Hyperthyroidism

 Hyperthyroidism
A sustained increase in synthesis and release of thyroid hormones by thyroid gland

Occurs in 2% of women and 0.2% in men

Highest frequency 30-50 year olds

Common form is Graves’ disease

Other causes
Thyroiditis
Nodular goiter
Exogenous iodine excess
Pituitary tumors
Thyroid cancer


Thyrotoxicosis refers to physiologic effects of hypermetabolism resulting from circulating levels of T3 and T4

Hyperthyroidism and thyrotoxicosis occur together as Graves' disease
Etiology and Pathophysiology
Graves' disease

Autoimmune disease of unknown etiology

Diffuse thyroid enlargement and excessive thyroid hormone secretion

Etiology and Pathophysiology
Precipitating factors

Insufficient iodine supply

Infections

Stressful life events interacting with genetic factors


Etiology and Pathophysiology
Graves’ disease accounts for 75% of cases

Antibodies are developed to the TSH receptor

May progress to destruction of thyroid tissue
Etiology and Pathophysiology
Toxic nodular goiters
Thyroid hormone-secreting nodules independent of TSH
Begin as follicular adenomas
Small autonomous nodules do not secrete enough to cause clinical thyrotoxicosis, but large nodules may
Clinical Manifestations
Increased number of -adrenergic receptors
Goiters
Bruits
Ophthalmopathy
Clinical Manifestations
Exophthalmos
Impaired drainage from orbit, increasing fat and edema in retroorbital tissues

Eyeballs forced outward and protrude

Corneal surfaces become dry and irritated

Clinical Manifestations
Cardiovascular system
Systolic hypertension
Increased CO
Arrhythmias
Cardiac hypertrophy
Atrial fibrillation

Clinical Manifestations
GI system
Increased appetite, thirst
Weight loss
Diarrhea
Splenomegaly
Hepatomegaly

Clinical Manifestations
Integumentary system
Warm, smooth, moist skin
Thin, brittle nails
Hair loss
Clubbing of fingers
Diaphoresis
Vitiligo
Clinical Manifestations
Musculoskeletal system
Fatigue
Muscle weakness
Proximal muscle wasting
Dependent edema
Osteoporosis


Clinical Manifestations
Nervous system
Fine tremors
Insomnia
Lability of mood, delirium
Hyperreflexia of tendon reflexes
Inability to concentrate
Clinical Manifestations
Reproductive system
Menstrual irregularities
Amenorrhea
Decreased libido
Impotence
Gynecomastia in men
Decreased fertility
Other Clinical Manifestations
Intolerance to heat

Increased sensitivity to stimulant drugs

Elevated basal temperature

ComplicationsThyrotoxic crisis
Acute, rare condition where all manifestations are heightened
Life-threatening emergency/death rare when treatment initiated
Presumed causes are additional stressors
ComplicationsThyrotoxic crisis 
Manifestations include
Restlessness
Agitation
Seizures
Abdominal pain
N/V/D
Coma
ComplicationsThyrotoxic crisis 
Treatment and therapy

Reduce thyroid hormone levels and clinical manifestations

Therapy aimed at fever reduction, fluid replacement, and management of stressors
Diagnostic Studies
Laboratory findings for TSH and free thyroxine

Radioactive iodine uptake is indicated to differentiate Graves' disease from other forms of thyroiditis
Collaborative Care
Drug Therapy
Antithyroid drugs PTU and Tapazole
Inhibit synthesis of thyroid hormones
Improvement begins in 1-2 weeks
Continued 6 months to 2 years
Not curative
Collaborative Care
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
Collaborative Care
Iodine
Decreases vascularity of thyroid gland

Maximal effect seen within 1-2 weeks

Long-term iodine therapy is not effective
Collaborative Care
-adrenergic blockers
Symptomatic relief of thyrotoxicosis resulting from -adrenergic receptor stimulation

Propranolol (Inderal) administered with other antithyroid agents

Collaborative Care
Radioactive Iodine Therapy (RAI)

Damages or destroys thyroid tissue

Delayed response 2 to 3 months

Treated with antithyroid drugs and Inderal before and during first 3 months of RAI
Collaborative Care
Radioactive Iodine Therapy (RAI)
High incidence of posttreatment hypothyroidism

Need for lifelong thyroid hormone replacement
Collaborative Care
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
Collaborative Care
Surgical Therapy
Indicated for those
unresponsive to drug therapy
with large goiters causing tracheal compression
with possible malignancy

Collaborative Care
Surgical Therapy
Endoscopic thyroidectomy appropriate with small nodules with no malignancy
Less scarring, pain, and recovery time




Collaborative Care
Nutritional Therapy
High-calorie may be ordered for hunger and prevention of tissue breakdown
Protein allowance 1 to 2 g/kg ideal body weight
Avoid caffeine, highly seasoned foods, and high-fiber foods
Nursing ManagementNursing Assessment
Health History
Preexisting goiter
Recent infection or trauma
Immigration from iodine-deficient area
Medications
Family history of thyroid or autoimmune disorders
Nursing ManagementNursing Assessment
Weight loss
Nausea
Diarrhea
Dyspnea on exertion
Muscle weakness
Insomnia
Heat intolerance
Nursing ManagementNursing Assessment
Decreased libido
Impotence
Amenorrhea
Irritability
Personality changes
Delirium


Nursing ManagementNursing Assessment
Objective Data
Agitation
Hyperthermia
Enlarged or nodular thyroid gland
Eyelid retraction
Diaphoretic skin

Nursing ManagementNursing Assessment
Brittle nails
Edema
Tachypnea
Tachycardia
Hepatosplenomegaly

Nursing ManagementNursing Assessment
Hyperreflexia
Fine tremors
Muscle wasting
Coma
Menstrual irregularities
Infertility
Nursing ManagementNursing Diagnoses
Activity intolerance

Risk for injury

Imbalanced nutrition: less than body requirements

Anxiety
Nursing ManagementNursing Implementation
Acute thyrotoxicosis
Administer medications

Monitoring cardiac arrhythmias

Ensuring adequate oxygenation and IV fluids
Nursing ManagementNursing Implementation
Light bed coverings if diaphoretic

Encourage and assist with exercise

Restrict visitors

Establish supportive relationship
 Nursing ManagementNursing Implementation 
Apply artificial tears to relieve eye discomfort

Elevate HOB, and salt restriction for edema

Tape eyelids shut for sleep if they cannot close
Nursing ManagementNursing Implementation
Thyroid surgery
Assess for signs of iodine toxicity
Teach C&DB and leg exercises
Suction equipment, tracheostomy tray available in room
Calcium salts available for tetany
Nursing ManagementNursing Implementation
Postoperative:
Assess for signs of hemorrhage or tracheal compression

Semi-Fowler’s position and support head with pillows
Nursing ManagementNursing Implementation
Postoperative:
Monitor vital signs
Check for signs of tetany
Trousseau’s sign and Chvostek’s sign should be monitored
Administer pain medications

Nursing ManagementNursing Implementation
Ambulatory and Home Care
Monitor hormone balance periodically

Reduce caloric intake to prevent weight gain

Avoid goitrogens
Nursing ManagementNursing Implementation
Adequate iodine is necessary for thyroid function, but excess inhibits the thyroid
Exercise helps stimulate thyroid
Avoid high environmental temperatures, as they inhibit regeneration

Nursing ManagementNursing Implementation
Radioactive iodine therapy
May cause dryness and irritation of mouth and throat

Teach symptoms of hypothyroidism
Nursing ManagementEvaluation
Relief of symptoms

No serious complications related to disease or treatment

Cooperate with therapeutic plan
Thyroid Enlargement
Goiter is hypertrophy of thyroid gland caused by excessive TSH stimulation
Thyroid Enlargement Etiology and Pathophysiology
Can also be caused by growth stimulating immunoglobulins

Goitrogens cause goiters only in iodine-deficient areas

Thyroid Enlargement Etiology and Pathophysiology
TSH and T4 levels are measured to determine if goiter is associated with hypothyroidism, or normal thyroid function

Thyroid antibodies measured to assess for thyroiditis