The nurse should identify which electrolyte imbalance as most likely in a patient with hyperemesis gravidarum?

The nurse should identify which electrolyte imbalance as most likely in a patient with hyperemesis gravidarum?

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

Answer: (D)

Vomiting and dehydration from hyperemesis gravidarum primarily cause loss of gastric potassium along with hydrogen and chloride, leading to a hypokalemic state. The reduced fluid volume triggers hormonal changes that promote renal potassium loss, and the metabolic alkalosis that results from loss of H+ and Cl− shifts potassium into cells, reducing its extracellular level. This combination makes low potassium the most characteristic electrolyte disturbance in this scenario. While low calcium or magnesium aren't typically driven by vomiting alone, and hyponatremia is less common unless there are additional fluid or intake issues, the classic finding here is hypokalemia with a concomitant metabolic alkalosis.