Which electrolyte disturbance can succinylcholine cause?

Which electrolyte disturbance can succinylcholine cause?

• A. Hypokalemia
• B. Hyponatremia
• C. Hyperkalemia
• D. Hypocalcemia

Answer: (C)

A depolarizing blocker like succinylcholine can trigger a rise in extracellular potassium from skeletal muscle during its initial depolarization. When succinylcholine activates nicotinic acetylcholine receptors, the motor endplate briefly depolarizes and then remains in a depolarized state, causing potassium to leak out of muscle cells through opened channels. In most people this increase is small, but in patients with upregulated extrajunctional acetylcholine receptors—such as after burns, severe trauma, denervation, prolonged immobilization, or certain neuromuscular diseases—the potassium efflux can be substantial and lead to dangerous hyperkalemia and potentially life-threatening arrhythmias. That’s why hyperkalemia is the electrolyte disturbance most associated with succinylcholine. It does not cause hypokalemia, hyponatremia, or hypocalcemia, which involve different mechanisms.

A depolarizing blocker like succinylcholine can trigger a rise in extracellular potassium from skeletal muscle during its initial depolarization. When succinylcholine activates nicotinic acetylcholine receptors, the motor endplate briefly depolarizes and then remains in a depolarized state, causing potassium to leak out of muscle cells through opened channels. In most people this increase is small, but in patients with upregulated extrajunctional acetylcholine receptors—such as after burns, severe trauma, denervation, prolonged immobilization, or certain neuromuscular diseases—the potassium efflux can be substantial and lead to dangerous hyperkalemia and potentially life-threatening arrhythmias. That’s why hyperkalemia is the electrolyte disturbance most associated with succinylcholine. It does not cause hypokalemia, hyponatremia, or hypocalcemia, which involve different mechanisms.