[Recovery of neuromuscular block after continuous infusion of cisatracurium in patients with renal dysfunction]

Study of the recovery of neuromuscular block after continuous infusion of cisatracurium in patients with renal dysfunction.

Prospective case-control study.

Forty adult patients scheduled for urological surgery were assigned to two groups according to the creatinine clearance (CC) as a measure of the renal function: group IR (CC < 60 mL.min-1) or group NR (CC > or = 60 mL.min-1).

After premedication with hydroxyzine, anaesthesia was induced with propofol, sufentanil and cisatracurium (0.15 mg.kg-1), and maintained using isoflurane, sufentanil and a continuous infusion of cisatracurium (0.12 mg.kg-1.h-1) adjusted for maintained a post-tetanic count < or = 5. Neuromuscular transmission was monitored at the adductor pollicis using accelerography (TOF Gard). Onset and recovery times in both groups were compared using Student's t test.

Infusion time and total dose of cisatracurium were comparable in both groups. Onset times were 3.9 +/- 0.8 min and 3.5 +/- 0.6 min in groups IR and NR respectively. After the infusion, the time to train-of-four ratio of 0.8 were not different in both groups: 77 +/- 18 min (group IR) and 73 +/- 13 min (group NR). However, the spontaneous recovery intervals 25%-75% were delayed in group IR (20 +/- 9 min vs 14 +/- 5 min p < 0.05).

There are minor differences in the pharmacodynamics of cisatracurium between patients with normal or impaired renal function. Nevertheless, a marked interindividual variability in the recovery parameters was observed in patients with renal dysfunction.