Neuromuscular blocking agents

Background

• Non-depolarizing
  • Competitively block binding of ACh to its receptors
• Depolarizing
  • Depolarizing skeletal muscle fiber
  • Persistent depolarization makes the muscle fiber resistant to further stimulation by ACh

Types

Neuromuscular Blocking Agents

Agent	Time to onset (seconds)	Duration (minutes)	Side effects	Clinical use
Non-Depolarizing
Succinylcholine			fasciculations, post-operative pain
Depolarizing
Atracurium (Tracrium)	90	30 min or less	hypotension, transiently, by release of histamine Toxic metabolite called laudanosine, greater accumulation in individuals with renal failure
Vecuronium (Norcuron)	60	30–40	Few, may cause prolonged paralysis and promote muscarinic block
Rocuronium (Zemuron)	75	45–70	may promote muscarinic block
Pancuronium (Pavulon)	90	180 or more	tachycardia (slight) (no hypotension)