Demonstrating the clinical and cost effectiveness of adhesion reduction strategies

OBJECTIVE: To examine the feasibility of conducting Randomized Controlled Trials (RCT) in lower abdominal surgery to demonstrate a reduction in adhesion-related admissions following use of an adhesion reduction product, and to model the cost effectiveness of such products. METHODS: The number of patients in each limb of a RCT comparing an adhesion reduction product to a control has been estimated based on 25% and 50% reductions in adhesion-related readmissions one year after surgery, for P = 0.05 at a power of 80% and P=0.01 at a power of 90%. A cost effectiveness model based on the Surgical and Clinical Adhesions Research Group (SCAR) database has been developed which calculates the percentage reduction in readmissions required of an adhesion reduction product to return the cost of investment. It also estimates the cumulative costs of adhesion-related readmissions for lower abdominal surgery and the cost savings associated with an adhesion reduction policy using a low or high cost product. RESULTS: 7.2% of patients undergoing lower abdominal surgery will readmit due to adhesions in the first year after surgery. To demonstrate a 25% reduction in readmissions one year after surgery, it is calculated that a RCT would require between 5686 (P = 0.05, power=80%) and 7766 (P = 0.01, power = 90%) lower abdominal surgery patients followed-up for one year. A cost effectiveness analysis demonstrates that routine use of adhesion reduction products costing pound 50 per patient will payback the cost of such investment if they reduce adhesion-related readmissions by 16% after 3 years. A product costing pound 200 will need to offer a 64.1% reduction in readmissions after 3 years. For the estimated 158 000 lower abdominal surgery operations conducted in the UK each year, the cumulative costs of adhesion-related readmissions over 10 years are estimated at pound 569 Million. CONCLUSION: Demonstrating the clinical effectiveness of adhesion reduction products in the RCT setting is unlikely to be feasible due to the large number of patients required. Products costing pound 200 or more are unlikely to payback their direct costs.