New-onset intra-operative hyperthermia in a large surgical patient population: A retrospective observational study

BACKGROUNDIntra-operative hypothermia has been extensively investigated. However, the incidence of intra-operative hyperthermia has not been investigated in detail.OBJECTIVEThe 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.DESIGNRetrospective database review.SETTINGTertiary-care teaching hospital.PATIENTSPatients undergoing surgery with general anaesthesia between 1 January 2002 and 31 December 2017 were included.MAIN OUTCOME MEASURESThe 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.RESULTSA total of 103648 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 (>8h) 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.CONCLUSIONMild intra-operative hyperthermia is not uncommon particularly in longer procedures and small children.