Thyroid Storm/Thyroid Crisis, Hypothyroid, Hyperthyroid

Terms in this set (29)

What is thyroid storm/crisis
EXTREME sudden worsening of hyperthyroid symptoms brought on by stress, trauma, illness
-usually un/undertreated hyperthyroid
, over treated hypothyroid
-when pt stops taking Methimazole or PTU
Symptoms-thyroid storm/crisis
-high fever, tachycardia, arrythmias, vomiting, dehydration, coma, heat intolerance, sweating
Thyroid Storm characteristics
TSH level usually too low to detect
-T3, T4 are elevated and Free T3 & T4 may be very elevated
-CXR may show pulmonary edema
-pt develops hypotension, shock, followed by death
Tx-Thyroid Storm
Goal to decrease circulating thyroid hormone and support vital organ fx then look for cause
-Cooling blanket
-IV hydration
-PTU, then 1hr later Lugol's solution or alternatively methimazole-blocks production T4&T3
-Propranolol
-IV steroids to support circulation and help block production of T4&T3
-acetaminophen. DO NOT GIVE ASA or other salicylates, they can increase the level of circulating thyroid hormone
Hypothyroidism
-disease of thyroid (Primary)
-decifiency of TSH (secondary)
-Hypothalamic deficiency of TRH (Tertiary)
-Iodine deficiency
-Hashimoto's thyroiditis
-Damage to thyroid
-Idiopathic
-Iatrogenic
Hashimoto's Thyroiditis
-most common in middle-aged women
-adrenal insufficiency and type 1 diabetes
-may take months or year to be detected
-increased antibodies to thyroid peroxidase enzyme, causes inflammations in thyroid with eventual destruction of gland
Iodine deficiency
-before 1920's iodine deficiency was common (mostly Canada)
-intro to iodized salt eliminated "goiter belt"
Foods rich in Iodine
-cheese
-cows milk
-eggs
-ice cream
-Iodine-containing MV
-Iodized table salt
-Saltwater fish
-seaweed
-shellfish
-soy
-yogurt
Pituitary of Hypothalamic causes of hypothyroid
-tumors
-cysts
-stroke
-bleeding
-trauma
-surgery
-radiation
-infiltrative diseases
Euthyroid Sick Syndrome
-Chronic cardiac, renal and hepatic-have low T3, normal or low T4 and normal TSH
-Severe chronic diseases-stimulates the adrenal gland to produce excess cortisol in the bloodstream
-Cortisol inhibits peripheral conversion of T4 to T3 and promotes conversion of T4 into isomer of T3 called reverse T3
-Reverse T3 does not act the same as T3, but binds to same receptors, produces sx of hypothyroidism-fatigue, ha, fluid retention
Subclinical Hypothyroid
-increased TSH
-NL free T4 and T3
Iatrogenic Hypothyroidism
-radioactive iodine ablation therapy
-posoperative thyroidectomy
-overdose of antithyroid meds such as methimazole
S/S Iatrogenic Hypothyroid
-bradycardia
-edema
-hoarseness
-extreme weakness
-muscle fatigue
-arthalgia
-cramps
-cold intolerance
-constipation
-weight gain
-dry skin
-hair loss
-brittle nails
-slow DTR's
Hypoactive bowel sounds
-puffy eyes
Labs-hypothyroid
increases TSH
T4 low to nl
-hyponatremia
-hypoglycemia
TX-hypothyroid
-Levothyroxine
-average full replacement dose of levothyroxine is approx....1.7 mcg/kg/day (100-125)
-long half-life, therapeutic after 4-6 weeks
-30 min before breakfast on empty stomach
-reduces effect of metformin and other diabetic meds
Myxedema Coma
-extreme manifestation of hypothyroidism
-caused by infection
Myxedema manif
-deterioration of mental status
-do not have to be comatose to dx
-almost exclusively in pt >60
-occurs in winter months-inability to sense temp change
Features-Myxedema
-usually longstanding hypothyroidism
-same as hypothyroidism
-precipitating factors include infections, particularly pneumonia and urosepsis
-failure to reinstate thyroid replacement therapy
-classic myxedma face
-goiter
-temp usually less than 35.5 (95.9)
-hypotension and bradycardia
-resp dx may lead to sleep apnea
Features-myexdema
-severe fatigue
-poor drug metabolism
-decreased CO
-increased systemic vascular resistance
-ventricular arrythmias
-decreased plasma volume leads to increased capillary permeability and fluid shift to extracellular spaces including possible pericardial effusions
-decreased GFR due to poor CO
-hyponatremia due to poor NA reabsorption by kidneys
-decreased intestinal motility
-absence of fever in presence of infection
-shock
-seizures due to hyponatremia
Labs and Testing
-thyroid hormone levels
-creatine kinase
-ABG
-CXR-cardiomegally, pleural effusions
-EKG
-Hyponatremia with low osmolality common
-increased creatinine
-hypoglycemia
-pan cultures for spesis
TX-Myxedema
-protect airway
-fluid replacement
-Tx hyponatremia and hypoglycemia
-Levothyroxine 400mcg IV x 1 dose then 100mcg IV daily until pt can take PO
-support hypotension and breadycardia
-slow rewarming
-may require Swan Ganz
-Hydrocortisone admin until adrenal insufficiency has been ruled out. IV 100mg q 8. failure to tx can result in adrenal crisis
thyroid Cancer
-painless neck swelling
-pain, hoarseness, hemoptysis
-nodule enlarges over time
-stony hard consistency
thyroid cancer-labs
-Thyroid function test often NL
-TSH measured to exclude primary thyroid
-fine needle biopsy
-hot nodules on radionuclide scan are benign
thyroid cancer-management
-surgical resection and partial thyroidectomy
-replacement therapy with T4
-Radioactive ablation
Pearls of Wisdom-hyperthyroid
-common cause of thyrotoxicosis is Graves
-No other disease has goiter and bilateral exophthalmia
Posturing
Decorticate:
cause-diffuse and severe cortical dx, seen in deep coma
indicates MIDBRAIN dx

Decerebrate:
tentorial herniation-usually paralysis of 3rd cranial nerve
usually level of BRAIN STEM

Seen in myxedema coma
hyponatremia in myxedema
result of decreased free water clearance. Elevated levels of antidiuretic hormone and/or diminished blood flow to the kidneys are believed to be responsible for the inability to excrete free water. Hypoatremia is classically associated with a low serum osmolality
elevated CK in myxedema
pt can be mis-diagnosed with MI
result from altered membrane permeability
ecg changes-bradycardia, decreased voltage, non-specific ST and T changes, varying types of block and a prolonged QT interval.
Pearls of Wisdom-Myxedema
-the extreme manifest ion of hypothyroidism is common but lethal
-ICU needed
-IV levothyroxine
-cotrocortisone admin until adrenal insuff ruled out
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