Chapter 26- Diuretic Drugs Flashcards
Afferent arterioles
The small blood vessels branching from the renal artery approaching the glomerulus (proximal part of the nephron).
Aldosterone
A mineralocorticoid steroid hormone produced by the adrenal cortex that mediates the actions of the renal tubule in the regulation of sodium and potassium balance in the blood.
Ascites
An abnormal intraperitoneal accumulation of fluid (defined as a volume of 500mL or greater) containing large amounts of protein and electrolytes.
Collecting duct
The most distal part of the nephron between the distal convoluted tubule and the ureters, which lead to the urinary bladder.
Distal convoluted tubule
The part of the nephron immediately distal to the ascending loop of Henle and proximal to the collecting duct.
Diuretics
Drugs or other substances that tend to promote the formation and excretion of urine.
Direct arteriolar dilation, decreasing peripheral vascular resistance. Reduce: extracellular fluid volume, plasma volume, and cardiac output.
Efferent arterioles
The small blood vessels exiting the glomerulus. At this point, blood has completed its filtration in the glomerulus.
Filtrate
The material that passes through a filter. In the kidney, the filter is the glomerulus, and the filtrate is the extracted material from the blood (normally liquid) that ultimately becomes urine.
Glomerular capsule
The open, rounded, and most proximal part of the proximal convoluted tubule that surrounds the glomerulus and receives the filtrate from the blood.
Glomerular filtration rate (GFR)
The volume of ultrafiltrate extracted per unit of time from the plasma following through the glomeruli of the kidney. .
Glomerulus
The cluster of kidney capillaries that marks the beginning of the nephron and is immediately proximal to the proximal convoluted tubule.
Loop of Henle
The part of the nephron that is immediately distal to the proximal convoluted tubule.
Nephron
The microscopic functional filtration unit of the kidney, consisting of (in anatomical order from proximal to distal) the glomerulus, proximal convoluted tubule, loop of Henle. distal convoluted tubule, and the collecting duct, which empties urine into the ureters. There are approximately one million nephrons in each kidney.
Open-angle glaucoma
Elevated pressure in an eye because of obstruction of the outflow of aqueous humour, but access to the trabecular meshwork remains open.
Proximal convoluted tubule
The part of the nephron that is immediately distal to the glomerulus and proximal to the loop of Henile.
Ultrafiltration
Filtration at a microscopic level; the term is often used to describe the filtration function of the kidneys, with the filtrate referred to more specifically as ultra filtrate.
Sodium
In the nephron, where sodium goes, water follows.
If water is not absorbed, it is excreted as urine.
Carbonic Anhydrase Inhibitors (CAIs) Mech of Action
ex) Acetazolamide (Acetazolam), Methazolamide.
Management of Ph. Reduces H+ ion concentratoin in renal tubules. Resorption of water is decreased and urine volume is increased.
CAIs Indications
Open-Angle Glaucoma
Used with motics to lower intraocular pressure before ocular surgery in certain cases.
Also used in treatment of: Edema, Epilepsy, High-altitude sickness.
The metabolic acidosis they induce reduces their diuretic effect in 2-4 days.
CAIs Contraindications
Drug allergy, Hypoatremia, Hypokalemia, severe Kidney for liver dysfunction, cirrhosis
CAIs Adverse Effects
Metabolic acidosis, anorexoa, hypokalemia, drowsiness, paraesthesias, urticaria
CAIs Interactions
Digitalis, Corticosteroids, oral hypoglycaemic drugs and quindine
Loop diuretics Mech of Action
Common in Hospitals.
Ex) Furosemide (Lasix)- can be given IV
Act directly on the ascending limb of the loop of Henle to inhibit chloride and sodium resorption. Resulting in the dilation of blood vessels and reduced peripheral vascular resistance.
Loop diuretics Drug effects
Potent diuresis.
Potassium and sodium depletion. (Especially Potassium)
Loop Diuretics Indications
Edema, hypertension, hypercalcemia, certain cases of heart failure.
Loop Diuretics Contraindications
Allergy to sulfonamide antibiotics, severe electrolyte loss
Loop Diuretics Adverse Effects
Dizziness, N/V/D, Hypokalemia
Osmotic Diuretics Mech of Action
Ex) Mannitol (Osmitrol).- IV only, use a filter
Work mostly in the proximal tubule.
Osmotic Diuretics Indications
Reduction of intracranial pressure
Treatment of cerebral edema
Osmotic Diuretic Contraindications
Severe Kidney Disease, Pulmonary edema
Osmotic Diuretic Adverse Effects
Convulsions, Thrombophlebitis, Pulmonary congestion, Headaches
Potassium-Sparing Diuretics Mech of Action
Ex) Spironolactone(Aldactone). Does not have same decrease in potassium.
Work in collecting ducts and distal convoluted tubules.
Block the resorption of sodium and water. Do not affect potassium. Prevent potassium from being pumped into the tubule, thus preventing its secretion.
Potassium-Sparing Diuretics Indications
Spironolactone (Aldactone)-Hypertension.
Amiloride (Midamor)-Treatment of heart failure
Potassium-Sparing Diuretics Contraindications
Hyperkalemia. Severe kidney failure or anuria
Potassium-Sparing Diuretics Adverse Effects
Hyperkalemia, Gynecomastia, Amenorrhea, Irregular menses, postmenopausal bleeding.
Potassium-Sparing Diuretics Interactions
Lithium, ACE inhibitors, Potassium supplments
Thiazide and Thiazide like Diuretics Mech of Action
Ex) Hydrochlorothiazide.
Inhibit tubular resorption of sodium, chloride, and potassium ions. Dilate arterioles by direct relaxation.
Lowered peripheral vascular resistance.
Depletion of sodium and water (and potassium)
Thiazide…..Indications
Hypertension, Edematous, Heart failure, and as an adjunct drugs in treatment of edema and hepatic cirrhosis.
Thiazide….Contraindications
Anuria (failure of kidneys to produce urine), Severe Kidney Failure.
Thiazide….adverse effects
Impotence, Hypokalemia, Glycosuria, Hyperglycemia, hyperuricemia
Diuretic Drugs Nursing Implications
PT history and physical exam.
Assess baseline fluid volume status (Edema)
Bloodwork.
Instruct PT to take in the morning as much as possible to avoid interference with sleep patterns.
Maintain proper nutritional and fluid volume status.
Eat more potassium-rich foods when taking but with the potassium-sparing drugs.
Monitor blood glucose levels
Teach PTs to change positions slowly, keep log of their weight, encourage PTs to return to F/U visits and lab tests.
Puts who have been ill need to notify Doc.
S&S of hypokalemia: Muscle weakness, constipation, irregular pulse rate, overall feeling of lethargy.
Excessive consumption of liquorice can lead to additive hypokalemia in PTs taking Thiazides.
Montior for Adverse and Therapeutic effects.
