RESUMO
Objective:To investigate the dose of intravenously infused cisatracurium for the maintenance of deep neuromuscular blockade during thoracic surgery.Methods:Patients of American Society of Anesthesiologists physical status Ⅰ or Ⅱ, aged 18-64 yr, scheduled for elective thoracic surgery under general anesthesia, were studied.The patients were connected to a muscle relaxation monitor after entering the operating room.After the completion of muscle relaxant calibration and anesthesia induction, cisatracurium was intravenously infused at a constant rate to maintain deep neuromuscular blockade (post-tetanic count [PTC]≤5 ). The infusion rate was calculated by modified Dixon up-and-down method.The first patient received cisatracurium at 0.12 mg·kg -1·h -1.If the PTC was 0 or was maintained≤5 continuously, the infusion rate was decreased 0.01 mg·kg -1·h -1 in the next patient, until PTC was >5 during operation.The mean dose for the patient was used as initial dose.Then the infusion rate was increased/decreased by 0.005 mg·kg -1·h -1.The 95% effective dose of cisatracurium (ED 95) was the median of 6 thresholds. Results:A total of 22 cases completed the study.The ED 95 of continuous intravenous infusion of cisatracurium for the maintenance of deep neuromuscular blockade was 0.108 mg·kg -1·h -1(95% confidence interval 0.105-0.125 mg·kg -1·h -1). Conclusion:The dose of intravenous infusion of cisatracurium for the maintenance of deep neuromuscular blockade during thoracic surgery is 0.108 mg·kg -1·h -1.
RESUMO
Objective To investigate continuous infusion and inermittent injection of cisatra-curium for deep neuromuscular blockade during laparoscopic surgery and to compare the effectiveness and safety.Methods Sixty ASA Ⅰ or Ⅱ patients,aged from 18 to 65,undergoing selective laparo-scopic gastrointestinal surgery with general anesthesia were randomly divided into 2 groups:group A (n =30)received cisatracurium 0.1 5 mg/kg for intubation,and then continuous infusion of cisatra-curium with micropump at an original rate of 0.2 mg·kg-1 ·h-1 when post tetanic count (PTC)≥3;group B(n =30)was given cisatracurium 0.1 5 mg/kg for intubation,and then intermittent infusion of cisatracurium of 0.05 mg/kg when PTC≥ 3.The cisatracurium consumption,duration of neuro-muscular blocking agent used in group A from induction to the end of infusion and in group B from in-duction to the last infusion,satisfaction of neuromuscular blockade (grade 0-10)of the surgeons,the time of T1 recovered to 25%,75%,TOFr recovered to 0.7,0.9,fulfillment of tongue depressor test,the incidence of hyoxemia after extubation,pneumonia,atelectasis were recorded.Results In comparison with group B,the cisatracurium consumption in group A was significantly more (P <0.05),and the satisfaction of the surgeons was significantly higher at the beginning,1 h,2 h of the operation (P <0.05).The satisfaction of the surgeons respectively showing no significant differences between the two groups at the end of the operation.Recovery index (T1 from 25% to 75%),time of TOFr recovery to 0.7,0.9 in group A was increased,but not statistically.Two patients (7.1%)in group A had hyoxemia after extubation while 1 (4.2%)in group B,the incidence rate was not signifi-cant;3 patients (10.7%)in group A was unable to perform sustained tongue depressor test while 4 (1 6.7%)in group B,the incidence was not significant;all of the patients did not suffer pneumonia and atelectasis.Conclusion Continuous infusion cisatracurium during laparoscopic procedures for deep neuromuscular blockade is effective and safe.The dose of cisatracurium is bigger,and muscular relax-ation would be deeper compared to intermittent infusion.Continuous infusion may prolong the working time of muscle relaxant,but have on influence on the residual effect of muscle relaxant.