The Influence On QTc Interval Prolongation By Cisatracurium Administration And Laryngeal Mask Airway Insertion During Anesthetic Induction

Objectives:A large number of incentives can lead to QTc interval prolongation during perioperative period,such as gender disparity,advanced age,electrolytical abnormalities and certain drugs.There are clearly clinical researches that the QTc interval can be prolonged during general anesthesia or spinal anaesthesia.The use of laryngoscopy,tracheal intubation and the use of some anesthesia drugs can also cause QTc interval prolongation.But the occurrence of QTc interval prolongation during anesthetic induction of non-depolarization muscle relaxant cisatracurium administration and the effects of Laryngeal Mask Airway insertion(LMA)on QTc interval in this setting are unknown.The purpose of this study was to observe the effect of the non-depolarizing muscle relaxants-cisatracurium,and the Laryngeal Mask Airway insertion on QTc interval during anesthetic induction.Methods:After approval by the ethics committee of The First Hospital of Jilin University,150 female patients,aged between 20 to 65 yr,with body mass index(BMI)<30 Kg/m2,of American Society of Anesthesiology(ASA)status I or II before operation,who were scheduled for elective hysteroscopic surgery under general anesthesia at First Hospital of Jilin University,were randomly devided into either cisatracurium administration group(n =75)or no cisatracurium administration group(n =75).In statistical analysis,patients who used vasoactive drugs during anesthesia induction were excluded from the final group.Finally,the group C consisted of 45 patients,and the group NC included 43 patients.A 12-lead Holter ECG was connected in the ward before going to operating room,and each patient's ECG was continuously recorded from this point until 1 minute after LMA insertion.The patients were monitored with noninvasive blood pressure,electrocardiogram and pulse oxygen saturation after admission.In the cisatracurium group,QTc intervals were recorded in the ward(T0),just entering the operation room(T1),after 15 minutes' rest(T2),1 minute after propofol and fentanyl intravenous injection(T3),1 minute after cisatracurium administration(T4),2 minutes after cisatracurium administration(T5),and 1 minute after LMA insertion(T6).The time points of QTc interval recorded in group NC were respectively in the ward(t0),just entering the operation room(t1),after 15 minutes' rest(t2),1 minute after propofol and fentanyl injection(t3),2 minutes after propofol and fentanyl injection(t4),3 minutes after propofol and fentanyl injection(t5),and 1 minute after LMA insertion(t6).Meanwhile,systolic blood pressure(SBP),diastolic blood pressure(DBP),mean arterial pressure(MAP),the heart rate(HR),and pulse oxygen saturation(Sp O2)were recorded at different time points in two groups respectively.Results:In cisatracurium group,QTc interval was significantly prolonged compared to the baseline values after arrival in the operating room(T1 vs T0: 451.6 ± 32.5 vs 417.9 ± 27.9 ms,p <0.001),and significantly decreased after 15 minutes' rest(T2: 432.4 ± 31.4 ms,p =0.045);After propofol and fentanyl injection,QTc interval prolonged again(T3: 459.7 ± 23.8 ms,p <0.001),but shortened after cisatracurium injection(T4: 440 ± 34.5 ms,p =0.024).In no cisatracurium group,the change of QTc interval at t0-t3 time points was similar to that in cisatracurium group.The comparison between the two groups revealed that cisatracurium administration had no effect on QTc interval during anesthesia induction;QTc intervals were not significantly changed by LMA insertion whether cisatracurium was employed or not.Conclusions:QTc interval is significantly prolonged after patients entering the operation room,and after propofol and fentanyl injection.Cisatracurium administration and Laryngeal Mask Airway insertion have no effect on QTc interval during anesthesia induction.