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.

Insufficient cuff pressure of tracheal tube (TT) increases the risk of secretions aspiration and consequent pulmonary infection, whereas high pressure may cause tracheal injury. It is very important to control cuff pressure at the optimal status for air care providers. Volume control ventilation (VCV) is often applied to verify the cuff pressure. We used different volumes of syringe as simulated trachea, selected Proterx 7.0 tube to do the intubation, and recorded the volume of air ventilated and the corresponding intracuff pressure. The result indicated that pressures increased intensively when air volumes surpassed certain values, which suggested VCV method was not appropriate to control the intracuff pressure, and pressure control ventilation might be the better choice. In that case, air care providers have to improve their ability to control pressure. Herein, we enrolled 80 residents into sensitivity training for pressure. Trainees were required to palpate the pilot balloons of 12 tubes (Portex7.0) with different intracuff pressure repeatedly to sense the pressure, 1 hour/ day for 3 days. Trainees who could arrange tubes in turn and control the intracuff pressure at optimal range (20-30cm H2O) during intubation in model were considered eligible, the rest were trained continuously till eligible. Inappropriate percent －The proportion of residents who could not control intracuff pressure appropriately － were recorded before training, after training, one month, three months and six months after training. The results indicated that the training method was effective to improve the ability of residents to control the intracuff pressure, the inappropriate percent increased gradually over time, the average intracuff pressure surpassed the optimal value at six months post-training, suggesting six months should be time point for retraining.