Module 6 (a) Flashcards
Thyroid Hormones
-Physiologic Effects
Thyroid hormone helps every body cell regulate metabolism
- Affects fetal development
- Regulates O2 consumption and heat production
- Affects CV muscle contraction
- StimulatesBone resorption
- Permits normal glucose metabolism ,absorption, and storage
- Functions in the synthesis and breakdown of lipids
- Affects rate of metabolism of many hormones and drugs
Thyroid Hormones
-Heat Regulation?
- Hypothyroidism patients report increased sensitivity to COLD
- Hyperthyroidism patients report increased sensitivity to HEAT
Thyroid Glad
-Endocrine System
- Regulated by Thyroid stimulating hormone (TSH)
- Thyroid glad produces
- Triiodothyronine (T3)
- Thyroxine (T4)
Thyroid Disorders
-Stats
- 20 million Americans affected with 60% unaware of their condition
- Women are 5-8x more likely than men to have thyroid problems
- Undiagnosed Thyroid dz can lead to risk for
- CVD< osteoporosis, and infertility - Most Thyroid Dz are LIFE-LONG conditions
Thyroid Disorders
-Undiagnosed Hypothyroidism in Pregnancy
- Undiagnosed hypothyroidism in pregnant women leads to:
- Miscarriage
- Preterm delivery
- Severe developmental problems
Thyroid Regulation
-Hypothalamic-Pituitary-Thyroid Axis?
- Hypothalamus Produces “Thyroid Releasing Hormone”
- TRH is MAIN HORMONE that regulates thyroid gland - TRH stimulates the anterior pituitary to produce Thyroid Stimulating Hormone “TSH”
- TSH stimulates thyroid glad to secrete T3 and T4 from pituitary gland
- TRH and TSH are negative feedback relationship
- Too much hormone can lead to hyperthyroidism
- Too little hormone leads to hypothyroidism
Abnormalities of Thyroid Gland
-Types?
- Structural & Functional abnormalities
- Cysts
- Nodules
- Overactive or under-active thyroid
- Cancer
Structural & Functional Abnormalities of the Thyroid
- Goiter’s are the MOST COMMON structural abnormality of the thyroid gland
- Enlargement of the thyroid - Tumors (Nodules)
Structural & Functional Abnormalities of the Thyroid
-Characteristics
- Asymptomatic
- Hyperthyroid or hypothyroid symptoms
- Neck swelling
- Airway compression
- Difficulty swallowing
Structural & Functional Abnormalities of the Thyroid
-Thyroid Nodules
- Abnormal overgrowth of tissue
- Can be filled with liquid or solid
- Classified as hot, warm or cold according to amount of iodine isotope in the nodule compared to amount in the rest of the thyroid gland
- Hot Nodules are benign
- Cold Nodules can be malignant - Often Asymptomatic
- Iodine deficiency regions are impacted
- More likely in women w/ advancing age
Structural & Functional Abnormalities of the Thyroid
-Hot Vs. Cold Nodules
- Hot Nodules are benign
- Cold Nodules can be malignant
Nodules are usually asymptomatic; monitor for ANY changes
Structural & Functional Abnormalities of the Thyroid
-Thyroid Cysts
- Thyroid cysts are nodules that contain LIQUID
- Usually benign or non-cancerous
- May be asymptomatic or c/o
- Difficulty breathing, swallowing or vocal changes - May reoccur after draining
Structural & Functional Abnormalities of the Thyroid
-Complex cysts or mixed Echogenic Nodules?
- Have both liquid and solid components
2. Could be cancerous
Structural & Functional Abnormalities of the Thyroid
-Tests for Thyroid Cysts
- Ultrasound
- Biopsy (Refer to specialist for US guided procedure)
- Thyroid Scan
- Suspicion if cyst is secreting hormones
- If cyst is producing hormone, it is ACTIVE and can cause HYPERTHYROIDISM
Structural & Functional Abnormalities of the Thyroid
-Thyroid Scan Test
- Radioactive Iodine Pill given to Patient to help track iodine as it moves through thyroid gland
- SHOULD NOT be performed on pregnant or nursing mother
Structural & Functional Abnormalities of the Thyroid
-Goiter
- Abnormal enlargement of the thyroid gland
- D/T inflammation of thyroid gland or iodine deficiency - May be Asymptomatic
- Iodine deficiency
- May occur in hyper, hypo, or euthyroid states
S/S
Swelling, cough, dyspnea, throat tightness and hoarseness
Structural & Functional Abnormalities of the Thyroid
-Goiter Patho
- Increased signaling of TSH receptor to produce MORE hormone
- Ignoring feedback system - Leads to hypertrophy of the gland
-In Hypothyroid state
—(Body realizes there is lack of hormone and increases TSH)
-In Hyperthyroidism
—(Excess stimulation of TSH receptors even w/ normal hormone levels
Structural & Functional Abnormalities of the Thyroid
-Risk Factors
- Heredity
- Female Gender
- Age over 40
Structural & Functional Abnormalities of the Thyroid
-Conditions That can cause a Goiter?
- Graves Dz (Autoimmune)
- Hashimoto’s Dz (Autoimmune)
- Nodular Goiter
- Thyroiditis
- Thyroid Cancer
- Exposure to radiation
Hyperthyroidism
-Definition
-Hyperthyroidism is a clinical syndrome caused by:
1. Excess production OR release of thyroid hormone
AND
2. Clinical manifestations