ATI Unit 12 Hypothyroidism Flashcards
what is hypothyroidism
decreased amount of circulating hormones (remember T3 = triiodothyronine; T4 = thyroxine), causing decrease in overall metabolic activities
classifications of hypothyroidism
mechanism
1. primary: most common; either autoimmune disease (Hashimoto’s disease) or loss of thyroid gland (radioactive iodine therapy; iodine depletement in diet; thyroidectomy)
- secondary: failure of anterior pituitary (secretion or response) eg pituitary tumors
- tertiary: problem with hypothalamus releasing thyroid-releasing factor (TRF)
also….
age of onset
1. Cretinism: hypothyroidism in infants; inhibits skeletomuscular growth and CNS = cognitive retardation, inhibited growth or both
2. juvenile hypothyroidism: usually autoimmune thyroiditis; same treatment as adult
3. adult hypothyroidism
most at risk group for hypothyroidism
30-60 yo women using meds lithium (Lithobid) or amiodarone (Cordaronel) with inadequate intake of iodine
what are the manifestations of hypothyroidism?
Early Can't go in because the weight slows, very cold Can't go - lethargy, fatigue - depression - joint/muscle pain
Because the weight slows
- constipation
- weight gain with no increase in calorie intake
Very cold
- intolerance to cold
- pale skin
- hair loss
- brittle fingernails
Late findings Slow down, it won't go down Slow down - braydcardia, hypotension, dysrhythmias - slow thought process/speech (raspy voice) - hypoventilation., pleural effusion - decrease taste/smell - amenorrhea/menorrhagia - decreased libido
It won’t go down
- mucousal, non-pitting edema in face, hands, feet (myxedema)
- thickening of skin (dry, flaky sin)
remember: thinning of hair on eyebrows
Important lab findings for hypotyroidism
- T3 and T4 decreased
- CBC = anemia
- Ok so for TSH
primary: think the thyroid isn’t secreting or maybe not there so hypothalamus/pituitary picking up that there isn’t enough T3/T4, so it releases more to compensate but thyroid doesn’t respond properly
so primary = increased TSH
secondary: malfunction with pituitary gland so TSH never get released
so secondary = decreased TSH
if you use a radioisotope scan/uptake (remember radioisotope = 123I), what would happen
- clients with hypothyroidism have low uptake of iodine preparations
Nursing implications for hypothyroidism
- Remember to monitor BP, RR, HR b/c all of these are lowered. Put on anti-emboli stockings to promote venous return/prevent clots.
- Give low-calorie, high bulk diet and laxatives to relieve constipation. Promote activity with lots of rest periods for this reason and to promote oxygenation.
(remember AVOID FIBER LAXATIVES b/c they mess with levothyroxine absorption) - Clothing layers, room temp higher, warm liquids but avoid electric blankets b/c of desensitivity of patient to feeling burns
what meds are highly cautioned in patients with hypothyroidism?
CNS depressant like barbs or sedatives (Resp depression)
Medications for hypothyroidism
- Thyroid hormone replacement therapy = levothyroxine (Synthroid)
- increases effects of warfarin (Coumadin) and can increase need for insuling and digoxin (Lanoxin)
- meds that decrease absorption of levothyroxine = cimetidine (Tagament); lansoprazole (Prevacid); and colestipol (Colestid)
- causes increased oxygen demand on heart so titrate up (so nurse needs to monitor for angina, palpitations, rapid heart rate, SoB)
- take med 1-2 hrs before breakfast
- NO fiber supplements (calcium, iron, antacids)
- monitor for hyperthyroidism (tremors, tachycardia, heat intolerance, palpitations, rapid weight loss)
- lifelong therapy
what is myxedema
- non-pitting, mucousal edema of face/extremities that is life-threatening when hypothyroidism is untreated, a stressor like infection or stroke hits someone with hypothyroidism, or if levothyroxine is suddenly stopped
Manifestations (Think SLOW again)
- resp depression (hypoxia, hypercapnia)
- decreased cardiac output
- leathargy, stupor, coma
- hypothermia
- bradycardia/hypotension
- hyponatremia
Nurse
- ABCs, warmth
- administer large IV bolus doses of levothyroxine (Synthroid)
- treat hypoglycemia with glucose
- administer corticosteroids
