What is a major complication observed after a subtotal thyroidectomy within 12 to 48 hours?

A major complication observed after a subtotal thyroidectomy within 12 to 48 hours is thyroid storm. This condition, also known as thyroid crisis, is a severe and life-threatening hyperthyroid state that can occur after surgical manipulation of the thyroid gland. The stress of surgery can lead to a surge in thyroid hormones and trigger a hypermetabolic state in susceptible individuals. Symptoms of thyroid storm include fever, tachycardia, hypertension, agitation, and gastrointestinal disturbances.

While respiratory failure, myxedema coma, and acute renal failure are also concerning complications that can arise in various contexts, they are less directly related to the immediate aftermath of a subtotal thyroidectomy. Respiratory failure could occur due to various factors, including anesthesia or airway issues but is not specifically tied to thyroid hormone fluctuations. Myxedema coma is a severe form of hypothyroidism that occurs in chronic cases rather than acute post-surgical situations. Acute renal failure may arise from multiple underlying conditions but is not a specific complication linked to thyroid surgery. Thus, thyroid storm stands out as the critical complication to be vigilant about shortly after the procedure.