Parathyroidectomy is a technically challenging surgery with a relatively high rate of risk. One risk is for hypocalcemia, because removal of the parathyroid glands reduces secretion of parathyroid hormone (PTH). Since the glands are small, it is possible to remove all four instead of just three of four (or the one that remains is incapable of meeting demand). However, another risk is damage to the recurrent laryngeal nerve which runs through the area. This can lead to a hoarse voice and difficulty making sounds because of lack of control over the larynx. Stridor in the bronchi is not an issue because the surgery takes place at the level of the thyroid gland, near the trachea. Cold intolerance is a symptom of hypothyroidism, not hypoparathyroidism. Subclavian steal syndrome is caused by retrograde blood flow through the vertebral artery or internal thoracic because the subclavian artery is stenotic. This is unrelated to parathyroidectomy.