ADRENOCORTICAL INSUFFICIENCY (ADDISON’S DISEASE)
Addison’s disease, or adrenocortical insufficiency, results whenadrenal cortex function is inadequate to meet the patient’s need for cortical hormones. Autoimmune or idiopathic atrophy of the adrenal glands is responsible for 80% of cases (Rakel & Bope, 2001). Other causes include surgical removal of both adrenal glands or infection of the adrenal glands. Tuberculosis and histoplasmosis are the most common infections that de-stroy adrenal gland tissue. Although autoimmune destruction has replaced tuberculosis as the principal cause of Addison’s dis-ease, tuberculosis should be considered in the diagnostic workup because of its increasing incidence. Inadequate secre-tion of ACTH from the pituitary gland also results in adrenal insufficiency because of decreased stimulation of the adrenal cortex.
Therapeutic use of corticosteroids is the most common cause of adrenocortical insufficiency (Coursin & Wood, 2002). The symptoms of adrenocortical insufficiency may also result from the sudden cessation of exogenous adrenocortical hormonal therapy, which suppresses the body’s normal response to stress and inter-feres with normal feedback mechanisms. Treatment with daily administration of corticosteroids for 2 to 4 weeks may suppress function of the adrenal cortex; therefore, adrenal insufficiency should be considered in any patient who has been treated with corticosteroids.
Addison’s disease is characterized by muscle weakness, anorexia, gastrointestinal symptoms, fatigue, emaciation, dark pigmenta-tion of the skin, knuckles, knees, elbows, and mucous mem-branes, hypotension, and low blood glucose levels, low serum sodium levels, and high serum potassium levels. Mental status changes such as depression, emotional lability, apathy, and con-fusion are present in 60% to 80% of patients. In severe cases, the disturbance of sodium and potassium metabolism may be marked by depletion of sodium and water and severe, chronic dehydration.
With disease progression and acute hypotension, the patient develops addisonian crisis, which is characterized by cyanosis and the classic signs of circulatory shock: pallor, apprehension, rapid and weak pulse, rapid respirations, and low blood pressure. In ad-dition, the patient may complain of headache, nausea, abdominal pain, and diarrhea and show signs of confusion and restlessness. Even slight overexertion, exposure to cold, acute infections, or a decrease in salt intake may lead to circulatory collapse, shock, and death if untreated. The stress of surgery or dehydration resulting from preparation for diagnostic tests or surgery may precipitate an addisonian or hypotensive crisis.
Although the clinical manifestations presented appear specific, the onset of Addison’s disease usually occurs with nonspecific symptoms. The diagnosis is confirmed by laboratory test results. Laboratory findings include decreased blood glucose (hypoglyce-mia) and sodium (hyponatremia) levels, an increased serum potas-sium (hyperkalemia) level, and an increased white blood cell count (leukocytosis).
The diagnosis is confirmed by low levels of adrenocortical hor-mones in the blood or urine and decreased serum cortisol levels. If the adrenal cortex is destroyed, baseline values are low, and ACTH administration fails to cause the normal rise in plasma cortisol and urinary 17-hydroxycorticosteroids. If the adrenal gland is normal but not stimulated properly by the pituitary, a normal response to repeated doses of exogenous ACTH is seen, but no response follows the administration of metyrapone, which stimulates endogenous ACTH.
Immediate treatment is directed toward combating circulatory shock: restoring blood circulation, administering fluids and corticosteroids, monitoring vital signs, and placing the patient in a recumbent position with the legs elevated. Hydrocortisone (Solu-Cortef) is administered intravenously, followed with 5% dextrose in normal saline. Vasopressor amines may be required if hypotension persists.
Antibiotics may be administered if infection has precipitated adrenal crisis in a patient with chronic adrenal insufficiency. Ad-ditionally, the patient is assessed closely to identify other factors, stressors, or illnesses that led to the acute episode.
Oral intake may be initiated as soon as tolerated. Gradually, intravenous fluids are decreased when oral fluid intake is adequate to prevent hypovolemia. If the adrenal gland does not regain function, the patient needs lifelong replacement of corticosteroids and mineralocorticoids to prevent recurrence of adrenal insuffi-ciency. The patient will require additional supplementary ther-apy with glucocorticoids during stressful procedures or significant illnesses to prevent addisonian crisis (Coursin & Wood, 2002). Additionally, the patient may need to supplement dietary intake with added salt during times of gastrointestinal losses of fluids through vomiting and diarrhea.
The health history and examination focus on the presence of symptoms of fluid imbalance and on the patient’s level of stress. To detect inadequate fluid volume, the nurse monitors the blood pressure and pulse rate as the patient moves from a lying to a standing position. The nurse assesses the skin color and turgor for changes related to chronic adrenal insufficiency and hypovolemia. Other key assessments include checking for weight changes, mus-cle weakness, and fatigue and investigating any illness or stress that may have precipitated the acute crisis.
The patient at risk is monitored for signs and symptoms indica-tive of addisonian crisis. These symptoms are often the manifes-tations of shock: hypotension; rapid, weak pulse; rapid respiratory rate; pallor; and extreme weakness. The patient with addisonian crisis is at risk for circulatory collapse and shock; therefore, physical and psy-chological stressors must be avoided. These include exposure to cold, overexertion, infection, and emotional distress.
The patient with addisonian crisis requires immediate treat-ment with intravenous administration of fluid, glucose, and elec-trolytes, especially sodium; replacement of missing steroid hormones; and vasopressors. During acute addisonian crisis, the patient must avoid exertion; therefore, the nurse anticipates the patient’s needs and takes measures to meet them.
Careful monitoring of symptoms, vital signs, weight, and fluid and electrolyte status is essential to monitor the patient’s progress and return to a precrisis state. To reduce the risk of future episodes of addisonian crisis, efforts are made to identify and re-duce the factors that may have led to the crisis.
To provide information about fluid balance and the adequacy of hormone replacement, the nurse assesses the patient’s skin turgor, mucous membranes, and weight while instructing the patient to report increased thirst, which may indicate impending fluid im-balance. Lying, sitting, and standing blood pressures also provide information about fluid status. A decrease in systolic pressure (20 mm Hg or more) may indicate depletion of fluid volume, es-pecially if accompanied by symptoms. The nurse encourages the patient to consume foods and fluids that will assist in restoring and maintaining fluid and electrolyte balance; along with the dietitian, the nurse assists the patient to select foods high in sodium during gastrointestinal disturbances and very hot weather.
The nurse instructs the patient and family to administer hor-mone replacement as prescribed and to modify the dosage dur-ing illness and other stressful occasions. Written and verbal instructions are provided about the administration of mineralo-corticoid (Florinef) or corticosteroid (prednisone) as prescribed.
Until the patient’s condition is stabilized, the nurse takes pre-cautions to avoid unnecessary activity and stress that could pre-cipitate another hypotensive episode. Efforts are made to detect signs of infection or the presence of other stressors. Even minor events or stressors may be excessive in patients with adrenal in-sufficiency. During the acute crisis, the nurse maintains a quiet, nonstressful environment and performs all activities (eg, bathing, turning) for the patient. Explaining all procedures to the patient and family will reduce their anxiety. Explaining the rationale for minimizing stress during the acute crisis assists the patient to in-crease activity gradually.
Because of the need for lifelong re-placement of adrenal cortex hormones to prevent addisonian crises, the patient and family members receive explicit verbal and written instructions about the rationale for replacement therapy and proper dosage. Additionally, they are instructed about how to modify the medication dosage and increase salt intake in times of illness, very hot weather, and other stressful situations. The pa-tient also learns how to modify diet and fluid intake to help main-tain fluid and electrolyte balance.
The patient and family are frequently prescribed preloaded, single-injection syringes of corticosteroid for use in emergencies. Careful instructions about how and when to use the injection are also provided. It is important to instruct the patient to inform other health care providers, such as dentists, about the use of cor-ticosteroids, to wear a medical alert bracelet, and to carry in-formation at all times about the need for corticosteroids. If the patient with Addison’s disease requires surgery, careful adminis-tration of fluids and corticosteroids is necessary before, during, and after surgery to prevent addisonian crisis.
The patient and family need to know the signs of excessive or insufficient hormone replacement. The development of edema or weight gain may signify too high a dose of hormone; postural hypotension (decrease in systolic blood pressure, lightheadedness,dizziness on standing) and weight loss frequently signify too low a dose (Chart 42-9).
Although most patients can return to their joband family responsibilities soon after hospital discharge, others cannot do so because of concurrent illnesses or incomplete recov-ery from the episode of adrenal insufficiency. In these circum-stances, a referral for home care enables the home care nurse to assess the patient’s recovery, monitor hormone replacement, and evaluate stress in the home. The nurse assesses the patient’s and family’s knowledge about medication therapy and dietary modi-fications. A home visit also allows the nurse to assess the patient’s plans for follow-up visits to the clinic or physician’s office. The nurse reminds the patient and family about the importance of par-ticipating in health promotion activities and health screening.
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