Impacts Of Sevoflurane At Different Concentrations On QTc Interval And QT Dispersion In Elderly Patients Undergoing Laparoscopic Cholecystectomy

Objective:To investigate whether the effects of sevoflurane at different concentrations on QTc interval and QT dispersion in elderly patients during elective laparoscopic cholecystectomy.Methods:Totally 120 elderly patients treated with laparoscopic cholecystectomy in the way of general anesthesia in the First Hospital of Shanxi Medical University were randomly assigned to four groups.The maintenance of anesthesia was adopted with inhalation of1.5%sevoflurane（A group）,2.0%sevoflurane（B group）,2.5%sevoflurane（C group）and control group（D group）,30 cases each.Heart rate,mean arterial pressure and arterial partial pressure of CO₂ were recorded as follows:before induction（T₀）,before pneumoperitoneum（T₁）,30 min after pneumoperitoneum（T₂）,5 min after the end of pnumoperitoneum（T₃）,at the moment of extubation（T₄）,at the time of leaving operating room（T₅）.Arterial blood gas analysis of different times are used to monitor the follows indices:serum potassium concentration,glucose,potential of hydrogen and partial pressure of carbon dioxide in artery.QT,QTc,QT dispersion and QTc dispersion was measured in all patients by chest leads electrocardiogram.The changes of QT,QTc,QT dispersion and QT dispersion in 4 groups were compared.Results:QT,QTcB and QTcF in C group were significantly higher than those in D group at T₁ and T₂（P<0.05）,these was no apparent difference in QT,QTcB and QTcF between the other groups（P>0.05）.QT dispersion and QTc dispersion at T₂ and T₃ were statistically higher than those at T₀ in each group,but T₃ was lower than T₂,these were no obvious differences in interaction between groups and time points.Conclusion:Under combined inhalation anesthesia,the maintenance of 1.5%～2.5%sevoflurane has no significant influence on QT dispersion,QTc dispersion.however,QT and its emendation maybe are prolonged under 2.5%sevoflurane.