Endocrine system Flashcards
Endocrine system - Anatomy
Regulation of blood calcium
Hypothalamus & Pituitary Glands
Hormones secreted by anterior pituitary (adenohypophysis)
- TSH (thyroid stimulating hormone) - thyroid
- ACTH (adrenocorticotropic hormone) - adrenal cortex
- GH (growth hormone) - bones + tissues
- Gonodotropic hormones - LH + FSH
- Prolactin - mammary glands
Hormones secreted by adrenal cortex
- Glucocorticoids - Cortisol
- Mineralocorticoids - Aldosterone
- Androgens - Testosterone
Acromegaly (adulthood) - cause, S/s
due to GH secreting tumor
- Enlargement of hands + feet
- Elongation of jaw bone
- Enlargement of visceral organs - hepatomegaly , cardiomegaly
- Hyperglycemia - GH blocks action og insulin
Prolactin secreting tumors - S/s
- Galactorrhea
- Hypogonadism
- Impotence
- Amenorrhea
Excess ACTH - S/s
- Cushing’s syndrome
- Weight gain + HTN
- Masculinization (facial hair, deep voice) , amenorrhea
Hypophysectomy - monitor !
surgical removal of the hypophysis (pituitary gland) - transphenoidal approach
! Electrolytes - DI ? SIADH ? ; I+O; Dont band head below waist for 2 weeks; oral hygiene - no toothbrush, warm saline rinses ; humidified O2 (mouth breathers)
Parlodel (bromocriptine mesylate)
Dopamine receptor agonist
TX: prolactin or GH secreting tumors; Parkinson disease
NC: PO, take with food ( GI upset - nausea + constipation (Fiber 25g))
SE: Postural hypotension - get up slowly ;Orthostatic BP
- **BP drops 20 - HR increase 20 **
Sandostatin ( octreotide)
Somatostatin analogs
TX: inhibits GH secretion; used pre-op to shrink the GH secreting tumor
NC: must be given parenterally - subcut, IV or IM
SE: **Decreased GI and gallbladder motility ** - gallbladder disease - bile duct stones + gallstones
Hormones secreted by Hypothalamus and stored + released by the Posterior pituitary gland
- Oxytocin - ejection of milk
- ADH - stimulates reabsorption of water by the kidneys ; vasoconstrictor
Diabetes Insipidus (DI) - S/s
Decrease in ADH
Polyuria - dehydration - increased serum osmolarity - polydipsia ; urine is dilute - low specific gravity
Hypernatremia
Hypernatremia - S/S
_135-145 _
- Thirst - craving cold water
- Sticky mucus membranes
- Increased T + HR
- Weak, irritable
- Mental confusion
Fluid Deprivation Test
DX of DI
Pt. has no fluids - monitor Q1 - weight, urine output, Na level.
Dehydration triggers kidneys to concentrate urine
Stop :
- Severe hypernatremia
- Loose more than 3-5 % of body weight
- Hypovolemia - shock
DI - TX
- Vasopressin - strong vasoconstrictive !!!! - CAD, PVD, Raynaud’s
- DDAVP - Desmopressin acetate - synthetic without strong vasoconstr. properties - IV, nasal spray, PO
SIADH - S/S
Increase in ADH
Water retention - decreased serum osmolarity - dilutional Hyponatremia - Oliguria - increased urine osmolarity and sp. gravity
SIADH - TX
- Na = or > 125 - Fluid restriction - to balance Na and H2O - explain to pt. and family
- Na< 125 - S/s of hyponatremia develope -
3% Hypertonic Saline - small amount, slowly ( 12 in 24 hrs increase)
!!! Cerebral edema
- Demectocycline (Declomycin) - antibiotic - off label use - inhibits ADH secretion
Cushing’s disease - causes
adrenal or pituitary tumors; steroids (Prednisone)
Increase in glucocorticoids (Cortisol)
Cushings - S/s
- Truncal obesity (alteration in fat metabolism)
- Moon face
- Buffalo hump
- Thin arms + legs (increase breakdown of protein )
- Thin skin - increase fragility of capillaries - bleeding
- Generalized weakness + lethargy
- GI distress - increase acid
- Risk for infection - poor healing
Cushings - labs
- Hyperglycemia - monitor sugar; tx: insulin
- Hypokalemia - retaining Na + H2O - increase in aldosterone - HTN - I+O, weights
- Hypocalcemia - osteoporosis
Cushings - DX
- H+P
- Dexamethasone (Decadron) suppression test - give lil dose PO (11pm) - to see if adrenal glnad shuts off; if doesnt - tumor - adrenal? pituitary?
- 24 hour urine (free cortisol levels) - waste first; signs everywhere ; lab for instructions - ice? preservatives?
Cushings - TX
- Pituitary ? - Hypophysectomy
- Adrenal ? - Adrenalectomy
- reduce/discontinue exogenous steroids
- Na restriction, low carbs diet
Increase Ca + vit D , protein and ambulation
Fluid restrictions
Emotional support
Addisonian Crises
Causes - both adrenal glands removed , abruptly stopped taking steroids (due to nausea?)
Life threatening event !!!
Decrease in Na and BP
Increase in K - tx: insulin drip (push K into the cell); Kayexalate (NG, PO, enema) and HR
TX: IV steroids replacement
Fluid replacement
Hypoglycemia - D5W, D10W, Glucagon
Addisons - S/s
Decrease in mineral (aldosterone) and glucocorticoids (cortisol)
- Lethargic, weakness
- Hypoglycemia - sweating, confusion, shakiness, tremors
- Postural hypotension
- Weight loss - due to GI disturbances
- Bronze pigmentation of skin
- Mental instability - severe psychosis
Addisons - TX
Lifelong hormone replacement therapy (Pt. and family teaching )
- Cortisone , Hydrocortisone, Prednisone - in the am with breakfast - decrease GI upset - replace glucocorticoids
- Florinef (fludrocortisone) - replace mineralocorticoids
Wear med. alert bracelet
Primary Aldosteronism
Increase in aldosterone
- Na + H2O retention
- Decrease in K + hydrogen ions - metabolic alkalosis
DX: Abnormal electrolytes
Renin (decrease) - aldosterone (increase) stimulation test
TX: correct electrolytes imbalances ; Adrenalectomy (abdom. insicion) if hyperplasia or tumor of adrenal gland
Pheochromocytoma
adrenal medulla disorder - tumor
Increase in catecholamines - epinephrine + norepinephrine
Pheochromocytoma - S/s - 5 Hs
- Headache - vasoconstriction
- Hypertension - severe - stroke ! - Hypertensive crisis
- Hyperhidrosis - excessive sweating
- Hyperglycemia - liver starts converting glycogen to glucose
- Hypermetabolism
** Tachycardia
Vanillylmandelic acid (VMA) - 24 hour urine test
DX of Pheochromocytoma
by-product of cathecholamine metabolism
+ CT and MRI of adrenal gland
Pheochromocytoma - NC
- Avoid stimulants - coffee, chocolate
- Do not palpate the abdomen - prevent tumor stimulation
- Pre-op - TX BP+ HR - Regitin
Regitin
alpha-adrenergic blocker; tx of HTN (phenochromocytoma); also tx of extravasation of vasoconstrictive meds (e: dopamine) to vasodilate the area
Hypertensive crisis - TX
- Nipride - vasodilator (smooth muscle relaxant) - IV drip - immediate reduction of BP - _Monitor BP - A-line _
- CCB
Hormones secreted by thyroid gland
- T3 - triiodothyronine - 20% more potent
- T4 - thyroxine - 80 %
- Calcitonin - decrease blood calcium levels - buildup of bone
Hyperthyroidism - S/s
- Nervous + irritable
- Palpitations, chest pain - increased metabolism - increased catecholamines
- Flushed skin
- heat intolerance
- Weight loss
- Goiter
- Bulging eyes - Exophthalmos - fatty deposits behind eyes - Graves disease (autoimmune)- artificial tears, patch eyes (at night)
Hyperthyroidism - DX
- Labs - Increase in TSH
- Thrill + bruit over thyroid gland -palpate
- Radioactive iodine 123 (short acting, no precautions) thyroid scan
- Ultrasonography + EKG
Hyperthyroidism - TX - Radioactive iodine 131
Long acting; Goal - destroy part of the thyroid gland - get pt. into euthyroid state (normal)
SE: Hypothyroidism
Radiation precautions 2 weeks - 1mo (avoid children, pregnant women)
Avoid products with iodine - multivitamins, cough syrup, table salt
- Propylthiouracil (PTU)
- Tapazole (Methimazole)
Antithyroid medications - black box warning
- SE: liver failure
- SE: birth defects
Takes time to work - 3-4 weeks for improvement
Lugol’s solution
SSKI
Iodine solutions - TX of hyperthyroidism
Pt. drinks - mix with milk or water; use straw; - decreases amount of T3 + T4
Can be used pre-op to shrink thyroid gland - reduce vascularity ( decrease blood flow )
Thyroidectomy - subtotal or total (cancer)- post op NC
- Support neck
- Assess voice - laryngeal nerve damage ? - speak
- Airway !!! - edema ? bleeding ?
- Stridor - emergency - blocked airway
- Vitals, trach tray at bedside
- Check dressing (look behind) ; JP
Thyroid Storm or Crises - S/s
due to uncontrolled hyperthyroidism (Grave’s disease) - often triggered by stressor ( trauma, infection, post-op)
- Tachycardia
- Hypertension - tx: beta-blockers
- Fever - even 1 degree increase - report
Thyroid storm - TX
- Cooling blankets; ice packs; Tylenol ( No Aspirin !!!)
- O2
- Fluid, glucose, antithyroid meds - Propylthiouracil + Tapazole
Hypocalcemia - S/s
Ca 9-10.5
due to hypoparathyroid; parathyroid gland can be removed during thyroidectomy
- Numbness + tingling - fingers, toes, around mouth
- Chvostek’s (facial nerve twitching) + Troussea’s signs (carpopedal spasm)
- Laryngeal spasm + hyperreflexia
* Watch for tetany
Hypocalcemia - TX
- Calcium gluconate IV - mix with D5W not NS
- Phosphate binding meds - Phoslo ( calcium acetate); Dialume (aluminum hydroxide); Renagel
- Diet high in Ca + Vit D; low in P - milk + dairy products high in both
Hypoparathyroid - S/s
- Decrease in PTH
- Hypocalcemia
Hyperparathyroid - S/s
- Increase in PTH
- Hypercalcemia - decrease in excitability of NS - hypoactive
- brittle bones
- kidney stones (55%)
- muscle weakness
- fatigue and mental confusion
- over time - stenosis
Hyperparathyroid - DX
PTH levels
Increase in Ca levels
Decrease in P levels
X-rays of bones
Hyperparathyroid - Parathyroidectomy
remove 2-3 out of 4 glands to get pt in normal state
- Hydration !!! 2L/day - helps flush kidneys, prevent formation of kidney stones
- Loop diuretics - help toexcrete Ca
- Ambulation, exercise to strengten the bone
- Oral or IV Phosphate
- Diet low in Ca
- Calcitonin - pushes Ca back into the bone - High allergic reaction !!!
Hypothyroidism - S/s
Screening @ age 35 (every 5 years after)
- Extreme fatigue
- Hair loss
- Dry skin, brittle nails
- Cold intolerence
- Facial + Eyelid edema - deposits of mucus
- Bradycardia
- Weight gain
- Flat affect, slow mental process
Myxedema
severe hypothyroidism - can lead to coma - thickening + swelling of the skin
Synthroid
Levothyroid
synthetic thyroid replacement - life long ;
Takes time to work - 3-4 weeks
Admin. in am on an empty stomach ; same time each day; full glass of water
Monitor labs - start on low dose - increased metab. - increase demand for O2
Hypothyroidism - labs
Increase in TSH
Decrease in T3 + T4
