Examination of intra-operative core temperature in joint arthroplasty: a single-institution prospective observational study

Purpose Peri-operative hypothermia is associated with increased blood loss, delayed wound healing, and surgical site infections. However, it is not known when or how rapidly hypothermia develops during arthroplasty. This study observed patients undergoing lower extremity arthroplasty to identify the times of greatest heat loss or gain. Methods This single-institution prospective observational study enrolled 120 patients undergoing elective knee or hip arthroplasty for peri-operative temporal temperature measurements at ten prespecified intervals. Incidence of hypothermia was the primary outcome. A secondary aim was to identify patient and operative factors associated with hypothermia. Descriptive statistics were calculated for fixed time variables. Associations for the occurrence of hypothermia over time were conducted using generalized linear mixed models with a logit link and a random subject effect to account for repeated measures on the same individual over time. Results Most patients, 72.6%, experienced hypothermia with 20.6% hypothermic for over one hour and 47.1% hypothermic after surgery. In the multivariable model, increased odds of hypothermia were associated with female gender ( P = 0.017), knee arthroplasty ( P