Effects of aggressive warming on intraoperative temperature and cardiac troponin I in patients undergoing radical resection of esophageal carcinoma

Objective To observe the effects of aggressive warming on intraoperative temperature and cardiac troponin I (cTnI) in patients undergoing radical resection of esophageal carcinoma. Methods Ninety patients undergoing elective radical resection for esophageal carcinoma, aged 45-75 y, ASA Ⅰ or Ⅱ, and random stratification were performed according to the type of operation, then divided into aggressive warming group and routine group. All the patients were covered with the warming blanket at the lower extremities and abdomen. Fluid warming was used in both groups. Separately, aggressive warming group used the forced-air warming right after the patients entering the room to keep a final target core temperature≥36 ℃. However, in the routine group, intraoperative forced-air warming was used only when patient's core temperature decreased to less than 35 ℃ by turning off the warmer when the temperature reached 35.2 ℃ and switched to routine method. Nasopharyngeal temperatures of patients in two groups were recorded at 5 min after induction of anesthesia (T1), the beginning of the operation (T2), 60 min (T3), 120 min (T4), 180 min (T5) after incision and the end of operation(T6). Serum cTnI levels in the two groups were measured at 5 min after induction, 12, 24 h and 48 h after operation. The changes of temperature and serum cTnI were compared between two groups. Postoperative adverse events such as arrhythmia(including atrial fibrillation, supraventricular tachycardia, frequent ventricular premature), anastomotic fistula and lung abscess were also recorded. Results The core temperature in aggressive warming group was above 36 ℃ all the time, while in routine group, the temperature dropped to below 36 ℃ at the time point of T3, and was kept around 35 ℃ during the intraoperative period after T3. Eight patients in routine group experienced a period of hypothermia with the temperature <35 ℃ and used the rescue warming up. The concentrations of serum cTnI in aggressive warming group were significantly lower than those in the routine group at 24, 48 h after operation (P<0.05). The ratio of patients with postoperative serum cTnI elevation in aggressive warming group was significantly lower than that in routine group(14.3% vs 34.9%, P<0.05). Aggressive warming group also had lower rate of arrhythmia and anastomotic fistula (P<0.05) . Conclusions Aggressive warming can avoid the occurrence of hypothermia during the radical resection of esophageal carcinoma and prevent the elevation of serum troponin I after operation. Key words: Esophageal carcinoma; Radical resection; Body temperature protection; Troponin I