Thyroid Disorders Block 2 NUR 171

Disorders of Thyroid Gland The thyroid hormones T3 and T4 regulate energy metabolism growth and development. Disorders of the thyroid include goiter, benign and malignant nodules, inflammation, hyper-thyroid and hypothyroidism. Fig. 50-5. Continuum of thyroid dysfunction.

Hyperthyroidism Nursing and Collaborative Care A sustained increase in synthesis and release of thyroid hormones by thyroid gland Occurs more often in women Highest frequency in 20- to 40-year-olds Hyperthyroid: Affects multiple body systems, resulting in an overall increase in metabolism: S/S are: Diarrhea, Flushing, Increased appetite, Muscle weakness, Sleep disorders, Altered menstrual flow, Fatigue, Palpitations, Nervousness, Heat intolerance, Irritability Goals Block adverse effects of thyroid hormone Stop hormone over-secretion Thyroid preparations are given to replace what the thyroid gland cannot produce to achieve normal thyroid levels (euthyroid) Thyroid drugs work the same way as endogenous thyroid hormones

Hyperthyroidism Collaborative Care Radioactive iodine therapy Anti-thyroid drugs Iodine Β‑adrenergic blockers Surgical therapy Nutritional therapy Anti-thyroid drugs lower the T3 and T4 levels Iodine in large doses rapidly inhibit synthesis of T3and T4 and block their release into circulation, decreases vascularity of the thyroid gland- not for long term therapy Beta Blockers Propranolol and Atenolol, block the effects of the stress hormones catecholamines, block the effects of the sympathetic nervous system Copyright © 2011, 2007 by Mosby, Inc., an affiliate of Elsevier Inc.

Collaborative Care Radioactive iodine therapy (RAI) Treatment of choice in non- pregnant adults Damages or destroys thyroid tissue Delayed response 2 to 3 months Treated with anti-thyroid drugs and Inderal before and during first 3 months of AI RAI therapy is administered on an outpatient basis. Because the therapeutic dose of radioactive iodine is low, no radiation safety precautions are necessary. High incidence of post treatment hypothyroidism Need for lifelong thyroid hormone replacement Treatment of choice is radioactive iodine therapy. However, the choice of treatment is influenced by the patient’s age and preferences, severity of the disorder, and complicating features (including pregnancy).

Collaborative Care PTU: propylthiouracil, methimazole PTU treatment of hyperthyroid disorders OR toxic multinodular goiter. It inhibits the synthesis of thyroid hormones Adverse effects: drowsiness, headache, vertigo, GI: HEPATOTOXICITY, nausea, vomiting diarrhea decreased taste, Derm: skin rash, uticaria, discoloration, Endo: hypothyroidism, Heme: AGRANULOCYTOSIS, leukopenia, thrombocytopenia, MS: arthralgia, smoky urine, decreased urine output Nursing interventions: Assess: s/s hyper/hypothyroid [what are the symptoms of each? Make sure you know]VS, weight, heart rate rhythm, BP, check pregnancy Assess: rash, lymphadenopathy, blood dyscrasias [agranulocytosis may develop rapidly usually occurring with in the first 2 months. Assess/monitor: liver function tests [ast,alt,ldh, serum bilirubin and prothrombin Assess: weight 2-3x per week, may cause drowsiness so avoid driving. Assess/monitor:for s/s hyper/hypo thyroid. Pt should carry ID card, report chest pain, never stop abruptly Treat: administer at the same time each day. Food may either increase or decease absorption. Teach: Antithyroid medications are better tolerated when taken with meals or a snack. These drugs must also be given at the same time every day to maintain consistent blood levels of the drug. They must never be withdrawn abruptly. Take meds around the clock. RAI: destroys the thyroid gland: refer to lecture notes on this topic as it is more for lecture. Dietary sources of iodine> REPORT SORE THROAT, FEVER CHILLS HEADACHE MALAISE YELLOWING OF EYES OR SKIN, UNUSUAL BLEEDING, BRUSING. • Instruct patients taking thyroid or antithyroid drugs not to take any over-the-counter medications without first consulting with the prescriber or pharmacist and to read all drug labels thoroughly. • Patients taking antithyroid medications must avoid eating foods high in iodine, such as tofu and other soy products, turnips, seafood, iodized salt, and some breads. These foods may interfere with the effectiveness of the antithyroid drug

Collaborative Care Subtotal thyroidectomy Indications Unresponsive to drug therapy Large goiters causing tracheal compression Possible malignancy Individual not a good candidate for RAI One advantage thyroidectomy has over RAI is a more rapid reduction in T3 and T4 levels. Preferred surgical procedure Involves removal of significant portion of thyroid 90% removed to be effective If too much tissue is taken, the gland will not regenerate after surgery and hypothyroidism will result.

Hypothyroid Types & Symptoms One of the most common medical disorders in the United States Affects 1 in 50 women and 1 in 300 men Primary: abnormality in the thyroid gland itself Secondary: results when the pituitary gland is dysfunctional and does not secrete TSH Tertiary: results when the hypothalamus gland does not secrete thyrotropin-releasing hormone, which stimulates the release of TSH Common symptoms: Thickened skin, hair loss, Constipation, Lethargy, Anorexia

Myxedema: Complication of Hypothyrodism Systemic effects characterized by slowing of body processes 2 types: young people: Cretinism Hypo- secretion of thyroid hormone during youth Low metabolic rate, retarded growth and sexual development, possible mental retardation Myxedema Hypo-secretion of thyroid hormone; Decreased metabolic rate, loss of mental and physical stamina, weight gain, loss of hair, firm edema, yellow dullness of the skin, Coma can be precipitated by infection, drugs (especially opioids, tranquilizers, and barbiturates), exposure to cold, and trauma. It is characterized by subnormal temperature, hypotension, and hypoventilation- prominent tongue, thick facial skin For the patient to survive, vital functions must be supported and IV thyroid hormone replacement must be administered.

Collaborative Care Levothyroxine (Synthroid) Liothyronine (Cytomel) Synthetic thyroid hormone T4 Liothyronine (Cytomel) Synthetic thyroid hormone T3 Must take regularly Monitor for angina and cardiac dysrhythmias. Monitor thyroid hormone levels, and adjust as needed Liotrix (Thyrolar) Thyroid preparations are given to replace what the thyroid gland cannot produce to achieve normal thyroid levels (euthyroid) Thyroid drugs work the same way as endogenous thyroid hormones Indications To treat hypothyroidism Levothyroxine is the preferred drug because its hormonal content is standardized; therefore, its effect is predictable Goals is to produce a “Euthyroid” state Also used for thyroid replacement in patients whose thyroid glands have been surgically removed or destroyed by radioactive iodine in the treatment of thyroid cancer or hyperthyroidism Adverse effects: Cardiac dysrhythmia is the most significant adverse effect Assess for: Tachycardia, palpitations, angina, hypertension, insomnia, tremors, headache, anxiety, nausea, diarrhea, menstrual irregularities, weight loss, sweating, heat intolerance, fever, others Treat: Give ½ to 1 hour before breakfast on an empty stomach to enhance their absorption orally, maintain constant hormone levels, and help prevent insomnia. Teach: Best taken ½ to 1 hour before breakfast on an empty stomach to enhance their absorption orally, maintain constant hormone levels, and help prevent insomnia. • Do not abruptly discontinue. Lifelong therapy is usually the norm. • Keep follow-up visits so the prescriber can monitor thyroid hormone levels, complete blood counts, and results of liver function studies. • Brands of thyroid replacement drugs cannot be interchanged. Advise patients to always check that the pharmacy has provided the correct brand of thyroid replacement drug. • Signs and symptoms associated with hypothyroidism include myxedema with decreased metabolic rate, loss of mental/physical stamina, weight gain, hair loss, firm edema, and yellow dullness of the skin. Share this information with the patient. • Instruct the patient taking thyroid replacement drugs to immediately report any of the following to the prescriber: chest pain, weight loss, palpitations, tremors, sweating, nervousness, shortness of breath, or insomnia. These may indicate toxicity. • Encourage the patient to keep a daily journal, with notations about how the patient is feeling, energy levels, appetite, and any adverse effects. • Advise the patient that it may take up to 3 to 4 weeks to see the full therapeutic effects of thyroid drugs. • All thyroid tablets must be protected from light. • Signs and symptoms of hyperthyroidism include increased metabolic rate, diarrhea, flushing, increased appetite, muscle weakness, fatigue, palpitations, irritability, nervousness, sleep disorders, heat intolerance, and altered menstrual flow. Patients with this disorder and on drug therapy need to be aware of these signs and symptoms. •. Any chest pain experienced by a patient starting thyroid replacement should be reported immediately, and an electrocardiogram (ECG) and serum cardiac enzyme tests must be performed. In the patient without side effects, the dose is increased at 4- to 6-week intervals. It is important that the patient take replacement medication regularly. Liotrix is a synthetic mix of levothyroxine (T4) and liothyronine (T3) in a 4:1 combination. Liotrix has a faster onset of action with a peak of 2 to 3 days, as opposed to levothyroxine, with a peak of 1 to 3 weeks.

The patient is experiencing hyperthyroidism. A patient has been taking levothyroxine for 6 months. After this month’s laboratory work, the nurse practitioner tells the nurse that the patient is “euthyroid.” What does that term mean? The patient is experiencing hyperthyroidism. The patient is experiencing hypothyroidism. The patient’s thyroid hormone levels are within normal limits. The patient’s thyroid hormone levels are still fluctuating. Correct answer: C Rationale: The term euthyroid means that normal thyroid hormone levels have been achieved. Elsevier items and derived items © 2009, 2005, 2001 by Saunders, an imprint of Elsevier Inc.

inadequate doses of the medication. A patient who is taking a thyroid replacement medication tells the nurse that she is starting to experience cold intolerance, depression, constipation, and dry skin. The nurse anticipates that these manifestations are caused by inadequate doses of the medication. possible overdose of the medication. worsening of the underlying disease. drug interactions with another medication. Correct answer: A Rationale: A return of the symptoms of hypothyroidism indicates that the patient is receiving inadequate doses of the medication. Elsevier items and derived items © 2009, 2005, 2001 by Saunders, an imprint of Elsevier Inc.

“Take the medication before bed.” Which information will the nurse include when teaching a patient about thyroid replacement therapy? “Take the medication before bed.” “You will experience beneficial effects of the drug after one week of treatment.” “Stop taking the drug if you experience insomnia.” “Take the medication on an empty stomach.” Correct answer: D Rationale: Thyroid replacement drugs are best taken ½ to 1 hour before breakfast on an empty stomach to enhance their absorption orally, maintain constant hormone levels, and help prevent insomnia. These medications should never be abruptly discontinued, and lifelong therapy is usually the norm. Patients should be advised that it may take up to 3 to 4 weeks to see the full therapeutic effects of thyroid drugs Elsevier items and derived items © 2009, 2005, 2001 by Saunders, an imprint of Elsevier Inc.

Pasta with marinara sauce Which would be the best menu choice for a patient who is taking an antithyroid medication? A seafood platter Sushi Tofu burger Pasta with marinara sauce Correct answer: A Rationale: The patient should avoid foods high in iodine, such as soy, tofu, and seafood. Elsevier items and derived items © 2009, 2005, 2001 by Saunders, an imprint of Elsevier Inc.