Surgical causes of hyper Ca2+:
**Core Concept**
Hypercalcemia is a condition characterized by elevated serum calcium levels, which can be caused by various factors including surgical interventions. This concept is crucial in understanding the pathophysiology of hypercalcemia and its management.
**Why the Correct Answer is Right**
The correct answer is related to the release of parathyroid hormone-related protein (PTHrP) due to tumor lysis syndrome or bone metastasis. When a tumor is resected during surgery, the rapid release of calcium from the tumor can lead to hypercalcemia. Additionally, the production of PTHrP by tumor cells can also stimulate the release of calcium from bones, leading to an increase in serum calcium levels.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it is not directly related to surgical causes of hypercalcemia. While vitamin D toxicity can cause hypercalcemia, it is not a common complication of surgery.
**Option B:** This option is incorrect because it is more related to metabolic causes of hypercalcemia, such as primary hyperparathyroidism. Surgical causes of hypercalcemia are typically related to the release of calcium from tumors or bone metastasis.
**Option C:** This option is incorrect because it is a common cause of hypocalcemia, not hypercalcemia. Hypocalcemia is a condition characterized by low serum calcium levels.
**Clinical Pearl / High-Yield Fact**
It is essential to remember that hypercalcemia can be a complication of surgical resection of tumors, especially those that produce PTHrP. Therefore, monitoring serum calcium levels post-operatively is crucial in these patients.
**Correct Answer:** D.