What is a severe side effect of succinylcholine in genetically predisposed individuals?

Succinylcholine is a neuromuscular blocker commonly used in anesthesia, particularly for intubation due to its rapid onset and short duration of action. However, in genetically predisposed individuals, such as those with a deficiency in ryanodine receptors or certain genetic mutations related to calcium handling in muscle cells, a severe and dangerous reaction known as malignant hyperthermia can occur.

Malignant hyperthermia is a life-threatening condition characterized by a hypermetabolic state of skeletal muscle, leading to increased calcium release from the sarcoplasmic reticulum. This results in muscle rigidity, increased body temperature, and metabolic acidosis. The genetic predisposition often involves mutations in the ryanodine receptor (RYR1 gene), which plays a crucial role in muscle contraction and calcium regulation. When succinylcholine is administered, it triggers this abnormal release of calcium, leading to the hyperthermic crisis.

This severe reaction necessitates immediate medical intervention, as it can rapidly lead to complications such as cardiac dysrhythmias, renal failure, and potentially death if not managed promptly with dantrolene and supportive care. Understanding this risk highlights the importance of screening individuals for genetic susceptibility to malignant hyperthermia before administering succinylcholine