PHARMACOKINETICS OF ROCURONIUM BROMIDE IN PATIENTS WITH AND WITHOUT RENAL-FAILURE

We studied the onset and duration of action and pharmacokinetics of ro curonium bromide during anaesthesia with nitrous oxide, fentanyl and i soflurane after a single bolus dose of rocuronium (0.6 mg kg(-1)) in n ine patients with chronic renal failure requiring regular haemodialysi s, and in nine healthy control patients. Blood samples were collected over 390 min and concentrations of rocuronium and its putative metabol ites measured using HPLC. Onset time for maximum block and duration of clinical relaxation (DUR(25)) were 61 (SD 25.0) s and 65 (16.4) s, 55 (26.9) min and 42 (9.3) min, respectively, for patients with and with out renal failure. The time for train-of-four ratio to return spontane ously to 0.7 was 99 (41.1) min and 73 (24.2) min, respectively, in the two groups. None of these differences was significant. The pharmacoki netic data were best described by a three-exponential equation. There were significant differences between patients with and without renal f ailure in the rates of clearance (2.5 (1.1) mL kg(-1) min(-1) and 3.7 (1.4) mL kg(-1) min(-1), respectively) and the mean residence times (9 7.1 (48.7) min and 58.3 (9.6) min) (P < 0.05). The differences in othe r kinetic parameters were not significant.