Pituitary Dysfunction Flashcards
Which physiologic functions do hormones regulate?
Energy production
Temperature regulation
Fluid and electrolyte balance
Stress response
Sexual development
Which organs rely on the hormones secreted by the pituitary gland?
Parathyroids
Thyroid
Adrenals
Pancreas
Testes
Ovaries
Hormones produced in the anterior pituitary
*TSH (thyroid stimulating hormone)
*ACTH (adrenal corticotropic)
LH
FSH
PRL
*GH (growth hormone)
MSH
Hormones produced by the posterior pituitary
*Vasopressin (ADH)
Oxytocin
How is hormone secretion in the pituitary gland regulated?
Endo and neuro systems work together to regulate hormone balance through negative feedback mechanism:
Decreased hormone levels stimulate production
Increased hormone levels inhibit production
Etiology of hypopituitarism
Hypophysectomy (removal of pituitary gland)
Pituitary tumors
Severe malnutrition (anorexia nervosa)
Shock or severe hypotension (Sheehan’s syndrome)
S/S of hypopituitarism
Secondary adrenocortical insufficiency
Hypothyroidism
Deficient growth hormone
Sexual and reproductive disorders:
Men: decreased facial/body hair, libido, impotence
Women: decreased pubic/axillary hair, libido, breast atrophy
Diagnostics for hypopituitarism
CT scan / MRI to look for tumor
Draw hormone levels (one will be very low while other likely not as low)
Interventions for hypopituitarism
Medical: remove cause, replace hormones
Nursing: assessment of organs involved
Patient problems: body image disturbance, sexual dysfunction, ineffective individual coping
*Removal of pituitary gland = lifelong hormone replacement
Two types of hyperpituitarism
Gigantism
Acromegaly
What is gigantism?
Excess GH in children, resulting in overgrowth of long bones
What is acromegaly?
Excess GH in adults, resulting in increased bone thickness and hypertrophy of soft tissue
Causes of hyperpituitarism
Benign pituitary adenoma (GH secreting tumor)
Prolactinomas (form of pituitary tumor)
ACTH secreting tumor
Tumors secreting gonadotropin or TSH
Effects of hyperpituitarism
Rapid growth of all body tissue
Full blown DM (from over-secretion of ACTH)
Destruction of pituitary causing hypopituitarism (tumor encroaches on gland and ruins it)
Pressure on optic nerve causing blindness
S/S of hyperpituitarism
Headaches
Diplopia/blindness
Goiter
Enlargement of organs
*Broad hands and feet
*Increased ring and shoe size
Thickening of skull
*Protruding of supraorbital ridges
*Coarse facial features
*Prognathism
Arthritic changes
DM
Enlarged, but weak skeletal muscles
Lethargy/fatigue
*Deepening voice
Thickened heel pads
Diagnostics for hyperpituitarism
Plasma hormone levels
CT scan
MRI
Angiography
Patient problems for hyperpituitarism
*Body image disturbance r/t altered physical appearance
Sexual dysfunction r/t loss of libido, infertility, impotence
Interventions for hyperpituitarism
*Surgery = #1 tx
Medication therapy
Radiation therapy
What is the surgery for hyperpituitarism?
Transsphenoidal hypophysectomy
Incision in upper lip with long scissors to cut out pituitary gland. Pt will be on hormone replacement for life
Where is ADH produced?
Hypothalamus and stored in/released from posterior pituitary gland
Function of ADH
AKA vasopressin
Acts of renal collecting tubules and results in water reabsorption
Disorders associated with ADH
Diabetes insipidus
SIADH
What is diabetes insipidus?
Deficiency in synthesis or release of ADH
Excess water losses
Two types of DI and what causes each?
Neurogenic: ADH deficiency
Nephrogenic: kidneys insensitive to ADH (can’t respond to it)