THYROID GLAND_AND THYROID DISORDERS

The Thyroid Gland Butterfly shaped organ Located in the lower neck, anterior to the trachea Is not normally palpable Blood flow to thyroid is very high. This reflects the high metabolic activity of the thyroid gland 4229100171450000 Thyroid Hormones The thyroid gland releases three hormones T4, T3, and Calcitonin Thyroxine (T4) and Triiodothyronine (T3) T4 and T3 are referred to collectively as thyroid hormone Both are amino acids that contain iodine molecules bound to the amino acid structure These hormones are synthesized and stored bound to proteins in the cells of the thyroid gland until needed for release into the blood stream Iodine is essential for the synthesis of the thyroids hormones 51435005372100The term euthyroid refers to thyroid hormone production that is within normal limits Regulation of Thyroid Hormone: The secretion of thyroid hormone is controlled by TSH (thyrotropin) from the anterior pituitary gland TSH controls the rate of thyroid hormone release through a negative feedback mechanism The level of thyroid hormone in the in blood determines the release of TSH Example: *If thyroid concentration in the blood decreases, the release of TSH increases Primary Function: Thyroid hormone controls cellular metabolic activity. Calcitonin Secreted in response to high plasma levels of calcium Reduces the plasma level of calcium by increasing its deposition in bone Function of the thyroid hormone Control cellular activity T4- weaker hormone (maintains metabolism) than T3 (more rapid metabolic action) Influence cell replication Important in brain development Necessary for “normal” growth Calcitonin: Secreted in response to high plasma Calcium levels Reuses plasma calcium (when necessary) and places into bone Pathophysiology Hypothyroidism inadequate secretion of thyroid hormone Cretinism: Stunned physical and mental growth from inadequate production during fetal and neonatal development Adults: Manifests as – Lethargy Slow mentation Generalized slowing of body functions Hyperthyroidism Oversecretion of thyroid hormones = increased metabolic rate Manifestations: Increased response to circulating catecholamines (epi & norepi) Associated with: Enlarged thyroid gland (goiter) or iodine deficiency Assessment and Diagnostic Findings Inspection: assess swelling & asymmetry, ask pt to swallow, look for movement (normally rises with swallow). Thyroid gland (whole) not normally palpable- only isthmus- if anything. Enlargement noted?- Asses for __________? Indicative of hyperthyroidism Thyroid Function Tests, Thyroid Hormones, Thyroid Scanning, Biopsy & US 46863007086600Nursing Implications: Must note if client has taken meds or agents that contain Iodine (contrast, antiarrythimics, vitamins, cough syrups, hormones, chemo, steroids, antibiotics, some diuretics Thyroid Diagnostic Tests TSH- best screening test for thyroid function Serum free T4 T3 and T4 T3 resin uptake test Thyroid Antibodies Radioactive iodine uptake Fine-Needle Aspiration Biopsy Thyroid Scan, radioscan, or scintiscan Serum Thyroglobulin Thyroid Disorders Cretinism- deficient hormone at birth- stunted physical & mental growth Hypothyroidism- decreased thyroid hormone (mild to myxedema) (most common cause- autoimmune thyroiditis)- (Hashimoto’s disease) Hyperthyroidism- excessive output of thyroid hormones (most common type-Graves Disease) Thyroiditis- inflammation of thyroid gland (acute (caused by infection), sub-acute (associated c viral resp. infection), chronic (Hashimotos’ Disease) Goiter- caused by Iodine deficiency (swelling in neck) Thyroid cancer- increased incidence in clients with childhood exposure to radiation of head, neck, chest. Lesions that are hard, single, & fixed on palpation indicative of malignancy Hypothyroidism- Defined by cause Primary- 95% have issue with thyroid itself Central- Issue with failure of the pituitary gland, the hypothalamus or both Pituitary- pituitary cause Cretinism- deficiency at birth Myxedema- extreme symptoms of severe hypothyroidism -228600-228600Hypothyroidism Causes: Autoimmune Thyroiditis; Hashimoto’s disease (most common cause) ***SEE CHART? Affects women 5X more than men Manifestations: Early Symptoms may be nonspecific Fatigue; hair, skin and nail changes; numbness and tingling of fingers; menstrual disturbances, subnormal temperature and pulse; weight gain; subdued emotional and mental responses; slow speech; tongue, hands, and feet may enlarge; personality and cognitive changes; cardiac –pericardial effusion & respiratory complications –pleural effusion See p 1257 00Hypothyroidism Causes: Autoimmune Thyroiditis; Hashimoto’s disease (most common cause) ***SEE CHART? Affects women 5X more than men Manifestations: Early Symptoms may be nonspecific Fatigue; hair, skin and nail changes; numbness and tingling of fingers; menstrual disturbances, subnormal temperature and pulse; weight gain; subdued emotional and mental responses; slow speech; tongue, hands, and feet may enlarge; personality and cognitive changes; cardiac –pericardial effusion & respiratory complications –pleural effusion See p 1257 3429000-114300 Myxedema (severe hypothyroidism) may progress to stupor, coma, and death- hypothermic & unconscious 14859005257800 Medical Management of Hypothyroidism Synthetic levothyroxine-replacement therapy- (Synthroid)- replaces missing hormone-Dosage based on TSH levels Medication interactions- see chart 42-2 p 1256 Effects of hypnotic and sedative agents; reduce dosage * See nursing alert p 1257 Support of cardiac function and respiratory function Hypothyroidism = elevated cholesterol, Atherosclerosis, & coronary artery disease Prevention of complications: Prevent Cardiac Dysfunction-As long as metabolism is subnormal and the tissue receive less than normal O2, they adapt, when the thyroid hormone is administered, it takes time for the O2 delivery to catch up with the oxygen demand Prevent Medication Interactions- watch for increased blood glucose levels, see med list, bone loss and osteoporosis Hypothyroidism Supportive Therapy With hypoventilation- assess for carbon dioxide retention (Watch O2 Saturation, confusion) Fluids cautiously- water intoxication risk Avoid external heat- heating pads = increases O2 consumption Plan of Care/Nursing Interventions: (p.1259-60) Activity Intolerance (fatigue/ depressed cognition) Imbalanced Body Temperature (cold intolerance) Constipation( depressed GI function) Knowledge Deficit-Medication replacement therapy Ineffective Breathing Pattern (depressed ventilation) Disturbed Thought Processes (depressed metabolism, cardio & pulmonary status) Myxedema & Myxedema Coma Hyperthyroidism Excessive output of thyroid hormone The second most prevalent endocrine disorder (after DM)- affects women more than men Caused By Graves disease (most common cause) Inflammation after radiation or hypothyroidism treatment *Tell Tale Manifestations of “thyrotoxicosis” (group of manifestations): see p.1262 nervousness; hyperexcitable, emotional, irritable, apprehensive, cant sit still, palpitations; rapid pulse; tolerate heat poorly; tremors; skin is flushed, warm, soft, and moist; however, elders’ skin may be dry and pruritic (itching); exophthalmos (bulging eyes), increased appetite and dietary intake; weight loss; elevated systolic BP; may progress to cardiac dysrhythmias and failure Exophalamous (bulging eyes)- not always reversible (even with treatment)Smoking can make changes worse Increased Appetite AND intake AND weight loss Abnormal muscular fragility (weakness) Amenorrhea Bowel Changes Pulse 90-160 Elevated SYSTOLIC BP Cardiac: Sinus tachycardia, myocardial Hypertrophy, CHF Osteoporosis & fractures 1371600514350000 Assess & Assess & Assess Greatly increased Blood Flow: Enlarged Gland ( Inspection & Palpation) Thyroid may pulsate Bruit auscultated over arteries Labs: Decrease in serum TSH, increase free T4, increase in radioactive Iodine Uptake Medical Management of Hyperthyroidism Irradiation: (Radioactive 131I therapy) – destroys the overactive thyroid cells Medications (Anti-thyroid meds) interrupt synthesis of hormones (See p. 1264 Table 42 3) Propylthiouracil and methimazole, Sodium or potassium iodine solutions, Dexamethasone (steroid), Beta-blockers Surgery; subtotal thyroidectomy Relapse of disorder is common Disease or treatment may result in hypothyroidism Nursing Interventions: Plan of Care Imbalanced Nutrition- less than requirements Ineffective Coping- irritability Low Self esteem- physical changes, excessive appetite, weight loss Most physical changes will disappear with medical management Diet: Avoid- caffeine, coffee, tea, ETOH, stimulants, & highly seasoned foods High calorie- High protein Quiet Cool Atmosphere Thyroid Storm: (Thyrotoxic Crisis, Thyrotoxicosis) Etiology: stress, infection, thyroid surgery, abrupt withdrawal of antithyroid meds Life threatening Cardiac dysrythimias Tachycardia (greater than 130 bpm) Fever Neurological impairment Exaggerated symptoms of Hyperthyroidism GI- weight loss, diarrhea, abdominal pain; Cardiovascular: chest pain, dyspnea, palpatations Treatment: Hypothermia blanket, hydrocortisone, cool enviornment, Inderal- Beta Blocker, PTU- antithyroid med, Iodine (must observe for goiter development), Lanoxin Thyroidectomy Treatment of choice for thyroid cancer Cancer surgery may include modified or radical neck dissection, and may include treatment with radioactive iodine to minimize metastasis Preoperative goals include the reduction of stress and anxiety to avoid precipitation of thyroid storm Preoperative teaching includes: dietary guidance to meet patient metabolic needs and avoidance of caffeinated beverages and other stimulants, explanation of tests and procedures, and demonstration of support of head to be used postoperatively Post-operative Care Monitor dressing for potential bleeding and hematoma formation; check posterior dressing Monitor respirations; potential airway impairment Tracheostomy Set at bedside at all times Assess pain and provide pain relief measures Semi-Fowler’s position, support head Assess voice but discourage talking (checking laryngeal nerve function) Potential Complications: Hypocalcaemia related to injury or removal of parathyroid glands; monitor for hypocalcemia s/s Hypocalcemia: spasms of hands and feet, muscle twitching, hyperirritability of the nerves- treatment- IV Calcium Gluconate The nurse is caring for a patient diagnosed with Hashimoto's thyroiditis. When assessing this patient, what symptom would the nurse expect in a patient with hypothyroidism? A) Numbness and tingling in the fingers B) Bulging eyes C) Palpitations D) Flushed skin Feedback: Symptoms of hypothyroidism include extreme fatigue, hair loss, brittle nails, dry skin, voice huskiness or hoarseness, menstrual disturbance, and numbness and tingling of the fingers. Bulging eyes, palpitations, and flushed skin would be signs and symptoms of hyperthyroidism. A nurse works in a walk-in clinic. The nurse recognizes that certain patients are at higher risk for different disorders than other patients. What patient is at a greater risk for the development of hypothyroidism? A) A 75-year-old female B) A 50-year-old male C) A 45-year-old female D) A 25-year-old male Feedback: Hypothyroidism affects women five times more frequently than men, and occurs most often between 30 and 60 years of age. The 45-year-old female has a greater risk for the development of hypothyroidism. Therefore options A, B, and D are incorrect. A 77-year-old patient with hypothyroidism is undergoing right knee replacement surgery. The nurse caring for this patient knows that all patients with hypothyroidism have a prolonged reaction to what type of medication? A) Antibiotics B) Antihypertensive agents C) Anticholenergic agents D) Anesthetic agents Feedback: In all patients with hypothyroidism, the effects of analgesic agents, sedatives, and anesthetic agents are prolonged; special caution is necessary in administering these agents to elderly patients because of concurrent changes in liver and renal function. This makes options A, B, and C incorrect. The nursing instructor is talking with the nursing students about hyperthyroidism. The instructor breaks students into small groups and assigns them the task of creating meal plans for patients with hyperthyroidism. What would the instructor expect the student's meal plans to include? A) A clear liquid diet B) Small, frequent meals, high in protein and calories C) Three large, bland meals a day D) A diet high in fiber and fat Feedback: A patient with hyperthyroidism has an increased appetite. The patient should be counseled to consume several well-balanced meals of small size. High-calorie, high-protein foods are encouraged. A clear liquid diet would not satisfy the patient's caloric or hunger needs. A diet rich in fiber and fat should be avoided as these foods may lead to gastrointestinal upset or increase peristalsis. The nurse is caring for a patient with hyperthyroidism. What would the nurse closely monitor for? A) Thyroid storm B) Hypoxia C) Cardiac output D) Hypoglycemia Feedback: The nurse closely monitors the patient with hyperthyroidism for signs and symptoms that may be indicative of thyroid storm. The nurse monitors for all of these things, but he or she monitors closely for thyroid storm. The PACU staff has brought a patient to the unit following a thyroidectomy. To promote comfort for this patient how would you position the patient? A) Side-lying (lateral) with one pillow under the head B) Head of the bed elevated 30 degrees and no pillows placed under the head C) Semi-Fowler's with the head supported on two pillows D) Flat, with a small roll supporting the neck Feedback: When moving and turning the patient, the nurse carefully supports the patient's head and avoids tension on the sutures. The most comfortable position is the semi-Fowler's position, with the head elevated and supported by pillows. Therefore options A, B, and D are incorrect. You are teaching a patient about nutrition. You know that the body needs iodine for the thyroid to function. What food would be the best source of iodine for the body? A) Eggs B) Strawberries C) Table salt D) Red meat Feedback: The major use of iodine in the body is by the thyroid. Iodized table salt is a source of iodine. Options A, B, and D are incorrect. A patient has returned to the floor after having a thyroidectomy for thyroid cancer. The nurse knows that sometimes during thyroid surgery the parathyroid glands can be injured or removed. What laboratory finding may be an early indication of parathyroid gland injury or removal? A) Hyponatremia B) Hypophosphatemia C) Hypocalcemia D) Hypokalemia Feedback: Injury or removal of the parathyroid glands may produce a disturbance in calcium