Certified Registered Nurse Anesthetist (CRNA) Practice Exam

How can succinylcholine impact serum potassium levels?

1. It can decrease potassium levels.

2. It can cause hyperkalemia.

3. It has no effect on potassium levels.

4. It can lead to hypokalemia.

The correct answer is: It can cause hyperkalemia.

Succinylcholine can lead to hyperkalemia due to its mechanism of action as a depolarizing neuromuscular blocker. When succinylcholine is administered, it binds to nicotinic acetylcholine receptors at the neuromuscular junction, causing muscle depolarization and subsequent fasciculation. This depolarization allows potassium to move from inside the muscle cells into the serum, leading to an increase in serum potassium levels. In patients with certain conditions, such as burns, denervation injuries, or other states of altered muscle membrane integrity, there may be an even more pronounced release of potassium, resulting in significant hyperkalemia that can be clinically relevant, especially in the context of anesthesia where cardiovascular stability is critical. Therefore, monitoring potassium levels is essential when using succinylcholine, particularly in at-risk populations.