Ch. 55 Flashcards
thyroid gland
- small butterfly shaped gland located in anterior neck
the thyroid gland secretes hormones that affect:
- body metabolism
- cellular regulation
- nutrition
- gas exchange
thyroid imbalances can lead to symptoms that can range from
mild to severe and life-threatening
thyroid gland surrounds the (anatomy)
- trachea
- larynx
palpating the thyroid gland
- hands on either side of the neck
- palpate with thumbs
thyroid hormones are
- T4 (thyroxine)
- T3 (triiodothyronine)
thyroid hormones regulate
regulates energy metabolism
growth and development
affects every body system (hypo or hyper)
hypothyroidism
reduced hormone secretion from the thyroid gland that results in decreased body metabolism
prevalence of hypothyroidism
- women ages 30-60
- women affected 7-10x more than men
hypothyroidism- most common cause
iodine deficiency is the most common cause
- most prevalent in iodine-deficient areas
hyperthyroidism is treated with
radio active iodine (RAI)
if the iodine intake is accurate, what is the primary cause of hypothyroidism?
the primary cause in the adult is an autoimmune problem resulting from a condition called Hashimoto’s thyroiditis
thyroid surgery
thyroidectomy: partial or total removal of the thyroid gland
hyperthryroidism
excessive thyroid hormone secretion from the thyroid gland that results in increased body metabolism
most common form of hyperthyroidism
Graves disease
prevalence of hyperthyroidism
- women, can occur at any age but most common ages 20-40
Graves Disease
autoimmune disorder of unknown etiology
- often occurs after episode of thyroid inflammation
pathophysiology of Graves Disease
- diffuse thyroid enlargement and excessive thyroid hormone secretion (T3&T4)
- antibodies are developed and attached to the TSH receptors on thyroid gland
- may progress to destruction of thyroid tissue
goiter
hypertrophy of thyroid gland caused by excessive TSH stimulation, usually visible and definitely palpable
Graves Disease Goiter
enlargement of thyroid gland, neck is very swollen
health history of patient with thyroid gland problems
- preexisting goiter
- recent infection or trauma
- immigration from iodine-deficient area
hyperthyroidism: clinical manifestations
Increased number of β-adrenergic receptors
Goiters
Bruits: abnormal blood flow (listen on carotids)
Ophthalmopathy (exophthalmos): protruding eyes
hyperthyroidism/grave’s: cardiovascular system effects
Systolic hypertension
Increased CO
Arrhythmias
Cardiac hypertrophy
Atrial fibrillation
hyperthyroidism/grave’s: integumentary system effects
Warm, smooth, moist skin
Thin, brittle nails
Hair loss
Clubbing of fingers
Diaphoresis
Vitiligo (loss of skin color in patches)
Eye balls protruding outward
hyperthyroidism/grave’s: nervous system effects
Fine tremors
Insomnia
Lability of mood, delirium
Hyperreflexia of tendon reflexes
Inability to concentrate
hyperthyroidism/grave’s: GI system effects
Increased appetite, thirst
Weight loss (r/t metabolism is sped up)
Diarrhea
Splenomegaly
Hepatomegaly
hyperthyroidism/grave’s: MS system effects
Fatigue
Muscle weakness
Proximal muscle wasting
Dependent edema
Osteoporosis
hyperthyroidism/grave’s: reproductive system effects
Menstrual irregularities
Amenorrhea: no period
Decreased libido
Impotence
Gynecomastia in men
Decreased fertility
thyrotoxic crisis (thyroid storm): sx
Acute, life-threatening
Hyperthermia
Severe tachycardia
Hypertension
Heart Failure
thyrotoxic crisis (thyroid storm): triggers
Trauma, infection, DKA, pregnancy
Vigorous palpation of the thyroid
thyrotoxic crisis (thyroid storm): diagnostic studies
Laboratory findings for TSH (low) and free thyroxine: T3&T4 (high)
TSH-RAb (Antibodies to TSH)
Radioactive iodine uptake
- Normal 5 to 35%
thyrotoxic crisis (thyroid storm): treatment
Symptom treatment
- racing HR: low dose beta blocker
- anxious: low dose anti-anxiety, sleeping pill
Antithyroid Medications
Iodine
thyrotoxic crisis (thyroid storm): treatment- antithyroid medications
Propylthiouracil (PTU)
Methimazole
- Inhibit synthesis of thyroid hormones
- 1-2 weeks to begin
- 4-8 weeks therapeutic
thyrotoxic crisis (thyroid storm): treatment- iodine
Useful with other antithyroid drugs in preparation for thyroidectomy or treatment of crisis
Large doses rapidly inhibit synthesis of T3 and T4 and block their release into circulation
Potassium iodine (SSKI) or Lugol’s solution (no iodine for pregnant women)
thyrotoxic crisis (thyroid storm): treatment- radioactive iodine
Damages or destroys thyroid tissue limiting hormone secretion
3 months to see effect
Usually causes hypothyroidism and requires life-long hormone replacement
thyrotoxic crisis (thyroid storm): surgical therapy
Subtotal thyroidectomy involves removal of significant portion of thyroid
- 90% removed to be effective
- If too much is removed, regeneration will not occur, results in hypothyroidism
Subtotal thyroidectomy post-op care
Assess for signs of hemorrhage or tracheal compression
Semi-Fowler’s position and support head with pillows
edema around the trachea
Monitor for signs/symptoms of Parathyroid involvement
thyrotoxic crisis (thyroid storm): nursing problems
- Activity intolerance: tired, fatigued
- Risk for injury: from being tired, muscle weakness
- Imbalanced nutrition: less than body requirements, eating but losing weight due to increased metabolism
- Anxiety: tremors
acute thryrotoxicosis: nursing care
Administer medications
Monitoring cardiac arrhythmias
Ensuring adequate oxygenation and IV fluids
Light bed coverings if diaphoretic
hypothyroidism s/sx: cardiovascular system
Increased capillary fragility
Decreased rate and force of contraction
Cardiac hypertrophy
Distant heart sounds
hypothyroidism s/sx: GI system
Decreased appetite
Nausea and vomiting
hypothyroidism s/sx: integumentary system
Dry, thick, elastic, cold skin
Thick, brittle nails
myxedema
sx of hypothyroidism
Accumulation of hydrophilic mucopolysaccharides in the dermis and other tissues
Causes puffiness
hypothyroidism diagnostic tests
- TSH (high)
- Thyroxine-T4 (low)
myxedema coma: manifestations
Mental sluggishness
Drowsiness
Lethargy progress gradually or suddenly to impairment of consciousness or coma
puffy eyes
myxedema coma: acute intervention
Monitor core temperature as patient is often hypothermic
Assess vitals, weight, I & O, and visible edema
myxedema coma: medication Levothyroxine
*aka synthroid
Monitor with CV patients
Report HR >100 (previously bradycardic, make sure that they do not become tachycardic)
Life-long therapy
Usually given before breakfast (empty stomach)
Thyroid preparations potentiate the effects of some common drug groups
- Antidepressants
- Digitalis compounds
- Anticoagulants
hypothyroidism: evaluation
think HR, RR, neuro evaluation
- Maintain normal cardiovascular function: BP & HR in normal range
- Maintain adequate respiratory function and gas exchange
- Demonstrate improvement in cognition: if there was an issue with cognition
hypothyroidism is most commonly caused by
iodine deficiency
- most prevalent in iodine-deficient areas
in places where iodine intake is adequate, the primary cause of hypothyroidism in adults is
atrophy of the gland
causes of hypothyroidism
- iodine deficiency* (#1)
- atrophy of the gland* (#2)
- autoimmune thyroid destruction
- infection of the thyroid tissue
- congenital absence or hypoplasia of thyroid tissues
- neck surgery
- irradiation, trauma
- wide variety of drugs
