Effects Of Sevoflurane Inhalational Anesthesia On Cardiac Troponin â…  In Patients Undergoing Abdominal Surgery

Myocardium is sensitive to ischemia and anoxemia for demanding high level of oxygen, which is liable for myocardial damage particularly during the perioperative period. Cardiac troponins I (cTn I) appears early in the plasma after myocardial damage and the duration of cTn I elevation is long. It is considered to be highly specific and sensitive markers of myocardial cell damage during the perioperative period. It is used to evaluate the protective effects on the myocardial cell and judge the prognosis of patients, which is worthy of expansion as serum marker. Compared with propofol, sevoflurane is a new kind of inhalation anesthetic agent, which is stable for induction and maintenance, and it can provide light suppression of circulation, stable hemodynamics, and make the patients coming around rapidly.Objective: To explore the effects of inhalational anaesthesia with sevoflurane on cTn I during the perioperative period, comparing with total intravenous anesthesia with propofol in the abdominal operation-radical gastrectomy for cancer, and the mechanism of sevoflurane-induced cardioprotection.Methods: Forty patients (ASAⅡ-Ⅲ), aged 39 to 67 years, weight 47 to 75 kg, scheduled for selected radical gastrectomy under general anaesthesia were recruited from the First Hospital of Jilin University. Patients were randomly classified into two groups: (i) individuals with sevoflurane anaesthesia (group S, n=20); (ii) individuals with propofol anaesthesia (group P, n=20).The individuals with coronary heart disease, difficult for intubation, central nervous system disease, septemia, hepatosis, renal dysfunction, dyshormonism were ruled out. The time of fasting solid was more than 12 hours, and fluid was more than 4 hours. Atropine 0.5mg was intramascular injected at 30 minutes before operation. After opening the venous channel, Ringer lactate solution and 6% hydroxyethyl starch with the proportion of two to one were infused. Pure oxygen was given for 3 minutes with mask to Group S 2 or 3 minutes later following anaesthesia induction with Midazolam 0.05~0.06mg/kg to each group, and then Volatihzation pot was opened with 0.5% sevoflurane,of which concentration adjusted for inspired rate 3 times added 0.5% till 3%.Fentanyl 3~4μg/kg and vecuronium 0.1mg/kg were injected simultaneously. Respirator was connected following tracheal intubation for control mandatory ventilation(CMV) with tidal volume(VT)8~10ml/kg,respiration rate(RF)12~15/min, inspiratory/expiratory(I:E)1:2. End-tidal carbon dioxide partial pressure (PETCO2) maintained 35~40mmHg with 1~3%sevoflurane persistently inhalated. 1.5~2mg/kg propofol, fentanyl 3~4μg/kg and vecuronium 0.1mg/kg was given to group P. Tracheal intubation was followed denitrificatiing and oxygen storaging and the respiration parameter was the same as group S. Propofol 4~8μg/kg/h was persistently pumped. Vecuronium was administered discontinuously and Remifentanil 0.1~0.2μg/kg/min was given persistently according to blood pressure and heart rate. Fentanyl 0.1 mg was added again before closing abdomen. Propofol, sevoflurane and remifentanil were withdrawed after operation. Noninvasive systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR) and pulse oxygen saturation (SPO2) were monitored and recorded at the time of before anaesthesia (T1), after induction (T2), the beginning of the operation (T3) and the end of the operation (T4). 5ml venous blood was collected at T1 to T4, 1 day and 3 days after the surgery (T5, T6), and the samples were centrifuged at the rotation of 3000r/min for 10 minutes. The supernatant was collected and stored in the freezer at temperature below -30℃. The cTn I was tested by radioimmunoassay.Results: 1. changes of hemodynamics:①SBP and DBP both decreased after induction(T2) in two groups, but the difference of Group P was obvious(P<0.05), which represented the statistical significance. In Group S, SBP decreased after induction either, but there was no statistical significance. In both group, SBP and DBP at T3 and T4 was no marked difference compared with T1 The difference between two groups was small and had no statistical significance.②Heart rate was obviously lower at T1 than To(P<0.05)in Group P. However, there was no significant difference at other time in two groups and there was no statistaical significance between Group P and Group S.2. The level of cTn I had the increasing trend after induction (T1) compared with preanaesthesia (T0) in both of two groups. cTn I increased obviously at T5(P<0.05),however it had the descending trend at T6 ,whereas the level of cTn I at T6 was still higher than T0. The level of cTn I had no significant difference at each point in Group S compared with T0. The level of cTn I of Group P at T2 and T5 was significantly higher than that of Group S(P<0.05), which had the statistical significance.Conclusions: SBP and DBP decreased after induction in both of two groups, and compared with Group S, SBP and DBP were lower in Group P. It showed that the decrease of blood pressure was dose-dependent induced by inhalational anaesthesia with sevoflurane and intravenous anesthesia with propofol, moreover, the suppression of circulation induced by propofol was more obvious than sevoflurane. The level of cTn I of two groups at each point was all higher than preanaesthesia. Compared with Group P, there is significantly less release of cTn I in Group S. It suggests that both of sevoflurane and propofol have the effects of cardiac damage during the perioperative period, but the effect of alleviating cardiac damage of sevoflurane was better than propofol during the perioperative period.