A nurse is reviewing the medical record of an adolescent and notes a calcium level of 11.4 mEq/L. Which of the following findings should the nurse expect?

Choice A rationale Tachycardia is not a typical finding for hypercalcemia. A calcium level of 11.4 mEq/L is above the normal range of 8.5 to 10.5 mg/dL or 4.5 to 5.5 mEq/L. High calcium levels actually have a sedative effect on the cardiovascular system, often leading to bradycardia or heart blocks. Excessive calcium shortens the QT interval and can lead to various arrhythmias, but the initial neuromuscular and cardiac depression usually results in a slower, rather than faster, heart rate. Choice B rationale Muscle hypotonicity is a direct result of elevated serum calcium levels. Hypercalcemia decreases neuromuscular excitability because the high concentration of calcium ions raises the threshold required for sodium channels to open and initiate an action potential. This leads to muscle weakness, diminished deep tendon reflexes, and general lethargy. The patient may feel uncoordinated or exhausted because the muscles and nerves are less responsive to stimuli, which is a hallmark clinical manifestation of this specific electrolyte imbalance. Choice C rationale Diarrhea is not expected with hypercalcemia; instead, constipation is a very common finding. High calcium levels decrease the motility of the smooth muscles in the gastrointestinal tract. This slowing of peristalsis leads to increased water absorption in the colon, resulting in hard stools and decreased frequency of bowel movements. Patients with a calcium level of 11.4 mEq/L are much more likely to report abdominal pain and a lack of bowel movements than frequent loose stools. Choice D rationale A positive Chvostek's sign is an indicator of hypocalcemia, or low calcium, not hypercalcemia. This sign involves a twitching of the facial muscles when the facial nerve is tapped, indicating neuromuscular irritability. In hypercalcemia, the nerves are less irritable, so this reflex would be absent. To see a positive Chvostek's sign, the calcium level would typically need to be below the normal range of 8.5 mg/dL, reflecting an increased sensitivity of the nervous system to stimulation.