McKenna's Pharmacology for Nursing, 2e

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Neuromuscular junction blocking agents

Learning objectives Upon completion of this chapter, you should be able to: 1. Draw and label a neuromuscular junction.

2. Describe the therapeutic actions, indications, pharmacokinetics, contraindications, most common adverse reactions and important drug–drug interactions associated with the depolarising and non-depolarising neuromuscular junction blockers. 3. Discuss the use of neuromuscular junction blockers across the lifespan. 4. Compare and contrast the prototype drugs pancuronium and suxamethonium with other neuromuscular junction blockers. 5. Outline the care considerations, including important teaching points, for people receiving a neuromuscular junction blocker.

Test your current knowledge of neuromuscular junction blocking agents with a PrepU Practice Quiz!

Glossary of key terms acetylcholine-receptor site: area on the muscle cell membrane where acetylcholine (ACh) reacts with a specific receptor site to cause stimulation of the muscle in response to nerve activity depolarising neuromuscular junction (NMJ) blocker: stimulation of a muscle cell, causing it to contract, with no allowance for repolarisation and re-stimulation of the muscle; characterised by contraction and then paralysis malignant hyperthermia: reaction to some NMJ drugs in susceptible individuals; characterised by extreme muscle rigidity, severe hyperpyrexia, acidosis and in some cases death neuromuscular junction (NMJ): the synapse between a nerve and a muscle cell non-depolarising neuromuscular junction (NMJ) blocker: no stimulation or depolarisation of the muscle cell; prevents depolarisation and stimulation by blocking the effects of acetylcholine paralysis: lack of muscle function sarcomere: functional unit of a muscle cell, composed of actin and myosin molecules arranged in layers to give the unit a striped or striated appearance sliding filament theory: theory explaining muscle contraction as a reaction of actin and myosin molecules when they are freed to react by the inactivation of troponin after calcium is allowed to enter the cell during depolarisation

NEUROMUSCULAR JUNCTION BLOCKING AGENTS Non-depolarising NMJs atracurium cisatracurium

Depolarising NMJ suxamethonium

mivacurium pancuronium rocuronium vecuronium