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Related to Pituitary Tumor: Pituitary adenoma
|Mean LOS:||5.7 days|
|Description:||SURGICAL: Adrenal and Pituitary Procedures With CC or Major CC|
|Mean LOS:||4.9 days|
|Description:||MEDICAL: Endocrine Disorders With CC|
Pituitary tumors, which are generally anterior lobe adenomas, make up from 10% to 15% of all intracranial neoplasms. Approximately 15% of all intracranial tumors are pituitary tumors that cause symptoms. Approximately 7% of all brain cancers develop from the pituitary gland. About 8,000 new pituitary tumors are diagnosed each year in the United States, but very few are fatal. Microadenomas are smaller than 1 cm, and macroadenomas are larger than 1 cm. While microademonas may cause complications because of overproduced pituitary hormones, they generally do not damage surrounding tissue. Because of their size, macroadenomas can be locally invasive, often damaging normal pituitary tissue and nearby nerves and parts of the brain. Most pituitary tumors are nonmalignant, but because of their invasiveness, they are considered neoplastic conditions.
Some 75% of pituitary adenomas are functional (hormone-producing) tumors. The hormone produced by an adenoma strongly influences its signs and symptoms and thus the choice of diagnostic tests and treatment. Adenomas are classified as prolactinomas, or prolactin-producing adenomas (30% of pituitary tumors); somatotrophin-secreting adenomas (15% to 20%); corticotrophin, or adrenocorticotropic hormone (ACTH)–secreting adenomas (10% to 15%); gonadotrophin-secreting adenomas (very small percentage); thyrotropin-secreting adenomas (very small percentage); null cell adenomas (15% to 20%); and plurihormonal (mixed-cell) adenomas. The outlook for survival also varies, depending on what kind of adenoma exists. Other types of tumors include craniopharyngiomas (benign tumors that develop next to the pituitary that do not make pituitary hormones but can disrupt hormone production by compressing the pituitary gland), teratomas, germinomas, and choriocarcinomas (uncommon tumors that occur most often in children or young adults), and Rathke’s cleft cysts and gangliocytomas (uncommon tumors that are usually found in adults).
Pituitary tumors lead to hormone excess, hormone deficiencies, or any combination of imbalances. In addition, as the tumor grows, it replaces normal pituitary gland tissue. Complications from pituitary tumors include loss of hormonal function in all systems of the body and compression of central nervous system (CNS) structures such as the hypothalamus. Complications of surgery include hemorrhage, infection, cerebrospinal fluid (CSF) leak, and diabetes insipidus.
Although the cause of pituitary tumors is unknown, the patient’s heredity may predispose her or him to a tumor.
Most pituitary tumors are sporadic; however, the heritable disorder multiple endocrine neoplasia I (MEN I) is associated with parathyroid, pancreatic, and pituitary tumors. MEN I is transmitted in an autosomal dominant pattern. Low expression of various tumor suppressor genes has been implicated in pituitary tumor growth. Mutations in the aryl hydrocarbon receptor–interacting protein (AIP) or GNAS1 can also cause pituitary adenomas.
Gender, ethnic/racial, and life span considerations
Approximately 70% of pituitary tumors occur in people between ages 30 and 50. Only 3% to 7% occur in people younger than 20, and twice as many females as males have the condition. Women of childbearing age have a higher prevalence of pituitary adenomas than do men. No racial or ethnic considerations have been identified.
Global health considerations
Although no specific data are available, experts note that the global incidence of pituitary tumors is probably similar to that of the United States.
Ask the patient to describe any endocrine or neurological symptoms. Usually, patients give a history of slowly developing, progressive symptoms. They frequently complain of headaches, visual disturbances (blurred vision or double vision progressing to blindness), decreased sexual interest, menstrual irregularities, and impotence. Family members may report CNS changes, such as anxiety, personality changes, seizure activity, and even dementia. Depending on tumor type, patients may describe weakness, fatigue, sensitivity to cold, and constipation.
You may note that the skin has a waxy appearance; fewer than normal wrinkles for the patient’s age; and a decreased amount of body, pubic, and axillary hair. Assess the patient’s skin for hyperpigmentation, oiliness, acne, and diaphoresis. Assessment of visual function is important because pituitary tumors may press on the optic chiasm. Assess the patient’s visual fields, visual acuity, extraocular movements, and pupillary reactions. A classic finding is bitemporal hemianopsia (blindness in the temporal field of vision). Perform an assessment of the cranial nerves. The tumor may involve cranial nerves III (oculomotor, which regulates pupil reaction), IV (trochlear, which along with the abducens regulates conjugate and lateral eye movements), and VI (abducens). Examine the patient’s musculoskeletal structure, determining whether foot and hand size are appropriate for body size; whether facial features are altered, such as thick ears and nose; and whether the skeletal muscles are atrophied.
The patient may have personality changes such as irritability and even occasional hostility. Assess the patient’s interpersonal relationships, the response of significant others, and the patient’s and significant others’ abilities to cope with a potentially serious illness. Patients may be concerned about body image, fertility, and sexual performance.
|Test||Normal Result||Abnormality With Condition||Explanation|
|Growth hormone||< 10 ng/mL||Elevated||Functional (hormone-producing) tumor elevates levels of various hormones|
|Gonadotrophins: Follicle-stimulating hormone||Adult male: 2–18 IU/L; adult female: 5–20 IU/L (follicular or luteal), 30–50 IU/L (midcycle peak)||Elevated||Functional tumor elevates levels of various hormones|
|Luteinizing hormone||Adult male: 2–18 IU/L; adult female: 5–12 IU/L (follicular or luteal), 30–250 IU/L (midcycle peak)||Elevated||Functional tumor elevates levels of various hormones|
|Prolactin||0–20 ng/mL||Elevated||Functional tumor elevates levels of various hormones|
|Thyrotropin (thyroid-stimulating hormone)||1–6.2 μU/mL||Elevated||Functional tumor elevates levels of various hormones|
|ACTH||< 60 pg/mL||Elevated||Functional tumor elevates levels of various hormones|
|Magnetic resonance imaging||No visual evidence of tumors; normal brain structure||Provides visual evidence of tumors||Standard imaging test to identify pituitary tumors; can identify macroadenomas and microadenomas > 3 mm; can locate small abnormalities in pituitary gland unrelated to symptoms; 5%–25% of patients have unrelated minor abnormalities of pituitary gland|
Other Tests: Biopsy of pituitary tissue, glucose, electrolytes, ophthalmological examination
Primary nursing diagnosis
DiagnosisPain (acute) related to pressure from a space-occupying lesion
OutcomesComfort level; Pain control behavior; Pain: Disruptive effects; Pain level
InterventionsPain management; Analgesic administration; Positioning; Teaching: Prescribed activity/exercise; Teaching: Procedure/treatment; Teaching: Prescribed medication
Planning and implementation
The treatment of a pituitary tumor is guided by whether it is a carcinoma or an adenoma. Treatment of adenomas is guided by whether the adenoma is functional, whether it is a microadenoma or a macroadenoma, and which hormone is being secreted. The main treatment for many pituitary tumors is surgery, while medications can relieve symptoms and sometimes shrink the tumor. With larger and more invasive tumors, the likelihood of cure by surgery decreases. The usual operation for pituitary tumors is a transsphenoidal hypophysectomy (removal of the pituitary gland through a surgical incision in the sphenoid bone). The surgery has a low neurological complication rate and leaves no visible scar. Cure rates for microadenomas are greater than 80% but are lower if the tumor is large or if it has invaded nearby nerves or brain tissue.
In a newer procedure, surgeons use endoscopic surgery, operating through a fiberoptic device inserted through an incision in the lining of the nose. This procedure takes less time and causes fewer complications than transsphenoidal hypophysectomy. For larger or more complicated tumors, a craniotomy is required to remove the tumor, but the surgery exposes patients to a higher incidence of permanent neurological complications than with transsphenoidal hypophysectomy. The overall surgical cure rate for patients with growth hormone–secreting adenomas is about 60%. The cure rate is slightly higher for corticotrophin-secreting adenomas because these tend to be smaller tumors. Only complicated prolactinomas are treated surgically.
Complications of pituitary surgery can be serious but, fortunately, are extremely rare. If large arteries, nearby nerves, or nearby brain tissue is damaged, a stroke or blindness is possible. Meningitis can result from damage to the membranes that surround the brain. Much more likely is a temporary onset of diabetes insipidus, which usually resolves itself within 1 to 2 weeks after surgery. Damage to the pituitary leading to hypopituitarism may be unavoidable when treating some macroadenomas, but such damage can be treated by medication.
Postprocedural or postsurgical monitoring of the patient is crucial. Make sure the patient has an adequate airway and is breathing at all times. If you suspect airway compromise (changes in mental status, restlessness, confusion, shortness of breath, stridor, apnea), notify the physician immediately. Check with the surgeon to determine the preferred protocol for endotracheal suctioning. Perform serial neurological assessments to identify changes in mental status, pupil reaction, and strength and motion of the extremities. After surgery, maintain the subarachnoid drainage systems, and note the amount, color, and consistency of all drainage. Position the patient by elevating the head of the bed to 30 to 45 degrees to decrease edema and to promote CSF flow to the lumbar cistern. If the patient is not responsive, position her or him in a side-lying position to facilitate drainage from the mouth.
Explain that the patient needs to avoid leaning forward, blowing the nose, and sneezing. Do not remove the nasal packing until the surgeon requests it. Withhold oral fluid intake in the immediate postoperative period because it may stimulate the vomiting center and contribute to increased intracranial pressure. Provide analgesics to manage pain relief, and if the patient does not experience relief, notify the surgeon so that the medication type or dosage can be altered. If CSF drains from the nose, notify the surgeon immediately, and monitor the patient for signs of a CNS infection (changes in level of consciousness, irritability, fever, foul drainage) or pulmonary infection (fever, pulmonary congestion, yellow or white pulmonary secretions). Monitor the patient for diabetes insipidus owing to a lack of antidiuretic hormone; maintain intake and output records, and notify the physician if a fluid deficit occurs.
|Medication or Drug Class||Dosage||Description||Rationale|
|Prolactin-inhibitor||Varies with drug||Bromocriptine (Alphagan, Parlodel); cabergoline (Dostinex)||Shrinks prolactin-secreting tumors in 1–6 mo; ineffective for treating acromegaly; side effects such as nausea and orthostatic hypotension may preclude use of bromocriptine in some patients|
Other Drugs: Octreotide, lanreotide is used to inhibit growth hormone (somatotrophin) secretion; cyproheptadine is used to inhibit corticotrophin.
To limit the risk of injury before surgery, discuss with the patient the best mechanisms to provide a safe environment if his or her vision is impaired. Provide an uncluttered room with a clear pathway to the bathroom. Encourage the patient to wear well-fitting shoes or slippers when ambulating. Keep the call light within reach of the patient at all times.
Postoperatively, elevate the patient’s head to facilitate breathing and fluid drainage. Do not encourage the patient to cough, as this interferes with the healing of the operative site. Provide frequent mouth care and keep the skin dry. To promote maximum joint mobility, perform or assist with range-of-motion exercises. Encourage the patient to ambulate within 1 to 2 days of the surgery. To ensure healing of the incision site, explain the need to avoid activities that increase intracranial pressure, such as tooth brushing, coughing, sneezing, nose blowing, and bending. Provide a well-organized and stress-free environment. Explain the treatment options and answer questions. Provide periods of uninterrupted rest each day and schedule diagnostic procedures to allow the patient to recover.
Encourage the patient to use nonpharmacologic methods to control any discomfort. Both patients requiring surgery and patients being managed medically have many emotional needs. Provide privacy so that the patient is able to ask questions about her or his sexual function. Expect that patients may experience loss, grief, or anger if they are dealing with sexual dysfunction such as impotence or infertility. The patient may require support and assistance to develop coping strategies.
Evidence-Based Practice and Health Policy
Cheng, S., Al-Agha, R., Araujo, P.B., Serri, O., Asa, S.L., & Ezzat, S. (2013). Metabolic glucose status and pituitary pathology portend therapeutic outcomes in acromegaly. PLOS ONE, 8(9), e73543. doi 10.1371/journal.pone.0073543
- Investigators examined glucose metabolism among 269 patients with a pituitary tumor and found that a greater proportion of patients with pure somatotroph adenomas presented with abnormal glucose metabolism compared to patients with mixed adenomas (48.7% versus 9.7%; p < 0.001).
- Patients with mixed adenomas were also 2.77 times more likely to achieve remission compared to patients with pure somatotroph adenomas (95% CI, 1.49 to 5.136; p < 0.001). In this sample, 54.6% of patients were diagnosed with pure somatotroph adenomas.
- Physical findings of hormone excesses or deficiencies: Decreased body hair, hirsutism, altered secondary sexual characteristics, acromegaly, galactorrhea; vital signs; neurological assessment; visual examination
- Response to therapy: Surgery, radiation, medications, counseling
- Postoperative management: CSF drainage, nasal packing, wound drainage, signs of complications (diabetes insipidus, infection, increased intracranial pressure, hemorrhage, CSF leak, airway compromise)
Discharge and home healthcare guidelines
Be sure the patient understands all medications, including dosage, route, action, and adverse effects. Explain the symptoms of a CSF leak to the patient. Instruct the patient to notify the physician of fluid drainage from the nares or down the back of the throat, increased temperature, unrelieved headaches, photophobia, nausea and vomiting, or a stiff neck. Explain the risk for massive fluid loss through urination (diabetes insipidus) and the need to replace this fluid volume. Instruct the patient on a diet that replaces fluid and electrolytes. Instruct the patient to notify the physician of any excess urination.