Page 32 Complete Your CE Test Online - Click Here The respirations of patients in myxedema coma are quite depressed, leading to an increase in the partial pressure of carbon dioxide in arterial blood. Cardiac output is decreased, and cerebral hypoxia occurs and progresses. Heart rate slows, and blood pressure drops. The patient becomes hypothermic and stuporous[6] . Myxedema coma alert! Myxedema coma is a medical emergency and requires life-saving actions. Patients are admitted to the intensive care unit. Most experts recommend the intravenous administration of thyroid hormones. Electrolyte and volume disturbances must also be corrected[5,6] . Clinical presentation and diagnosis The early clinical manifestations of hypothyroidism are vague and nonspecific. These include fatigue, lethargy, unexplained weight gain, menstrual changes, forgetfulness, reduced attention span, constipation, and sensitivity to cold, especially of the hands and feet[5,6] . As the disease progresses, signs and symptoms more characteristic of hypothyroidism become evident. These include[5,6,11] : ● ● Anorexia. ● ● Decreased libido. ● ● Drooping upper eyelids. ● ● Dry, flaky, thick skin. ● ● Hoarseness. ● ● Menorrhagia (painful menstruation). ● ● Muscle cramps. ● ● Paresthesia (numbness or tingling of extremities). ● ● Puffy face. ● ● Puffiness under the eyes. ● ● Stiff joints. ● ● Thick, brittle nails. ● ● Thinning, dry hair. Additional signs, symptoms, and complications related to specific body systems eventually develop[5,6,11] . ● ● Cardiovascular system: Elevated cholesterol, arteriosclerotic and ischemic heart disease, heart failure, cardiomegaly, poor peripheral circulation, and pericardial and pleural effusions. ● ● CNS: Ataxia, intention tremors, carpal tunnel syndrome, gradually progressing mental impairment, and psychiatric disturbances. ● ● GI system: Achlorhydria (absence of hydrochloric acid), pernicious anemia, adynamic (weak) colon, megacolon, and obstruction of the intestine. ● ● Hematologic system: Anemia, iron deficiency anemia, and bleeding tendencies. ● ● Reproductive system: Impaired fertility. ● ● Senses: Deafness and nystagmus (rapid, involuntary movement of the eyes). Severe hypothyroidism is referred to as myxedema. Its characteristic traits include thickened facial features, rough, hard, dough-like, cool skin, bradycardia, weak pulse, muscle weakness, delayed reflexes, and sacral and/or peripheral edema. Hyponatremia may also be present, and the thyroid tissue may not be readily palpable[5,11] . Untreated, myxedema may gradually progress to myxedema coma (see Complications)[5,11] . Nursing consideration: Because initial symptoms are vague it is important that nurses and other HCPs be alert to the possibility of hypothyroidism. In addition to clinical manifestations, several tests are used to confirm the diagnosis of hypothyroidism. In primary hypothyroidism (hypothyroidism is due to a disorder of the thyroid gland itself), TSH levels are elevated. In secondary hypothyroidism (hypothyroidism is due to failure to stimulate normal thyroid function as a result of hypothalamic or pituitary insufficiency), TSH levels are decreased[5,6] . Radioimmunoassay shows low T3 and T4 levels[5,6] . Serum cholesterol, alkaline, phosphatase, and triglyceride levels are elevated. Normocytic normochromic anemia may be evident [5] . Electrocardiogram (ECG) shows sinus bradycardia, low voltage of QRS complexes, and flat or inverted T waves[6] . Treatment and nursing considerations Treatment for mild cases of hypothyroidism involves gradual thyroid replacement with levothyroxine (Levoxyl, Synthroid), a synthetic form of the T4 thyroid hormone. This medication is a stable for of the thyroid hormone and is given orally once a day[5,14,15] . Occasionally, liothyronine is given for inadequate T3 levels[5] . Other thyroid hormone replacements are available, but as of this writing are not often recommended for replacement therapy. These medications include desiccated thyroid hormone, T3 (triiodothyronine), and various combinations of thyroid hormones T3 and T4[15] . For severe cases of hypothyroidism such as myxedema coma it is essential to provide more aggressive quick-acting treatment including [6] : ● ● Administration of T3 since it acts more quickly than T4. In unconscious patients it is administered via nasogastric tube. ● ● Administration of sodium levothyroxine (Synthroid) parenterally for the restoration of T4 levels. Parenteral administration continues until the patient regains consciousness. ● ● Administration of oral thyroid hormone after the patient regains consciousness and is able to swallow oral preparations. ● ● Initiate steroid therapy if the rapid administration of thyroid hormone triggers adrenal insufficiency. Nursing consideration: It is imperative to monitor vital signs carefully when levothyroxine is administered. Rapid correction of hypothyroidism can trigger cardiac problems. Elderly patients are at particular risk for hypertension and heart failure. Chest pain and/ or tachycardia should be reported immediately. Teach patients and families to report any signs of cardiovascular disease such as chest pain and rapid heart rate as well[5] . Nurses must be alert to signs and symptoms of hyperthyroidism after thyroid hormone replacement begins. There is always a danger of over- correction leading to abnormally high thyroid hormone levels. Teach patients and families about these signs and symptoms (restlessness, sweating, and unexplained excessive weight loss) and to report their occurrence to their HCPs immediately[5,6] . Treatment alert! Warn patients and families that thyroid hormone replacement therapy may increase the effects of digoxin and anticoagulants. Teach them to monitor the patient’s pulse and to monitor for signs of bleeding such as bleeding gums and blood in stools[6] . Encourage patients to wear medical alert bracelets at all times. Warn patients and families to take thyroid replacement therapy exactly as prescribed and to never discontinue taking their medication unless told to do so by the prescribing physicians. Emphasize that they must tell any physician or HCP (such as dentists or nurse practitioners) who prescribes medications for them about their hypothyroidism[5,6] . As always, teach patients and families not to take any additional medications or supplements without the approval of the physician who is supervising their hormone replacement therapy. This includes OTC medications, herbal preparations, vitamins, minerals, weight loss products, or any other supplements[5,6] . Treatment alert! Explain to patients and families that patients will need to take life-long hormone replacement therapy. Warn them that replacement therapy must not be discontinued even when they begin to feel better and signs and symptoms begin to subside and resolve[5,6] .