Pheochromocytoma is a tumor (90% benign, 10% malignant; 10% bilateral) originating from the chromaffin cells of the adrenal medulla (90% of cases) or from extra-adrenal chromaffin cells found in other tissues e.g. the aorta, ovaries, spleen.
- These tumors may arise in any age, but peaks from ==40 to 50 years of age==.
- There is a high incidence of pheochromocytomas between family members; family members of any affected individual should be screened for the tumor.
- Its familial form may be part of multiple endocrine neoplasia type 2 (MEN2), and as such should be considered in patients who have medullary thyroid carcinoma and parathyroid hyperplasia/tumor.
- Pheochromocytoma results in hypertension for 0.1% of patients with hypertension. Though rare, it is a form of hypertension that is curable by surgery. If unmanaged, it is often fatal.
Assessment Findings
- Triad: headache, diaphoresis, palpitations in patients with hypertension.
- Hypertension, either intermittent or persistent, among other cardiovascular disturbances are common.
- Other symptoms may include tremors, flushing, and anxiety.
- Hyperglycemia may result from epinephrine secretion stimulating liver and muscle glycogen conversion to glucose. Insulin may be required to maintain normal blood glucose levels.
Paroxysmal Form of Pheochromocytoma
- Paroxysms are acute, unpredictable attacks lasting from seconds to hours. The patient may become extremely anxious, tremulous, and weak. These symptoms begin abruptly but subside slowly.
- Headache, vertigo, blurring of vision, tinnitus, air hunger, dyspnea.
- Polyuria, nausea and vomiting, diarrhea, abdominal pain, and feelings of impending doom.
- Palpitations, and tachycardia
- Life-threatening Hypertension: 250/150 mmHg
- Postural Hypotension: systolic blood pressure drops, leading to lightheadedness or dizziness upon standing.
Diagnostic Examination
- Urine and plasma catecholamine and metanephrine (MN, a catecholamine metabolite) testing are the most direct and conclusive.
- If results for the previous tests are inconclusive, a clonidine suppression test may be performed.
- Imaging studies (CT, MRI, UTZ, 131I-metaiodobenzylguanidine [MIBG] scintigraphy) can localize the pheochromocytoma, and if there are multiple present.
Medical Management
- Control: ICU Admission for ECG monitoring and the use of alpha-adrenergic blocking agents e.g. phentolamine (Regitine) or smooth muscle relaxants e.g. sodium nitroprusside (Nipride). These are for control hypertension. Patient preparation often takes 4 to 7 days.
- Treatment: ==Adrenalectomy== for affected adrenal glands.
- Post-bilateral adrenalectomy, corticosteroid replacement is required. Maintain careful attention for hypotension and hypoglycemia.
Nursing Management
- Monitor ECG changes, arterial pressures, fluid and electrolyte balance, and blood glucose levels.
- For urine testing, give verbal and written instructions on collecting a 24-hour urine specimen.
- Encourage follow-up care to monitor for recurrence and therapy evaluation.
- Educate the client on the purpose of corticosteroids, timing, frequency, and the importance of adherence i.e. the negative effects of skipping or stopping therapy.
- Educate the client and their family on checking blood pressure and when to notify the physician.