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AClITE CARE HANDBOOK FOR PHYSICAL TI-iERAPISTS

highly dependent on the diurnal rhythm of secretion. Normal serum levels

are 5-23 �gldl (8-10 AM) and 3-1 6 �gldl (4-6 I'M).21

•

Twenty-four-hour urinary corticosteroids. Analysis of urine

over a 24-hour period to determine the urinary levels of corticosteroids will provide a rough outline of cortisol output. Also indicated for diagnosing Cushing's or Addison's disease. Normal urine levels are 20-90 �gldl for a 24-hour period.22

•

ACTH levels are usually examined concomitantly with corti-

sol levels, as ACTH secretion from the pituitary gland is necessary for

cortisol secretion from the adrenal glands. Refer to Table 1 1-6 for

details on ACTH measurement.

Androgens

Individual androgen levels can be measured by RIA in the serum or by

metabolic products (17-ketosteroids) in the urine. I •• High concentrations of androgens may result in the following changes in women:

• Hirsutism, which is excessive hair growth in skin zones considered male in distribution (i.e., upper lip, side burns, chin, neck, chest, and lower abdomen)

• Amenorrhea, which is the absence of menstruation in women

older than 16 years of age or the absence of menses for longer than

6 months in women of childbearing age who previously had been

menstruating

• Voice change

• Increased muscle mass

Milleralocorticoids

Mineralocorticoids can be evaluated by testing serum electrolyte levels or plasma renin activity and aldosterone levels.11 Abnormalities of serum electrolyte levels, such as an increased potassium level, provide

a valuable screening tool for mineralocorticoid secretion disorders.

Aldosterone is the primary mineralocorticoid and is controlled by the

renin-angiotensin system. A rise in serum potassium and angiotensin

II results in aldosterone sectetion, which helps to balance Auid and

electrolyte levels. Blood samples of aldosterone are usually taken first

in the early morning, while the patient is still recumbent, and then

again after 4 hours of being awake and active. Normal serum levels of

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671

aldosterone range from 2 to 50 ngldl, depending on whether blood

was taken in the supine or upright position.4,5,1 J

Catecholamilles

Epinephrine and norepinephrine are commonly referred to as catecholamil/es, and their levels are generally measured through 24-hour urine samples. Dopamine, also a catecholamine, is the precursor for

epinephrine and norepinephrine and therefore can also be measured

to reflect rhe amount of carecholamines circulating in the body. However, the preferred screening tool is to measure the amount of catecholamine metabolites in the urine. The primary catecholamine metabolite is called val/illylmal1delic acid (VMA). Normal values for

these substances are as follows4,s:

Dopamine: 65-100 pg per 24 hours

Epinephrine: 1 .7-22.4 pg per 24 hours

Norepinephrine: 12. 1-85.5 pg per 24 hours

Vanillylmandelic acid: 1 .4-6.5 pg per 24 hours

Metabolic Tests

Metabolic tests are described in this section, as glucocorticoids (cortisol) affect carbohydrate, protein, and fat metabolism.

Glucose Toleral/ce Test

A glucose tolerance test was primarily used to diagnose diabetes mellitus; however, because of many confounding variables, it is currently not relied on to establish diabetes mellitus, but rather to help confirm

the diagnosis in certain cases. However, the glucose tolerance test is

the primary method of establishing the diagnosis of gestational diabetes mellirus.4.6

To perform the test, a 75- or 100-g glucose load is given to the

subject in the morning after a l O-hour fast. Blood glucose levels are

then measured at variable time periods, ranging from every half

hour to every hour for the next 2 to 5 hours after the glucose administration. The subject must remain inactive and refrain from smoking throughout the duration of the test. Normally, the blood glucose levels should fall back to baseline values after a 2-hour period. Normal glucose value for a fasting blood sugar (BS) is approximately 70-1 1 0 mgldl.'·4.6

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ACUTE CARE HANDBOOK FOR PHYSICAL THERAPISTS

Adrenal Disorders

Adrenal Insufficiency

Autoimmune dysfunction can lead to destruction of the adrenal cortex (i.e., primary adrenal insuf(iciellcy Ot Addisoll's disease). Additionally, ACTH deficiency from the pituitaty gland can lead to atrophy of the adrenal cortex (secondary adrellal il1sllf(iciellcy). The

net result is an impaired adrenal system with decreased levels of glucocorticoids (cortisols), mineralocorticoids (aldosterone), and androgens. Given the systemic functions of these hormones, Addison's disease can have severe consequences if left untreated. Fortunately,

the incidence is rare.

Cortisol deficiency results in decreased gluconeogenesis (glucose

production), which in turn alters cellular metabolism. Decreased gluconeogenesis also results in hypoglycemia and decreased ability ro respond to stress. Aldosterone deficiency causes fluid and electrolyte

imbalance, primarily as a result of increased water excretion that

leads ro dehydration B."

The following are symproms and physical findings common ro

adrenal insufficiencyl.6.25:

• Weakness, fatigue

• Weight loss, nausea, vomiting, vague abdominal pain

• Muscle and joint pain

• Salt craving in fewer than 20% of patients

• Hyperpigmentation

• Hypotension

Management of adrenal insufficiency typically consists of pharmacologic intervention with any of the following steroids: hydrocortisone (Cortisol, Compound F), hydrocortisone acetate, prednisone (Deltasone), dexamethasone (Decadron, Dexasone), or fludrocortisone (Florinef) '·ls Caution muSt be taken, however, with corticosteroid administration, as corticosteroids can suppress the release of endogenous cortisol from the adrenal gland.2•

Pheochromocytoma

Pheochromocyroma is a rare adrenomcdullary disorder caused by a

rumor of the chromaffin cells in the adrenal medulla, which results in

excess secretion of the carecholamines, epinephrine, and norepineph-

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673

rinc. The occurrence is equal between men and women during their

twenties and thirties. Given the rare occurrence of this tumor, it often

goes undiagnosed. However, proper diagnosis is essential, as the sustained release of catecholamines can be life threatening. Early diagnosis generally has favorable results.6,25,27

Signs and symptoms of pheochromocytoma may include the

following 1.23.25.27:

• Hypertension (sustained or paroxysmal), palpitations, tachycardia, and orthostatic hypotension

• Headache, palpitations, and diaphoresis

• Excessive perspiration

•

crvousness and emotional outbursts or instability

• Elevated blood glucose levels and glucosuria

Management of pheochromocytoma generally consists of surgical

excision of the rumor with preoperative pharmacologic management

with one of the following medications: alpha-adrenergic blocking

agents (e.g., phenoxybenzamine [Dibenzyline], phentolamine [ Regitinel), beta-adrenergic blocking agents (e.g., propranolol [Inderal]), or tyrosine inhi bitors (alphamethlyparatyrosine).8.25.28

Pancreatic Disorders

Diabetes Mellitus

Diabetes mellitus is a syndrome with metabolic, vascular, and neural