Neuromuscular Blockade – Part 3
The second main class of drugs that physicians use to paralyze patients are the nondepolarizing neuromuscular blocking drugs. These drugs cause their effect by blocking the ion channels at the motor endplate. Transmission of nerve impulses is blocked when 80% to 90% of the receptors are blocked.
The nondepolarizing neuromuscular blocking drugs can be subclassified according to their structure and duration of action. The benzylisoquinolinium drugs are very potent (i.e., strong in effect) but are slower in onset. These drugs are eliminated by the kidneys or Hofmann elimination and may trigger histamine release. Examples of these drugs are atracurium, cisatracurium, mivacurium, and tubocurarine.
The aminosteroid nondepolarizing neuromuscular blocking drugs are less potent and have a faster onset of action. They are eliminated by the liver and do not cause significant histamine release.
Copyright 2006 Insidesurgery.com