BACKGROUND: Perioperative hypothermia is a frequent occurrence and can lead to several complications. The aim of this study is to evaluate the efficacy of warm fluid in maintaining normal core temperature during the intraoperative period. 
METHODS: We studied 30 American Society of Anesthesiologists (ASA) physical status I or II adult patients who required general anesthesia for abdominal surgery. In control group (n=15), fluids were infused at room temperature; in test group (n=15), fluids were infused at 37°C. Core temperature was measured at the tympanic site. During recovery, shivering was evaluated by an independent observer. 
RESULTS: The two groups did not differ significantly in patient characteristics. In control group, core temperature decreased to 35.5±0.3°C during the first 3 hours, and then stabilized at the end of anesthesia. In test group, core temperature decreased during the first 60 min, but increased to 36.9±0.3°C at the end of anesthesia. In control group, 8 patients shivered at grade ≥2. In test group, none of the patients reached grade ≥ 2 (P < 0.01).
CONCLUSIONS: Infusion of warm fluid is effective to keep patients nearly normothermic and prevent postanaesthetic shivering. It may provide an easy and effective method for perioperative hypothermia prevention.