Question

julie was diagnosed with an aggressive tumor of the thyroid. surgery was performed to remove the thyroid. however, post - operatively, julies blood ca²+ levels began declining to life - threatening levels. this decline is most likely due to
multiple choice
damage to the anterior pituitary during surgery.
post - traumatic stress disorder.
accidental removal of the parathyroid glands during surgery.
improper laboratory handling of blood samples.
thyroid hormone replacement therapy after the surgery.

Explanation:

Parathyroid glands secrete parathyroid hormone (PTH), which increases blood \(Ca^{2+}\) levels. If accidentally removed during thyroid surgery, PTH secretion stops, leading to declining \(Ca^{2+}\) levels. The anterior pituitary (no role in \(Ca^{2+}\) regulation), post - traumatic stress disorder (psychological, not related to \(Ca^{2+}\) regulation), improper lab handling (unlikely as a single cause for life - threatening decline), and thyroid hormone replacement (for thyroid hormones, not \(Ca^{2+}\) regulation) are incorrect.

Answer:

accidental removal of the parathyroid glands during surgery.