Post-tetanic count and intense neuromuscular blockade with vecuronium in children

S A Ridley1, N Braude

  • 1Hospital For Sick Children, London.

Insights

Vecuronium infusion provides adequate neuromuscular blockade for pediatric surgery, but its duration can be unpredictable, especially in infants under 5 kg. Monitoring with a peripheral nerve stimulator is recommended for safe anesthesia management.

Area of Science:

  • Anesthesiology
  • Pediatric Surgery
  • Pharmacology

Background:

  • Neuromuscular blockade is crucial for pediatric surgery.
  • Vecuronium is a commonly used non-depolarizing neuromuscular blocking agent.
  • Optimizing vecuronium infusion for pediatric patients requires careful dose titration and monitoring.

Purpose of the Study:

  • To evaluate the efficacy and safety of a continuous vecuronium infusion for maintaining neuromuscular blockade in children undergoing surgery.
  • To determine the optimal infusion rate and assess the predictability of neuromuscular blockade duration.
  • To compare the characteristics of vecuronium blockade with other agents like atracurium.

Main Methods:

  • Sixty pediatric surgical patients were divided into three weight-based groups.
  • All received an initial vecuronium loading dose (80 µg/kg) followed by a continuous infusion (initially 1.4 µg/kg/min).
  • Neuromuscular blockade was monitored using post-tetanic counts (PTC), aiming for a PTC of 5-15.

Main Results:

  • Adequate paralysis was achieved and easily reversed within 6-18 minutes after stopping the infusion.
  • The duration of the initial intense block was unpredictable, particularly in infants weighing less than 5 kg.
  • Vecuronium appeared to accumulate after 3 hours of infusion, suggesting a reduced presynaptic effect compared to atracurium.

Conclusions:

  • Continuous vecuronium infusion can provide effective neuromuscular blockade in pediatric surgery.
  • The unpredictability of the initial block duration highlights the importance of using a peripheral nerve stimulator for monitoring, especially in smaller infants.
  • Vecuronium accumulation may occur with prolonged infusions, impacting its presynaptic activity.

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