[The efficacy and safety of priming principle with pipecuronium]

The authors evaluated the cumulative dose response of pipecuronium under isoflurane anesthesia, and the efficacy as well as safety of priming principle in 52 patients who underwent elective surgery. The ED95 of pipecuronium was 34.24 +/- 5.34 micrograms.kg-1 in 10 patients and 70 micrograms.kg-1 (not equal to ED95 x 2) was used as total dose (T). The 42 patients were divided to receive either no prime or, 5%, 10%, 15% or 20% of T as a prime followed 5 minutes later by the remaining (intubating) dose. The muscle weakness in awake patients was determined after the priming doses by examining several clinical symptoms and by evaluating the effect of intubating doses on neuromuscular blockade. The priming using 10% of T provided rapid intubating conditions. However, the priming dose caused a significant incidence of symptoms of muscle weakness. Therefore, the priming principle should be used with caution.