CHAPTER 6 Endocrine Disorders

Section One Disorders of the Thyroid Gland

Hyperthyroidism

Overview/Pathophysiology

Hyperthyroidism is a clinical syndrome caused by excessive circulating thyroid hormone. Because thyroid activity affects all body systems, excessive thyroid hormone exaggerates normal body functions and produces a hypermetabolic state.

Lymphocytic (“painless”) thyroiditis and postpartum thyroiditis are autoimmune disorders that result in thyroid inflammation with release of stored thyroid hormone into systemic circulation. Postpartum thyroiditis may ensue several months after delivery and remain active for several months, sometimes followed by hypothyroidism lasting several months.

Subacute (granulomatous) thyroiditis is a viral syndrome resulting in a painful, enlarged, overactive thyroid until the infection is controlled. Hyperthyroid symptoms also result from ingestion of too much thyroid replacement medication.

Graves’ disease (diffuse toxic goiter) accounts for approximately 85% of reported cases of hyperthyroidism. It is characterized by spontaneous exacerbations and remissions that appear to be unaffected by therapy. The cause of Graves’ disease is unknown, but an immunoglobulin known as long-acting thyroid stimulator has been isolated in a majority of patients with this disorder, a finding suggesting that Graves’ disease is an autoimmune response.

Thyrotoxic crisis, or thyroid storm, is the most severe form of hyperthyroidism. It results from a sudden surge of large amounts of thyroid hormones into the bloodstream that cause an even greater increase in body metabolism. This is a medical emergency. Precipitating factors include infection, trauma, and emotional stress, all of which increase demands on body metabolism. Thyrotoxic crisis also can occur following thyroidectomy because of manipulation of the gland during surgery.

Assessment

Diagnostic Tests

Serum thyroid-stimulating hormone (TSH), or thyrotropin

Most commonly used test to detect thyroid dysfunction. It is decreased in the presence of disease.

Serum thyroxine (T₄) or free T₄

Elevated in the presence of disease. It may be more accurate than TSH if patients have been recently treated for hyperthyroidism or if they are receiving high doses of thyroid replacement therapy. T₄ should be monitored along with TSH for the first year of therapy, especially in older adults.

Serum triiodothyronine (T₃) radioimmunoassay (RIA) or free T₃

Elevated in the presence of disease.

Serum thyroid autoantibody assay

Detects TSH receptor antibodies (TRAb) and thyroid-stimulating immunoglobulins (TSIs), which may be present in autoimmune disease.

Doppler ultrasonography

Determines size of the gland and abnormal densities, which can indicate presence of nodules.

Radioactive iodine (¹³¹I) uptake and thyroid scan

Clarifies gland size and detects presence of hot or cold nodules.

Radioactive iodine (¹²³I) scintiscan/thyroid scintigraphy

Defines functional characteristics of the gland to help determine cause of hyperthyroidism.

Collaborative Management

Pharmacotherapy

Antithyroid agents

Propylthiouracil (PTU) and methimazole are the first line therapeutic agents. In milder cases, methimazole is preferred because it is taken once daily, a regimen that increases adherence to therapy. The most severe side effect of these drugs is leukopenia. Patients should discontinue the drug at the first sign of infection and be referred for a complete blood count (CBC). If the blood count is normal, medication is promptly resumed. Rash, another side effect, can be treated easily with antihistamines. For pregnant women, PTU is the drug of choice, because newborn infants have experienced scalp irritation when their mothers took methimazole while pregnant.

Radioactive iodine ablation

Approach used most commonly in the United States to resolve hyperthyroidism permanently. The thyroid is destroyed with radioactive iodine. The process takes 6-18 wk for completion. Severely symptomatic people, those with heart disease, and older adults should receive antithyroid drugs before receiving radioiodine in order to resolve symptoms more quickly. Radioiodine ablation is used for (1) failure to respond to antithyroid drugs, (2) relapse after 1-2 yr of therapy, (3) toxic multinodular goiter, (4) solitary toxic nodules, and (5) noncompliant patients. ¹³¹I is the most commonly used agent. Its use usually results in hypothyroidism, which is controlled easily with thyroid hormone replacement therapy. The small amount of radiation present in liquid or capsules does not cause cancer. About 10% of patients treated require a second dose.

β-Adrenergic blocking agents (e.g., atenolol or propranolol)

Relieve overactive thyroid symptoms, including tachycardia, anxiety, heat intolerance, and tremor. Once symptoms resolve with other medications or treatments, β-blocking agents may be discontinued.

Mild tranquilizers

Minimize anxiety and promote rest.

Diet

If significant weight loss has occurred, a diet high in calories, protein, carbohydrates, and vitamins is recommended to restore a normal nutritional state.

Thyroidectomy

Surgical removal of the gland may be necessary for patients with extremely enlarged glands that may partially obstruct the trachea or multinodular goiter. Surgery is done infrequently in the United States because most patients receive medical therapy with antithyroid medications or radioactive iodine. The patient is prepared with antithyroid agents until normal thyroid function is achieved (usually 6-8 wk). The most common postoperative complication is hemorrhage at the operative site. Rare but extremely serious complications are hypoparathyroidism, laryngeal nerve injury, and tetany, owing to damage to the parathyroid glands.

Nursing Diagnoses and Interventions

Imbalanced nutrition: less than body requirements

related to hypermetabolic state and/or inadequate nutrient absorption

Desired outcomes

At least 24 hr before hospital discharge, patient has adequate nutrition as evidenced by stable weight and a positive nitrogen balance. Within 24 hr of the instruction, patient lists types of foods that are necessary to restore a normal nutritional state.

Disturbed sleep pattern

related to accelerated metabolism

Desired outcome

Within 48 hr of hospital admission, patient relates attainment of sufficient rest and sleep.

Ineffective protection

related to risk for thyrotoxic crisis (thyroid storm) secondary to emotional stress, trauma, infection, or surgical manipulation of the gland

Desired outcomes

Patient is free of symptoms of thyroid storm as evidenced by normothermia; BP 90/60 mm Hg or more (or within patient’s baseline range); HR 100 beats per minute (bpm) or less; and orientation to person, place, and time. If thyroid storm occurs, it is noted promptly and reported immediately.

Nursing Interventions

♦ Measure and report rectal or core temperature greater than 38.3° C (101° F) because this often is the first sign of impending thyroid storm.

♦ Monitor VS hourly for evidence of hypotension and increasing tachycardia and fever in patients in whom thyroid storm is suspected, to facilitate early detection and treatment.

♦ Monitor patient for signs of heart failure, which occurs as an effect of thyroid storm: jugular vein distention, crackles (rales), decreased amplitude of peripheral pulses, peripheral edema, and hypotension. Immediately report any significant findings to health care provider, and prepare to transfer patient to the ICU if such findings are noted, to facilitate early treatment.

♦ Provide a cool, calm, protected environment to minimize emotional stress. Reassure patient and explain all procedures before performing them. Limit the number of visitors. Helps reduce metabolic rate.

♦ Ensure good handwashing and meticulous aseptic technique for dressing changes and invasive procedures. Advise visitors who have contracted or been exposed to a communicable disease to either not enter patient’s room or wear a surgical mask, if appropriate. Reduces the risk for infection, which will further increase metabolic rate.

♦ Implement emergency treatment if signs of thyroid storm are present:

• Administer acetaminophen as prescribed to decrease temperature. Aspirin is contraindicated because it releases T₄ from protein-binding sites and increases free T₄ levels.

• Provide cool sponge baths, or apply ice packs to patient’s axilla and groin areas. If high temperature continues, obtain prescription for a hypothermia blanket to decrease fever.

• Administer PTU as prescribed to prevent further synthesis and release of thyroid hormones.

• Administer propranolol as prescribed to block sympathetic nervous system (SNS) effects.

• Administer IV fluids as prescribed to provide adequate hydration and prevent vascular collapse.

• Monitor for fluid volume deficit, which may occur because of increased fluid excretion by the kidneys or excessive diaphoresis.

• Carefully monitor I&O hourly. Decreasing output with normal specific gravity may indicate decreased cardiac output, whereas decreasing output with increased specific gravity can signal dehydration. Detects fluid overload or inadequate fluid replacement.

• Administer sodium iodide as prescribed, 1 hr after administering PTU. If given before PTU, sodium iodide can exacerbate symptoms in susceptible persons.

• Administer small doses of insulin as prescribed. Hyperglycemia can occur as an effect of thyroid storm because of the hypermetabolic state. Insulin controls hyperglycemia.

• Administer supplemental O₂ as necessary because O₂ demands are increased as metabolism increases.

Anxiety

related to SNS stimulation

Desired outcomes

Within 24 hr of hospital admission, patient is free of harmful anxiety as evidenced by HR 100 bpm or less, respiratory rate (RR) 12-20 breaths/min with normal depth and pattern (eupnea), and absence of or decrease in irritability and restlessness. Patient and significant others verbalize knowledge about the causes of the patient’s behavior.

Nursing Interventions

♦ Assess for signs of anxiety; administer short-acting sedatives (e.g., alprazolam or lorazepam) as prescribed, to help control nervousness and restlessness from SNS stimulation.

♦ Provide a quiet, stress-free environment away from loud noises or excessive activity, to facilitate rest.

♦ Limit number of visitors and the amount of time they spend with patient. Advise significant others to avoid discussing stressful topics and refrain from arguing with the patient, to facilitate rest and decrease anxiety.

♦ Administer propranolol as prescribed, to reduce symptoms of anxiety, tachycardia, and heat intolerance.

♦ Reassure patient that anxiety symptoms are related to the disease process and that treatment decreases their severity, to reduce fear and facilitate coping.

♦ Inform significant others that patient’s behavior is physiologic and should not be taken personally, to reduce their anxiety and fears.

Impaired tissue integrity of the cornea

related to dryness that can occur with exophthalmos in persons with Graves’ disease

Desired outcome

Within 24 hr of admission, patient’s corneas are moist and intact.

Disturbed body image

related to exophthalmos or surgical scar

Desired outcome

Within the 24-hr period before hospital discharge, patient verbalizes measures for disguising exophthalmos or surgical scar and exhibits self-acceptance.

Deficient knowledge

related to risk for side effects from iodides and thioamides or stopping thioamides abruptly

Desired outcome

Within the 24-hr period before hospital discharge, patient verbalizes knowledge about potential side effects of prescribed medications, signs and symptoms of hypothyroidism and hyperthyroidism, and importance of following the prescribed medical regimen.

Nursing Interventions

♦ Assess patient’s facility with language; engage an interpreter or provide language-appropriate written materials if necessary.

♦ Explain importance of taking antithyroid medications daily, in divided doses, and at regular intervals as prescribed, to prevent hypermetabolism and resulting symptoms.

♦ Teach indicators of hypothyroidism, which may occur from excessive medication, and signs and symptoms that necessitate medical attention, including cold intolerance, fatigue, lethargy, and peripheral or periorbital edema, to facilitate early intervention of corrective treatment.

♦ Teach side effects of thioamides and symptoms that necessitate medical attention, including appearance of a rash, fever, or pharyngitis, which can occur in the presence of agranulocytosis.

♦ Alert patients taking iodides to signs of worsening hyperthyroidism, including high body temperature, palpitations, rapid HR, irritability, anxiety, and feelings of restlessness or panic, to facilitate early intervention if needed.

Acute pain

related to surgical procedure

Desired outcomes

Within 2 hr of surgery, patient’s subjective perception of pain decreases, as documented by a pain scale. Objective indicators, such as hesitation before turning or moving the head, are absent or diminished.

Impaired swallowing

(or risk for same) related to edema or laryngeal nerve damage resulting from surgical procedure

Desired outcomes

Patient reports swallowing with minimal difficulty, has minimal or absent hoarseness, and is free of symptoms of respiratory dysfunction, as evidenced by RR 12-20 breaths/min with normal depth and pattern (eupnea) and absence of inspiratory stridor. Laryngeal nerve damage, if it occurs, is detected promptly and reported immediately.

Nursing Interventions

♦ Monitor respiratory status for signs of edema (dyspnea, choking, inspiratory stridor, inability to swallow) and voice for hoarseness. Slight hoarseness is normal after surgery; hoarseness that persists is indicative of laryngeal nerve damage and should be reported to health care provider promptly. If bilateral nerve damage is present, upper airway obstruction can occur.

♦ Elevate head of bed (HOB) 30-45 degrees. Support patient’s head with flat or cervical pillows so that it is in a neutral position with the neck (does not flex or hyperextend) to minimize edema and incisional stress.

♦ Keep tracheostomy set and O₂ equipment at the bedside at all times. Suction upper airway as needed, and use gentle suction to avoid stimulating laryngospasm. Maintains patent airway.

♦ Administer analgesics promptly and as prescribed to minimize pain and anxiety and enhance patient’s ability to swallow.

Patient-Family Teaching and Discharge Planning

Include verbal and written information about the following:

♦ Diet high in calories, protein, carbohydrates, and vitamins. Inform patient that as a normal metabolic state is attained, the diet may change.

♦ Medications, including drug names, purpose, dosage, schedule, precautions, and potential side effects. Also discuss drug/drug, food/drug, and herb/drug interactions.

♦ Changes that can occur as a result of therapy, including weight gain, normal bowel function, increased strength of skeletal muscles, and return to normal activity levels.

♦ Importance of continued and frequent medical follow-up; confirm date and time of next appointment.

♦ Indicators that necessitate medical attention, including fever, rash, or sore throat (side effects of thioamides) and symptoms of hypothyroidism (see p. 383) or worsening hyperthyroidism.

♦ For patients receiving radioactive iodine, importance of not holding children to the chest for 72 hr following therapy because children are more susceptible to the effects of radiation. There is negligible risk for adults.

♦ Importance of avoiding physical and emotional stress early in the recuperative stage and maximizing coping mechanisms for dealing with stress.

Hypothyroidism

Overview/Pathophysiology

Hypothyroidism occurs from an inadequate amount of circulating thyroid hormone that causes a decrease in metabolic rate that affects all body systems.

Primary hypothyroidism accounts for 90% of cases of hypothyroidism and is caused by pathologic changes in the thyroid itself. The most common cause of the disease in the United States is chronic autoimmune thyroiditis (Hashimoto’s disease.) Secondary hypothyroidism is caused by dysfunction of the anterior pituitary gland, which results in decreased release of thyroid-stimulating hormone (TSH). Tertiary hypothyroidism is caused by a hypothalamic deficiency in the release of thyrotropin-releasing hormone (TRH).

Myxedema, a life-threatening condition, can occur when hypothyroidism is untreated or when a stressor such as infection affects an individual with hypothyroidism. The clinical picture of myxedema coma is that of exaggerated hypothyroidism, with dangerous hypoventilation, hypothermia, hypotension, shock, and possible coma and seizures. Myxedema coma usually develops slowly and has a greater than 50% mortality rate. It requires prompt and aggressive treatment.

Assessment

Signs and symptoms/physical findings

Early fatigue, weight gain from fluid retention, anorexia, lethargy, cold intolerance, hoarseness, ataxia, memory and mental impairment, decreased concentration, menstrual irregularities or heavy menses, infertility, constipation, depression, muscle cramps, possible presence of goiter, bradycardia, hypothermia, deepened voice, hyperlipidemia, and obesity. Skin may appear yellow and dry, cool, and coarse and hair may be thin, coarse, and brittle. The tongue may be enlarged (macroglossia), and reflexes may be slowed.

Myxedema coma

Hypoventilation, hypoglycemia, hypothermia, hypotension, bradycardia, and shock. Symptoms can progress from mild early in onset to life-threatening.

Treatment of Myxedema Coma

Intubation and mechanical ventilation

Compensate for decreased ventilatory drive.

IV thyroid supplements

Rapid IV administration of thyroid hormone can precipitate hyperadrenalism. This can be avoided by concomitant administration of IV hydrocortisone.

Treatment of hypotension

Administration of IV isotonic fluids, such as normal saline and lactated Ringer’s solution. Hypotonic solutions, such as 5% dextrose in water (D₅W), are contraindicated because they can decrease serum Na⁺ levels further. Because of altered metabolism, these patients respond poorly to vasopressors.

Treatment of hypoglycemia

IV glucose.

Treatment of hyponatremia

Fluids are restricted, or hypertonic (3%) saline is administered, or both.

Treatment of associated illnesses such as infections.

Because of alterations in metabolism, patients with hypothyroidism do not tolerate barbiturates and sedatives well, and therefore central nervous system (CNS) depressants are generally contraindicated.

Nursing Diagnoses and Interventions

Ineffective breathing pattern

(or risk for same) related to upper airway obstruction occurring with enlarged thyroid gland and/or decreased ventilatory drive caused by greatly decreased metabolism

Desired outcome

Patient has an effective breathing pattern as evidenced by respiratory rate (RR) 12-20 breaths/min with normal depth and pattern (eupnea), normal skin color, O₂ saturation (SaO₂) 95% or more, and absence of adventitious breath sounds. Alternatively, if ineffective breathing pattern occurs, it is detected, reported, and treated promptly.

Nursing Interventions

♦ Assess rate, depth, and quality of breath sounds, and be alert to presence of adventitious sounds (e.g., from developing pleural effusion) or decreasing or crowing sounds (e.g., from swollen tongue or glottis).

♦ Monitor for signs of inadequate ventilation, including changes in RR or pattern and circumoral or peripheral cyanosis. Immediately report significant findings to health care provider. May indicate early myxedema.

♦ Measure SaO₂ intermittently or continuously in patients with decreased ventilatory drive to verify adequacy of oxygenation.

♦ Teach patient coughing, deep breathing, and use of incentive spirometer. Suction upper airway prn to facilitate patent airway.

♦ For patient experiencing respiratory distress, be prepared to assist health care provider with intubation or tracheostomy and maintenance of mechanical ventilatory assistance or transfer patient to ICU.

Activity intolerance

related to weakness and fatigue secondary to slowed metabolism and decreased cardiac output caused by pericardial effusions, atherosclerosis, and decreased adrenergic stimulation

Desired outcome

During activity patient rates perceived exertion at 3 or less on a 0-10 scale and exhibits cardiac tolerance to activity as evidenced by heart rate (HR) 20 beats per minute (bpm) or less over resting HR, SBP 20 mm Hg or less over or under resting SBP, warm and dry skin, and absence of crackles (rales), murmurs, chest pain, and new dysrhythmias.

Risk for infection

related to compromised immunologic status secondary to alterations in adrenal function

Desired outcome

Patient is free of infection as evidenced by normothermia, absence of adventitious breath sounds, normal urinary pattern and characteristics, and well-healing wounds.

Nursing Interventions

♦ Assess for early indicators of infection, including fever, erythema, swelling, or discharge from wounds or IV sites; urinary frequency, urgency, or dysuria; cloudy or malodorous urine; presence of adventitious sounds on auscultation of lung fields; and changes in color, consistency, and amount of sputum. Notify health care provider of significant findings to facilitate early intervention if needed.

♦ Provide meticulous care of indwelling catheters to minimize risk of urinary tract infection (UTI).

♦ Use sterile technique when performing dressing changes and invasive procedures to minimize risk for infection.

♦ Provide good skin care to maintain skin integrity and prevent pressure ulcers.

♦ Advise visitors who have contracted or been exposed to a communicable disease not to enter patient’s room or to wear a surgical mask, if appropriate.

Risk for imbalanced nutrition: more than body requirements

related to slowed metabolism

Desired outcomes

Patient does not experience weight gain. Within the 24-hr period before hospital discharge, patient verbalizes understanding of rationale and measures for dietary regimen.

Constipation

related to inadequate dietary intake of roughage and fluids, prolonged bed rest, and/or decreased peristalsis secondary to slowed metabolism

Desired outcome

Within 48-72 hr of admission, patient relates attainment of his or her normal pattern of bowel elimination.

Nursing Interventions

♦ Assess current bowel function; document changes.

♦ Monitor for decreasing bowel sounds, presence of distention, and increases in abdominal girth. These may indicate ileus or obstructive process.

♦ Encourage patient to maintain a diet with adequate roughage and fluids. Examples of foods high in bulk include fruits with skins, fruit juices, cooked fruits, vegetables, whole grain breads and cereals, and nuts. Ensure that fluid intake in persons without underlying cardiac or renal disease is at least 2-3 L/day to prevent constipation.

♦ Administer stool softeners and laxatives as prescribed to facilitate bowel movement.

♦ Avoid suppositories and teach patient not to use suppositories, to stimulate bowel function. Suppositories are contraindicated because of risk of stimulating the vagus nerve, which would further decrease HR and BP.

♦ Advise patient to increase amount of exercise to promote bowel regularity.

Ineffective protection (risk of myxedema coma)

related to inadequate response to treatment of hypothyroidism or stressors such as infection

Desired outcomes

Patient is free of symptoms of myxedema coma, as evidenced by HR 60 bpm or greater, BP 90/60 mm Hg or greater (or within patient’s normal range), RR 12 breaths/min or more with normal depth and pattern (eupnea), and orientation to person, place, and time. Alternately, if myxedema coma occurs, it is detected, reported, and treated promptly.

Nursing Interventions

♦ Monitor VS at frequent intervals and be alert for bradycardia, hypotension, or decrease in RR. Report SBP less than 90 mm Hg, HR less than 60 bpm, or RR less than 12 breaths/min.

♦ Monitor patient for signs of hypoxia (circumoral or peripheral cyanosis, decrease in level of consciousness [LOC]). Immediately report significant findings to health care providers.

♦ Avoid external warming measures for patients with hypothyroidism who are hypothermic because they can produce vasodilation and vascular collapse.

♦ Carefully check medication doses and classifications carefully before administration, especially barbiturates and sedatives, which are generally contraindicated because they may cause excessive sedation, increased ventilatory effort, or decreased LOC.

♦ Monitor serum electrolytes and glucose levels. Be especially alert to decreasing Na⁺ (less than 137 mEq/L) and glucose (less than 80 mg/dL) because they may indicate myxedema.

Patient-Family Teaching and Discharge Planning

Include verbal and written information about the following:

♦ Medications, including drug names, purpose, dosage, schedule, precautions, and potential side effects. Also discuss drug/drug, food/drug, and herb/drug interactions. Remind patient that thioamides, iodides, and lithium are contraindicated because they decrease thyroid activity. Be sure patient is aware that thyroid replacement medications are to be taken for life.

♦ Dietary requirements and restrictions, which may change as hormone replacement therapy takes effect.

♦ Expected changes that can occur with hormone replacement therapy: increased energy level, weight loss, and decreased peripheral edema. Neuromuscular problems should resolve as well.

♦ Importance of continued, frequent medical follow-up; confirm date and time of next medical appointment.

♦ Importance of avoiding physical and emotional stress and ways for patient to maximize coping mechanisms for dealing with stress.

♦ Signs and symptoms that necessitate medical attention, including fever or other symptoms of upper respiratory, urinary, or oral infections and signs and symptoms of hyperthyroidism, which may result from excessive hormone replacement.

♦ Inform patient of available resources:

The American Thyroid Association: www.thyroid.org

The Thyroid Foundation of America: www.tsh.org

The Hormone Foundation: www.hormone.org

Section Two Disorders of the Parathyroid Glands

The parathyroid glands regulate serum calcium (Ca⁺⁺) and phosphorus levels via release of parathyroid hormone (PTH). This is accomplished by a negative-feedback mechanism: when serum Ca⁺⁺ levels rise, PTH secretion is suppressed. PTH acts on bone to decrease Ca⁺⁺ binding, and it stimulates the kidneys to increase resorption of Ca⁺⁺. Parathyroid glands affect serum phosphorus levels in two ways: (1) directly, in that PTH causes increased renal excretion of phosphorus; and (2) indirectly, in that phosphorus and Ca⁺⁺ combine readily to form an insoluble salt, and increased serum phosphorus facilitates this reaction, thus effectively lowering circulating Ca⁺⁺ levels. PTH is also involved in the synthesis of a renal enzyme that catalyzes formation of vitamin D, which, in conjunction with PTH, increases absorption of Ca⁺⁺ from the gastrointestinal (GI) tract.

Hyperparathyroidism

Overview/Pathophysiology

Hyperparathyroidism is a clinical syndrome occurring from excessive secretion of parathyroid hormone (PTH). Primary hyperparathyroidism is caused by pathology of one or more of the parathyroid glands. Approximately 80% of these cases are caused by a benign adenoma of one gland, another 10% by multigland involvement, and in rare cases by carcinoma. In this disorder, excessive PTH acts on the skeletal, renal, and gastrointestinal (GI) systems, and the overall effects are increased serum calcium (Ca⁺⁺) levels and decreased phosphate levels.

Hyperparathyroidism is the second most common cause of hypercalcemia. Incidence of this diagnosis increases dramatically after age 50 yr and is much more prevalent in female patients than in male patients. Secondary hyperparathyroidism is usually caused by renal insufficiency with decreased glomerular filtration. Although Ca⁺⁺ and phosphorus are retained because of the lack of renal filtration, the high serum phosphate level depresses Ca⁺⁺ concentration because phosphorus combines with Ca⁺⁺ to form insoluble salts, with resulting hypocalcemia. This hypocalcemia, in turn, stimulates the parathyroid glands to release PTH in an effort to increase serum Ca⁺⁺ levels. Bone resorption occurs because of increased PTH, but absorption of calcium from the GI tract is depressed because of Ca⁺⁺ binding with high-phosphate GI secretions. The overall effects are decreased Ca⁺⁺ levels and increased phosphate levels. Tertiary hyperparathyroidism occurs when secondary hyperparathyroidism progresses to a state in which excessive PTH is released independent of serum Ca⁺⁺ levels.

Diagnostic Tests

Serum Ca⁺⁺

Elevated in primary hyperparathyroidism and low in secondary hyperparathyroidism. This test usually is repeated at least three times to confirm diagnosis. Venous blood is drawn in the morning after patient has been fasting. Because Ca⁺⁺ is bound to protein, test results must be “corrected,” based on a simultaneous test for albumin level. Serum Ca⁺⁺ changes by 0.8 mg/dL for each 1 g/dL change in albumin level above or below normal. This represents circulating Ca⁺⁺ available for use by body cells and is considered the “true” Ca⁺⁺ level. To avoid venous stasis, which can produce erroneously high results, care must be taken not to apply the tourniquet too tightly or occlude the vessel for longer than necessary.

Serum PTH

High or inappropriately high for serum Ca⁺⁺ levels.

Plasma phosphorus

Decreased in primary hyperparathyroidism and elevated in secondary hyperparathyroidism.

24-hr urine Ca⁺⁺

Elevated in primary hyperparathyroidism. This test is often used to rule out other causes of hypercalcemia.

Bone dual-energy x-ray absorptiometry (DEXA) (bone density scan)

Will show diminution of bone mass in virtually all patients with hyperparathyroidism, as well as calcification of articular cartilage. X-ray examination of the hands will show subperiosteal resorption of the phalanges.

ECG

May show shortened QT interval, which is reflective of hypercalcemia.

Ultrasound scanning of the parathyroid glands

Used for operative planning when adenoma is suspected.

Radioisotope scan (sestamibi scan)

Patient receives radioactive material that is absorbed only by the diseased gland in order to locate the adenoma preoperatively.

Collaborative Management

For patients without symptoms

Some health care providers may recommend that patient watch and wait to see whether symptoms develop. If patient remains asymptomatic, no further treatment may be necessary.

Surgical Treatment of Hyperparathyroidism

Conventional parathyroidectomy for primary hyperparathyroidism

The most effective form of treatment for patients with symptomatic primary hyperparathyroidism is surgical removal of one or more of the parathyroid glands (parathyroidectomy). The traditional incision is somewhat wider than with thyroidectomy, but the surgery is very similar. Only the affected gland or glands are removed, and, in cases in which all the parathyroid glands are enlarged, glands are removed. The remaining tissue is enough to provide normal Ca⁺⁺ regulation. In addition to postoperative complications potentially found with thyroidectomy, abnormalities in serum Ca⁺⁺ levels also may be found.

Minimally invasive radioguided parathyroidectomy

A simple 1-inch incision is made, and in many cases the procedure can be done using local anesthesia. The surgeon uses the sestamibi scan as a guide and may use a special probe (similar to a Geiger counter) to locate the tumor for removal. Patients receiving local anesthesia may be able to return home the same day.

Medical Treatment for Hyperparathyroidism

Promotion of Ca⁺⁺ excretion

In the absence of heart failure or renal insufficiency, this is accomplished by forcing fluids orally or giving IV normal saline for patients who are stuporous or nauseated. Volumes up to 1000 mL/hr may be given for short periods.

Increase in salt intake by food or tablet

Because Na⁺ competes with Ca⁺⁺ for excretion by the kidneys, increased Na⁺ levels will cause the kidneys to excrete more Ca⁺⁺.

Diet

Limitation of dietary Ca⁺⁺ (e.g., milk, many cheeses, cottage cheese, mustard greens, kale, broccoli) intake to one serving per day.

Hemodialysis in a low-Ca⁺⁺ bath

Sometimes prescribed for severe hypercalcemia to remove Ca⁺⁺ from the plasma.

Pharmacotherapy

Cinacalcet

Initially approved to treat secondary hyperparathyroidism in patients with both renal failure and parathyroid cancer, cinacalcet also performs well in managing primary hyperparathyroidism. Medical treatment for primary hyperparathyroidism is reserved for patients who are poor surgical risks or who have only a mild form of the disease. Ultimate goals of treatment are to provide adequate hydration and reduce serum Ca⁺⁺ levels. Ca⁺⁺ levels greater than 14 mg/dL are life-threatening and necessitate vigorous and immediate treatment if patient is to survive. In secondary hyperparathyroidism, the initial goal is managing the underlying problem, such as renal failure. Unfortunately, even the best management of renal failure does not cure secondary hyperparathyroidism.

Diuretics

Given to prevent volume overload and facilitate diuresis. Loop diuretics (furosemide and bumetanide) are preferred because they increase urinary Ca⁺⁺ excretion. Thiazide diuretics (hydrochlorothiazide, chlorothiazide) are contraindicated because they decrease Ca⁺⁺ excretion.

Oral phosphate supplements

For patients who have not been on recent glucocorticoid (steroid) therapy to help decrease bone resorption of Ca⁺⁺ and bind Ca⁺⁺ in the intestine to limit Ca⁺⁺ absorption. Because these drugs may cause precipitation of insoluble Ca⁺⁺-phosphate complexes in the soft tissues of the kidneys, lungs, and cardiac conductive system, they are given only to patients with a low serum phosphate level or to those who have normal kidney function. Diarrhea is a common side effect. IV phosphates are avoided except for extreme emergency (Ca⁺⁺ more than 14 mg/dL).

Intramuscular (IM) calcitonin

Decreases bone resorption of Ca⁺⁺ and increases renal clearance. This has limited use, however, because it is short acting and patients commonly become resistant.

IV mithramycin

Inhibits bone resorption and lowers serum and urine Ca⁺⁺ levels. This is the drug of choice for treatment of severe hypercalcemia because it is more effective and works more rapidly than calcitonin. Effects usually are seen within 2 hr. Side effects include bleeding abnormalities, hypocalcemia, and nausea.

IV etidronate

As effective as mithramycin in controlling hypercalcemia but has fewer side effects.

IV etidronate with IV pamidronate

Concomitant use of both medications results in better control of hypercalcemia than using etidronate alone.

Oral steroids

Given for their calciuric effect and to decrease Ca⁺⁺ absorption in the presence of vitamin D intoxication. To avoid immunosuppressive effects of these drugs, they are given in as small a dose as it takes to achieve therapeutic effects. This treatment usually is reserved for hypercalcemia associated with hematologic malignancies.

Nursing Diagnoses and Interventions

Impaired physical mobility

related to neuromuscular weakness and joint pain secondary to increased serum Ca⁺⁺ and altered phosphate levels

Desired outcome

Within 2 days after treatment/interventions, patient demonstrates progression to his or her baseline or optimal level of mobility with decreasing evidence of weakness or joint pain.

Nursing Interventions

♦ Administer analgesics and antiinflammatory agents as prescribed to minimize discomfort and enhance effectiveness of prescribed or necessary activity. Time exercise activity to coincide with peak effectiveness of the medication.

♦ Adjust activity to patient’s tolerance and provide rest periods at frequent intervals. Discuss importance of activity with patient, and set realistic short-term and long-term goals in clearly understood terms (e.g., “Ambulate the length of the hall three times, four times a day”). Conserves energy.

♦ Assist with ambulation as necessary. Provide a walker or cane if appropriate. For patients undergoing IV therapy, provide a stable rolling IV pole to prevent falls or injury.

♦ Request physical therapy and occupational therapy consultations to facilitate gradual increase in patient’s muscular strength and endurance.

Risk for deficient fluid volume

related to osmotic diuresis, vomiting, or diarrhea caused by oral phosphates

Desired outcome

Patient remains normovolemic as evidenced by balanced I&O, urinary output 30 mL/hr or more, good skin turgor, moist tongue and mucous membrane, brisk capillary refill (less than 2 sec), and BP 90/60 mm Hg or greater or within patient’s baseline.

Risk for trauma (pathologic fractures)

related to bone demineralization

Desired outcome

Patient remains free of symptoms of pathologic fractures.

Nursing Interventions

♦ Keep bed in its lowest position, keep walkway free of clutter, and assist patient with ambulation and any strenuous activity to minimize risk of pathologic fractures from falls.

♦ Assess each extremity daily for movement, pain, swelling, or deformity. These findings may signal pathologic fracture.

♦ Notify health care provider of patient complaints of back or chest pain. May signal vertebral or rib fracture.

♦ Instruct unstable patient to request help when getting out of bed. Promote use of a cane or walker, and keep call light within patient’s reach to minimize risk for falls.

♦ Pad side rails for patients with severe bone pathology to help prevent fractures.

♦ Apply chest restraints and/or mitts carefully for patients who are severely confused and may attempt to leave the bed, or arrange for significant other to sit with patient to minimize risk for injury or falls.

Risk for constipation

related to decreased peristalsis associated with increased serum Ca⁺⁺ level

Desired outcomes

After receiving instructions, patient verbalizes knowledge of measures that promote bowel movement. Within 2-3 days of intervention, patient relates bowel elimination within his or her normal pattern.

Ineffective protection

related to risk for hypercalcemia, hypocalcemia, tetany, and thyroid storm secondary to surgical procedure or gland manipulation

Desired outcomes

Optimally, patient remains free of symptoms of hypercalcemia, hypocalcemia, tetany, and thyroid storm, as evidenced by respiratory rate (RR) 12-20 breaths/min with normal depth and pattern (eupnea); orientation to person, place, and time; absence of Chvostek’s and Trousseau’s signs; normal strength and motion in all extremities; heart rate (HR) 60-100 beats per minute (bpm); and normothermia. If hypercalcemia, hypocalcemia, tetany, or thyroid storm occurs, the abnormality is detected and reported promptly.

Nursing Interventions

♦ Monitor for signs of hypercalcemia. Signs include nausea, vomiting, anorexia, abdominal pain, weakness, thirst, dyspnea, and coma. Hypercalcemia can be caused by increased release of PTH secondary to surgical manipulation of the gland.

♦ Monitor for numbness and tingling around the mouth. Also be alert to indicators of tetany: muscle twitching, painful tonic muscle spasms, and grimacing facial spasms. Two tests to assess for tetany are Chvostek’s and Trousseau’s signs. Chvostek’s sign is elicited by tapping the face just below the temple where the facial nerve emerges. The sign is positive if twitching occurs along the nose, lip, or side of the face. Trousseau’s sign is tested by applying BP cuff to the arm, inflating it to slightly higher than SBP, and leaving it inflated for 1-4 min. Carpopedal spasms are indicative of hypocalcemia. Report significant findings to health care provider. These are early signs of hypocalcemia.

♦ Keep IV Ca⁺⁺ readily available for prescribed treatment of hypocalcemia.

♦ Monitor for signs of thyroid storm, including tachycardia, agitation, and hyperpyrexia. Immediately report presence of these signs to health care provider. Although thyroid storm occurs rarely, it can be caused by a sudden release of excessive amounts of thyroid hormone into the bloodstream from gland manipulation during surgery.

Acute pain

Chronic pain

related to surgical procedure or to arthralgia caused by bone demineralization

Desired outcomes

Within 1 hr of intervention, patient’s subjective perception of pain decreases, as documented by pain scale. Objective indicators, such as grimacing, are absent or diminished.

Nursing Interventions

♦ Monitor for pain, noting and documenting intensity, character, and precipitating factors. Devise a pain scale with patient that rates discomfort from 0 (no pain) to 10 (worst pain).

♦ Administer analgesics as prescribed, and document their effectiveness.

♦ Remind patient to notify staff as soon as discomfort occurs so that analgesics can be administered before pain becomes too severe. Early treatment of pain results in better pain control.

♦ Administer analgesics 30-60 min before scheduled activities such as turning or ambulation to minimize pain during such activities.

♦ Teach patient to clasp hands behind neck during postoperative moving to minimize stress on the incision and thus control pain.

♦ Teach gentle ROM exercises for the neck, as well as assisted or active ROM for painful joints to maintain movement and help minimize pain.

♦ Provide comfort measures such as a foam mattress and a foot cradle to minimize pressure on the extremities.

♦ Provide back rubs, especially at bedtime, to reduce discomfort from prolonged bed rest and promote relaxation.

♦ For additional pain interventions, see this nursing diagnosis in “Pain,” p. 13.

Deficient knowledge

related to risk for side effects from prescribed steroids, phosphate supplements, and mithramycin

Desired outcome

Patient verbalizes knowledge of side effects of prescribed medications and importance of notifying health care provider if these side effects occur.

Nursing Interventions

♦ Assess patient’s facility with language; engage an interpreter or provide language-appropriate written materials if necessary.

♦ Teach patient about prescribed medications:

• Steroids: Teach importance of monitoring for side effects, including frequent BP checks for hypertension, assessment for mental changes, daily weight measurement for evidence of weight gain, and blood tests for hyperglycemia.

• Phosphate supplements: Explain that diarrhea is a common side effect.

• Mithramycin: Teach that lower extremity petechiae may signal thrombocytopenia; jaundice signals hepatocellular necrosis; and tetany occurs with hypocalcemia. Explain that urinalysis results must be monitored for evidence of proteinuria.

♦ Explain importance of notifying health care provider promptly if side effects from prescribed medications occur.

♦ Teach patient that extreme changes in the patient’s condition can be life-threatening and must be managed promptly. Patients who cannot reach their health care provider by phone or who cannot get an appointment should proceed to a hospital emergency department for immediate assistance.

Patient-Family Teaching and Discharge Planning

Include verbal and written information about:

♦ Dietary considerations, including Ca⁺⁺ restriction, increased fluids, and possibly increased Na⁺. As appropriate, arrange for a dietary consultation to help patient with meal planning and integration of individual restrictions into family meals.

♦ Medical follow-up: Emphasize importance and confirm date and time of next appointment.

♦ Signs and symptoms of hypocalcemia and hypercalcemia (see Ineffective protection, p. 392), which necessitate medical attention if they occur.

♦ Prescribed medications, including drug names, purpose, dosage, schedule, precautions, and potential side effects. Also discuss drug/drug, food/drug, and herb/drug interactions.

♦ Management of incision if surgery was performed, including indications of wound infection (e.g., erythema, local warmth, swelling, discharge, pain, fever) and review of surgeon’s instructions regarding wound cleaning and when showering may ensue.

Hypoparathyroidism

Overview/Pathophysiology

Hypoparathyroidism results from the decreased production of parathyroid hormone (PTH). Most commonly this disorder is iatrogenic, caused by damage to or accidental removal of the parathyroid glands during thyroid surgery or radioactive iodine treatment for hyperthyroidism. Damage may be temporary or permanent. If injury occurs in the absence of gland removal, the tissue generally recovers within a period of months and returns to normal functioning. Familial or autoimmune factors also can be significant in the development of hypoparathyroidism because of deficient PTH receptors in target tissues.

Collaborative Management

Ca⁺⁺ supplements

Given either by the oral (PO) or IV route, with dosage adjustments based on serum levels of Ca⁺⁺.

PTH injections

Given to replace lost PTH.

Vitamin D preparations

Facilitates absorption of Ca⁺⁺ from the gastrointestinal (GI) tract.

Sedatives (phenobarbital) and magnesium sulfate

Minimize tetany and seizures.

Aluminum hydroxide gels

Bind phosphorus in the intestines and decreases serum phosphate levels.

Diet

High in Ca⁺⁺ (1 qt milk/day) and low in phosphorus (limit meat, poultry, fish, eggs, cheese, dried beans, and cereals). If hyperphosphatemia persists, it may be necessary to restrict dairy products and egg yolks and provide oral Ca⁺⁺ supplements. Foods high in oxalate, which binds to Ca⁺⁺, also should be avoided. These include beets, figs, nuts, spinach, black tea, and chocolate.

Nursing Diagnoses and Interventions

Activity intolerance

related to weakness and fatigue secondary to decreased cardiac contractility

Desired outcome

During activity, patient rates perceived exertion at 3 or less on a 0-10 scale and exhibits cardiac tolerance to activity, as evidenced by heart rate (HR) 20 beats per minute (bpm) or less over resting heart rate HR; SBP 20 mm Hg or less over or under resting SBP; respiratory rate (RR) 12-20 breaths/min with normal depth and pattern (eupnea); normal skin color; warm and dry skin; and absence of crackles (rales), murmurs, chest pain, and new dysrhythmias.

Ineffective protection

related to risk for tetany, respiratory distress, and seizures secondary to hypocalcemia

Desired outcome

Patient verbalizes orientation to person, place, and time and is free of symptoms of injury caused by tetany, respiratory distress, and seizures.

Nursing Interventions

♦ Assess for signs of hypocalcemia: tingling around mouth and in hands, muscle twitching, painful tonic muscle spasms, grimacing facial spasms, and Chvostek’s and Trousseau’s signs (see p. 392). Report significant findings to health care provider. These are indicators of tetany.

♦ Monitor for respiratory distress, including stridor, wheezing, and dyspnea; report significant findings to health care provider immediately.

Only gold members can continue reading. Log In or Register to continue

Stay updated, free articles. Join our Telegram channel

Tags: Manual of Medical-Surgical Nursing Care Nursing Interventions an

Sep 1, 2016 | Posted by admin in NURSING | Comments Off

Fastest Nurse Insight Engine

Endocrine Disorders

Section Two Disorders of the Parathyroid Glands