What are appropriate
preoperative tests for a patient with thyroid disease?
Patients with thyroid disease should have
recent evalua-tion of TSH and free T4 levels. These should be nearly
normal for elective surgery. Patients who have been on long-term
thyroid-hormone replacement do not need recent hormone levels, unless there has
been a change in symptoms.
Hypothyroidism can cause anemia and
thrombo-cytopenia, as well as hyponatremia, hypoglycemia, and cholestasis.
Thus, hypothyroid patients should have a complete blood count, platelet count,
electrolytes, glucose, and liver function tests evaluated preoperatively.
An electrocardiogram should be done looking for
the presence of atrial fibrillation, premature complexes, ischemia, or
ventricular hypertrophy. Other cardiac testing should be considered for
patients with cardiac symptoms.
All patients with a goiter or abnormal airway
physical examination should have radiological evaluation of the trachea, either
by radiography, CT, or MRI. Patients with large or retrosternal goiters should
have a CT scan or MRI. These studies will help guide the choice of anesthesia
(regional or general), intubation technique, and endo-tracheal tube size.