Surgery in the patient with endocrine dysfunction

Severe Hypothyroxinemia in a Young Adult with Carbimazole-Treated T3-Predominant Graves' Hyperthyroidism, Reversed with L-Thyroxine Loading Immediately Post-Total Thyroidectomy

Patients with triiodothyronine (T3)-predominant Graves’ hyperthyroidism with markedly elevated serum thyroid stimulating immunoglobulin (TSI) levels and massive goitre may display discordant hypothyroxinemia with eutriiodothyroninemia or hypertriiodothyroninemia while on anti-thyroid drug therapy. A 25-year-old female with the above was started on oral carbimazole therapy for 9 months before total thyroidectomy. Preoperatively, her serum free T4 was reduced to below detection limit, and total T4 reduced to 11% of lower limit of normal, while T3 levels remained normal, and TSH remained largely suppressed. Immediately after total-thyroidectomy, a loading dose of L-thyroxine (L-T4) was administered intravenously. She was extubated without any postoperative complications. Serum free and total T4, and TSH normalized within the next 24 hours. The peculiar thyroid axis dynamics and use of L-T4 postoperative loading in such a rare clinical scenario are discussed.

Postoperative myxedema coma in patients undergoing major surgery: Case series

OBJECTIVE

Myxedema coma is a serious complication of hypothyroidism that can be precipitated by major surgery. It is extremely rare, with only a few reports in the literature. This study aims to present a relatively large case series of post-surgical myxedema coma and to analyze medical and surgical risk factors.

METHODS

Analysis of the patients' surgical records and medical charts.

RESULTS

Four patients developed postoperative myxedema coma and were evaluated for risk factors. Three had known hypothyroidism. Two had undergone large head and neck composite resections necessitating a free flap repair for malignant disease. One had undergone coronary artery bypass graft for ischemic heart disease, and another had undergone endoscopic cholecystectomy for complicated cholecystitis. All four patients required prolonged hospitalization, including treatment in the intensive care unit. One patient had undergone full cardiopulmonary resuscitation directly related to the myxedema coma state.

CONCLUSION

We present a series of four patients who developed myxedema coma following major surgery. We recommend that patients with known hypothyroidism who are scheduled for major surgery should be tested for thyroid function status and assessed for postoperative risk of hypothyroidism. Those who develop complications following major surgery, should be immediately tested for thyroid function to rule out myxedema coma.

[Perioperative treatment for the urgent orbital decompression surgery in a 30-weeks pregnant woman with Graves' orbitopathy]

Thyroid ophthalmopathy is a rare extra-thyroid complication usually associated with Graves' disease. This disease can occur in the euthyroid pregnant patient. Graves' orbitopathy is characterized by eyelid retraction, proptosis, extraocular muscle dysfunction, and periorbital edema. In some cases an emergency surgical repair may be required to avoid irreversible vision loss. We present the case of a 35-year-old woman in her 30th gestational week, who suffered from Graves' ophthalmopathy, severe exophthalmia, and visual acuity decrease. Following consultations among anesthesiologists, ophthalmologists, maxillofacial surgeons, endocrinologists, obstetricians and the patient, it was decided to perform a surgical orbital wall decompression. The anesthetic and perioperative implications associated with gestational age and the considerations for this surgical procedure, and how to avoid increasing intraocular pressure are discussed.