Impact of a thermal care bundle on peri-operative hypothermia, surgical site infection, and readmissions in osteosynthesis patients: A randomised controlled trial.

Abstract

BACKGROUND: Maintaining normothermia throughout the peri-operative period prevents the occurrence of complications related to hypothermia. OBJECTIVE: To determine the effect of a thermal care bundle with a short prewarming period on inadvertent peri-operative hypothermia (IPH), surgical site infection (SSI), and unplanned readmission among osteosynthesis patients, and to identify associated variables. DESIGN: Open-label, randomised controlled trial. SETTING: University hospital. PATIENTS: One hundred and forty-eight patients who underwent osteosynthesis surgery. INTERVENTION: The intervention group received the thermal care bundle, which consisted in prewarming patients 10 min before anaesthesia delivery and maintaining body temperature with a forced air device during surgery and the immediate postoperative period; in addition, the operating room environmental temperature was kept at 21 °C, and fluids were warmed to 38 °C. MAIN OUTCOME MEASURES: For the primary objective, hypothermia was defined as core body temperature below 36 °C and measured using the 3M Spot On zero heat flux sensor. Core temperature was recorded upon admission to the pre-operative holding area and subsequently every 30 min until postanaesthesia care unit (PACU) discharge. Secondary objectives were SSI and readmissions: a follow-up at 30 to 60 and 90 days was performed by the principal investigator. RESULTS: All 148 patients completed the study, and there were no significant differences between the groups at baseline. At the start of surgery, the incidence of hypothermia was significantly lower in the bundle group (1.3 vs. 9.9% among controls; odds ratio = 7.59, P  = 0.021). A significantly lower incidence of hypothermia was also observed at admission to the PACU (14.3% in the bundle group vs. 29.6% among controls; odds ratio = 2.07; P  = 0.024). Application of the bundle increased patients' core body temperature by 0.13 °C (95% confidence interval (CI), 0.003 to 0.254; P  = 0.045). Patients in the bundle group had a slightly lower observed incidence of wound infections requiring readmission (odds ratio = 0.35; 95% CI, 0.04 to 2.92), although this difference was not statistically significant ( P  = 0.332). CONCLUSIONS: The bundle reduces peri-operative hypothermia by up to 59%, but does not affect on SSI; factors like presurgery hospital stay, operating room and PACU occupancy were identified as risk factors for SSI. REGISTRATION: 21 July 2022: NCT05469958 (Clinical Trials.gov), first recruitment 15 August 2022.