Urinary And Renal Medications Flashcards
Location of the kidneys
Bean shaped organs located along the posterior abdominal wall,protected by the ribs and back muscles
Renal trauma may result in bleeding with the kidney which may be detected as blood in the urine (Haematuria). Patients will be treated for the cause of the trauma and this often involves the provision of iv fluids. (can be administered to restore the body’s fluid and electrolyte balance.
Blood flow within the kidneys
Blood enters the kidneys through the renal arteries and leaves via the renal veins. It is important to remember the vessels supplying blood to the kidneys can be affected by disease like any other vessels in the circulatory system.
Renal physiology
Nephrons are the functional units of the kidney; they consist of a renal corpuscle (glomerulus plus glomerular capsule) and renal tubule (proximal convoluted tubule, nephron loop, distal convoluted tubule)
The filtrate is modified in the renal tubules and collecting ducts into urine: during these processes, substances may be completed reabsorbed, regulated or eliminated
Fluid and electrolyte homeostasis for bodily functions
Fluids move between the intracellular and extracellular compartments (e.g. by osmosis) to maintain homeostatic levels of fluids necessary for bodily functions
The body maintains major electrolytes within homeostatic levels; these include sodium, potassium and chloride
Fluid and electrolytes are regulated by four main hormones with the renal system: angiotensin II, antidiuretic hormone (ADH), aldosterone (ALDO) and atrial natriuretic peptide hormone (ANP)
Urine
Urine is formed in the kidneys and is comprised of water, ions, nitrogenous waste products and some hormones
The characteristics of urine include volume, pH, specific gravity, colour, and smell
Some diseases impact kidney functioning and are detected or monitored by assessing urine e.g. detecting glucose in the urine may indicate undiagnosed or poorly controlled diabetes. In such cases, treatment will be initiated for the primary disease however there may also be a need to administer medications to improve urinary/renal functioning.
Renal stenosis
Definition
Arteries that supply the kidneys become hardened and narrow
Processes at play
Atherosclerosis - Lesions form in the arteries which cause narrowing and loss of elasticity.
Hypercholesterolaemia - High cholesterol in the blood (lesions in the arteries are made of cholesterol and lipids and collagen).
Hypertension - High blood pressure when the pressure in arteries is constantly high and puts strain on the system.
Acute kidney injury (AKI)
Definition
AKI previously called acute renal failure (ARF)
A sudden decrease in kidney function (develops within hours or days). AKI is identified by physiologic changes e.g. decreased urine output or increased serum creatinine.
Processes at play
Pre-renal - Decreased glomerular filtration rate due to decreased kidney blood flow.
Intrinsic - Injury or damage to kidney which results in reduced elimination and build up of products usually eliminated by kidney e.g. urea and creatinine.
Post-renal - Disorders that impact the urinary tract after the kidney (e.g. narrowed urethra, enlarged prostate, bladder cancer). This urinary tract obstruction can lead to urine backing up and causing the kidney to swell (hydronephrosis) and become damaged.
Chronic kidney injury (CKI)
Definition
CKI previously called chronic renal failure (CRF)
A gradual decrease in kidney function (develops over months or years) CKI identified by physiologic changes e.g. increased serum creatinine.
Processes at play
May result from other disease processes e.g. Hypercholesterolaemia, hypertension, diabetes
- Poorly managed diabetes may result in increased blood glucose, narrowed kidney blood vessels and kidney damage.
Renal calculi
Definition
Hard deposits made of minerals and salts that form inside the kidneys (kidney stones) and may travel down the urinary tract
Processes at play
Decreased urine volume or urinary stasis - Solutes crystallise out of the urine and form stones.
Increased excretion of stone forming components e.g. calcium, uric acid, struvite stones
Hyperparathyroidism, or an overactive parathyroid, may lead to high blood calcium levels, increased excretion of calcium and the development of calcium stones
Gout or acidic urine (low pH) may lead to increased excretion of uric acid and the development of uric acid stones
Infections by microorganisms (e.g. pseudomonas) may lead to increased ammonia and the development of struvite stones.
Urinary tract infection
Definition
An infection in any part of the urinary system (kidneys, ureters, bladder and urethra).
Processes at play
Urinary stasis - Urine may stay in the bladder for a prolonged period and this promotes bacterial growth.
What is diuretics?
Diuretic medications promote water loss from the body into urine
Loop diuretics
Medication examples: Generic (Trade) name
Furosemide (Frusemide)
Ethacrynic acid
Action
Act to promote water loss from the body. Inhibit the reabsorption of sodium, chloride and potassium ions, along with water, in the Loop of Henle.
Useful in the treatment of oedema e.g. renal and cardiac disease and hypertension.
Nursing responsibilities / Patient education
Nursing responsibilities:
Monitor blood pressure before and after medication (may cause hypotension).
Monitor fluid balance, electrolytes and kidney function (may cause hypokalaemia, dehydration and kidney failure).
Monitor for cardiac dysrhythmias due to hypokalaemia (low potassium).
Patients should be advised to:
Take their diuretic in the morning to avoid urinary frequency overnight. If more than one dose is required per day, take last dose at least six hours before bed (usually no later than 4pm).
Take potassium supplements (e.g. Span-K) as ordered as the diuretic is depletes potassium.
Thiazide diuretics
Medication examples: Generic (Trade) name
Hydrochlorothiazide (Dithiazide)
Indapamide (Natrilix)
Action
Act to promote water loss from the body. Inhibit the sodium-chloride reabsorption from the distal tubules of the nephron. May impact upon calcium transport.
Useful in the treatment of oedema and hypertension. Use with caution in those predisposed to gout (may cause blood uric acid to rise).
Nursing responsibilities / Patient education
Nursing responsibilities:
Monitor blood pressure before and after medication (may cause hypotension).
Monitor fluid balance, electrolytes and kidney function (may cause dehydration and kidney failure).
Avoid use in those with sulfonamide sensitivity.
Patients should be advised to:
Take their diuretic in the morning to avoid urinary frequency overnight. If more than one dose is required per day, take last dose at least six hours before bed (usually no later than 4pm).
Get up slowly to avoid postural hypotension and dizziness.
Potassium sparing diuretics: Aldosterone antagonists
Medication examples: Generic (Trade) name
Spironolactone (Aldactone)
Action
Act to promote water loss from the body however are less effective than other diuretics.
Inhibit the action of aldosterone in the distal tubules of the nephron.
Nursing responsibilities / Patient education
Nursing responsibilities:
Monitor blood pressure before and after medication (may cause hypotension).
Monitor fluid balance, electrolytes and kidney function (may cause dehydration and kidney failure).
Patients should be advised to:
Take their diuretic in the morning to avoid urinary frequency overnight.
Diuretics are used to treat?
Hypertension (High blood pressure)
