objective 2.6 (1) Flashcards
Responsible for the regulation and elimination of body fluids
urinary system
what is the urinary system composed of?
kidneys, ureters, bladder and urethra
functional unit of the kidney
nephron
filter the bloodstream, removing waste products, water and electrolytes
kidneys
iltration of plasma by the glomerulus;
filtered substances include water, sodium, chloride,
bicarbonate, potassium, glucose, urea, creatinine and uric acid
glomerular filtration
iltrate enters Bowman’s capsule and
then moves through the tubular system of the nephron and is
either reabsorbed into the systemic circulation or excreted as
urine
tubular reabsorption
formed urine drains from the collecting
tubules, into the renal pelvis and down the ureters to the
bladder
tubular secreation
what are the functions of the kidneys?
Urine formation
Excretion of waste products
regulation of electrolytes
regulation of acid-base balance
control of water balance
control of blood pressure
regulation of red blood cell production (erythropoetin)
synthesis of vitamin D to active form
secretion of prostaglandins
regulates calcium and phosphorus balance
activates growth hormone
Measures the amount
of urea in blood
blood urea nitrogen
is cleared from the blood and excreted by
the kidneys
urea
what can urea be affected by?
protein breakdown,
dehydration, overhydration and liver failure, so it is
not an infallible test of kidney function
he waste product of creatinine phosphate, a
high-energy compound found in skeletal muscle tissue
creatinine
evaluates renal function by evaluating
damage to nephrons
serum creatinine
Used as an
indication of the glomerular filtration rate (GFR)
creatinine clearance test
what is the normal creatinine?
125ml/min
measurement of the
concentration of urine as compared to water
urine osmolality
measures amount of uric acid in
blood (as in gout)
uric acid level
urine color should be…?
yellow
clarity should be…?
clear
Defined as a drug that increases the excretion of urine
(water, electrolytes and waste products) by the kidneys
Mainstay of therapy for the treatment of hypertension and
heart failure and for prevention of kidney damage during
acute kidney injury
diuretics
what are the types of the diuretics?
- Carbonic anhydrase inhibitors
- Loop diuretics
- Osmotic Diuretics
- Potassium sparing diuretics
- Thiazides and related diuretics
what is the MOA of carbonic anhydrate inhibitors?
inhibit carbonic anhydrase which causes the excretion of sodium,
potassium bicarbonate, and water
They are sulfanomides with non-bacteriostatic action
what are the indications of carbonic anhydrase inhibitors?
Adjunct drugs in the long-term management of open-angle glaucoma
and adjunct therapy for secondary glaucoma
Used with miotics to lower intraocular pressure before ocular surgery in
certain cases
what are the contraindications of carbonic anhydrase inhibitors?
Known drug allergy, Hyponatremia, Hypokalemia, Severe kidney or liver
dysfunction, Adrenal gland insufficiency, Cirrhosis
what are the AE of carbonic anhydrase inhibitors?
Acidosis, Hypokalemia, Drowsiness, Anorexia, Paresthesias, Hematuria,
Urticaria, Photosensitivity, Melena (blood in the stool)
what are the interactions of carbonic anhydrase inhibitors?
An increase in digoxin toxicity may occur when they are combined with
digoxin.
Can cause hypokalemia, and use with corticosteroids may also cause
hypokalemia.
Increased effects of amphetamines, carbamazepine, cyclosporine, phenytoin,
and quinidine sulphate with concurrent use of carbonic anhydrase inhibitors
what is the MOA of loop diuretics?
nhibiting the reabsorption of sodium and chloride ions
in the distal and proximal tubules.
Used to manage edema
Increases the dilation of blood vessels and reduced kidney,
pulmonary, and systemic vascular resistance
what are the intended effects and side effects of loop diuretics?
Intended Effects:
* Urine output is increase, Urine is lighter in color, Blood pressure is
lower
Side Effects:
* dizziness, light-headedness, postural hypotension, hypokalemia,
hyponatremia
what is the MOA of osmotic diuretics?
increases the density of the filtrate in the glomerulus which
prevents the reabsorption of water which allows the water to be
excreted.
what are the AE of osmotic diuretics?
Convulsions, Thrombophlebitis, Pulmonary congestion
Other: headaches, chest pains, tachycardia, blurred vision,
chills, and fever
what is the MOA of potassium-sparing diuretics?
Increase sodium and water excretion; depress the
excretion of potassium
what are the indications of potassium-sparing diuretics?
- Hyperaldosteronism
- Hypertension
- Reversing potassium loss caused by potassium-wasting diuretics
- Certain cases of heart failure: prevention of remodelling
Antagonist to aldosterone, a hormone produced by
the adrenals which enhances the reabsorption of
sodium; blocking of this action causes and increase in
sodium excretion but not potassium; pg. 492 Drug
profile.
Often prescribed for children with heart failure.
can cause gynecomastia,
amenorrhea and irregular menses and
postmenopausal bleeding.
spironolactone
what are the AE of potassium-sparing diuretics?
- Central nervous system: Dizziness, headache
- Gastrointestinal: Cramps, nausea, vomiting, diarrhea
- Other: Urinary frequency,
weakness, hyperkalemia
what is the MOA and indications of thiazide and thiazide-like diuretics?
MOA: Inhibit tubular resorption of sodium, chloride, and potassium ions
Results in decreased extracellular fluid volume though increased fluid excretion.,
Dilate the arterioles by direct relaxation, Decrease preload and afterload
INDICATIONS
Hypertension (one of the most prescribed group of drugs for this),
Edema
Heart Failure
what are the AE of thiazide/like diuretics?
Dizziness, headache, blurred vision, GI disturbances, Erectile dysfunction, Jaundice,
Urticaria, photosensitivity, Hypokalemia, glycosuria, hyperglycemia, hyperuricemia,
hypochloremic alkalosis
