**Core Concept**
The patient is experiencing a life-threatening complication of thyroidectomy, specifically a hematoma formation in the neck. The swelling and difficulty breathing are due to external compression of the airway and potential circulatory compromise. This condition requires immediate recognition and management to prevent airway obstruction and potential cardiac arrest.

**Why the Correct Answer is Right**
The patient's symptoms suggest a rapidly expanding hematoma in the neck, which can compress the trachea and esophagus. The correct answer is the most appropriate management strategy for this emergency situation. The patient needs to be taken to the operating room for immediate surgical exploration and evacuation of the hematoma. This is often referred to as an emergency tracheostomy or a cricothyrotomy to secure the airway. The timely recognition and management of this complication can prevent serious morbidity and mortality.

**Why Each Wrong Option is Incorrect**
**Option A:** Administering oxygen and monitoring the patient's vital signs is not sufficient to address the life-threatening airway compromise. This option does not provide any immediate relief or resolution to the problem.
**Option B:** Performing a CT scan or other imaging studies would delay the necessary surgical intervention and may not provide timely information to guide management. In an emergency situation like this, imaging is not the priority.
**Option C:** Administering steroids and antihistamines may help to reduce swelling, but it is not a substitute for immediate surgical intervention to evacuate the hematoma and secure the airway.

**Clinical Pearl / High-Yield Fact**
In the immediate postoperative period following thyroidectomy, patients should be observed closely for signs of hematoma formation, such as swelling, difficulty breathing, or voice changes. If these symptoms occur, the patient should be taken to the operating room immediately for surgical exploration and evacuation of the hematoma.

**Correct Answer: C. Administering oxygen and monitoring the patient's vital signs is not sufficient to address the life-threatening airway compromise. Performing a CT scan or other imaging studies would delay the necessary surgical intervention and may not provide timely information to guide management. Administering steroids and antihistamines may help to reduce swelling, but it is not a substitute for immediate surgical intervention to evacuate the hematoma and secure the airway.