Chapter 45 Assessment & Management of Patients w/ Endocrine Disorders

Question 1

Endocrine System

Answer 1

Plays a vital role in orchestrating:
- Transportation of chemicals across cell membranes
- Growth & Metabolism
- Fluid & Electrolyte balance
- Acid-base balance
- Adaptation
- Reproduction

Question 2

What is the endocrine system composed of?

Answer 2

Pituitary gland, thyroid gland, parathyroid glands, adrenal glands, pancreatic islets, ovaries, & testes

Question 3

Pituitary Gland

Answer 3

AKA “Master Gland”

Regulates endocrine hormones
Primary role: Secrete hormones into bloodstream-> affects endocrine glands

Question 4

Anterior Pituitary Gland

Question 5

Posterior Pituitary Gland

Question 6

Hormones

Answer 6

Chemical transmitter substances prod in 1 organ/part of the body & carried to bloodstream to other cells/organs on which they have a specific regulatory effect

Generally produced by endocrine glands
- Some may be produced by specialized cells
Ex) GI, kidneys, WBCs

Question 7

Hormones Produced by the GI System

Answer 7

Gastrin, enterogastrone, secretin, & cholecystokinin

Question 8

Hormones Produced by the Kidneys

Answer 8

Erythropoietin: Stimulates bone marrow for RBC production

Question 9

Hormones Produced by the WBCs

Answer 9

Cytokines (hormone-like proteins)

Question 10

Function & Regulation of Hormones

Answer 10

Rapid action of the nervous system is balanced by slower action of hormones
- Permits precise control of organ functions in response to changes w/in & outside the body

Endocrine glands are composed of acini
- Rich blood supply allows for hormones produced by endocrine glands to quickly enter the bloodstream quickly
-> Amount depends on unique function & body’s needs

Negative feedback system prevents overaccumulation of hormones

Question 11

Acini

Answer 11

Secretory cells arranged in minute clusters

Question 12

Negative Feedback

Answer 12

Regulating mechanism where an increase or decrease in hormone levels decreases or increases organ function producing the substance

When hormone concentration increases-> further production decreases

When hormone concentration decreases-> production increases

Question 13

What are the 4 classifications of hormones?

Answer 13

1) Amines & amino acids: epinephrine, norepinephrine, & thyroid hormones

2) Peptides, polypeptides, proteins, & glycoproteins: Thyrotropin-releasing hormone {TRH}, FSH, GH

3) Steroids: Corticosteroids (hormones prod by adrenal cortex)

4) Fatty acid derivatives: Eicosanoid, retinoids

Question 14

Paracrine Action

Answer 14

Hormones that NEVER enter the bloodstream & act locally in area where they are released
Ex) Sex hormones secreted via ovaries

Question 15

Autocrine Action

Answer 15

Hormones may act on actual cells from where they are released
Ex) Effect on insulin from pancreatic beta cells on those cells

Question 16

Action of Peptide & Protein Hormones

Answer 16

Hormones can alter the function of the target tissue via interacting w/ chemical receptors located on either side of the cell membrane/ interior

Ex) Cyclic AMP
1) Peptide & protein hormones interact w/ receptor sites on cell surface

2) Stimulation of the intracellular enzyme adenyl cyclase

3) Increased production of cyclic AMP (3’, 5’-adenosine monophosphate) inside the cell
- Alters enzyme activity
- 2nd messenger that bonds the peptide hormone at cell surface to change in intracellular environment

Can also act by changing membrane permeability & act w/in secs or mins

Question 17

Amine Hormones Mechanism of Action

Answer 17

Similar to peptide hormones

Question 18

Steroid Hormones Mechanism of Action

Answer 18

Penetrate cell membranes & interact w/intracellular receptors
- Due to smaller size & high lipid solubility

Steroid-receptor complex modifies cell metabolism & formation of mRNA & DNA
- mRNA stims protein synthesis w/in the cell

Req several hrs to exert their effects
Why? They exert their action via modification of protein synthesis

Question 19

Endocrine Assessment: Health History

Answer 19

Ask about duration, severity, how these changes affect ADLs and self perception, and family history

Ask if they have experienced following changes:
Energy level
Tolerance to heat or cold
Weight
Thirst
Urination frequency
Bowel function
Body proportions
Muscle mass
Fat & fluid distribution
2ndary sexual characteristics (hair loss)
Menstrual cycle
Memory
Concentration
Sleep patterns
Mood
Vision
Joint pain
Sexual dysfunction

Question 20

Endocrine Assessment: Physical

Answer 20

Should include: VS, head-to-toe exam, palpation of skin, hair, & thyroid

Compare findings w/ previous finding, if applicable

Note physical, psychological, & behavioral alterations

Changes in Physical Characteristics:
- Growth of facial hair in women
- “Moon face”
- “Buffalo hump”
- Exophthalmos, vision changes
- Edema
- Thinning of the skin
- Obesity of the trunk
- Extremity thinness
- Increased size of hands & feet
- Edema
- Hyper/or hyporeflexia

Question 21

Exophthalmos

Answer 21

Abnormal protrusion of one or both eyeballs

Question 22

Mood & Behavior Changes

Answer 22

Nervousness, lethargy, & fatigue

Question 23

Diagnostic Evaluation: Blood Tests

Answer 23

Determine the levels of circulating hormones, presence of autoantibodies, and effect of specific hormones on other substances
Ex) Effect of insulin of blood glucose levels

Serum levels of hormones help determine presence of hypo-/hyperfunction of endocrine system & site of dysfunction

Radioimmunoassay tests: Detect antigen levels

Question 24

Diagnostic Evaluation: Urine Tests

Answer 24

Used to measure the amount of hormones/ end products of hormones excreted by the kidneys

1-time/ 24-hr specimens are collected to measure hormones or metabolites
Ex) Urinary levels free of catecholamines (norepinephrine, epinephrine, & dopamine) for pts w/suspected pheochromocytoma

Disadvantages: Pts may be unable to urinate at scheduled intervals
- Some meds/diseases may affect the test results

Question 25

Pheochromocytoma

Answer 25

Tumor of the adrenal medulla

Question 26

Diagnostic Evaluation: Stimulation Tests

Answer 26

Used to determine hypofunction of an endocrine organ

Question 27

Diagnostic Evaluation: Suppression Tests

Question 28

Diagnostic Evaluation: Imaging

Question 29

Diagnostic Evaluation: Genetic Screening