Renal and Endocrine Flashcards
How does the angiotensin system work?
Blood pressure or fluid volume drops
Renin is released from kidneys which turns angiotensin to angiotensin I
ACE is released from the lungs which converts angiotensin I to angiotensin II (vasoconstrictor)
Angiotensin II acts on the adrenal gland to release aldosterone
Aldosterone acts on the kidneys to reabsorb salt and water which increases fluid volume and blood pressure
List 7 types of medication that treat hypertension
Central adrenergic medications Peripheral adrenergic inhibitors Arteriolar dilators Calcium channel blockers B-adrenergic blocking agents Diuretics Angiotensin-converting enzymes (ACE) Angiotensin-receptor antagonists (ARBs)
What does ABCDE stand for?
Ace inhibitors, angiotensin II receptor antagonists and alpha antagonists Beta blockers Calcium channel blockers Diuretics Endothelin receptor agonists
How do ACE inhibitors work?
They prevent angiotensin I turning into angiotensin II which is a powerful vasoconstrictor resulting in reduced peripheral vascular resistance and subsequently BP
Which suffix indicates ACE inhibitors?
Pril
What’s an ARB?
Angiotensin-receptor antagonist
What suffix indicates an ARB?
Sartan
How do ARBs work?
Antagonise angiotensin II receptors on vascular smooth muscles which increases renal blood flow and maintains or increases glomerular filtration rate while decreasing renal vascular resistance
ARBs indications
Hypertension in patients who are unable to tolerate ACEIs
ARBs interactions
Potassium sparing diuretics, NSAIDs
ARBs nursing considerations
Sodium or intravascular volume depletion should be corrected before therapy. Monitor serum creatinine and potassium
Which suffix indicates Alpha antagonists?
ocin
How do Alpha antagonists work?
They block the alpha receptors located on the arterioles and venules. These receptors mediate the peripheral vasoconstrictive response. Therefore the blockade lowers systemic vascular resistance
Alpha antagonist nursing considerations
Dose should start small and increase gradually to minimise risk of first dose hypotension. Advise patients to get up slowly to avoid orthostatic hypotension
Which electrolyte allows the kidneys to regulate fluid?
Sodium
Define preload
Initial stretching of the cardiac muscle cells prior to contraction which allows ventricular filling
Define afterload
The force or load against which the heart has to contract to eject blood from the heart
What are the three main types of diuretics?
Thiazide, High ceiling loop, Potassium-sparing
How do Thiazide diuretics work?
They increase the excretion of sodium and chloride ions and water in the proximal segment of the distal tubule
Thiazide diuretics indication
Primary therapy of hypertension in those above 65. Mild to moderate stable heart failure
What side effect is common across all diuretics?
Electrolyte imbalance
How do High-ceiling loop diuretics work?
They inhibit sodium and chloride reabsorption in the proximal and distal tubules especially in the ascending loop of Henle which leads to greater water excretion
How do Potassium-sparing diuretics work?
Aldosterone antagonists that inhibit in the distal convoluted distal tubule that increases the excretion of sodium and water but decreases potassium excretion
What’s BPH?
Benign Prostatic Hypertrophy. Enlarged prostate
Which two drugs are used to treat BPH?
a-adrenergic receptor blockers
5-a-reductase inhibitors
How do a-adrenergic receptor blockers work?
They’re selective alpha adrenoceptor antagonists that decreases urethral pressure resulting in decreased resistance to urine flow during voiding
How does Sodium Citrotartrate (Ural) work?
Alkalises the urine to decrease pain experienced with more acidic urine
Which kind of drugs is typically prescribed to resolve UTIs?
Antibacterial antibiotics
What are the two ways that insulin is naturally introduced into the bloodstream?
Low basal release via the capillaries into the portal circulation to the liver and bolus release in response to stimuli (glucose absorbed from oral intake)
Where is excess glucose stored in the body in the form of glycogen or adipose tissue?
Liver or muscles
What does insulin do?
Converts glucose to glycogen
What’s the difference between Diabetes 1 and 2?
Type 1 means the pancreas fails to produce insulin. Type 2 means that cells fail to respond appropriately to insulin
What 3 aspects are important to know in relation to the effectiveness of insulin administration?
Onset, Peak, Duration
What are OHAs?
Oral hypoglycaemic agents
What are the common actions of OHAs?
Simulate further insulin release Lower insulin resistance Sensitise cells to the action of insulin Reduce glucose load Enhance function of incretins Alter absorption of carbohydrates
What class is Metformin?
Biguanide (insulin sensitizer)
How does Metformin work?
Decreases hepatic glucose production and intestinal absorption of glucose and improves insulin sensitivity
Metformin nursing considerations
Monitor blood glucose levels and renal impairment
How do Thiazolidinediones work?
They lower blood glucose level by decreasing insulin resistance and improve sensitivity to insulin in muscle and adipose tissue
How do Sulfonylureas work?
They stimulate insulin release from functioning pancreatic cells. Improve sensitivity of beta cells to glucose stimulus and reduce basal glucose production by the liver
How do Dipeptidyl Peptidase 4 inhibitors work?
The enhance the level of incretin hormones which are responsible for regulation of glucose homeostasis
How does Thyroxine work?
Hormone replacement drug that has a slow onset of action of roughly a week. Treats Hypothyroidism
What is Addison’s Disease?
A disorder in which the adrenal gland doesn’t produce enough aldosterone and cortisol
What drug treats Addison’s Disease?
Hydrocortisone. It replaces Cortisol
What is Cushing’s Syndrome?
Opposite of Addison’s Disease. Meaning the adrenal gland produces too much cortisol and aldosterone. Brought on by excessive administration of corticosteroids
