In this article, we explain hypo- and hyperpituitarism, which are disorders resulting from improper pituitary gland function. We also cover the procedure called hypophysectomy, which is the removal of the pituitary gland. Knowing the pathophysiology, signs/symptoms, nursing care, and patient teaching for these two disorders will be key for Med-Surg exams and nursing practice.
Medical-Surgical Nursing - Flashcards
Hypopituitarism
What is hypopituitarism?
Hypopituitarism is a disorder where there is a deficiency in one or more of the pituitary gland hormones. If you remember from our pituitary gland overview, this master gland releases six hormones from the ANTERIOR:
- Thyroid-stimulating hormone (TSH)
- Prolactin
- Follicle-stimulating hormone (FSH)
- Luteinizing hormone (LH)
- Adrenocorticotropic hormone (ACTH)
- Growth hormone (GH)
And two hormones from the POSTERIOR pituitary gland:
When the body has a deficiency in one or more of these eight, this can cause a lot of problems. The most common hormone deficiencies resulting in hypopituitarism are GH, FSH, and LH.
Pathophysiology of hypopituitarism
It’s most common for hypopituitarism to be caused by an issue with the pituitary gland itself. This is easy to remember. Pituitarism — pituitary gland. The patient may have a pituitary tumor, a congenital defect, or a traumatic injury to the pituitary gland.
More rarely, hypopituitarism is caused by an issue with the hypothalamus. In Endocrine Video 3 on GH, oxytocin and prolactin, Cathy teaches these endocrine hormone pathways:
- The hypothalamus releases corticotropin-releasing hormone (CRH), which causes the anterior pituitary gland to release ACTH.
- The hypothalamus produces thyrotropin-releasing hormone (TRH), which causes the anterior pituitary gland to release TSH.
- The hypothalamus releases growth hormone-releasing hormone (GHRH), which causes the anterior pituitary gland to release GH.
- The hypothalamus secretes gonadotropin-releasing hormone (GnRH), which causes the anterior pituitary gland to produce LH and FSH.
- The hypothalamus creates ADH and then it is stored in the pituitary gland to be released.
Notice that 5 out of the 8 hormones released by the pituitary gland start in the hypothalamus. It makes sense that a problem with the hypothalamus could lead to a deficiency of one of those pituitary hormones. But usually, it’s a problem with the pituitary gland.
Signs and symptoms of hypopituitarism
Hypopituitarism can result from a deficiency in one or more of eight hormones. Therefore, there are a wide variety of signs and symptoms that are possible with hypopituitarism, depending on which of the hormones’ production is affected.
The most common hormone deficiency behind hypopituitarism is GH, so delayed growth and development is a common sign.
With hypopituitarism, another common deficiency is FSH and LH. Remember that FSH and LH are responsible for the production of sex hormones estrogen, progesterone and testosterone. So, deficiencies in FSH and LH can lead to decreased sexual function, and symptoms like amenorrhea (lack of menstrual period) in women and impotence in men.
TSH is responsible for stimulating the thyroid to prompt it to produce thyroid hormones T3 and T4. So with a deficiency of TSH, the patient can then have a deficiency of T3 and T4, and may show the signs and symptoms of hypothyroidism. Thus, hypopituitarism with deficient TSH can cause secondary or tertiary hypothyroidism. Signs of hypothyroidism include weight gain, hypotension, bradycardia, lethargy, cold and intolerance.
ACTH triggers the adrenal cortex to release cortisol, aldosterone and other androgens. So when there is a deficiency in ACTH, this can lead to a deficiency of those hormones, which is known as adrenocortical insufficiency or adrenal insufficiency. Signs of adrenocortical insufficiency include fatigue, weakness, weight loss, hypoglycemia, and hyponatremia.
Lab values associated with hypopituitarism
Pituitary hormone levels will be measured, but also the target hormones. Cathy covered the expected lab values for T3, T4, and TSH in the previous video in this series.
Diagnosis of hypopituitarism
ACTH stimulation test
Remember, ACTH is one of the hormones released by the pituitary gland that causes the adrenal gland to release cortisol.
If we give a patient an injection of ACTH, and their adrenal glands successfully produce cortisol in response (determined via a blood test), we know it was a problem with the pituitary gland. The adrenal glands were just waiting for enough ACTH to function properly. So, if we know it’s a problem with the pituitary gland, that’s how we diagnose hypopituitarism.
However, if the patient gets the injection of ACTH, and they do not produce cortisol, we know it’s a problem with the adrenal glands themselves. The adrenal glands got what they needed, and were not able to complete their mission.
CT/MRI
A CT scan or MRI can also be used to diagnose hyperpituitarism. These tests will help identify any kind of tumor or abnormality (e.g., trauma, defect) in the pituitary gland.
Treatment of hypopituitarism
Treating hyperpituitarism requires hormone replacement therapy. Sometimes this therapy may be done with the pituitary hormones, and sometimes with the target hormones.
Thyroid replacement hormones
Levothyroxine (T4) is a synthetic thyroid hormone medication for hypothyroidism. Levothyroxine can be used to treat hyperpituitarism when there is a deficiency in TSH. Since TSH is required for the thyroid to produce T3/T4, if TSH is deficient, synthetic thyroid hormones may be needed.
Growth hormone
When a patient has hypopituitarism with GH deficiency, they may need a growth hormone replacement medication in the form of somatropin.
Corticosteroids
When a patient has hypopituitarism with ACTH deficiency, they may have a resulting deficiency in cortisol; so they may need a replacement medication for this. These are called corticosteroids or glucocorticoids and include prednisone, hydrocortisone, methylprednisolone, and dexamethasone.
Later in this series you will learn that one of the key medications given to a patient with adrenocortical insufficiency is hydrocortisone.
Dexamethasone, basically synthetic cortisol, is also used in the dexamethasone suppression test to diagnose Cushing’s syndrome.
Sex hormones
If a patient has hypopituitarism with FSH or LH deficiency, they may also be deficient in sex hormones. Thus, they may need to take replacement sex hormone medications like estradiol or testosterone.
These medications and more are covered in our Pharmacology flashcards for nursing students.
Hyperpituitarism
Pathophysiology of hyperpituitarism
Hyperpituitarism usually starts with a pituitary adenoma, which is a benign tumor in the pituitary gland, or tissue hyperplasia, which is an overgrowth of tissue. Either the adenoma or the tissue usually resides in the anterior pituitary gland, compressing the brain tissue and causing increased secretion of GH, prolactin and ACTH.
Signs and symptoms of hyperpituitarism
Hyperpituitarism symptoms can include intracranial pressure due to the compressed brain tissue. This pressure can lead to headaches, nausea and vomiting.
Hyperpituitarism with growth hormone excess can result in symptoms like the hormone disorder acromegaly as well as arthralgia, which is joint pain.
Hyperpituitarism with ACTH excess results in excess cortisol, so patients may have signs and symptoms of Cushing’s disease.
Hyperpituitarism with excess prolactin can lead to symptoms of sexual dysfunction, like loss of sex drive. Because prolactin is the hormone that promotes lactation, excess prolactin can also lead to abnormal lactation.
Diagnosis of hyperpituitarism
To diagnose hyperpituitarism, the patient may need a CT scan or MRI, which will show the adenoma or tissue hyperplasia on the pituitary gland.
Treatment of hyperpituitarism
The surgery for hyperpituitarism is a hypophysectomy, which is removal of part or all of the pituitary gland.
A medication that can be used for hyperpituitarism with growth hormone or prolactin excess, is the dopamine agonist levodopa/carbidopa. Levodopa and carbidopa help to inhibit growth hormone and prolactin secretion. Need to remember levodopa/carbidopa? Check out our Pharmacology flashcards for nursing students!
Another medication for hyperpituitarism with GH excess is somatostatin, which is a medication for acromegaly. Somatostatin is actually a naturally-occurring hormone in the body that’s also known as growth hormone-inhibiting hormone.
Hypophysectomy
What is a hypophysectomy?
A hypophysectomy is a brain surgery to remove all or part of the pituitary gland. A transsphenoidal hypophysectomy is when the gland is removed through the nasal cavity, which is the more common approach. Sometimes, the hypophysectomy needs to go through the oral cavity, so an incision is made under the top lip.
Nursing care following a hypophysectomy
After a hypophysectomy procedure, the patient’s nose will drain. It’s important to monitor that drainage for signs and symptoms of a cerebrospinal fluid (CSF) leak.
One sign of CSF leak is a halo sign in the drainage. This means there is clear or bloody fluid in the center of the drainage, but a yellow ring outside that drainage. If you see this halo sign, it can mean the patient has a CSF leak.
Another sign of CSF leak is if the patient complains of a headache and also indicates that their drainage tastes sweet. If you test the drainage and it’s positive for glucose, that is another sign of CSF leak and will need to be further investigated.
Patient teaching following a hypophysectomy
After a patient has a hypophysectomy, it’s important as a med-surg nurse to teach them a few things they will need to know for their recovery. While a patient is healing from their hypophysectomy, they need to avoid activities that increase intracranial pressure. Activities that increase intracranial pressure include coughing, sneezing, blowing their nose, bending at the waist, and straining during bowel movements. With these patients, you will definitely be administering stool softeners and other options to help prevent straining during bowel movements.
Following a hypophysectomy, it will be important to let your patient know that a decreased sense of smell is expected for about the first month after the procedure. It’s also recommended the patient not brush their teeth for two weeks, especially if the procedure was performed through the oral cavity. It is okay for the patient to floss and rinse their mouth.
Finally, the patient must understand that they will need lifelong hormone replacement therapy after a hypophysectomy. The pituitary gland, or part of it, is gone and it will not be producing those hormones. Hormones that may need to be replaced include cortisol in the form of a glucocorticoid, and thyroid hormones.
Cathy’s teaching on these topics is intended to help prepare you for Medical-Surgical nursing exams. The Medical-Surgical Nursing video series is intended to help RN and PN nursing students study for nursing school exams, including the ATI, HESI and NCLEX.
1 comment
Thank you for explaining this content so clearly making it much easier to understand. I love your videos Cathy they have been very instrumental in my success as a nursing student.
Thank you Thank you!