Association between Normothermia at the End of Surgery and Postoperative Complications following Orthopaedic Surgery

BACKGROUND: Maintaining perioperative normothermia is recommended by recent guidelines for the prevention of surgical site infections (SSIs). However, the majority of supporting data originates outside the field of orthopaedic surgery. METHODS: The effect of normothermia was explored using the prospectively collected data of consecutive patients who underwent single-site surgery in 7 tertiary referral hospitals between November 2013 and July 2016. SSIs, urinary tract infections (UTIs), respiratory tract infections (RTIs), cardiac and cerebral events (CCE), and all-cause mortality rates within 30 days after surgery were compared between patients with normothermia (body temperature >/=36 degrees C) and those with hypothermia (<36 degrees C) at the end of surgery, after closure. Multivariable adjusted and inverse-probability weighted regression analyses were performed. RESULTS: The final cohort included 8841 patients. Of these, 11.4% (n = 1008) were hypothermic. More than 96% were evaluated in person by the physicians. After adjusting for multiple covariates, normothermia was not significantly associated with SSIs (adjusted odds ratio [aOR] 1.18, 95% confidence interval [CI] 0.59-2.33), UTIs (aOR 1.14, 95% CI 0.66-1.95), RTIs (aOR 0.60, 95% CI 0.31-1.19), or CCE (aOR 0.53, 95% CI 0.26-1.09). In contrast, normothermia was associated with a lower risk of 30-day mortality (aOR 0.26, 95% CI 0.11-0.64; P < .01; weighted hazard ratio 0.21, 95% CI 0.07-0.68; P = .002). In a subgroup analysis, normothermia was associated with reduced mortality in all types of surgical procedures. CONCLUSIONS: Whereas our findings suggest no clear association with SSI risks following orthopedic surgery, our study supports maintaining perioperative normothermia, as it is associated with reduced 30-day mortality.