Which statement explains why a low serum potassium (hypokalemia) is of concern in preoperative planning?

Which statement explains why a low serum potassium (hypokalemia) is of concern in preoperative planning?

• A. Potassium protects against infection
• B. Low potassium increases risk for dysrhythmias
• C. Potassium has no effect on anesthesia
• D. Hyperkalemia would be more concerning

Answer: (B)

Potassium directly controls the heart’s electrical activity, so having a low level sets the stage for rhythm problems once anesthesia and surgery begin. When potassium is low, cardiac cells become more electrically unstable, which can slow conduction and promote abnormal rhythms. This makes patients more susceptible to arrhythmias during induction, airway manipulation, and surgical stress, especially as anesthetic drugs and shifts in fluids and electrolytes further challenge the heart. Correcting potassium toward normal before anesthesia helps stabilize the cardiac conduction system and reduces that risk, which is why this statement best explains why hypokalemia is a concern in preoperative planning. The other ideas aren’t the issue here: potassium does influence anesthesia through its effect on the heart, not infection protection, and while high potassium is dangerous in its own right, the question focuses on why low potassium matters in this setting.

Potassium directly controls the heart’s electrical activity, so having a low level sets the stage for rhythm problems once anesthesia and surgery begin. When potassium is low, cardiac cells become more electrically unstable, which can slow conduction and promote abnormal rhythms. This makes patients more susceptible to arrhythmias during induction, airway manipulation, and surgical stress, especially as anesthetic drugs and shifts in fluids and electrolytes further challenge the heart. Correcting potassium toward normal before anesthesia helps stabilize the cardiac conduction system and reduces that risk, which is why this statement best explains why hypokalemia is a concern in preoperative planning.

The other ideas aren’t the issue here: potassium does influence anesthesia through its effect on the heart, not infection protection, and while high potassium is dangerous in its own right, the question focuses on why low potassium matters in this setting.