Vecuronium Administration for Endotracheal Intubation: The Priming Method vs. Intravenous Infusion Method / 대한마취과학회지

BACKGROUND: Priming significantly shortened the onset of neuromuscular blockade(NMB), but also results in a high incidence of side effects. This study was designed to determine the effect of infusion priming method on the side effects, intubation condition, and onset of NMB compared with divided priming method. METHOD: The effects of different priming method of vecuronium on onset time and endotracheal intubation condition were investigated. 40 patients were studied in two parts. In control part, 20 patients were allocated into two groups(n=10 in each group) receving 10, 20 g/kg vecuronium as a priming dose, followed by a intubating dose(0.1 mg/kg-priming dose) 3 min later; the other part, 20 patients were allocated into two groups(n=10 in each group) receving 0.2 mg/kg/hr vecuronium continuous intravenous infusion, followed by a intubating dose(0.1 mg/kg-total infusion dose) 3, 5 min later. Onset time is calculated by single twitch stimulation test from injection of the intubating dose to maximum depression of the single twitch. Intubatin condition was appreciated based on vocal cord reflex, coughing, and jaw relaxation and scored. RESULTS: The times to fade out on the single twitch of the intravenous infusion priming group were shorter than control priming group. There was no difference between control priming group and infusion priming group to evaluate the intubation conditions. Side effects in the continuous infusion group were lesser than control priming group. CONCLUSION: This results suggest that the use of continuous infusion method is one of the promising methods to shorten the neuromuscular blockade and to provide more comfort to the patients.

Effects of Pseudocholinesterase, Anticholinesterase, and 4-Aminopyridine to the Mivacurium-induced Neuromuscular Block on Rat Diaphragm / 대한마취과학회지

BACKGROUND: Prolongation of the neuromuscular block of mivacurium can occur when there is a genetic deficiency of the enzyme or in the presence of anticholinesterase (AntiChE) which inhibit the activity of the enzyme. The aim of this study was to determine the efficacies of cholinesterase, AntiChE (neostigmine, pyridostigmine), and 4-aminopyridine in reversing mivacurium block, using the phrenic nerve-diaphragm preparation of a rat. METHODS: Forty-eight Sprague-Dawley rats (200~300 g) were anesthetized with peritoneal injection of 2.5% thiopental 5~10 ml. After a stable twitch and train-of-four responses were established for at least 30 minutes in each preparation, incremental dose of mivacurium was added to obtain 90~95% inhibition of control twitch height. The effects of 0.1 and 1.0 u/ml of horse pseudocholinesterase (pChE, Sigma), 0.1 and 1.0 g/ml of neostigmine, 0.2 and 2.0 g/ml of pyridostigmine, and 1.6, 16 g/ml of 4-aminopyridine (P.B.I) on reversal of mivacurium block were tested. The effects of 0.1 g/ml of neostigmine, or 0.2 g/ml of pyridostigmine with and without 0.1 or 1.0 u/ml of pChE following mivacurium were also tested. RESULTS: In reversing mivacurium block, single twitch and TOF ratios were recovered completely with pChE but not with antiChEs or 4-aminopyridine (p<0.05). Second set of experiments showed that antiChE mixed with pChE had a tendency to recover faster (p<0.05). The comparable recovery patterns of pChE 0.1u/ml alone and neostigmine 0.1 g/ml with pChE 0.1u/ml in our study, indicated that neostigmine would prolong the mivacurium block especially in the presence of hereditary or acquired defects of pChE activity. CONCLUSION: The authors conclude that pChE 1.0 u/ml with and without antiChE were equally effective in reversing neuromuscular block of mivacurium. If these results can be extrapolated to human, it is unlikely that mivacurium block is potentiated by antiChE that may slow its metabolism.

Comparison of Response between the Ulnar , Facial , Peroneal and Tibial Nerve after Administration of Vecuronium / 대한마취과학회지

Since as neuromuscular blocking agents are usually used during general anesthesia, monitoring of muscle relaxation is integra1 part of the management of patients and the ulnar nerve is allowed commonly to evaluate of neuromuscu1ar blockade. But our study was designed to monitor neuromuscular blockade-induced Vecuronium blocakade in 40 ASA 1-2 adult pateints in various nerves other than ulnar nerve with the single twitch(T1) and post-tetanic count(PTC) methods. All patients were premedicated with glycopyrrolate 0.2 mg and hydroxizine 1 mg/kg Ihour before induction, and were inducted with thiopental sodium 5 mg/kg and maintained with nitrous oxide(50%) and enflurane(1-2%). The patients were randomly divided to 4 groups, the ulnar nerve group was monitored at the adductor pollicis muscle, the facial nerve group was monitored at the orbicularis oculi muscle, the peroneal nerve group was monitored at the extensor digitorum brevis muscle, and the tibial nerve group was monitored at the flexor hallucis brevis muscle. After administration of vecuronium bromide 0.1 mg/kg, the onset time, duration of action and recovery time were compared between 4 group by INNERVATOR(Fisher & Paykel Co). The results obtained were as follow; 1) At the onset time, the facial nerve group was significant shorter than the ulnar nerve group, but the tibial and peroneal nerve group was significant prolonged. 2) The action duration from disappearance of single twitch to first appearance of PTC was significant prolonged in the peroneal nerve group than the ulnar nerve group but no significance was observed in the facial and tibial nerve gruop. 3) The recovery time from disappearance of single twitch to first appearance of single twitch was significant prolonged in the peroneal nerve group than the ulnar nerve group but no significance was observed in the facial and tibial nerve group.

Comparison of Response between the Ulnar , Facial , Peroneal and Tibial Nerve after Administration of Vecuronium / 대한마취과학회지

Since as neuromuscular blocking agents are usually used during general anesthesia, monitoring of muscle relaxation is integra1 part of the management of patients and the ulnar nerve is allowed commonly to evaluate of neuromuscu1ar blockade. But our study was designed to monitor neuromuscular blockade-induced Vecuronium blocakade in 40 ASA 1-2 adult pateints in various nerves other than ulnar nerve with the single twitch(T1) and post-tetanic count(PTC) methods. All patients were premedicated with glycopyrrolate 0.2 mg and hydroxizine 1 mg/kg Ihour before induction, and were inducted with thiopental sodium 5 mg/kg and maintained with nitrous oxide(50%) and enflurane(1-2%). The patients were randomly divided to 4 groups, the ulnar nerve group was monitored at the adductor pollicis muscle, the facial nerve group was monitored at the orbicularis oculi muscle, the peroneal nerve group was monitored at the extensor digitorum brevis muscle, and the tibial nerve group was monitored at the flexor hallucis brevis muscle. After administration of vecuronium bromide 0.1 mg/kg, the onset time, duration of action and recovery time were compared between 4 group by INNERVATOR(Fisher & Paykel Co). The results obtained were as follow; 1) At the onset time, the facial nerve group was significant shorter than the ulnar nerve group, but the tibial and peroneal nerve group was significant prolonged. 2) The action duration from disappearance of single twitch to first appearance of PTC was significant prolonged in the peroneal nerve group than the ulnar nerve group but no significance was observed in the facial and tibial nerve gruop. 3) The recovery time from disappearance of single twitch to first appearance of single twitch was significant prolonged in the peroneal nerve group than the ulnar nerve group but no significance was observed in the facial and tibial nerve group.