Which condition causes flaccid paralysis by partially depolarizing the muscle cell membrane?

Hyperkalemia, or elevated levels of potassium in the blood, can lead to flaccid paralysis through its effects on muscle cell excitability. When potassium levels are high, the resting membrane potential of muscle cells becomes less negative (a partial depolarization). This change in polarization decreases the muscle's ability to respond adequately to stimuli, leading to weakness and paralysis. The muscle fibers cannot generate the necessary action potentials to contract effectively, resulting in the characteristic flaccid paralysis.

Understanding the impact of hyperkalemia on muscle function is crucial, especially in critical care, where rapid identification and management of electrolyte imbalances are essential. Conditions like hypokalemia, hypercalcemia, and hyponatremia may have different effects on muscle function and do not cause flaccid paralysis through the same mechanism as hyperkalemia.