Endocrine System Flashcards
How does the Negative Feedback System/Mechanism work?
This mechanism reverses changes that occurred
Brings body back to homeostasis
How does the Positive Feedback System/Mechanism work?
This mechanism reinforces changes that occurred
What regulatory hormones does the hypothalamus produce? What organ do these hormones act on?
Releasing hormones and Inhibiting hormones
These hormones act on the Anterior Pituitary Gland and tell it to release or inhibit release of hormones
What two hormones are synthesized in the hypothalamus?
Antidiuretic hormone
Oxytocin
What gland stores and releases Antidiuretic hormone and Oxytocin?
Posterior Pituitary Gland
The Anterior Pituitary Gland is regulated by which gland?
Hypothalamus
What are tropic hormones?
Hormones that send messages to other glands and tell those glands to release their specific hormones
What hormones are classified as tropic hormones?
Thyroid Stimulating Hormone
Adrenocorticotropic Hormone
Follice Stimulating Hormone
Luteinizing Hormone
What hormones come from the Anterior Pituitary Gland?
Thyroid Stimulating Hormone Adrenocorticotropic Hormone Follice Stimulating Hormone Luteinizing Hormone Growth Hormone Prolactin
How does Thyroid Stimulating Hormone (TSH) work?
Stimulates the thyroid to release thyroid hormones (T3 and T4)
How does Adrenocorticotropic Hormone (ACTH) work?
Stimulates the adrenal cortex to release glucocorticoids (cortisol)
If there is a malfunction of the Anterior Pituitary Gland, what will happen with secretion of its hormones?
There will either be too little or too much of various hormones released
The Posterior Pituitary Gland is an extension of what?
Extension of the hypothalamus
Does the Posterior Pituitary Gland synthesize its hormones?
No
It only stores and releases hormones (Antidiuretic Hormone and Oxytocin)
When would increased levels of Adrenocorticotropic Hormone be present in the body?
During periods of stress, trauma, infection, illness, etc.
Levels of Adrenocorticotropic Hormone (ACTH) would be increased because this hormone is stimulating the Adrenal Cortex to release glucocorticoids (cortisol)
How does Antidiuretic Hormone (ADH) - also known as Vasopressin) - work?
It regulates fluid volume within the body
When released, it tells the kidneys to reabsorb water, thus conserving water within the body
Which endocrine gland can possibly be palpated?
Thyroid Gland
What hormone stimulates the thyroid to release T3 and T4?
Thyroid Stimulating Hormone
What three hormones come from the thyroid?
Triiodothyronine (T3)
Thyroxine (T4)
Calcitonin
What do T3 and T4 do within the body?
Regulate cellular respiration of glucose and fatty acids
Control metabolism throughout entire body and all bodily processes
In order for T3 and T4 to be synthesized by the thyroid, what must be in the diet?
Protein and Iodine
What does calcitonin do within the body?
Inhibits reabsorption of calcium
Lowers serum calcium levels
When is calcitonin stimulated?
When serum calcium levels are too high (hypercalcemia)
It will take excess calcium and store it in the bones and teeth
What hormone is produced by the Parathyroid Gland?
Parathyroid Hormone (PTH)
What does Parathyroid Hormone (PTH) do?
Raises serum calcium levels:
Pulls calcium from bones
Encourages small intestine to absorb more calcium
Encourages the kidneys to reabsorb more calcium
When is Parathyroid Hormone (PTH) secreted?
During hypocalcemia
The Adrenal Medulla releases what hormones?
Epinephrine and Norepinephrine
What effect do Epinephrine and Norepinephrine have on the body?
Act on alpha one, beta one and beta two receptors
Increase the heart rate, increase the force of cardiac contraction, bronchodilation, vasoconstriction of peripheral arteries, vasodilates skeletal muscle arterioles, tells the liver to convert glycogen to glucose for energy
When are Epinephrine and Norepinephrine released?
Released during stressful times (flight or fight) to manage stress response and keep body safe
The Adrenal Cortex releases what hormones?
It releases corticosteroids, which include:
Glucocorticoids (Cortisol)
Mineralocorticoids (Aldosterone)
Gonadocorticoids (Androgens)
What hormones released by the Adrenal Cortex are essential for life?
Mineralocorticoids
Glucocorticoids
What tropic hormone is released to promote the release of Cortisol from the Adrenal Cortex?
Adrenocorticotropic Hormone (ACTH)
What is the target organ of Mineralocorticoids (Aldosterone)?
Kidneys
What is the target organ of Glucocorticoids (Cortisol)?
Many systemic body tissues
What does Glucocorticoids (Cortisol) do for the body?
Provides energy sources to the body during stress (because it tells the liver to convert glycogen to glucose)
What organ is both an endocrine and exocrine gland?
Pancreas
What hormones does the Pancreas synthesize and release?
Insulin
Glucagon
What specific cells synthesize insulin?
Beta cells
What specific cells synthesize glucagon?
Alpha cells
Where do beta and alpha cells live within the Pancreas?
Islet of Langerhans
When ____ cells are destroyed, insulin cannot be synthesized
beta
When is insulin released by the Pancreas?
When glucose levels are elevated (hyperglycemia)
How does insulin work within the body?
It opens the cells and allows glucose to travel inside of the cells
The cells can then use glucose for energy
Without insulin, what happens to the cells?
They starve. Glucose cannot get inside of the cells and the cells do not have glucose to use as energy
When is glucagon released by the Pancreas?
When glucose levels are decreased (hypoglycemia)
How does glucagon work within the body?
Glucagon stimulates the liver to convert glycogen to glucose
Glucose is the usable form of energy for the cells
What two endocrine disorders can occur if Antidiuretic Hormone isn’t regulated properly?
Diabetes Insipidus
Syndrome of Inappropriate Antidiuretic Hormone
What is Diabetes Insipidus? What happens during this issue?
Underproduction of Antidiuertic Hormone
Unable to conserve water via kidneys
Increased urine output, urine not concentrated
Urine specific gravity < 1.005
What is a priority nursing concern with Diabetes Insipidus? What is a priority nursing intervention?
Concern: Dehydration
Intervention: Promote fluids
What is Syndrome of Inappropriate Antidiuretic Hormone? What happens during this issue?
Overproduction of Antidiuertic Hormone
Conserve too much water via kidneys
Decreased urine output, urine extremely concentrated
Urine specific gravity >1.030
What is a priority nursing concern with Syndrome of Inappropriate Antidiuretic Hormone? What is a priority nursing intervention?
Concern: Fluid overload
Intervention: Restrict fluids, monitor respiratory system for breathing complications (pulmonary edema)
What is the basic definition of hypothyroidism?
Too little thyroid hormone (T3 and T4)
Metabolic rate slowed
What is the basic definition of hyperthyroidism?
Too much thyroid hormone (T3 and T4)
Metabolic rate sped up
Describe primary hypothyroidism
Thyroid gland isn’t functioning appropriately
Thyroid gland is unable to synthesize and release T3 and T4 into circulation
Anterior Pituitary Gland is releasing additional Thyroid Stimulating Hormone (TSH) in attempts to stimulate the thyroid gland.
(T3 and T4 are low, TSH is high)
Describe secondary hypothyroidism
Anterior Pituitary Gland is not working. It is not synthesizing and releasing Thyroid Stimulating Hormone (TSH)
Thyroid gland isn’t being stimulated, so it cannot release T3 and T4 into circulation
(TSH is low thus causing T3 and T4 to be low)
Describe primary hyperthyroidism
Thyroid gland isn’t functioning appropriately
Thyroid gland is over synthesizing and releasing T3 and T4 into circulation
Anterior Pituitary Gland is not releasing additional Thyroid Stimulating Hormone (TSH) in attempts to slow the thyroid gland down
(T3 and T4 are high, TSH is low)
Describe secondary hyperthyroidism
Anterior Pituitary Gland is not working. It is over synthesizing and releasing Thyroid Stimulating Hormone (TSH)
Thyroid gland is being over stimulated, so it is releasing additional T3 and T4 into circulation
(TSH is high thus causing T3 and T4 to be high)
What are some reasons hypothyroidism may occur?
Thyroid gland malfunction Anterior Pituitary Gland malfunction (TSH secretion insufficient) Hashimotos Thyroiditis Insufficient iodine in the diet Thyroid gland removed
List signs and symptoms of hypothyroidism
Fatigue Mental Dullness Bradycardia Hypoventilation Cold intolerance Consitpation Weight gain Dry skin and hair Heart failure Hyperlipidemia Myxedema (Coma)
What are some reasons hyperthyroidism may occur?
Graves Disease
Goiter
List signs and symptoms of hyperthyroidism
Heat intolerance Tachycardia Palpitations Hypertension Chest Pain Increased Appetite Weight Loss Frequent stools Fatigued, Irritable Nervousness Tremulous Exopthalmos (with Graves)
What medication is given to treat hypothyroidism?
Levothyroxine (Synthroid)
What type of disease is Type One Diabetes Mellitus classified as?
Autoimmune disease
Body attacks beta cells (that live within the Islet of Langerhans in the Pancrea)
When beta cells are all killed off, insulin can not be synthesized any longer
What does a Type One Diabetic patient need to survive?
Exogenous insulin administration daily for life
What is the most prevalent form of Diabetes Mellitus?
Type Two
Explain what happens within the body in Type Two Diabetes Mellitus
Insulin secretion is impaired:
Beta cells are decreased
Beta cells aren’t as responsive when glucose levels are elevated, therefore they will not release as much insulin as quickly
The tissues within the body are less responsive to insulin
How can Type Two Diabetes Mellitus be controlled?
Through proper diet and exercise (weight loss)
Oral medications
Insulin
If a patient is diagnosed with pre-diabetes, how will they manage the disease?
Diet, exercise, weight loss
When done properly, they can avoid the diagnosis of Diabetes Mellitus
What are acute complications of Diabetes Mellitus? What is most concerning?
Hypoglycemia
Hyperglycemia
Ketoacidosis
Hypoglycemia is the most concerning, it can kill a patient first
What can cause hyperglycemia?
Stress Illness Food Not enough medications Not adhering to medication regimen
List the signs and symptoms of hyperglycemia
Polyuria Polyphagia Polydipsia Glycosuria Nocturia Ketouria Blurred Vision Fatigue, Lethargy, Headache Abdominal Pain Eventual Coma
How can hyperglycemia be treated?
Dietary changes
Increase physical activity
Oral agents
Insulin
What can cause hypoglycemia?
Undereating
Skipping meals
Too much insulin
Exercise
What patient population is at increased risk for hypoglycemia?
Older adults taking beta blockers
Masked signs of hypoglycemia – this is called Hypoglycemia Unawareness
List signs and symptoms of hypoglycemia
Hunger Shaking Tremulous Sweating Palpitations Headache Irritable Confusion Eventual Seizures, Coma
If the nurse suspects a patient is hypoglycemic, what is the first step?
Check the blood sugar!
Always check the blood sugar so a baseline value is obtained
When should the nurse initiate the hypoglycemia protocol?
If the blood sugar is less than 70 mg/dL
If the patient’s blood sugar is less than 70 mg/dL and the patient is alert and oriented, following commands, what should the nurse do?
Administer 15 to 20 g of a fast acting carb: 4-6 ounces of juice or regular soda, 6 to 8 hard candies
If the patient’s blood sugar is less than 70 mg/dL and the patient is lethargic, unconscious and/or uncooperative, what should the nurse do?
Administer Glucagon (SubQ or IM) If there is IV access, give Dextrose
How does a patient prevent long term complications of Diabetes Mellitus?
Control blood sugar Control Hgb A1C Diet Exercise Weight management Adhere to medication regimen
What macrovascular damages occur with long term Diabetes Mellitus complications?
Atherosclerosis Arteriosclerosis HTN Hyperlipidemia Increased risk of having a myocardial infarction or stroke
What microvascular damages occur with long term Diabetes Mellitus complications?
Retinopathy
Nephropathy
What are some long term complications of Diabetes Mellitus?
Neuropathy Increased risk for infection Slow/poor wound healing Microvascular complications Macrovascular complications
