E-2 CLINICAL EFFECTIVENESS AND COST EFFECTIVENESS OF GEL OVERLAYS TO PREVENT PRESSURE ULCERS IN SURGICAL PATIENTS

Tuesday, October 20, 2009: 1:15 PM
Grand Ballroom, Salon 5 (Renaissance Hollywood Hotel)
Ba' Pham, MSc, PhD, (c)1, Laura Teague, RN, MN, NP-Adult2, James Mahoney, MD2, Laurie Goodman, RN, BA3, Anita Stern, PhD4, Jeff Poss, PhD5, Jianli Li, PhD2, Nancy Sikich, PhD6, Rosemarie Lourenco, CHIM, IMS6, Luciano Ieraci, MSc4, Steven Carcone, MSc1, William Witteman, MISt4 and Murray D. Krahn, MD, MSc4, (1)Toronto Health Economics and Technology Assessment Collaborative, Toronto, ON, Canada, (2)St. Michael's Hospital, University of Toronto, Canada, Toronto, ON, Canada, (3)The Credit Valley Hospital, Mississauga, ON, Canada, (4)University of Toronto, Toronto, ON, Canada, (5)University of Waterloo, Waterloo, ON, Canada, (6)Ontario Ministry of Health and Long-Term Care, Toronto, ON, Canada

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