Endocrine: Thyroid and Parathyroid Problems

TSH

from ant pituitary stimulates release of T3, T4

Calcitonin

hormone made by C cells in thyroid

•Secreted in response to high Ca

calcitonin lowers serum calcium by

§Inhibits transfer from bone to blood

§Increases storage of Ca

§Increases renal excretion

goiter

•Enlarged thyroid gland- treatment depends on cause

•May occur in either hypo- or hyperthyroidism

causes of goiter

iodine deficiency (most common cause worldwide)

•Soil & water iodine deficient

•Primary prevention – iodination of water

Other causes: Over or under production of thyroid hormone (most common in US)

•Thyroid enlarges to compensate for hormone deficiency

Treatment for goiters

•Overactive thyroid- Radioactive iodine

•Hypothyroid- replace thyroid hormone

•Surgery if goiter doesn’t resolve with medical management- partial or totally thyroidectomy

Goitrogens

foods or meds that inhibit T4 production

•Foods – cabbage, broccoli, peanuts, etc.

•Meds – glucocorticoids, lithium, phenytoin (anti seizure drug), etc.

Non-toxic goiters- enlarged but no disease associated

Toxic nodular goiter- usually associated with hyperthyroidism-Graves disease

Hyperthyroidism

•Graves’ disease – autoimmune disorder

•Can be associated with other autoimmune disorders

•Incidence >women than men (more common in women)

•Thyroid storm: thyroidtoxitosis

•20-40 years old

•Over secretion of thyroid hormone

•Excessive doses of thyroid medications

•Diagnostics: Low or undetectable TSH, Normal to Increased T3,  T4

Exophthalmos

•caused by fluid accumulates in fat pads & muscles behind eyes

•Eyes protrude

•Eyelids may not close completely

•Risk for corneal abrasions, vision changes/loss, diplopia

Exophthalmos tx

•artificial tears, eye patching at night, dark glasses may reduce glare

•If severe- corticosteroids, radiation and possibly surgery

diagnostics with graves diease

•TSH- decreased

•T3 and T4- elevated

•Ultrasound, ECG

•Thyroid scan- nuclear med test using radioisotope

•No scan if pregnant

complications with hyperthyroidism

heart disease - can lead to HF (signs: JVD, peripheral edema)

thyroid storm (thyrptoxicosis)

•Thyroid storm (Thyrotoxicosis)

complication of hyperthyroidism/graves disease

•Rare but dangerous

•High fever up to 106 F, tachycardia, dehydration, heart failure, N/V, change in LOC

•Triggered by physical stressors (Including pregnancy/delivery, trauma, surgery)

•Clinical diagnosis – no specific tests

•No aspirin!!!! –causes release of T4

Anti-thyroid meds

Goals: suppress over secretion of thyroid hormone and effects, prevent complications

•Methimazole (Tapazole)

•Propylthiouracil (PTU)

beta blockers

idione

Methimazole (Tapazole)

•Prevents thyroid gland from producing thyroid hormone

•Contraindicated in pregnancy and breastfeeding

•Alters therapeutic effect of some meds- ex. coumadin

Propylthiouracil (PTU)

•Impairs TH synthesis- blocks conversion of T4 to T3

•Results take several weeks, therapy 6-15 months

May cause dangerous drop in WBC

beta blockers to help hyperthyroidism

usually propranolol or metoprolol

Decreases tachycardia, nervousness, irritability, and tremors - used. to calm the body, not treat the sx

Iodine for hyperthyroidism

potassium iodine solution and Lugol’s solution used to shrink thyroid before surgery

•Increases TH storage, inhibits circulating amount

•10 days before thyroidectomy

Radioactive iodine Therapy

Mainly for middle-aged & older patients

NOT for pregnant women

destroys thyroid cells

•Given PO – as outpatient unless dose is very large (radiation precautions vary by dosage)

•s/s subside in 6-8 weeks

•Treatment- may cause dryness and irritation in mouth

Radiation exposure precautions at home

Private toilet, multiple flushes

Separate laundry at home

Avoid handling food for others at home

Disposable dishes  

Don’t share toothbrush

Increase distance and limit contact with pregnant women and small children for 7 days after therapy

Nutrition – hyperthyroid

Diet – high calorie 4000-5000 calorie to meet high metabolism needs

Protein 1-2 g/kg of ideal body weight

Avoid caffeine

Avoid high fiber diet d/t hyperactive GI tract

Other nursing considerations r/t restless, insomnia, elevated temp

Calm environment

Cool room, light bed linen

Coping- build trust

Monitor temp for increase

Monitor ECG for changes in heart rhythm

Thyroidectomy

Partial or total Thyroidectomy indicated for:

Goiter with tracheal compression

No response with meds

Thyroid cancer

If total thyroidectomy- require lifelong medication therapy (such as levothyroixine)

prep for thyroidectomy

Patient must be euthyroid

•Pre-op preparation can take 2-3 months

•Thyroid labs- normal levels

•High protein, high carb diet prior to surgery

•Cardiac status assessment- meds to control heart rate

post op care for thyroidectomy

•Maintain airway patency

Assess for edema, hemorrhage

Report signs of spasms, stridor, dyspnea, change in speech

Position semi-fowlers, support head and neck

•Pain control

•Infection

•Hypothyroid – need hormone replacement

what complication can happen wth a thyroidectomy pertaining to parathyroid

•Hypo-parathyroid – risk for hypocalcemia

•Monitor/treat hypocalcemia (normal Ca 9.0-10.5)

s/s of hypocalcemia

• Numbness/tingling (paresthesia)

  • Lips, fingers, toes

• Muscle cramps

• Classic signs (VERY testable):

  • Chvostek's sign
    → Tap cheek → facial twitch

  • Trousseau's sign
    → BP cuff inflation → hand spasms

Hypothyroidism

Deficiency of thyroid hormone (T3 & T4)

•Complication: Myxedema – severe hypothyroidism (rare but life threatening)

Slows metabolism, Lowers body temp, Decreased O2 consumption

Most R/T thyroid gland dysfunction

•Can also be from pituitary dysfunction (<TSH)

•Incidence >women than men

•30-60 years old

Etiology of hypothyroidism

•Primary –disfunction of thyroid gland

•Defective hormone synthesis

•Iodine deficiency

•Treatment for hyperthyroidism

•Autoimmune – Hashimoto’s disease

•Secondary –failure of Anterior pituitary decreases TSH production

clincial manifestations of hypothyrodism

hair loss, apathy, lethargy, dry ski,

intolerance to cold

receding hairline

facial and eyelid edema

extreme fatigue

thick tongue

anorexia

brittle nails and hair

hyperthyroidism clinical manifesttaions

intolerance to heat

finger clubbing

tachycardia

bulging eyes

high systolic BP

muscle wasting

tremors

diarreah

mestrua; changes

Diagnostics for hypothyroidism

•TSH elevated -problem is thyroid

•TSH low - problem pituitary

•T3 and T4 decreased

•Thyroid scan- low uptake of radioactive isotope

•ECG – sinus brady, dysrhythmias       

Hypothyroid Management

Hormone replacement – levothyroxine sodium (Synthroid)

Start with low dose in patients with heart disease, monitor for tachycardia, irregular rhythm

Must take med on empty stomach, 30-60 minutes before meals or 1-2 hrs after meal

•Avoid goitrogenic meds ex.  amiodarone, lithium, PTU

hypoThyroid meds may

•increase effects of anticoagulants

•decrease effects of digoxin

Hypothyroid Management

•Nutrition – focus on weight loss, achieve healthy weight

•Activity intolerance and fatigue

•Constipation

Complication: Myxedema Coma

•Medical emergency- Very rare but can be fatal

•Causes:  infection, trauma, cold, meds (opioids, sedatives, anesthesia, non-compliance with meds)

•Problems:

 Decreased metabolic rate

•Hypoventilation

•Hypothermia

•Cardiovascular -hypotension, bradycardia, dysrhythmia

•Hypoglycemia

Myxedema coma – life support

•Treat the problems- Ex., ventilatory support, IV fluids, warm blankets

•IV thyroxine (thyroid hormone), glucose, & corticosteroids

•Hyper-parathyroid

•Primary – increased circulating PTH – r/t tumor

•Secondary – compensation for low Ca levels, ex. Vit D deficiency or kidney disease

•Excess levels of PTH lead to hypercalcemia & hypophosphatemia (inverse relationship)

§Decreased bone density- risk for fx

Hypercalciuria – stones

•Hypo- parathyroid

•rare

•Low circulating PTH

•Iatrogenic – accidental removal or damage during head/neck sx

•Clinical manifestations d/t hypocalcemia- what are they?

• Numbness/tingling (paresthesia)

  • Lips, fingers, toes

• Muscle cramps

Classic signs (VERY testable):

• Chvostek's sign
  → Tap cheek → facial twitch

• Trousseau's sign
  → BP cuff inflation → hand spasms

Clinical manifestations d/t hypercalcemia

•Constipation, muscle weakness, fatigue

tx of. hyperparathyroid

•If not surgical candidate –

Treat hypercalcemia

Bisphosphonates- help inhibit osteoclast bone resorption

Fluids and diuretics if good kidney function

Surgical intervention- partial or complete

Post-op issues: Airway management, Hypocalcemia

tx of hypoparathyroid

•IV  Ca Gluconate

Monitor EKG during administration of Ca

Caution if patient on Digoxin- dysrhythmias

Assess IV site for phlebitis w/IV admin

•PO calcium supplements

•Vit D supplements- enhances intestinal absorption of calcium

•High Ca diet