An investigation into factors that affect oesophageal temperature during abdominal surgery

The purpose of this study was to examine factors which influence changes in body temperature during surgical operation. Variables included were ambient theatre temperature and humidity, duration of surgery, age of patient, index of body fat, blood loss during surgery, and the volume of intravenous fluids received. Subjects were 30 female patients undergoing elective abdominal gynaecological surgery. Body temperature was measured using oesophageal probes and data were collected for the duration of the operation. Patients sustained a mean reduction in oesophageal temperature of 1.03 degree C. Bivariate correlations indicated that ambient temperature, age, body fat, volume of intravenous fluids and blood loss were associated with temperature reduction at the level of < 0.05. Step-wise multiple regression revealed two possible models including ambient theatre temperature, each of which accounted for 70% of the variance. Model 1 included age, while model 2 included volume of intravenous fluids and index of body fat. It was noted that older patients were generally in theatre at a time when the ambient temperature was lowest. Recommendations are made to minimize unnecessary reductions in body temperature during surgery for vulnerable groups, notably elderly and thin patients.