Secondary hyperparathyroidism shortens the action of vecuronium in patients with chronic renal failure

The authors studied the duration of action of vecuronium in 15 patients with normal renal function and 40 patients with chronic renal failure to evaluate the effect of secondary hyperparathyroidism on the action of vecuronium. The patients were divided into four groups: 15 patients with normal renal function (Group A); nine patients with chronic renal failure who did not need haemodialysis (Group B); 15 anephric patients who did not require parathyroidectomy (Group C); and 16 anephric patients who underwent parathyroidectomy because of severe secondary hyperparathyroidism (Group D). The ratio of the height of the first twitch (T1) to the baseline value before vecuronium administration was measured by an electromyogram. Baseline T1 was obtained after anaesthesia induction with thiamylal iv. The time to 10% recovery of the first twitch (REC 10) after administration of vecuronium 0.12 mg.kg-1 iv was measured in each group. Anaesthesia was maintained with isoflurane and nitrous oxide in oxygen, and supplemented with fentanyl iv. Patients in Group D showed shorter REC 10 (51 +/- 4 min) than those in Groups B (71 +/- 6 min) and C (80 +/- 10 min) (P < 0.05), but similar REC 10 to patients in Group A (37 +/- 4 min). These results suggest that the duration of action of vecuronium in anephric patients with secondary hyperparathyroidism is shorter than in those without secondary hyperparathyroidism.