A 34-year old woman is scheduled for a subtotal thyroidectomy. She has lost 10 pounds over the last nine months, and currently weighs 98 pounds. She is 62" tall. She was started on propylthiouracil five days ago and propranolol three days ago. She has smoked five packs of cigarettes per day for the past eighteen years, but recently decreased to one-half pack per day, due to asthmatic symptoms. She is visibly anxious and has a large firm thyroid. She has a chronic cough, is notably hoarse, and has mild expiratory wheezes. Blood pressure is 138/92 mmHg, pulse is 110, respirations are 18, and temperature is 37.6 degrees centigrade.
I. Thyroid status
1. How would you assess her current thyroid function?
2. What laboratory test would be helpful?
3. What is the significance of hyperthyroidism to anesthetic management?
4. Why is propranolol indicated?
5. Is the patient adequately prepared for thyroidectomy? Why or why not?
II. Evaluation of the airway
1. Is her hoarseness significant?
2. How would you evaluate her airway preoperatively?
3. Are pulmonary function tests helpful to specifically evaluate her airway?
4. Explain which tests would be helpful, and why.
1. Does this patient have special premedication requirements? Why or why not?
2. Which drugs would you use? Explain.
3. Would you continue propranolol? Why or why not?
4. Are steroids indicated? Why or why not?
I. Choice of anesthesia
1. Is regional anesthesia a consideration? Why or why not?
2. What regional technique would provide satisfactory anesthesia? Explain.
3. The patient insists on being asleep. Is awake intubation indicated? Why or why not?
4. Are there alternatives if her airway is questionable?
5. How would you induce anesthesia? Explain.
II. Maintenance of general anesthesia
1. Would you choose a nitrous oxide/narcotic technique for maintenance? Why or why not?
2. If not, give your choice and your reasons.
3. Does the patient's thyroid status influence your choice of agents?
4. Is muscle relaxant necessary? Why?
5. Would you particularly avoid any of the non-depolarizing agents?
III. Management of bronchospasm
1. Shortly after induction, the patient develops intense wheezing. What may be the cause?
2. How do you differentiate the etiology?
3. If the diagnosis appears to be bronchoconstriction secondary to reactive airway disease, how would you manage the patient? Explain.
IV. Management of dysrhthmia
1. During the resection of the thyroid, she develops tachycardia at 150 bpm. How do you assess the rhythm?
2. What might the rhythm be?
3. How could you confirm the diagnosis?
4. It is atrial flutter. What will you do?
5. Would your approach be different if she were hypotensive? Explain.
I. Management of extubation
1. Would you extubate this patient awake or deep? Explain why.
2. After extubation, stridor is noted. How would you proceed with evaluation?
3. What is your management?
II. Postoperative hypocalcemia
1. On your postoperative visit on postoperative day one, you find the patient irritable and confused, with irregular muscle twitching. What is your impression?
2. How will you proceed?
3. What is your differential diagnosis for hypocalcemia?
It is caused by parathyroid dysfunction or removal, and is seen with rapid transfusion of citrated blood products.