Hexafluronium bromide is a neuromuscular blocking agent used in anesthesiology to prolong and potentiate the skeletal muscle relaxing action of suxamethonium during surgery. It is known to bind and block the activity of plasma cholinesterases.
Indication
Used as an adjunct with succinylcholine (or suxamethonium chloride) to prolong muscle relaxation and to prevent succinylcholine-induced muscle fasciculations.
Pharmacology
Hexafluronium bromide is a cholinesterase antagonist that can be used to prolong the relaxation effects of succinylcholine or suxamethonium chloride. Suxamethonium acts as a depolarizing muscle relaxant. It imitates the action of acetylcholine at the neuromuscular junction and is degraded by pseudocholinesterase, a plasma cholinesterase. The prolonged stimulation of the acetylcholine receptor results first in disorganized muscle contractions, then in profound relaxation. Cholinesterases catalyze the hydrolysis of the neurotransmitter acetylcholine into choline and acetic acid, a reaction necessary to allow a cholinergic neuron to return to its resting state after activation. There are two types of cholinesterase acetylcholinesterase and pseuodocholinesterase. The first hydrolyses acetylcholine more quickly; the latter hydrolyses butyrylcholine and succinylcholine more quickly. An absence or mutation of the pseudocholinesterase enzyme leads to a medical condition known simply as pseudocholinesterase deficiency. This is a silent condition that only manifests itself when people who have the deficiency receive the muscle relaxants succinylcholine or mivacurium during a surgery.
