Pancuronium is a typical non-depolarising curare-mimetic muscle relaxant. It acts as a competitive acetylcholine antagonist on neuromuscular junctions, displacing acetylcholine (hence competitive) from its post-synaptic nicotinic acetylcholine receptors. It is, unlike suxamethonium, a non-depolarising agent, which means, that it causes no spontaneous depolarisations upon association with the nicotinic receptor in neuromuscular junction, thus producing no muscle fasciculations upon administration. Pancuronium has no hormonal activity. It exerts slight vagolytic activity (i.e. diminishing activity of the vagus nerve) and no ganglioplegic (i.e., blocking ganglions) activity.

Nondepolarizing neuromuscular blocking agents inhibit neuromuscular transmission by competing with acetylcholine for the cholinergic receptors of the motor end plate, thereby reducing the response of the end plate to acetylcholine. This type of neuromuscular block is usually antagonized by anticholinesterase agents.

Pancuronium is indicated as an adjunct to general anesthesia, to facilitate endotracheal intubation and to provide skeletal muscle relaxation during surgical procedure of medium and long duration.

Facilitate endotracheal intubation, Muscle relaxant in general anaesthesia:

• Adult: Initially, 50-100 mcg/kg by inj, may reduce to 20-60 mcg/kg if given after suxamethonium. Maintenance: 10-20 mcg/kg.
• Child: 0-30 days Initially, 30-40 mcg/kg. Maintenance: 10-20 mcg/kg; >1 mth Same as adult dose.

Facilitate mechanical ventilation in intensive care:

• Adult: 60 mcg/kg every 1-1.5 hr or less frequently.

Pancuronium must not be administered to patients with know hypersensitivity to puncuronium of the bromide ion.

Tachycardia, HTN, bradycardia, bronchospasm, hypotension, CV collapse, excessive salivation; pain or local skin reactions at inj site. Rarely, hypersensitivity reactions.

Overdose Effects

Symptoms: Prolonged apnoea, resp depression and/or muscle weakness. Death may follow acute resp failure.

Management: May administer neostigmine 2.5 mg and atropine 1.2 mg to reverse neuromuscular block while ventilation is continued. When admin of the anticholinesterase agent fails to reverse neuromuscular blockade, continue ventilation until spontaneous breathing is restored.