Comparision of acceleromyography and kinemyography monitoring methods during recovery period of neuromuscular block

In general anesthesia neuromuscular blocking agents are used for the purpose of intubation and muscle relaxation. Traditionally, the degree of neuromuscular block during and after anesthesia is assessed by clinical criteria only and intubation or extubation decision is given by anesthesiologists subjective observations. Postoperative residual curarization after administration of neuromuscular blocking drugs is a very important factor in increasing morbidity and mortality. The only proposed objective method for detecting residual neuromuscular block is quantitative neuromuscular monitoring.17-19 In our study, we compared acceleromyography, the most commonly used method of neuromuscular monitoring, with kinemyography for the recovery parameters of anesthesia. After approval of our institutional ethics committee and obtaining written consent, 46 ASA status I and II patients aged 19-65, scheduled for elective surgery under general anesthesia with both arms open were studied. The patients in whom prolonged surgery necessitated additional dose of neuromuscular blockers or delayed spontaneous recovery indicated use of reversal agents and in whom either acceleromyographic, kinemyographic, or both methods of data acqusition was defective were excluded. After admission to the operating room each patient was monitored with EKG, SpO2 and NIBP. After standardized induction using midazolam, fentanyl and propofol, the method of acceleromyography (TOF-SX, Organon) was set up to the left arm and the method of kinemyography (Datex NMT, GE) was set up to the rigt arm of patients for neuromuscular monitoring. Rocuronium 0.6 mg/kg was administered under single twitch pattern of neuromuscular monitoring. After attaining 95% twitch depression (T1/T0 5%) the patients were intubated. After intubation neuromuscular monitoring continued with train of four (TOF) pattern every 15 seconds and the times for TOF neuromuscular recovery parameters of TOF 25, TOF 50, TOF 75, TOF 90 and TOF recovery index (TOF25-75) were recorded. All data were statistically analyzed utilizing Bland Altman method which is based on regression analysis for comparing similarities. In our study we concluded that the methods of acceleromyography and kinemyography for neuromuscular monitoring are interchangeable for the recovery parameters of neuromuscular block. We believe that in addition to acceleromyography, kinemyography can also be safely used to determine postoperative residual curarization.