Purpose: New pressure ulcers (PU) occur in many patients undergoing elective surgery (7%-66%). We evaluated the cost-effectiveness of GFOs in support of guideline recommendations by the Ontario Health Technology Assessment Committee.
Methods: Study design: Cost-utility analysis, third-party payer perspective, 1-year time horizon, 2009 Canadian $. Population: patients undergoing a planned major surgical procedure (e.g. > 90 minutes). Comparators: GFO versus standard OR surfaces (STD). Decision model: A 21-state, 1-day-cycle Markov model calibrated to reproduce stage-specific hospital-acquired PU (H-A PU) prevalence reported by the Toronto Tri-Hospital Survey (n=1,118 patients). Input data: Effectiveness: Recent systematic reviews of preventive interventions identified three RCTs evaluating overlays for OR tables. In surgical patients, gel-filled overlays (GFO) significantly decrease early and mostly intact skin PUs one-day post-operation (RR: 0.53; 95% CI: 0.33-0.85), according to a well-designed 1998-RCT (n=446). Cost: Each GFO costs $878. A case-control design was used to obtain stage-specific PU-attributable inpatient [post discharge] costs, n=3,780 PU cases [n=21,578 home care clients] from the Ontario Case Costing Initiative [interRAI -Home Care] database. Controls were matched to PU cases by age groups, gender, admission diagnosis, and Charlson co-morbidity [Activity of Daily Living] score. PU-attributable inpatient [home care] costs were cost differences between cases and controls: $11,967 [$57/week], $12,951 [$81/week] and $21,797 [$105/week] for stages 2-4, respectively. Health utility: Similarly, a utility decrement estimate attributable to PU stage 2-4 versus 0-1 of 6.1% (3.9%, 8.3%) was obtained using data from the Minimum Data Set – Health Status Index (n=18,321 nursing home residents). This was applied to a mean utility of 0.44 for hospitalized patients from a published study (n=1,207).
Results: The prevalence of hospital acquired PU was projected to be 13.3% (12.3, 13.6) among GFO patients, and 16.6% (15.6, 17.0) among STD patients, with an estimated NNT=30 (29, 35). A GFO could be used for approximately 1,500 procedures over 2 years. Estimated QALY gained per person with GFOs was 0.00152 (0.00054, 0.00360) and cost saving $225 ($76, $647; $169 in-patient and $56 post-discharge costs). Probabilistic sensitivity analysis showed a 99% chance of higher net benefit with GFOs. Conclusions: The use of GFOs in surgical patients with a major surgical procedure is highly economically attractive.
Candidate for the Lee B. Lusted Student Prize Competition