.02%), seen most often in patients with multiple organ failure, subcutaneous edema, and fragile skin. Dermatitis was severe enough in eight patients to require permanent removal of the sponge dressing.

Increasing the interval between dressing changes didn't result in an increased risk of catheter colonization. However, only 10% of the dressings in the seven-day group were in place for seven days because most required unscheduled changes.

The cost of preventing a single episode of catheter-related infection using drug-impregnated dressings was estimated to be about $2,106, whereas the cost of treating one catheter-related infection ranges from $8,000 to $28,000, making the use of such dressings a cost-effective measure to add to an existing preventive protocol. It's also safe to schedule dressing changes for seven-day intervals, but nurses must assess the dressings frequently and change them if they become loose or show signs of leakage or soiling.