The Divided Doses of Neostigmine for the Rapid Recovery at Profound Muscle Relaxation of Pancuronium in Rabbits / 대한마취과학회지

BACKGROUND: The reversal of neuromuscular blocker might be accelerated if the anticholinesterase was administered in divided doses. This study has been conducted to evaluate the correct ratio of divided doses of neostigmine for the rapid recovery in the rabbits after pancuronium when the profound relaxation(PTC=0) was confirmed. METHODS: Rabbits(n=60) were randomly allocated to 6 groups. After pancuronium 0.2 mg/kg intravenously, spontaneous recovery was evaluated in group 1. When the profound relaxation(PTC=O) was confirmed at 5 min. after pancuronium, neostigmine 50 ug/kg was injected as a bolus in group 2. At that time, neostigmine was given at 10 ug/kg followed by 40 ug/kg 3 min. later in group 3. At that time, neostigmine was given at 20 ug/kg followed by 30 ug/kg 3 min. later in group 4. At that time, neostigmine was given at 30 ug/kg followed by 20 ug/kg 3 min. later in group 5. At that time, neostigmine was given at 40 ug/kg followed by 10 ug/kg 3 min. later in group 6. RESULTS: The mean time from injection of pancuronium to 95% recovery was 99.3 min. in group 1, 59.8 min. in group 2, 53.2 min. in group 3, 51.5 min. in group 4, 50.8 min. in group 5 and 41.1 min. in group 6. The recovery index was significantly reduced in group 6(p<0.05). CONCLUSIONS: We conclude that the recovery time is reduced when neostigmine is administered in divided doses: a larger priming dose followed by a smaller bolus at profound relaxation.

The Priming Principle with Anticholinesterases for the Recovery of Profound Muscle Relaxation / 대한마취과학회지

The success of accelerating the onset of neuromvacular blocking drugs by giving them in divided doses encouraged others to attempt the same "priming principle" using reversal agents. Naguib et al and Abdulatif et al demonstrated that the reversal time(time to reach a TOF of 0.75) was reduced when the reversal agent was administered in divided doses at T, 10% of control. But Donati et al and Szalados et al either could not detect any differences in the rate of reversal when anticholinestereses were administered in divided doses. This study hes been conducted to evaluate the reversal effects of neostigmine or pyridostigmine with priming principle in the rabbit after pancuronium injection when pro- found relaxation(PTC=0) was confirmed. Rabbits(n=60) were randomly allocated to 4 groups. After pancuranium 0.2mg/kg IV, the onset and recovery times were evalusted. When the profound relaxation(PTC=0) was confirmed at Smin. after pancuronium injection, neostigmine 50 ug/kg and atropine sulfate (atropine) 20 ug/kg were injected in group 1. At thst time, neostigmine 10/kg and atropine 4 ug/kg were injected and after 3min. neostigmine 40/kg and atropine 16 ug/kg were injected in group 2. At that time, pyridostigmine 250 ug/kg and atropine 20 ug/kg were injected in group 3. At that time, pyridostigmine 50 ug/kg and atropine 4 ug/kg were injected and after 3min. pyridostigmine 200 ug/kg and atropine 16 ug/kg were injected in group 4. The results were as follows :. 1) The time until 75% recovery of twitch amplitude was 53.1+/-12.4min. in group 1, 44.9+/-212.1min. in group 2, 54.9+/-9.7min. in group 3 and 48.2+/-7.1min. in group 4. The reversal times were tended to reduce when the reversal agents were administered with "priming principle" at the profound relaxation. 2) At the profound relaxation the reversal effects of neostigmine were greater than that of pyridostigmine.