Negative Pressure Therapy after Median Sternotomy on Closed Incision: A Randomized Controlled Study

Objectives: Surgical site infections (SSIs) are serious complications after cardiothoracic surgery and contribute significantly to postoperative morbidity, mortality, and healthcare costs. Negative pressure wound therapy (NPWT), in this case PICO dressing, is a concept introduced initially to assist in the treatment of chronic open wounds. Recently, there has been growing interest in using the technique on closed incisions after surgery to prevent potentially severe surgical site infections and other wound complications, but has not yet been rigorously tested in a randomized controlled trial. The purpose of this study was to evaluate NPWT as a prevention and therapy of superficial infection.

Methods: In this single-center, superiority designed prospective randomized controlled trial, patients after cardiac surgery performed via median sternotomy (n = 528) were after stratification according to the marker body mass index (BMI ≥35 yes/no) randomized to receive either a disposable PICO dressing (PD) (Smith & Nephew, the Netherlands) (n = 56/193) or a standard dry dressing (SDD) (n = 66/213) over the incision immediately at the conclusion of surgery. We have examined the development of infection depending on the type of dressing. The primary end point was SSIs within 30 days.

Results: The study showed no significant difference in the number of infections after operation in patients with BMI ≥35 (p = 0.622). In patients with BMI <35, there was no significant difference in the number of infections after operation (PD/SDD 20.8%/16%; p = 0.2926), but there was significant difference in the progress of the infection. In the PD group, 57.7% of infections remained superficial and 42.3% emerged a deep infection. Compared with SDD group, 32.5% of infections remained superficial and 67.5% emerged a deep infection (p = 0.0432).

Conclusion: These results suggest that the use of PD compared with SDD did not improve the rate of SSIs in 30 days, but PD treatment reduced the rate of deep type of SSIs; so, there is a shift toward more superficial and thus less feared and also less costly SSIs. It should be a standard to use the PD in patients with BMI <35 suffering from superficial infection in the surgical wound after median sternotomy.