Objective: The use of antibiotic-impregnated sponges (Collatamp) during cardiac surgery is controversial. We analysed the cost-effectiveness of its selective use in patients at high-risk of sternal wound infection (SWI).
Method: Postoperative costs were analysed in two groups of patients undergoing heart surgery between 2011 and 2013: those with SWI (group 1) and in high-risk patients without SWI (group 2). The potential cost of gentamicin-impregnated collagen sponges (GCS) use in high-risk patients was compared with our current practice.
Results: We identified 1,251 patients with at least one recognised risk factor for developing SWI in this period. Of these, 18 developed SWI (incidence 1.4%). The median postoperative cost per patient without SWI was £9,617. The additional cost per patient incurred by SWI was £4,860.75. The annual additional cost for treating patients with SWI was £43,749. With a 50% reduction in SWI, the annual additional cost of treating these patients would be reduced to £21,873. The cost of GCS is £80 per patient. Adding this to £21,873 gives a potential total cost of £71,913 in the treated high-risk cohort.
Conclusion: In our practice the annual cost of treating SWI in high-risk patients without use of GCS is lower than the annual cost of using GCS in all high-risk patients (£43,749 versus £71,913) if it produces a 50% reduction in SWI. The reduction in the incidence of SWI poses no economic benefit when the cost of the product is factored in.
Keywords: Collatamp; cost analysis; gentamicin-impregnated collagen sponge; sternal wound infection.