Thyroid/Endocrine

Question 1

Anterior/Posterior Pituitary Hormones

Answer 1

Anterior:

• GH (growth hormone)
• Prolactin
• FSH (follicle stimulating hormone)
• LH (lutennizing hormone)
• ACTH (adrenocorticotropic hormone)
• TSH (thyroid stimulating hormone)

Posterior:

• Oxytocin (birth contractions, positive feed back)
• ADH (antidiuretic hormone)

Question 2

Posterior Pituitary Replacement Meds

Answer 2

ADH replacement meds reabsorb water in the renal tubules, increase GI motility and contraction of vascular smooth muscle.

Meds and Route:

• DDVAP (desmopressin acetate)
• pitressin (vasopressin)
• intranasal or injected

Oxytocin replacement meds stimulate uterus, and cause lacteal glands to contract, ejecting milk.

Meds and Route:

• oxytoicn (Pitocin)
• injection

Question 3

Thyroid and Disorders

Answer 3

The thyroid has 3 functions:

1. Stimulates energy use.
2. Stimulates the heart.
3. Promoted growth and development.
   - The thyroid uses iodine (found in salt, seafood, bread, and milk) to produce and release 2 active hormones, T3 and T4.

Hypothyroid: 
-Thyroid gland does not make enough hormones.
Symptoms:
-Fatigue
-Weight gain
-Cold intolerance
-Dry brittle hair or hair loss
-Dry skin
-Goiter 
-Hashimotos Disease (autoimmune disorder which thyroid gland may be totally destroyed by immunologic process).

Hypothyroid Treatment:

• Natural is desiccated thyroid USP (armour thyroid).
• Synthetic is levothyroxine (levoxyl, synthroid), and liothyronine (cytomel).
• *Levothyroxine Directions and Indications**
• Take on an empty stomach at least 30-60 min before eating, with 8oz water.
• Need monthly lab testing to monitor dose.
• Ferrous sulfate, antacids, and calcium decrease absorption.
• Phenytoin, warfarin, lanoxin, insulin increase absorption.

Hyperthyroid:
-Too many hormones
Symptoms:
-Tachycardia
-Nervousness/insomnia
-Heat intolerance
-Weight loss
-Exopthalmos
-Graves disease (autoimmune, abnormal stimulation of thyroid by thyroid-stimulating antibodies, act as TSH receptors).

Hyperthyroid Treatment:

• Meds help control hyperthyroidism and thyrotoxicosis (thyroid storm) especially prior to surgery or radioactive iodine treatment.
• Propylthiouracil (PTU) and Methimazole (Tapazole).
• Potassium iodide (SSKI, Lugols solution) is used to prep for thyroidectomy. Reduces size of thyroid. Will get a brassy taste, dyspepsia. Monitor agranulocytosis.

Question 4

Adrenal Glands and its Hormones

Answer 4

Adrenal glands produce 3 steroid hormones: SSS

1. Glucocorticoids influence carb metabolism (SUGAR)
2. Mineralocorticoids modulate salt and water balance (SALT)
3. Androgens for expression of sexual characteristics (SEX)
4. Glucocorticoids:
   - Cortisol is the most important.
   - Physiologic effects are carb protein fat metabolism, vascular permeability, skeletal muscle function, mood (CNS), and stress response.
5. Mineralocorticoids:
   - Aldosterone is the most important.
   - Renal: If there is an aldosterone insufficiency, the kindneys will be affected and result in hyponatremia, hyperkalemia, acidosis, cellular dehydration, and reduction in ECF).
   - Cardiac: If aldosterone is high, dysrhythmias and ischemia.
   - Aldosterone secretion is regulated by RAAS system.
6. Androgens for male/female sexual characteristics.

Question 5

Addisons Disease

Answer 5

Adrenal Cortical Insufficiency:

• Layers of the adrenal cortex are destroyed.
• Adrenal Cortical hormones are deficient.
• Autoimmune, rare.

Symptoms:

• Bronzed skin patches.
• Changes of distribution of body hair.
• GI disturbances.
• Weakness.
• Hypoglycemia.
• Postural hypotension (over 20 difference a problem).
• Weight loss.

Adrenal Crisis:

• Profound fatigue
• Dehydration
• Low BP (vascular collapse)
• Renal shut down
• Decreased NA, Increased K

Treatment:

• If cortisol deficient, give synthetic glucocorticoid like prednisone or hydrocortisone.
• If aldosterone deficient, give synthetic mineralocorticoid like fludrocortisone.

Question 6

Cushing Syndrome

Answer 6

Cushing Syndrome:

• Excess glucocorticoid hormone.
• Caused by excess ACTH production from pituitary or adenoma (a tumor).
• Signs are a buffalo hump, moon face, hirsutism (excessive hair growth), glucose impairment, HBP, striae, fatigue etc, see the PowerPoint.

Treatment:

• If adrenal/pituitary adenoma, or carcinoma, remove it.
• If bilateral removal is necessary, replacement therapy of glucocorticoids and mineralocorticoids needed for life.