Effect of bolus injection of 20 ml saline with arm elevation on the onset time of vecuronium administered via a peripheral vein: a randomised controlled trial.

We investigated whether a bolus injection of 20 ml saline with arm elevation might shorten the onset time of vecuronium administered via a dorsal hand vein. Thirty patients were randomly allocated to the bolus saline group or control group. General anaesthesia was induced and maintained with remifentanil and propofol. Vecuronium 0.1 mg.kg(-1) was administered to all patients, followed in the treatment group by bolus injection of 20 ml saline and arm elevation. Response to train-of-four stimulation was measured by acceleromyography at the adductor pollicis muscle. The mean (SD) lag time was 47.2 (14.5) s in the bolus saline group and 67.9 (12.2) s in the control group (p = 0.0002). The time to 95% block of T1 was 104.6 (29.9) s in the bolus saline group and 128.3 (15.8) s in the control group (p = 0.011). Bolus saline injection results in shortened lag time and onset time of neuromuscular block with vecuronium.