Question

The nurse knows to assess serum calcium levels for the patient with hyperparathyroidism because of which mechanism?

1) Increased osteoblastic activity in the bone
2) Decreased osteoclastic activity in the bone
3) Increased reabsorption of calcium by the kidneys
4) Increased reabsorption of phosphate by the kidneys

Answer 1

In hyperparathyroidism, PTH increases serum calcium by stimulating osteoclast activity and enhancing reabsorption of calcium in the kidneys, leading to higher serum calcium levels known as hypercalcemia.

Step-by-step explanation:

The nurse should assess serum calcium levels in a patient with hyperparathyroidism because of the effect of the parathyroid hormone (PTH) on calcium metabolism. Specifically, PTH causes:

1. Increased release of calcium into the bloodstream due to stimulation of osteoclast activity in the bones.
2. Increased reabsorption of calcium by the kidneys.

Therefore, option 3, 'Increased reabsorption of calcium by the kidneys', is the correct mechanism for why a nurse would monitor serum calcium levels in a patient with hyperparathyroidism. The increased action of osteoclasts mobilizes calcium from the bones, and PTH reduces the excretion of calcium by the kidney, causing an increase in serum calcium levels, known as hypercalcemia.