Med-Surg II Exam 4: Metabolic & Endocrine/Thyroid Disorders

Regulating mechanism - ANSWER Hypothalmus -TRH=TSH-releasing hormone Anterior Pituitary -TSH=Thyroid stimulating hormone Thyroid -produces thyroxine hormones -metabolism & development -bone growth -ment ...

Regulating mechanism - ANSWER Hypothalmus -TRH=TSH-releasing hormone Anterior Pituitary -TSH=Thyroid stimulating hormone Thyroid -produces thyroxine hormones -metabolism & development -bone growth -mental development -metabolic use of energy -blood pressure and heart rate -muscle tone -digestion -reproduction Hypothalmus→TRH→Anterior pituitary→TSH→Thyroid→Thyroxine Factors affecting thyroid function - ANSWER Nutrients contribute to proper production of thyroid hormones: -iron, iodine, tyrosine, zinc, selenium, vit. E, B2, B3, B6, C, D Factors that increase conversion of T4 to RT3: -stress -trauma -low calorie diet -inflammation (cytokines, etc) -toxins -infections -liver/kidney dysfunction -certain medications Factors that inhibit proper production of thyroid hormones -stress -infection, trauma, radiation, medications -fluoride (antagonist to iodine) -toxins: pesticides, mercury, cadmium, lead -autoimmune disease: celiac Factors that increase conversion of T4 to T3 -Selenium -zinc Factors that improve sensitivity to thyroid hormones -vitamin A -exercise -zinc Hyperthyroidism Manifestations - ANSWER -intolerance to heat -fine, straight hair -bulging eyes -facial flushing -enlarged thyroid -tachycardia -↑ systolic BP -breast enlargement -weight loss -muscle wasting -localized edema -menstrual Δ's (amenorrhea) -tremors -diarrhea -finger clubbing Graves' Disease - ANSWER -most common cause of hyperthyroidism -toxic diffuse goiter -autoimmune disorder -antibodies attach to TSH receptors -thyroid gland increases number and size of glandular cells -enlarges gland, forms goiter, and overproduces thyroid hormones (thyrotoxicosis) -can occur at any age -most often women between 20 & 40 years -women 10X more often than men Graves' Disease Sx's - ANSWER -sweating -exopthalmos -goiter -arrythmia and tachycardia -nausea and diarrhea -oligomenorrhea in females -muscle weakness -tremor -headache -weight loss -nervousness -emotional instability Management of hyperthyroidism - ANSWER Beta-Blockers - Order of administration: 1 -decreases sympathetic hyperactivity -partially blocks peripheral conversion of T4 to T3 (propranolol) Propylthiouracil (PTU) - Order of administration: 2 -blocks synthesis of thyroid hormone -decreases conversion of T4 to T3 -faster onset of action than methimazole -preferred in pregnancy Methimazone - Order of administration: 2 -Blocks synthesis of thyroid hormone -teratogenic Iodide - Order of administration: 3 or 4 -inhibits release of stored thyroid hormone -Administer only after synthetic pathway has been bloked by PTU or Methimazole. Steroids - Order of administration: 3 or 4 -decrease peripheral conversion of T4 to T3 -may treat the auto-immune process in Graves' disease. Diagnostic criteria for Thyroid Storm - ANSWER Thermoregulatory Dysfunction - 99-99.9° F (37.2-37.7° C) = 5 - 100-100.9°F (37.8-38.2° C) = 10 - 101-101.9°F (38.3-38.8° C) = 15 - 102-102.9°F (38.9-39.3° C) = 20 - 103-103.9°F (39.4-39.9° C) = 25 - ≥104°F (40.0°C) = 30 CNS -agitation = 20 -delerium, psycosis, lethargy = 30 -seizure, coma = 40 GI/Hepatic Dysfunction -diarrhea, N/V, abd. pain = 10 -severe jaundice = 20 Tachycardia - 99-109 bpm = 5 - 110-119 bpm = 10 - 120-129 bpm = 15 - 130-139 bpm = 20 - ≥ 140 bpm = 25 Congestive Heart Failure -pedal edema = 5 -bibasal rales = 10 -pulmonary edema = 15 -atrial fibrillation present = 10 -precipitant history present = 10 **A score ≥45 is highly suggestive of thyroid storm; 25-44 supports the diagnosis, <25 marks thyroid storm unlikely** Precipitants of thyroid storm - ANSWER Medical -infection/sepsis -CVA -MI -CHF -pulmonary embolism -visceral infarction -emotional stress -acute manic crisis Trauma -thyroid surgery -non-thyroid surgery -blunt and penetrating trauma to the thyroid gland -vigerous palpation of the thyroid gland -burns Endocrine -Hypoglycemia -DKA -Hyperosmolar nonketotic coma Drug-Related -Iodine 131 therapy -premature withdrawal of antithyroid therapy -ingestion of thyroid hormone -iodinated contrast agents -Amiodarone therapy -Iodine ingestion -anesthesia induction -misc. drugs: chemotherapy, pseudophedrine, organophosphates, aspirin Pregnancy-Related -toxemia of pregnancy -hyperemesis gravidarum -parturition and the immediate post-partum period Treatment of thyroid storm - ANSWER Step 1: Block peripheral effect of thyroid hormone -IV beta-blocker Step 2: Stop the production of thyroid hormone -PTU or Methimazole -Dexamethasone or Hydrocortisone Step 3: Inhibit hormone release -Iodine 2-3 hours after anti-thyroid medication Thyroid storm causes - ANSWER -Surgery -Radioactive Iodine Therapy -Severe illness Thyroid storm diagnosis - ANSWER Clinical -tachycardia -hyperpyrexia -thyrotoxicosis Sx's Labs -↓ TSH -↑ T4 - FT4 Thyroid storm treatment - ANSWER -Propranolol IV vs. Verapamil IV -PTU, Methimazole -Sodium Iodide -Acetominophen, cooling blankets -Plasmapharesis (rare) -Surgical (rare) Hypothyroidism - ANSWER -occurs most often in women 30 to 60 y/o -women affected 7 to 10X more than men -incidence increases with age -most cases from: -thyroid surgery -radioactive iodine treatment -association between development of hypothyroidism and DM -Three types: -Primary - Disease of the thyroid -Secondary - Disease of the pituitary -Tertiary - Disease of the hypothalmus Hypothyroidism Manifestations - ANSWER -intolerance to cold -receding hairline -facial & eyelid edema -dull-blank expression -extreme fatigue -thick tongue, slow speech. -anorexia -brittle hair and nails -menstrual disturbances -constipation -muscle aches and weakness -dry skin - coarse & scaly -lethargy -apathy -hair loss Late clinical manifestations: -subnormal temp -bradycardia -weight gain -↓ LOC -thickened skin -cardiac complications Thyroid Function Test Expectations for Hypothyroidism - ANSWER Serum T3 → decreased Serum T4 → decreased Free T4 Index →decreased T3 Resin uptake→decreased TSH → low in secondary or tertiary disease TSH → high in primary disease Hypothyroidism Diagnosis - ANSWER Normal thyroid state TSH = 0.4-4.0 mlU/L Free T4 = 0.8-2.7mg/dL Primary hypothyroidism TSH = >4.0 mlU/L Free T4 = Decreased Subclinical hypothyroidism TSH = >5.0-10.0 mlU/L Free T4 = Normal Hypothyroidism Causes - ANSWER -Hashimoto's Thyroiditis - # 1 cause (auto-immune) -Iodine deficiency (may be present in the developing world and developed world) -incidence reduced w/the use of iodanted salt -Congenital absence of thyroid -Congenital enzyme defect of thyroid -Post-ablative (RAI or surgery) -Drug induced -Lithium -Amiodrone Hypothyroidism nutritional support - ANSWER -Wild caught fish -Coconut oil -Seaweeds -High fiber foods -Fruits and vegetables -Probiotic rich foods -Sprouted seeds -Clean water -Bone broth Hypothyroidism - Foods to avoid - ANSWER -Cruciferous vegetables -Gluten -Fatty foods -Sugary foods -Processed foods -Coffee Hypothyroidism Interventions - ANSWER -patient education -drug therapy -prevention of myxedema coma -lifelong thyroid hormone replacement -most common is levothyroxine sodium (Synthroid) -low dose that is gradually increased mcg NOT mg -patient must take according to schedule and as directed Myxedema coma - ANSWER -rare, serious life-threatening complication of untreated or poorly treated hypothyroidism -decreased metabolism heart muscle becomes flabby and chamber size increases decreased CO -decreased perfusion + slowed cellular metabolism = tissue and organ failure -mortality rate is very high -can be caused by various events, drugs, or conditions