New-onset intra-operative hyperthermia in a large surgical patient population

BACKGROUND Intra-operative hypothermia has been extensively investigated. However, the incidence of intra-operative hyperthermia has not been investigated in detail. OBJECTIVE The main objective of this study was to assess the incidence and risk factors of new-onset intra-operative hyperthermia in a large surgical patient population. DESIGN Retrospective database review. SETTING Tertiary-care teaching hospital. PATIENTS Patients undergoing surgery with general anaesthesia between 1 January 2002 and 31 December 2017 were included. MAIN OUTCOME MEASURES The primary outcome measurement was new-onset intra-operative hyperthermia (>37.5 °C). A logistic regression model was fitted to identify risk factors for intra-operative hyperthermia. RESULTS A total of 103 648 patients were included in the final analyses. The incidence of new-onset hyperthermia in the overall patient cohort was 6.45%, reaching 20 to 30% after prolonged (>8 h) surgery, and was up to 26.5% in paediatric patients. The use of forced air active patient warming, larger amounts of fluid administration, longer surgery, younger age and smaller body size were all independently associated with intra-operative hyperthermia. The adoption of the Surgical Care Improvement Project (SCIP) temperature measures was associated with an increased incidence of intra-operative hyperthermia. CONCLUSION Mild intra-operative hyperthermia is not uncommon particularly in longer procedures and small children.