THE ONSET OF PIPECURONIUM FOLLOWING APPLICATION OF THE PRIMING PRINCIPLE

Pipecuronium bromide, a long acting non-depolarizing neuromuscular blo cking agent was administered to four groups of 10 patients using the p riming technique. The effects of the combination of two different prim ing doses (0.01 or 0.015 mg kg(-1)) given at two different time interv als (3 or 4 min) before the 'main' intubating dose (0.07 or 0.065 mg k g(-1)) were investigated. Onset times were recorded and the intubation conditions were scored and compared with a group of patients receivin g the same total amount of pipecuronium (0.08 mg kg(-1)) in a single b olus injection. Intubating conditions at 90 s after administration of the intubating dose were found Po be significantly improved in all pri med groups but the onset times, evaluated using the response of the ad ductor pollicis muscle to a single twitch stimulation, were similar to that observed after the single bolus injection. The optimal priming c ombination is considered to be 0.01 mg kg(-1) of pipecuronium followed 3 to 4 min later by 0.07 mg kg(-1).