Zaib Hussain, Shan Elahi.
Undetected hypothyroidism and its anesthetic implications.
Anesth Pain Intens Care Jan ;16(2):205-10.

Hypothyroidism is a common disorder affecting the cardiovascular, respiratory, hematopoietic, and renal organ systems. Each of these systems is particularly relevant in the management of the surgical patient. Most reported complications have occurred in patients with unrecognized hypothyroidism. In general, treatment of recognized hypothyroidism is recommended before any surgical procedure whenever possible and normal levels of thyroid hormone should be documented as part of the preoperative evaluation. Such a strategy is likely to result in better surgical outcomes with improved morbidity and mortality.

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