Cost-effectiveness analysis of single use negative pressure wound therapy dressings (sNPWT) compared to standard of care in reducing surgical site complications (SSC) in patients undergoing coronary artery bypass grafting surgery

Abstract

Background: There is a growing interest in using negative pressure wound therapy in closed surgical incision to prevent wound complications which continue to persist following surgery despite advances in infection measures.

Objectives: To estimate the cost-effectiveness of single use negative pressure wound therapy (sNPWT) compared to standard of care in patients following coronary artery bypass grafting surgery (CABG) procedure to reduce surgical site complications (SSC) defined as dehiscence and sternotomy infections.

Method: A decision analytic model was developed from the Germany Statutory Health Insurance payer's perspective over a 12-week time horizon. Baseline data on SSC, revision operations, length of stay, and readmissions were obtained from a prospective observational study of 2621 CABG patients in Germany. Effectiveness data for sNPWT was taken from a randomised open label trial conducted in Poland which randomised 80 patients to treatment with either sNPWT or standard care. Cost data (in Euros) were taken from the relevant diagnostic related groups and published literature.

Results: The clinical study reported an increase in wounds that healed without complications 37/40 (92.5%) in the sNPWT compared to 30/40 (75%) patients in the SC group p = 0.03. The model estimated sNPWT resulted in 0.989 complications avoided compared to 0.952 and the estimated quality adjusted life years were 0.8904 and 0.8593 per patient compared to standard care. The estimated mean cost per patient was €19,986 for sNPWT compared to €20,572 for SC resulting in cost-saving of €586. The findings were robust to a range of sensitivity analyses.

Conclusion: The sNPWT can be considered a cost saving intervention that reduces surgical site complications following CABG surgery compared to standard care. We however recommend that additional economic studies should be conducted as new evidence on the use of sNPWT in CABG patients becomes available to validate the results of this economic analysis.

Keywords: CABG; Single use negative pressure wound therapy; cost-effectiveness; Surgical site complications.

Fig. 1

Model structure for sNPWT compared to SC in patients following CABG surgery. The decision tree model used to predict cost and outcome of sNPWT and standard of care. The tree maps the outcomes (health states) modelled following a complication or no complication. The branches for no complication are not shown in the figure

Fig. 2

Cost effectiveness acceptability curves for sNPWT compared to standard care in patients following CABG surgery. Cost-effectiveness acceptability curves depicting results of the probabilistic sensitivity analysis for the two interventions sNPWT and SC. The y-axis gives the probability that each intervention is cost effective as a function of willingness to pay shown on the x-axis. A willingness to pay of €50,000/QALY is within the bounds of accepted cost-effectiveness thresholds. The figure suggests there is little uncertainty regarding the cost-effectiveness of sNPWT compared to SC (100% probability that sNPWT is cost-effective)

Fig. 3

Cost-effectiveness plane for sNPWT compared to standard care in patients following CABG surgery. The cost-effectiveness plane shows results of the probabilistic sensitivity analysis for the two interventions sNPWT and SC. Each point on the plot corresponds to one trial in the Monte-Carlo simulation (2000 simulations were conducted) comparing the incremental effectiveness and incremental costs of sNPWT compared to SC. Costs for sNPWT were consistently lower (read on the y-axis) and effectiveness highest (read on the x-axis) for the SSC prevention following CABG compared to SC. The figure therefore shows that sNPWT is cost-saving