Effects Of Sevoflurane After Priming On Onset Time Of Neuromuscular Blockade Induced By Cisatracurium

ObjectiveCisatracurium already has been introduced into clinical practice as a new intermediate-duration nondepolarising neuromuscular blocking drug. It is the first choice for elderly patients and patients with renal, hepatic or cardiac failure.It has so many advantages with only one shortcomings:slow onset. So this issue was performed to study whether induced by sevoflurane could shorten the onset time of cisatracurium after priming, and observe the condition of intubation.So we can make an objective assessment about the clinical feasibility and advantages of induction by sevoflurane combined priming before cisatracurium intubation.Methods60 ASA physical statusⅠandⅡpatients undergoing elective surgery requiring general anesthesia were enrolled and randomly divided into 3 groups, Group S: sevoflurane inhalation after priming;Group P:propofol infusion after priming;Group C: no priming. There are 20 patients in one group.30 minutes before surgery,regular preanesthetic medication was given to evergy patient:oral diazepam 10mg and intramuscular atropine 0.05mg/kg. After arriving the operating room,Ringer's solution was infused 500ml at a speed of 10ml/Kg·h. Anesthesia was induced with 3μg/kg fentanyl and propofol TCI infusion, target concentration 4μg/ml.When the patients lost confusion and eyelash reflex,stop infuse and breathed 4L/min oxygen by mask through manual control. vecuronium was given to facilitate endotracheal. Maintenance of end-tidal carbon dioxide partial pressure was 28-35mmHg.After mechanomyography calibrating, Group S and Group P received cisatracurium 0.01 mg/Kg(20%ED95):2ml, Group C received normal saline(2ml) in 2S. During 3 minutes primig interval,mechanomyography assessed the neuromuscular function of the adductor pollicis with train-of-four supramaximal impulses TOF and T1. After the priming interval,Group S and Group P received 0.14mg/Kg(3ED95-Priming Dose),and Group C received 0.14mg/Kg(3ED95) for intubation. Control breathing through mask :tidal volume 8-10ml/Kg and oxygen flow 4L/min.Group S inhaled sevoflurane concentration maintained at 8%-3%, end-tidal MAC value was maintained at 2.0-2.5.Group P and Group C were TCI infused propofol:the target plasma concentration 3μg/ml. Trachea was intubated when the amplitude of the first twitch (T1)decreased to 0, then the trial was completed. Record hemodynamic changes, TOF values in priming interval,onset time and evaluation of intubation conditionsResultsIn this study,60 patients were enrolled in the original. In Group C,1 case was removed from the trial because his blood pressure was elevated at 152/99mmHg after using ephedrine 6 mg to prevent hypotension of systolic blood pressure less than 80mmHg.There was 1 patient used ephedrine 6mg one time in Group P and 1 patient used atropine o.3mg one time.There were no significant differences among three groups of age,BMI sex ratio,albumin and hemoglobin(P>0.05). Hemodynamic parameters were no statistically significant difference(P>0.05) except T3:SBP3 and HR3 in Group S were higher than that in Group P and Group C(P<0.01). The onset time of neuromuscular blockade in Group S and Group P was significantly shorter than Group C(P<0.01).The intubation condition was similar in each group(P>0.05). All the patients were intubated successfully one time.TOF value of priming interval in priming groups(Group S and group C) showed downward trend.The minimum TOF value in 3 minutes was at 3 min.There were no case that TOF value lower than 96% during priming interval.Conclusion1. Induced by inhalation of sevoflurane can short the onset time of cisatracurium (3ED 95 0.15mg/Kg) after priming with hemodynamic stability.2. Priming dose 20%ED95 (0.01mg/Kg) of cisatracurium and priming interval for 3 minutes can short the onset time of 3ED95(0.15mg/Kg) cisatracurium.3. TOF value in priming interval of priming dose 20%ED95 (0.01mg/Kg) of cisatracurium isn't lower than 96%.So it is safe for clinical practice.