Unit 2: Chp 40: Assessment of Endocrine Function Flashcards
Endocrine Glands
- hypothalamus
- pituitary gland
- thyroid glands
- parathyroid glands
- gonads
- select cells of the pancreas (Islet cells)
What do the Endocrine Glands do?
secrete hormones that are chemical messengers that act on specific target tissues, resulting in physiological functions
-hormones are secreted directly into the blood system
Exocrine Glands
-lacrimal
-salivary
-sweat glands
>hormones are released from ducts
Function of the Endocrine System
directly associated w/ secretion and levels of circulating hormones
-primary, secondary, tertiary, and quaternary disorders
Primary Disorders
involve actual dysfunction to the endocrine gland
Secondary Disorders
dysfunction of the anterior pituitary gland
Tertiary Disorders
dysfunction of the hypothalamus
Quaternary Disorders
inability of the target tissue to respond to the hormone
How is the Secretion of Hormones Regulated?
via signals from the nervous system, levels of hormones in the blood, and chemical changes in the blood such as glucose, sodium, and potassium levels
-controlled by negative-feedback system
Negative-feedback System
increases hormone secretion when circulating levels are decreased
Safety Alert: Corticosteroids
pts prescribed corticosteroids for more than 10 to 14 days require “tapering” of the medication
- b/c of the effects of the exogenous corticosteroid on the hypothalamus, anterior pituitary, and adrenal cortex, the normal hormonal feedback system is interrupted
- abrupt withdrawal of the exogenous drug may lead to adrenal insufficiency; medical emergency; decreased blood pressure and hypoglycemia
Use of corticosteroids
for inflammation
- impact function of the negative feedback system
- b/c there are increased circulating levels of corticosteroid, the hypothalamus decreases secretion of corticotropin-releasing hormone; leads to decreased secretion of adrenocorticotropic hormone (ATCH) from anterior pituitary gland which results in decreased secretion of cortisol from the adrenal cortex
Hypothalamus
- small structure located beneath the thalamus
- shaped like a flattened funnel and forms the walls and floor of the third ventricle
- hormones produced and secreted by the hypothalamus act directly on other endocrine glands (ex: pituitary gland)
- connected to the pituitary gland by the infundibulum
- regulates anterior pituitary gland function through the secretion of hormones whose target tissue is the anterior pituitary gland
Pituitary gland
- located at the base of the brain
- communicates directly w/ hypothalamus
- anterior and posterior lobe
Anterior Pituitary Gland
- secretes follicle stimulating hormone (FSH) and luteinizing hormone (LH); major roles in female and male reproductive functions
- secretes thyroid-stimulating hormones
- releases adrenocorticotropic hormone (ACTH)
- secretes prolactin, growth hormone (GH), and melanocyte-simulating hormone
Posterior Pituitary Gland
secretes antidiuretic hormone (ADH) and oxytocin
Adrenal Glands
located on top of each kidney
-has inner cortex, the medulla, and a thick outer covering, the cortex
Adrenal Cortex
comprises 90% of the adrenal gland
- secretes Mineralocorticoids that control fluid balance through their effects on the kidneys; absorption of sodium and water and excretion of potassium
- secretes Aldosterone (primary mineralocorticoid)
- secretes glucocorticoids (primary is cortisol); have an effect on carbohydrate, protein, and fat metabolism; suppress inflammatory and immune functions
Adrenal Medulla
- under control of sympathetic nervous system
- catecholamines (norepinephrine and epinephrine) are secreted when stimulated by the SNS
Thyroid hormone
- produces triiodothyronine (T3), thyroxine (T4), and thyrocalcitonin (calcitonin)
- calcitonin decreases serum calcium levels
Parathyroid Glands
- secrete parathyroid hormone (PTH); in response to low calcium levels
- target organs of PTH are bones, kidneys, and small intestine
- PTH increases serum calcium levels
Gonads
sexual development and function are controlled by hormones secreted from ovaries and testes
- both ovaries and testes are controlled by tropic hormones released from the anterior pituitary gland based upon secretion of gonadotropin releasing hormone from the hypothalamus
- follicle-stimulating hormone (FSH) and luteinizing hormone (LH) stimulate maturation of male and female reproductive organs
- In males, FSH and LH stimulate testosterone
- In females FSH and LH stimulate estrogen and progesterone that influence development of secondary sexual characteristics, ovarian maturation, and ovulation
Pancreas
- located in upper left quadrant
- secretes pancreatic juices into the small intestine to aid in digestion
- blood glucose control by the islet cells
- releases insulin and glucagon
Assessment: History
-nurse completes a comprehensive history
-b/c the endocrine system affects homeostasis and metabolic activity, the nurse must assess changes in:
>nutritonal status
>physical appearance
>weight
>sleep pattern
>energy
>elimination pattern
>reproductive function
>evaluating family history for endocrine disorders; some are genetic