It is well known that surgery performed under general anesthesia commonly results in hypothermia. Surgical hypothermia is a serious, but preventable, condition. It is becoming increasingly important, however, to provide decision-makers with evidence of the cost-effectiveness as well as the clinical benefit of preventive measures. OBJECTIVE: Using the hospital perspective, the outcomes and cost-effectiveness of the Arctic Sun Model 100 for the prevention of hypothermia in patients undergoing off-pump coronary artery bypass surgery is explored. METHODS: Data for the cost-effectiveness analyses were obtained from a case control study and two randomized controlled trials comparing the surgical outcomes related to temperature control using the Arctic Sun versus the current surgical warming methods. The incremental cost-effectiveness per hypothermia case avoided was calculated by measuring the extra costs to the hospital for achieving an extra unit of effectiveness by using the Arctic Sun. RESULTS: Using the definition of hypothermia as a temperature less than 36°C, there were three cases (5%) of post-operative hypothermia out of 58 for patients warmed using the Arctic Sun method. Using the standard of care, 23 out of 48 patients (48%) were hypothermic. The treatment costs for preventing post-operative hypothermia includes $60 in variable costs for the standard of care. Costs for using the Arctic Sun for preventing post-operative hypothermia included $350 in variable costs and $9.85 in allocated annual fixed costs (total treatment cost - $359.85 per patient). Subtracting the relative cost to treat 100 patients using the standard of care ($6,000) from the relative cost of warming 100 patients using the Arctic Sun ($35,985) yielded an incremental cost effectiveness of $697.33 per post-operative hypothermia case avoided by using the Arctic Sun. CONCLUSION: Use of the Arctic Sun(tm) is both effective and cost-effective in preventing post-operative hypothermia during OPCAB procedures.