Clinical Study Of Reasonable Dosage Of Cisatracurium For Pre-injection In The Elderly

Objective: To find a reasonable pre-injection dose of cisatracurium, wecompared onset time and intubation condition of cisatracurium in the elderlyusing four different dose of pre-injection of cisatracurium.Method:75elderly patients with age frome65to75years and ASA Ⅰ～Ⅱwere enrolled in this study. Inclusion criteria included several conditions asfollow: examination of heart, lung, liver and kidney before surgery werenormal; there were no history of metabolic disease, no malnutrition or obesity,no hypertension, no cerebral infarction, no obesity or other medicaldiseases;there were no water and electrolyte metabolism disorder, no acid-baseimbalance. Exclusion criteria included as follow: there were trauma, surgery,puncture history of the parts used for muscle relaxant monitor the last threemonths; there was a history of neuromuscular disease or the small jointsdisorder; patients took drugs affecting muscle relaxants preoperative, such asaminoglycoside antibiotics, multi-stick streptozotocin, lincomycin, phenytoin,potassiumion drugs and anticonvulsants. Patients were randomly divided into5groups and every group contain15patients. Group Ⅰwas the blank controlgroup, pretreatment with3ml of normal saline, Ⅱ~Ⅴgroup preinjection ofcisatracurium0.015mg/kg,0.020mg/kg,0.025mg/kg,0.030mg/kgrespectively. The remaining cisatracurium was injected after3minutes and thetotal dose of cisatracurium were all15mg/Kg(3×ED95). All patients werefasting water preoperative8hours and were monitored noninvasive bloodpressure, ECG and pulse oximetry (SpO2). After face mask oxygen for fiveminutes, intravenous midazolam0.05mg/kg, and subsequently priming dose ofcisatracurium, we closely observed the patient’s breathing, swallowing, rising head, cough and extending tongue after injection3minutes. If there werebreathing difficulty, anxiety and fear, we would give assisted respiration andinducing drugs immediately. Patients would forget the bad memories ofdiscomfortable process because of pre-given midazolam.3minutes later,etomidate0.3mg/kg, fentanyl3-5ug/kg and the remaining cisatracuriumammonium were intravenous given. When patient was sleep, we monitored theneuromuscular function of adductor pollicis muscle by muscle relaxant monitor.Stimulation current was0.2ms of single-phase square wave,40mA,2Hz of thefour clusters of stimulation, each TOF stimulus interval15s.when Trachealintubation when the number of adductor pollicis muscle contract reaction afterTOF was not more than2, we would perform trachea cannula, record the onsettime and grade intubating conditions. We also recorded mean arterial pressure(MAP), heart rate (HR), pulse oximetry when preinjection, three minutesafter the preinjection, trachea cannula,1minute after intubation and3minutesafter intubation.Results: Each trial group was significantly shorter (P<0.01) than controlgroup, however, there was no significant differences (P>0.05) of onset time orintubating conditons between group III, IV and V. There were1cases and2cases of breathing difficulty in group Ⅳ and Ⅴrespectively. No significantdifferences (P>0.05) of MAP and HR at any time in five groups wasexisted.Conclusion: Preinjection of cisatracurium could signifcantly decreaseonset time of cisatracurium in the elderly, however, there was no signifcantdifference in intubation condition. It is safe and effective of0.020mg/kgcisatracurium as preinjection dosage in the elderly.