COMPARISON OF THE INFUSION REQUIREMENTS AND RECOVERY PROFILES OF VECURONIUM AND CISATRACURIUM 51W89 IN INTENSIVE-CARE UNIT PATIENTS

The selection and administration of neuromuscular blocking (NMB) drugs in intensive care unit (ICU) patients remain controversial. We compar ed the dose-response and recovery pharmacodynamics of a new intermedia te-acting NMB drug, cisatracurium besy-late, to the intermediate-actin g NMB drug, vecuronium (VEC), in a prospective, randomized, double-bli nd, multicenter study in critically ill adults. After informed consent , 58 mechanically ventilated ICU patients from five medical centers we re randomized to receive either cisatracurium or VEC. Fifty-four of th e 58 patients received NMB drugs before entering this study but demons trated at least partial recovery (greater than or equal to one twitch) in the train-of-four (TOF) response before initiation of the NMB stud y drug. NMB drug infusion was titrated by peripheral nerve stimulation to maintain at least one twitch in the TOF response. NMB drugs were i nfused for 1-5 days. After discontinuation of NMB drug infusion, recov ery of neuromuscular transmission was monitored with an accelerometer. NMB drug infusion for 28 cisatracurium patients averaged 2.6 +/- 0.2 (mean +/- SEM) mu g . kg(-1). min(-1) with a mean duration of 80 +/- 7 h. After discontinuing cisatracurium administration, recovery to 70% TOF ratio averaged 68 +/- 13 min. The mean infusion rate for 30 VEC pa tients was 0.9 +/- 0.1 mu g . kg(-1). min(-1) with a mean duration of 66 +/- 12 h. Neuromuscular recovery after VEC averaged 387 +/- 163 min , which was significantly longer (P = 0.02) than that after cisatracur ium. Prolonged recovery of neuromuscular function after discontinuatio n of NMB drug infusion (identified by the primary investigator at each medical center) was reported in two cisatracurium patients and 13 VEC patients (P = 0.002), and occurred despite the routine use of neuromu scular twitch monitoring. Seven VEC and one cisatracurium patients die d during the infusion of study drug or within 48 h after discontinuati on of the NMB drug infusion. In summary, we found recovery of neuromus cular function after discontinuation of NMB drug infusion in ICU patie nts is significantly faster with cisatracurium than with VEC. In addit ion, routine neuromuscular monitoring was not sufficient to eliminate prolonged recovery and myopathy in ICU patients.