Efficacy and Safety of Forced-Air Warming System versus Passive Warming Measures in Major Surgeries: A Systematic Review

Purpose: To compare the clinical impact of forced-air warming system (Bair HuggerTM, BH) and passive warming measures in major surgery patients. Methods: Databases including Pubmed, Cochrane Library, Clinical Trials.Gov and CNKI were searched to collect studies published before January 2019 that were concerned the clinical effects of Bair Hugger. Two reviewers independently screened the literatures, extracted the data. The revised Jadad scale was used to evaluate the methodological quality of the literatures. Meta-analysis was performed by using Review Manager 5.3.0. Findings: A total of 27 studies were included. The result of meta-analysis showed that BH had a significant advantage in rate of hypothermia (RD = -0.42, 95%CI (-0.68, -0.16)) , shivering (RD = -0.28, 95%CI (-0.43, -0.13)), anesthesia recovery time (MD = -8.27, 95% CI (-13.49, -3.05)), hospital stay (MD = -1.27, 95% CI (-2.05) , -0.48)), while incision infection RD = -0.15, 95%CI (-0.40,0.11)) , intraoperative blood loss (MD = -16.88, 95%CI(-34.73,0.96)), intraoperative blood transfusion (MD = -41.49, 95% CI( -108.36, 25.38)) , pain RD = -0.02, 95%CI(-0.08, 0.03)) and other complications (RD = -0.13, 95%CI(-0.39,0.12)) had an advantage but not significant. Subgroup analyses showed that operation mode and operation duration was the sensitive factors. Conclusion: Compared to passive warming, Bair Hugger has significant advantages in hypothermia protection and further reduces the risk of incision chills and prolonged hospital stay. Combined with the current status of body temperature protection in China, it is necessary to enhance the awareness of body temperature protection, standardize medical behavior, and increase the popularity of active warming systems.