Download Endocrine Disorders Thyroid Gland

Endocrine Disorders
Thyroid Gland
Jane E. Binetti DNP MSN RN
Thyroid Gland
• In the neck, anterior to the trachea
• Extremely vascular
• Regulated by:
▫ TSH
• Produces and secretes
▫ T4 (thyroxine)
▫ T3 (triiodothyronine)
▫ Calcitonin
What about Thyroid Gland
• Thyroid disorders are the most common of all
endocrine issues
• Thyroid hormones regulate
▫ Metabolism
▫ Growth and development
• Disorders of the thyroid
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Goiter
Nodules
Thyroiditis
Hyper/hypo
Goiter
• Large thyroid gland
• Gland is stimulated to grow
▫ Can lead to hyperthyroidism or hypothyroidism
▫ Worldwide, most often due to lack of iodine
• In US caused by:
▫ Nodules, or over/under production of hormone
▫ Goitrogens are thyroid inhibiting substances
 Broccoli, cabbage, kale, cauliflower, mustard,
peanuts
 Lithium, amiodorone, salicylates, sulfonamides
More on Goiters
• Non toxic Goiters
▫ Enlargement not from inflammation or cancer
▫ Pt has normal thyroid levels
• Nodular Goiter
▫ Secrete thyroid hormone without TSH stimulation
▫ Usually benign adenoma
• Toxic Nodular Goiter
▫ Toxic because they cause hyperthyroidism
▫ Most frequent after 40
▫ Common in Grave’s Disease
Thyroiditis
• Inflammation of thyroid that can cause a goiter
• Types
▫ Subacute - viral infections
▫ Acute - bacteria and fungus
▫ Hashimoto’s is autoimmune; tissue is destroyed
by antibodies
▫ Silent painless goiter occurs within 6 mo post
partum
 Autoimmune reaction to fetal cells in the mom’s
thyroid ? Early Hashimoto’s?
Thyroiditis Treatment
• Acute or subacute may resolve in weeks or
months with no treatment
• Antibiotics as necessary for bacterial, even
drainage
• NSAIDS or steroids for inflammation
• Propranolol (Inderal) or atenolol (Tenormin) for
cardiac sx
• Thyroid hormone for resulting hypothyroidism
• Teach compliance with treatment
Hyperthyroidism
• Over secretion of thyroid hormones
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Seen more in women than men
20-40 years old
Most common form is Grave’s disease
Other causes: thyroiditis, toxic nodular goiter,
excess iodine intake, pituitary tumors, thyroid CA
▫ Thyrotoxicosis is acute, severe hyperthyroidism
Grave’s Disease
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75 - 80% of hyperthyroidism cases
Autoimmune
Diffuse large thyroid gland
Antibodies attach to TSH receptors, cause over
secretion of T3 and T4
• Can remit and exacerbate without tx
• Precipitating risk:
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iodine, infection, stress, genetic factors, smoking
• Can cause thyrotoxicosis
• Can degrade the thyroid, lead to hypothyroidism
What do you see?
• Excess thyroid hormone causes:
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Large gland – goiter
Bruit in the gland
Exophthalmos
Tachycardia, bounding pulse
Nervousness, irritability, tremors
Flushed skin, heat intolerance
Diarrhea, weight loss
Fatigue, muscle weakness, edema, osteoporosis
Exophthalmos
Diagnostics
• Thyroid studies
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TSH – most accurate test of thyroid function
Total T4, Free T4
Total T3, Free T3
Thyroid antibodies
Thyroid scans, ultrasound
Biopsies
Diagnostics
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TSH levels will be decreased
Free T4 levels increased
Total T3 and T4 not definitive
RAIU – Radioactive Iodine Uptake
▫ Used to differentiate Grave’s from thyroiditis
▫ Grave’s uptake = 35% - 95%
▫ Thyroiditis = < 2%
Complications
• Thyrotoxicosis (Thyroid Storm)
▫ Life threatening, rare
▫ Abrupt onset -sudden release of thyroid hormones
▫ Precipitated by stress, thyroidectomy, trauma or
an acute infection
• Symptoms
▫ Extreme fever, tachycardia
▫ Tremors, Seizures
▫ Loss of mental acuity -> Delirium Stupor ->
Coma
Collaborative Care
• Goal is to stop the effects of overproduction
▫ Anti-thyroid medications
▫ Radioactive Iodine therapy
▫ Subtotal or total thyroidectomy
• Choice of therapy depends on
▫ Patient age
▫ Severity of disease
▫ Complicating situations
More on therapies
• Anti-thyroid drugs:
▫ PTU – (propylthiouracil)
 Inhibits synthesis of thyroid hormones
 Blocks peripheral conversion of T4 to T3
▫ Tapazole (methimazole)
 Improvement in 1-2 weeks, better in 4-8
• 20-40% have spontaneous remission (6-15mo)
• Noncompliance is a big issue
• Used for Grave’s, in pregnancy, and need for
euthyroid before surgery or radiation
Anti-Thyroid meds continued
• Iodine
▫ Used with other drugs for thyroidectomy prep or
thyrotoxic crisis
▫ Inhibits synthesis of T3 and T4 and blocks release
▫ Decreases vascularity in gland
▫ Max effect in 1-2 weeks
▫ Reduced effect long term
▫ SSKI and Lugol’s solution
Beta Adrenergic Blockers
• Symptomatic relief of thyrotoxicosis
• Block sympathetic nervous stimulation
• Excess thyroid hormone stimulates B adrenergic
receptors
• Beta Adrenergics used in conjunction with anti
thyroids
▫ Propranolol (Inderal)
▫ Atenolol (Tenormin) for asthmatics and cardiacs
Radioactive Iodine Therapy
• Treatment of choice in non-pregnant adults
• Damages or destroys all thyroid tissue to control
secretion of hormones
▫ High incidence of post treatment hypothyroidism
• Delayed response requires anti-thyroid drugs
and beta adrenergics initially
• Radioactivity is low, so done outpatient
• Pt Education important!!!
Surgical Therapy
• Thyroidectomy
▫ Large goiters with compression
▫ Non responsive to medical tx
▫ Cancer
• Subtotal
▫ Removes most of gland but not all
• Endoscopic
▫ Small incisions to take some gland, or nodes
• Prior to surgery meds can make pt euthyroid
Post op complications
• Hypothyroidism
• Damage or removal of parathyroid glands
▫ Causes hypoparathyroidism and hypocalcemia
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Hemorrhage
Injury to recurrent laryngeal nerve
Thyrotoxic crisis
Infection
Nutritional Therapy
• Hyperthyroid state
▫ Hypermetabolic state needs increased caloric
intake
▫ Satisfy hunger, prevent catabolic state
▫ High protein, high carbs
▫ Avoid highly seasoned, high fiber foods
▫ No caffeine
What do you do?
• Hyperthyroidism is treated as outpatient
• Acute thyrotoxicosis are admitted to ICU
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Assess your patient!
Meds ordered to block thyroid hormone production
O2, IVs, watch electrolytes, EKGs
Calm, quiet, cool environment
Emotional support
Eye protection, elevate HOB, skin care
Dietary support
Pt education
Post -op
• Assess your patient!!
• Semi-Fowlers, post op VS
• Laryngeal nerve irritation or damage can lead to
spasm and stridor
▫ Can be related to tetany – damage to parathyroids and
hypocalcemia
▫ Watch for signs of hypoparthyroidism
 Assess tingling of extremities and mouth
▫ Chvostek’s and Trousseau’s
• Watch bleeding – neck swelling and behind the neck
• Hoarse for 3-4 days
• Post op pain meds
Hypothyroidism
• Undersecretion of thyroid hormones
▫ One of most common medical disorders in US
 1 in 50 women; 1 in 300 men
▫ Primary from destruction of thyroid or defective
synthesis
▫ Secondary from pituitary or hypothalamic disease or
dysfunction
▫ Radiation exposure to the neck, family history, women
>50 and post-partal
• Transient causes:
▫ Thyroiditis
▫ Non-compliance
Primary Hypothyroidism
• Worldwide caused by lack of iodine in diet
• In US most common cause is atrophy of gland
▫ Hashimoto’s thyroiditis
▫ Grave’s disease for long time
▫ Treatment of hyperthyroidism causes hypothyroidism
 Surgical removal
 RAI
▫ Drugs
 Amiodorone (Cordarone) – has iodine
 Lithium blocks hormone release
▫ Develops in infancy - cretinism
What do you see?
• Deficiency causes:
▫ Capillary fragility, varied BP, cardiac hypertrophy,
anemia, angina, MI
▫ Dyspnea
▫ Decreased appetite, N/V, constipation, wt gain,
scaly tongue
▫ Brittle nails, poor turgor, puffy face, pallor,
decreased sweating
Diagnostics
• TSH and free T4 are most often used in
conjunction with physical exam
• TSH helps determine cause
▫ High TSH = defect in the gland
▫ Low TSH = defect in the hypothalamus or pituitary
• After TRH stimulation
▫ Hi TSH = hypothalamus issues
▫ No change = anterior pituitary
• TPO AB means cause is autoimmune
Complications
• Myxedema Coma
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Progressive or sudden onset
Usually severe long term hypothyroidism
Medical Emergency
Precipitated by:
 Infection, medications, exposure to cold, or trauma
• Symptoms
▫ Subnormal temp
▫ Hypotension
▫ Hypoventilation
• Tx: IV thyroid hormone replacement, VS support
Collaborative/Nursing Care
• Euthyroid is the goal
▫ Synthroid – levothyroxine
 Adjusted to pt response and labs
 Cardiac pts have reduced dose
 Daily dose taken regularly
▫ Liotrix – 4:1 T4:T3; for pts acutely ill, faster onset
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Low calorie diet to aid weight loss
Mechanical cardiac /respiratory support prn
Assess VS, I/O, wt, mental status
Pt education – compliance!