Neuromuscular blockers (NMB) are very important adjuvant to generalanesthesia, rocuronium bromide and cisatracurium besylate are considered relatively recently introduced non-depolarizing muscle relaxants. This study evaluated the enhancement of cisatracurium and rocuronium induced neuromuscularblock, by constructing dose-effect curves in 80 patients during anesthesia with 2 MAC sevoflurane or total i.v. anesthesia (TIVA). Acceleromyography (TOF-Guard)and train-of-four (TOF) stimulation of the ulnar nerve were used (2 Hz every 15 s). Cisatracurium and rocuronium were administered in increments until depression ofT1/T0 >95% was reached. Depression of T1/T0 during sevoflurane was enhancedcompared with TIVA via propofol infusion. ED50 and ED95 values of both drugs were significantly lower than the values for TIVA. Recovery index 25–75% and time to a TOF ration of 0.70 were prolonged significantly by sevoflurane compared with TIVA. We conclude that the effects of rocuronium and cisatracurium are significantly enhanced during sevoflurane compared with propofol anesthesia and the recovery is slower. Hemodynamically, rocuronium and cisatracurium did not exert significant changes as detected via Bio-impedance, but the interaction of the relaxants and the anesthetic agents resulted in statistically significant decline in some hemodynamic parameters at certain periods which are not clinically significant and required no medications.