Hypothyroidism NCLEX review notes for students who are prepping to take the NCLEX exam. The endocrine system is made-up of many disorders, such as hypothyroidism and hyperthyroidism.
As a student prepping for NCLEX, it is very important you know the differences between the two conditions.
As the nurse taking care of the patient with hypothyroidism it is important you understand the signs and symptoms, pathophysiology, causes, nursing interventions, and medical treatments.
Don’t forget to take the quiz on hypothyroidism vs hyperthyroidism.
In this NCLEX review, you will learn the following:
- Pathophysiology of the thyroid gland
- Negative feedback loop of thyroid gland
- Signs and symptoms of hypothyroidism
- Causes of Hypothyroidism
- Nursing Interventions
- Medications for Hypothyroidism
- Treatments
Lecture on Hypothyroidisim
Hypothyroidism
Definition: Low secretion of thyroid hormone
Key Players:
Thyroid: produces thyroid hormones that play a big role in body metabolism, regulation of body temperature, and growth/development.
- These hormones are known as: T3 Triiodothyronine, T4 Thyroxine (most important when talking about hypo/hyper thyroidism), and Calcitonin.
- Thyroid can NOT make thyroid hormones without iodine which comes from foods (if you don’t have enough iodine in your diet…low t3 and t4…this leads to hypothyroidism and if you have too much hyperthyroidism)
T3 & T4: plays a huge role in:
- burning calories
- how new cells replace dying cells
- how fast we digest food
- stimulate sympathetic nervous system (alertness, quick responsiveness/reflexes)
- increases body temperature and heart rate
- brain development
- muscle contraction
- fertility
- regulates TSH (thyroid-stimulating hormones through the negative feedback loop)
TSH: produced from the anterior pituitary gland that stimulates T3 and T4 production
Negative Feedback Loop of Thyroid Hormone Production
Hypothalamus produces -> TRH (Thyrotropin-releasing hormone)…this causes the Anterior Pituitary Gland to produce ->TSH (thyroid-stimulating hormone)….this cause the thyroid gland to produce-> T3 & T4
- There can be problems with the feedback system where the pituitary gland is not stimulating the thyroid gland enough so hormones are not produced or the thyroid is not receptive to the TSH from the pituitary gland.
Thyroid problems diagnosed with blood tests that look at T3, T4 (free) levels, and TSH to make a conclusive diagnosis.
Signs and Symptoms Hypothyroidism
Let the condition’s name help you: everything is going to be LOW and SLOW due to the body working at a very slow metabolism rate
- Weight Gain
- Unable to tolerate cold
- Possible goiter from constant thyroid stimulation to get the thyroid gland to produce T3 and T4 MOST COMMON SIGN IN HASHIMOTO’S
- Extremely tired and fatigued
- Slow heart rate
- Thinning and brittle hair
- Depression
- Constipation
- Memory loss
- Myxedema: swelling of the skin (eyes and face) that gives it a waxy appearance
- Dry skin
- Joint, muscle pain
- Menstrual problems (irregular or heavy periods)
***early signs are feeling tired and fatigue…then as hypothyroidism progresses the patient starts to exhibit other symptoms
Causes of Hypothyroidism
Affects mainly women (middle-aged to older-aged)
Hashimoto’s thyroiditis (most common cause): autoimmune disorder where the body attacks the thyroid gland which causes it to stop releasing T3 and T4. GOITER LIKELY
Iodine deficiency: not consuming enough foods with iodine
Pituitary Tumor: stops the anterior pituitary from secreting TSH which stimulates the thyroid gland to secrete T3 and T4.
Treatment for hypothyroidism:
- Thyroid Hormone replacement (Synthroid, Thyrolar, Cytomel)
- Avoid sedatives and narcotics because these patients are very sensitive to them and they increase the chances of myxedema coma
Nursing Interventions for Hypothyroidism
Monitor for Myxedema Coma: caused from uncontrolled low thyroid production usually due to illness, abrupt stopping thyroid replacement medication, or removal of thyroid gland
- Presents with everything shutting down (or slowing down to the point of death)
- Temperature regulation doesn’t work (hypothermia)
- Extreme drowsiness
- Respiratory failure, bradycardia (remember t3 and t4 play a role in sympathetic system)
- Low blood glucose, sodium levels…progress to a coma
Monitor vitals sign: HR, BP, EKG
Monitor weight
Keep patient warm and assess for constipation (very uncomfortable)…encourage fluids
Medications for Hypothyroidism
Thyroid hormone replacement:
- Cytomel “Liothyronine sodium”
- Thyrolar “Liotrix”
- Synthroid “Levothyroxine” MOST COMMON
Patient education:
- Don’t abruptly stop taking (takes a while for signs and symptoms to improve)
- Take at the same time every day in the morning without food
- Don’t take within 4 hours of multivitamins, GI medications like Carafate, aluminum hydroxide, simethicone….decreases absorption of thyroid medication
- Watch for signs and symptoms of toxicity which would present as signs and symptoms of hyperthyroidism (fast heart, feeling hot, sweating)
Note patients with hypothyroidism are sensitive to narcotics like opioids (avoid dilaudid, morphine, fentanyl) and other sedatives (could lead to myxedema coma). Instead use alternatives for pain as prescribed like non-narcotics (Tylenol, Ibuprofen)
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