Rocuronium Isoflurane

In 113 patients undergoing general anesthesia, intravenous midazolam 15 mg slowed recovery of the twitch height after vecuronium and atracurium compared with diazepam. The recovery index was not altered (162). However, in another study in 20 patients, midazolam 0.3 mg/kg did not affect the duration of blockade, recovery time, intensity of fasciculations, or adequacy of relaxation for tracheal intubation produced by suxamethonium 1 mg/kg, nor the duration of blockade and adequacy of relaxation for tracheal intubation produced by pancuronium 0.025 mg/kg in incremental doses until 99% depression of muscle-twitch tension was obtained (161). Furthermore, in 60 patients undergoing maintenance anesthesia randomly assigned to one of six regimens (etomidate, fentanyl, midazolam, propofol, thiopental plus nitrous oxide, or isoflurane plus nitrous oxide), midazolam did not alter rocuronium dosage requirements (165). 

Olkkola KT, Tammisto T. Quantifying the interaction of rocuronium (Org 9426) with etomidate, fentanyl, midazolam, propofol, thiopental, and isoflurane using closed-loop... 

A 35-year-old man developed recurrent respiratory depression after being given alfentanil 0.0125 mg/kg for vitreoretinal surgery (5). General anesthesia was induced with a combination of propofol, rocuronium, and alfentanil, subsequent inhalation of isoflurane, and three additional doses of alfentanil (total 0.04 mg/kg over 2 hours). The pulse oxygen saturation fluctuated and was as low as 89% 180 minutes after extubation. 

Both desflurane and sevoflurane significantly increase the neuromuscular blocking effects of rocuronium compared with isoflurane or propofol (20,21). 

Lowry DW, Mirakhur RK, Carrol MT. Time course of action of rocuronium during sevoflurane, isoflurane or i.v. anaesthesia. Br J Anaesth 1998 80 544. 

Wulf H, Ledowski T, Linstedt U, Proppe D, Sitzlack D. Neuromuscular blocking effects of rocuronium during desflurane, isoflurane, and sevoflurane anaesthesia. Can J Anaesth 1998 45(6) 526-32. 

Both desflurane and sevoflurane significantly increase the neuromuscular blocking effects of rocuronium compared with isoflurane or propofol (41,42). The effective doses of rocuronium for 50% depression of single twitch height were 95,120,130, and 150 pg/kg for desflurane, sevoflurane, isoflurane, and propofol respectively. There were no differences in recovery profiles between the four drugs using equieffective doses. Desflurane, sevoflurane, and to a lesser extent isoflurane, also potentiated the neuromuscular blocking effect of cisatracurium by 30% compared with propofol (43,44). 

The infusion requirements of rocuronium necessary to maintain twitch depression were reduced by 40% during anesthesia involving isoflurane (24). In another study in 60 patients undergoing maintenance anesthesia, isoflurane plus nitrous oxide anesthesia reduced the dosage requirement of rocuronium by 35-40% (25). 

Shanks CA, Fragen RJ, Ling D. Continuous intravenous infusion of rocuronium (ORG 9426) in patients receiving balanced, enflurane, or isoflurane anesthesia. Anesthesiology 1993 78(4) 649-51. 

Cooper RA, Maddineni VR, Mirakhur RK, Wierda JM, Brady M, Fitzpatrick KT. Time course of neuromuscular effects and pharmacokinetics of rocuronium bromide (Org 9426) during isoflurane anaesthesia in patients with and without renal failure. Br J Anaesth 1993 71(2) 222-6. 

Clinically important, potentially hazardous interactions with aminoglycosides, clindamycin, cyclopropane, enflurane, halothane, isoflurane, methoxyflurane, piperacillin, rocuronium... 

Reid JE, Breslin DS, Mirakhur RK, Hayes AH. Neostigmine antagonism of rocuronium block during anesthesia with sevoflurane, isoflurane or propofol. Can JAnaesth (2001) 48, 351-5. 

Bock M, Klippel K, Nitsche B, Bach A, Martin E, Motsch J. Rocuronium potency and recovery characteristics during steady-state desflurane, sevoflurane, isoflurane or propofol anaes-diesia. BrJ Anaesth (2000) 84, 43-7. 

A 71-year-old woman received a standard bowel preparation consisting of oral erythromycin and neomycin (a total of 3 g). Surgery was postponed for one day and she received a second similar bowel preparation pre-operatively. Anaesthesia was induced with sufentanil and etomidate and maintained with isoflurane and sufentanil. Rocuronium (total dose of 60 mg over 2 hours) was used to facilitate tracheal intubation and maintain muscle relaxation. Despite clinical appearance of a reversal of the neuromuscular blockade by neostigmine 3.5 mg and glycopyrrolate 400 micrograms, the patient complained of dyspnoea and required reintubation twice. The effects of additional doses of neostigmine were inconsistent and the use edrophonium 50 mg or calcium chloride 500 mg intravenously did not result in an improvement. ... 

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