PITUITARY GLAND

Where is it located??? Name its’ 3 parts or sections. What hormones are secreted by the

pituitary gland???

Pituitary Gland

Anterior Pituitary(adenohypophysis) SECRETES 6+ HORMONES:

ACTH (adrenocorticotropic hormone) aka (corticotrphin)

release of cortisol in adrenal glands TSH (thyroid stimulating hormone)

aka (thyrotropin) release of T3 & T4 in thyroid gland GH (growth hormone)

aka (somatotropin) stimulates growth of bone/tissue

FSH (follicle stimulating hormone) stimulates growth of ovarian follicles &

spermatogenesis in males

LH (lutenizing hormone)regulates growth of gonads &

reproductive activities

Prolactin aka (luteotropin/mammotropin)

promotes mammary gland growth and milk secretion

ANTERIOR PITUITARY(adenohypophysis)

Positive vs Negative Feedback Mechanisms Give some examples of

Negative Positive

Anterior HYPERpituitary Disorders ETIOLOGY

Primary: the defect is in the gland itself which releases that particular hormone that is too much or too little.

Example: Secondary: defect is somewhere outside

of gland

i.e. GHRH from hypothalamus

TRH from hypothalamus

Pituitary Tumors

10% OF ALL BRAIN TUMORS What are the diagnostic tests to

diagnose a pituitary tumor? tumors usually cause hyper release of

hormones

(Recall all hormones)

Anterior HYPERpituitary Disorders

What would happen if you had TOO MUCH secretion of prolactin?

Too much release of Lutenizing Hormone (LH)?

Anterior PituitaryHYPERfunctioning What would happen if you had too

much growth hormone secretion???

Too Much Growth Hormone

GIGANTISM IN CHILDREN skeletal growth; may grow

up to 8 ft. tall and > 300 lbs ACROMEGALY IN ADULTS

enlarged feet/hands, thickening of bones, prognathism, HTN, wt. gain, H/A, visual disturbances, diabetes mellitus, enlargement of the heart and liver

GIGANTISM IN CHILDREN

ACROMEGALY IN ADULTS

What assessment findings would the nurse document?

Medical Interventions for Pituitary Tumors Medications

*Parlodel (bromocriptine) to ________ & GH levels.

Radiation therapy external radiation will bring down GH

levels 80% of time

*Neurosurgery: procedure called “transsphenoidal

hypophysectomy”; New Method

Most common method: incision is made thru floor of nose into the sella turcica.

Transsphenoidal Hypophysectomy

Nursing Management &Nursing Diagnosis Pre op hypophysectomy

Anxiety r/t body changes fear of unknown brain involvement chronic condition with life long care

Nursing Management &Nursing Diagnosis

Sensory-perceptual alteration r/t visual field cuts diplopia secondary to pressure on optic

nerve.

Alteration in comfort (headache) r/t tumor growth/edema

Nursing Management &Nursing Diagnosis Knowledge deficit r/t post-op teaching

pain control ambulation hormone replacement activity

Incisional disruption after transsphenoidal hypophysectomy

Avoid bending and straining X 2 months post transsphenoidal hypophysectomy,

Use stool softeners Avoid coughing Saline mouth rinses No toothbrushes for 7-10 days

Post-op CSF Leak where sella turcica was entered

any clear rhinorrhea - test for glucose + glucose = CSF Leak

Notify physician HOB 30 degrees Bedrest

Post op problems cont.

Periocular edema/ecchymosis Headaches Visual field cuts/diplopia Meningitis

Post operative care

Post-op complications of hormone deficiency: What would happen if you didn’t

have enough ADH? What is that disorder called?

Other deficiency:

Decrease ACTH will require cortisone replacement due to decrease glucocorticoid production.

Can you live without glucocorticoids????

Other deficiency:

in sex hormones can lead to infertility due to decreased production of ova & sperm

What were those hormones called again?

Anterior PituitaryHYPOfunction Etiology (rare disorder) may be due to

disease, tumor, or destruction/removal of the gland.

Diagnostic tests CT Scan Serum hormone levels

S & S Anterior Pituitary HYPOfunctioning

GH FSH/LH Prolactin ACTH TSH

Medical Management

neurosurgery -- removal of tumor

radiation - tumor size

hormone replacement cortisol, thyroid, sex hormones

Nursing Management

Assessment of S & S of hypo or hyper

functioning hormone levels Teaching-Compliance with hormone

replacement therapy Counseling and referrals Support medical interventions

Posterior Pituitary(Neurohypophysis)

What hormones are released by the posterior pituitary?

_____ & _____are released when signaled by hypothalamus

ADH (Vasopressin/AVP)

secreted by cells in the hypothalmus and stored in posterior pituitary

acts on distal & collecting tubules of the kidneys making more permeable to H20 -- or volume excreted?

Bonus Round...

Under what conditions is ADH released?

ADH has vasoconstrictive or vasodilation action???

http://www.cvphysiology.com

Oxytocin

Controls lactation & stimulates uterine contractions

‘Cuddle hormone’Research links oxytocin and socio-sexual behaviors

Posterior HYPERpituitary Disorders SIADH (TOO MUCH ADH!!)

small cell lung cancer, Ca duodenum/pancreas, trauma, pulmonary disease, CNS disorders

drugs -- Vincristine, nicotine, general anesthetics, tricyclic antidepressants

Think tank:

If you have increased ADH secretion...

What would the clinical signs/symptoms be?

Clinical manifestations-SIADH Weight gain or weight loss? or urine output?

or serum Na levels?

thirst weakness muscle cramps H/A Diarrhea

If hyponatremia worsensdevelopment of neurological manifestations

lethargy decrease tendon reflexes abdominal cramping, vomitting coma seizures

Diagnostic Tests-SIADH

Serum Na+ <134meq/l

Serum osmolality <280 OSM/kg H2O

urine specific gravity >1.005

or normal BUN

Medical Treatment ***FLUID RESTRICTION

Stop drugs causing issue LIMIT TO 1000ML/24HRS

may be as little as 500-600ml/24hrs IF CHF -- Lasix (temporary fix)

What do watch for? Treat underlying problem

Chemo, radiation demeclocycline (Declomycin) & Lithium

600 po-1200mg/day to inhibit ADH

Nursing Interventions-SIADH

Fluid restriction Daily weights 1 lb. weight = 500ml fluid retention Accurate I & Os

Nursing Management-SIADH

F & E imbalances fluid intake

High risk for injury r/t complications of fluid overload (seizures)

Posterior HYPOpituitaryADH Disorders

Diabetes Insipidus

(too little ADH)

Etiology of DI

50% idiopathic Central (aka. neurogenic)

usually occurs suddenly head trauma, brain tumors, infection

Nephrogenic inability of tubules to respond to ADH drug therapy, renal damage, heredity

Psychogenic what is this?

Clinical Manifestations-DI

Polydipsia Polyuria (10L in 24 hours) Severe fluid volume deficit

wt loss tachycardia constipation Shock

Diagnostic Tests-DI

or urine specific gravity

or serum Na

or serum osmolality

Diagnostic Tests - DI Water deprivation test

Urine output >4000ml/24hr ----- fluid restrict at start of test <4000ml/24hr ---- fluid restrict at midnight

Baseline weight, HR & BP Labs?

Hold fluids for 6hrs (usually 6am-12noon) Hourly urine monitoring for urine SG, osmolality & volume Draw sample for plasma osmolality when urine osmolality

increases <30mOsm/kg When plasma osmolaity is >288mOsm/kg, pt is deydrated ---

admin vasopressin 5 units of Vasopressin (ADH) Subq Obtain urine osmolality 30-60minutes after injection

Discontinue test if pt weight drops >2kg at any time

DI- Diagnostic TestsReading the Results – Water deprivation

After ADH administered: Normal or psychogenic

Urine osmolality normal

Central Urine osmolality increases

Nephrogenic Minimal to no response

What is this patient at risk for? Is this test done at home or an acute care facility.

Medical Management-DI

Identification of etiology, H & P Tx of underlying problem Central

IV fluids? DDAVP (oral, IV, nasal spray) Pitressin s.c. IM, nasal spray Chlorpropamide

Nephrogenic

Neprhogenic DI Treatment

Dietary restriction of Na < 3grams/day

Thiazide diurectics (HCTZ, diuril) Allows kidney to absorb more H20 in loop of

Henle & distal tubule Increases the amount of Na excreted in the urine

Indocin (NSAID) Increases renal response to ADH

Mechanism of action of the paradoxical effect of thiazide diuretics on NDI.

Magaldi A J Nephrol. Dial. Transplant. 2000;15:1903-1905

© European Renal Association-European Dialysis and Transplant Association

Nursing Management-DI

Assess for F & E imbalances High risk for sleep disturbances Increase po/IV fluids RF Injury (hypovolemic shock) Knowledge deficit High risk for ineffective coping