Effects Of Aggressive Warming On Myocardial Injury In Patients Undergoing Radical Resection Of Esophageal Carcinoma

Background:Intraoperative hypothermia,defined as core temperature less than36°C during operation,is a common problem among surgical patients,also is a neglected problem.The risk of hypothermia is particularly high in patients who have had major or lengthy surgery?thoracic or abdominal surgery?,such as:radical resection of esophageal carcinoma.An incidence of hypothermia of 50%to 90%in some studies,has been reported.The incidence of inadvertent intraoperative hypothermia of Chinese surgical patients in Beijing who received general anesthesia was high,about 39.9%.At present,most hospitals in China do not take the body temperature as a routine test index,the awareness of body temperature protection is relatively weak.Only 10.7%of the patients were given perioperative active insulation measures.It is still to be explored whether the intraoperative enhancement of heat preservation can reduce the incidence of postoperative myocardial injury in patients with radical resection of esophageal carcinoma.The incidence of myocardial injury in noncardiac surgery is generally reported in8%of the patients,84.2%of them have no ischemic symptoms.In many cases,there is no obvious electrocardiographic ST-segment elevation,but the 30-day mortality rate in patients with myocardial injury can be as high as 10%.Cardiac troponin concentration is reported to be a more sensitive myocardial ischemia index that can recognize early myocardial injury.Myocardial injury related motality rate after surgery increase 3 times in patients with cardiac troponin T?cTnT?higher than 0.02?g/L,and when the concentration higher than 0.03?g/L,the rate can increase 9 times.Some scholars have reported that troponin T>0.03?g/L can be used as an independent predictor of perioperative myocardial injury.Van Waes recommended that cardiac troponin I?cTnI?>0.06?g/L can be used to define myocardial injury,and concluded that postoperative myocardial injury is an independent predictor of 30-day mortality after noncardiac surgery.VISION investigators found that the MINS?myocardial injury after noncardiac surgery?diagnostic criteria were an elevated postoperative hs-cTnT?0.02 to less than 0.065?g/L with an absolute change of at least 0.005?g/L or at least 0.065?g/L?.Our study based on esophageal carcinoma patients aged 45-80.Observations:1.Effects of aggressive warming on intraoperative temperature and cardiac troponin I.2.The value of a combined detection of troponin I and T in the diagnosis of myocardial injury after radical resection of esophageal carcinoma,and the effects of aggressive warming on myocardial injury.3.Effects of aggressive warming on the expression of perioperative inflammatory cytokines.To explore the middle-aged patients with esophageal cancer during anesthesia temperature management strategies and whether to reduce the related myocardial injury.Methods:1.Ninety patients undergoing elective radical resection for esophageal carcinoma were randomly divided into two groups:aggressive warming group and routine group?45 in each arm?.Nasopharyngeal temperatures of patients in two groups were recorded at 10min after induction of anesthesia?T₁?,the beginning of the operation?T₂?,60min?T₃?,120min?T₄?,180min?T₅?after incision and the end of operation?T₆?.Serum cTnI levels in the two groups were measured at 5min after induction,6-12,24and 48h after operation.The incidence rate of intraoperative and postoperative within48h severe arrhythmia,which comprise of atrial fibrillation,supraventricular tachycardia,frequent ventricular premature beats were recorded,anastomotic fistula and lung abscess were also recorded.2.Based on the results of the previous studies,the blood samples from 70 patients?35 in each arm?were completely re-analyzed to determine the concentration of hs-cTnT.The incidence of myocardial injury within 48 hours after surgery was calculated according to the following criteria.The primary outcome was myocardial injury,defined as elevated cTnI?>0.06?g/L?or elevated hs-cTnT?0.02 to less than 0.065?g/L with an absolute change of at least 0.005?g/L or at least 0.065?g/L?or both at any time point during 48 hours after the surgery.Secondary outcomes included:1)The incidence rate of severe arrhythmia intraoperative and postoperative within 48 hours.2)The incidence rate of hypoxemia and metabolic acidosis postoperative within 12 hours.3)The incidence rate of deep vein thrombosis or pulmonary embolism postoperative within 48hours.3.The blood samples of 70 patients?35 in each arm?in the second part were further tested for the levels of interleukin-6?IL-6?and interleukin-10?IL-10?.The differences between the two groups were analysed with the combination of the levels of IL-6,IL-10,the patients'thermal comfort score postoperative within 6 hours,the pain score postoperative within 48 hours,ICU stay time and hospital stay time.Results:1.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.The concentrations of serum cTnI in aggressive group were significantly lower than those in routine group at 24h,48h postoperatively?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?.2.Of the three patients receiving aggressive warming who experienced myocardial injury,two of the patients met both the cTnI and hs-TnT criteria for myocardial injury,while the third patient met only the hs-TnT criterion.Of the 11 patients from routine group who experienced myocardial injury,7 met both criteria for myocardial injury,3patients met only the hs-TnT criterion,and 1 patient met only the cTnI criterion.The incidence of myocardial injury postoperative within 48 hours was 8.6%?3/35?among aggressive warming group and 31.4%?11/35?among routine group?P<0.05?.The incidence of severe arrhythmia intraoperative and postoperative within 48 hours was 2.9%?1/35?and 25.7%?9/35?among aggressive warming group and routine group,respectively?P<0.05?.The incidence of hypoxia postoperative within 12 hours was 17.1%?6/35?among aggressive warming group and 40.0%?14/35?among routine group?P<0.05?.The incidence of metabolic acidosis postoperative within 12 hours was 20%?7/35?among aggressive warming group and 48.6%?17/35?among routine group?P<0.05?.The incidence of deep vein thrombosis or pulmonary embolism postoperative within 48 hours was 0%?0/35?among aggressive warming group and 2.9%?1/35?among routine group?P<0.05?.3.There was no significant difference in plasma IL-6 and IL-10 concentrations between the two groups at 6-12,24 and 48h after operation.The levels of IL-6 and IL-10 were not significantly different between the two groups.Compared with the routine group,the VAS score of 48 hours after operation in aggressive warming group decreased?P<0.05?,and the thermal comfort score postoperative within 6 hours in aggressive warming group was higher than that in routine group?P<0.05?.The postoperative ICU and hospital stay time in two groups had no significant difference.Conclusions:1.Aggressive warming can avoid the occurrence of hypothermia during the radical resection of esophageal carcinoma and prevent the elevation of serum troponin I postoperatively.2.The combined use of two kinds of troponin can improve the detection rate of myocardial injury after the radical resection of esophageal carcinoma.Aggressive warming can reduce the incidence of myocardial injury postoperative within48 hours.3.Compared with routine group,aggressive warming group did not inhibit the expression of inflammatory cytokines after the resection of the elderly patients with esophageal carcinoma.There is no direct correlation between myocardial injury and changes of postoperative inflammatory cytokines after operation.