RETRACTED: Post-tetanic count and train-of-four responses during neuromuscular block produced by vecuronium and infusion of nicardipine

Abstract

We have examined onset and recovery of neuromuscular block produced by vecuronium using either post-tetanic count (PTC), or the first twitch of the train-of-four (TOF) (T1/T0) and TOF ratio (T4/T1) during continuous infusion of nicardipine. Sixty adult patients were allocated to one of four groups of 15 patients each: nicardipine-PTC, nicardipine-TOF, control-PTC and control-TOF. In the nicardipine-PTC and nicardipine-TOF groups, nicardipine 0.03 mg kg-1 was given before vecuronium 0.1 mg kg-1 and a continuous infusion of nicardipine was started immediately at a rate of 2 micrograms kg-1 min-1. Mean time from administration of vecuronium to onset of neuromuscular block in the nicardipine-PTC and nicardipine-TOF groups was significantly shorter than in the control-PTC and control-TOF groups (166 (SD 39) vs 220 (28) s; P < 0.05). There was no significant difference in recovery of PTC between the nicardipine-PTC and control-PTC groups or in recovery of TOF ratio in the nicardipine-TOF and control-TOF groups. However, during recovery, T1/T0 in the nicardipine-TOF group was significantly less than that in the control-TOF group, 60-100 min after administration of vecuronium.

Evaluation of the applicability of sevoflurane during post-tetanic myogenic motor evoked potential monitoring in patients undergoing spinal surgery

“…The success rate for "all muscles" indicates the percentage of patients with MEP responses from all muscle recording sites is followed by a post-tetanic increase in twitch tension (i.e., post-tetanic fasciculation of transmission). The post-tetanic count after tetanic stimulation at 50 Hz for 5 s has therefore become an accepted technique to quantify the degree of intense neuromuscular bockade under the condition in which responses to single-twitch stimulation are no longer obtained [20][21][22]. Kakimoto et al [14] hypothesized that the application of tetanic stimulation to peripheral nerves prior to transcranial stimulation might augment the amplitudes of MEPs from the muscles that were innervated by the nerve subjected to the tetanic stimulation.…”

Drugs to facilitate recovery of neuromuscular blockade and muscle strength

“…It has been reported that PTC and the TOF ratio represent the degree of neuromuscular blockade at the prejunctional region of the neuromuscular junction, and the T1/control is related to the depth of neuromuscular blockade in the postjunctional region [1]. As noted above, nicorandil speeds not only recovery of the T1/ control but also that of the TOF ratio.…”

“…More than a decade ago many calcium channel blockers were reported to enhance the action of nondepolarizing neuromuscular relaxants [1][2][3]. Calcium channel blockers inhibit the release of acetylcholine at the neuromuscular junction and enhance the degree of neuromuscular blockade [1][2][3].…”

“…Calcium channel blockers inhibit the release of acetylcholine at the neuromuscular junction and enhance the degree of neuromuscular blockade [1][2][3]. In anesthetized patients receiving calcium channel blockers, the duration of neuromuscular blockade is prolonged.…”