Renal Disorders Flashcards
What are the two types of renal failure?
Acute and Chronic
What is the purpose of treatment in end stage renal failure?
To maintain homeostasis
List three treatments for renal failure.
- Continuous Ambulatory Peritoneal Dialysis (CAPD)
- Haemodialysis
- Renal transplant
What is CAPD?
Continuous Ambulatory Peritoneal Dialysis
What is required for a kidney transplant?
A suitable donor with matching tissues and blood group
Where is the third kidney transplanted during a renal transplant?
In the abdominal cavity
What medications are needed after a renal transplant?
Immunosuppressive medication such as prednisone and cyclosporine
What is the access method for haemodialysis?
A-V fistula or Silastic Catheter
How often is haemodialysis typically performed?
3 times per week, 6-10 hours each session
How long does CAPD treatment take daily?
4 times per day
What is the average time commitment for kidney transplant post-operative care?
Minimal time commitment
What equipment is used for haemodialysis?
Dialysis machine
What is the primary pain associated with haemodialysis?
Needles
What is the typical hemoglobin level for patients on haemodialysis?
7-8g
What metabolic control is required for patients on haemodialysis?
Variable diet required
What dietary intervention is needed for patients on dialysis regarding sodium?
Decreased sodium intake
What is the most strictly controlled electrolyte in patients with chronic kidney disease?
Potassium
What are the risks of high potassium levels in the body?
Can cause cardiac arrest
What nutrient deficiency can lead to fluid retention in end stage kidney disease?
Protein
Which vitamins may patients with end stage kidney disease need to supplement?
- Vitamin B
- Vitamin C
What happens to phosphate levels when kidneys fail?
Phosphate levels increase and bind calcium, leading to decreased calcium levels
What are Chvostek’s and Trousseau’s signs associated with?
Hypocalcemia
What is a consequence of elevated uric acid in chronic kidney disease?
Kidney stones or gout
What causes metabolic acidosis in renal failure?
Less excretion of H+
True or False: Infections are seldom a problem with CAPD.
True
Fill in the blank: Patients with chronic kidney disease should have _______ fluid intake.
Decreased
What dietary adjustment is needed for potassium in patients on dialysis?
Decreased potassium intake
What are the signs of hypocalcemia?
- Increased capillary permeability
- Neuromuscular excitability
- Decreased blood coagulation
What is the effect of high urea levels on vitamin D?
Suppresses vitamin D action in the gut
What are the symptoms of uremia?
- Nausea
- Vomiting
- Fatigue
- Neuropathy
What is the mean hospital time for patients on haemodialysis?
1 week/year
What is a common complication of immunosuppressive therapy after a kidney transplant?
Infection
What is the normal composition of urine?
Clear, amber coloured fluid, 95% water, 5% dissolved solids, contains metabolic wastes, should not contain protein, blood cells, or glucose.
What does urine specific gravity indicate?
The kidneys’ ability to concentrate urine.
What does proteinuria and microalbuminuria indicate?
Abnormal filtering or defects in reabsorption.
How can Glomerular Filtration Rate (GFR) be calculated?
Using 24 hr urine samples.
What happens to Blood Urea Nitrogen (BUN) if the GFR rate decreases?
BUN increases due to the kidneys being unable to effectively clear nitrogenous waste products from the blood.
What is the relationship between plasma creatinine and renal function?
An increase in plasma creatinine indicates poor renal function and decreased eGFR.
Define GFR (glomerular filtration rate).
Volume of fluid filtered from the glomerular capillaries into the Bowman’s capsule per unit time.
What is the formula for calculating GFR?
GFR = Urine concentration x Urine flow / Plasma concentration.
What is the most accurate method for measuring GFR?
Injecting an inert polysaccharide, inulin, into the bloodstream.
What is the normal range of GFR adjusted for body surface area?
100-130 ml/min/1.73m2.
What is eGFR?
Estimated GFR calculated from serum creatinine level.
What is the significance of patient muscularity in eGFR calculations?
It affects the prediction of the 24-hour creatinine excretion rate.
What formula is used in New Zealand for eGFR?
Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) formula.
What is the eGFR calculation for females with Cr ≤62?
eGFR (ml/min) = 144 x [Cr(µmol/L)/0.7]-0.329 x [0.993]Age.
What is the eGFR calculation for males with Cr >80?
eGFR (ml/min) = 141 x [Cr(µmol/L)/0.9]-1.209 x [0.993]Age.
What should be considered when interpreting eGFR results?
Caution in non-Caucasians, extremes of body weight, pregnancy, and low creatinine.
What is a common reason for patients to present with renal disease?
Abnormality on routine blood test or urinalysis.
What does a sudden reduction in eGFR indicate?
Acute kidney injury (AKI).
What does a reduction in eGFR over 3 months indicate?
Chronic kidney disease (CKD) and staging is commenced.
What is the implication of a normal GFR?
It doesn’t rule out renal disease.
Fill in the blank: Renal insufficiency is typified by _______.
build-up of waste products & inability to concentrate or dilute urine.
What is Acute Kidney Injury (AKI)?
An abrupt decrease or cessation of glomerular filtration rate or kidneys stop working. It is reversible with correct and prompt treatment.
What is Chronic Kidney Disease (CKD)?
A progressive and irreversible decline in glomerular filtration rate.
What is Renal Failure?
A decrease or cessation of glomerular filtration to the extent that the kidneys can no longer support the body’s needs.
Name a common cause of Chronic Kidney Disease.
- Diabetes
- Hypertension
- Obstructive nephropathy
- Kidney disease (chronic glomerulonephritis, pyelonephritis, polycystic kidney disease)
- Renal artery stenosis
- Lead poisoning
- Fatty plaque deposits (atherosclerosis in kidney artery)
What are the three groups of causes for Chronic Kidney Disease?
- Pre-renal: shock, ischaemia
- Renal: direct damage to nephrons due to infection or nephrotoxic injury
- Post-renal: obstruction of ureters or blockage in the ureters
How does chronic hypertension affect kidney function?
Elevated pressure damages blood vessels leading to inflammation, thickening of arterial walls, and renal ischemia.
What happens to GFR below arterial blood pressures of 80?
GFR decreases.
What are the stages of Chronic Kidney Disease?
- Diminished renal reserve: no signs and symptoms
- Renal insufficiency: waste products build up, inability to concentrate or dilute urine (75% or more nephrons lost)
- End stage: oliguria present, waste products build up, treatment required (90% or more nephrons lost)
What is the prevalence of Stage 3 CKD in New Zealand?
8.7% of the population.
What are common risk factors for CKD in New Zealand?
- Age 50+ years
- Diabetes
- High blood pressure
- Smoking
- Obesity
- Family history of kidney disease
- Maori/Pacifika
What percentage of patients starting dialysis have diabetes?
50%.
What is Rhabdomyolysis?
Significant muscle damage that releases muscle cell components like myoglobin into the bloodstream, causing electrolyte imbalances and potential kidney damage.
How does chronic analgesic nephropathy occur?
NSAIDs inhibit cyclooxygenases, leading to decreased blood flow and damage in the kidney.
What type of genetic disease is Polycystic kidney disease (PKD)?
Usually autosomal dominant.
What happens in full-blown Polycystic kidney disease?
Multiple fluid-filled cysts grow out of nephrons, leading to reduced kidney function and eventual kidney failure.
How does an enlarged prostate affect urine flow?
It squeezes the urethra, blocking the flow of urine, which can lead to high pressure in the bladder and kidney damage.
True or False: CKD is highly associated with cardiovascular disease.
True.
Fill in the blank: CKD is characterized by a _____ decline in glomerular filtration rate.
progressive and irreversible
Define Acute Kidney Injury (AKI)
An abrupt decrease or cessation of glomerular filtration rate or kidneys stop working
AKI is reversible if the patient receives correct and prompt treatment.
What is Chronic Kidney Disease (CKD)?
A progressive and irreversible decline in glomerular filtration rate.
What is Renal Failure?
A decrease or cessation of glomerular filtration to the extent that the kidneys can no longer support the body’s needs.
What are the types of kidney injury?
- Pre-renal
- Renal
- Post-renal
What are the characteristics of Pre-renal kidney injury?
Mostly associated with lack of blood supply or low blood pressure.
What does Renal kidney injury affect?
Affects the nephrons directly.
What causes Post-renal kidney injury?
Mostly due to back pressure from obstructions.
List some causes of Acute Kidney Injury.
- Complications of surgery
- Severe burns
- Trauma
- Renal ischaemia
- Drugs (e.g., antibiotics, NSAIDs)
- Toxins (e.g., heavy metals, alcohol)
- Heatstroke
- Multiple organ failure
- Sepsis
- Obstructed urine flow
- Kidney stones
- Acute pyelonephritis
What factors contribute to the formation of Kidney stones?
- Diet
- Low fluid intake
- Urinary tract infections (UTIs)
- Genetics
What is Pyelonephritis?
A bacterial infection in the kidney, either from an ascending UTI or via the bloodstream.
What are the symptoms of Pyelonephritis?
- Fever
- Pain
- Nausea
What occurs during the ONSET phase of Acute Kidney Injury?
Time from precipitating event until tubular damage occurs, lasting hours or days.
Describe the OLIGURIC phase of Acute Kidney Injury.
Decreased urine output, severe deficiency leading to ANURIA, and lasts 8-14 days or longer.
What happens during the DIURETIC phase of Acute Kidney Injury?
Filtration increases but absorption is impaired; GFR and urine output increase.
What characterizes the RECOVERY phase of Acute Kidney Injury?
Gradual return to normal functioning, including normalisation of fluid and electrolyte balance.
What is the first line of treatment for Acute Kidney Injury?
Remove the cause, stop nephrotoxic drugs, and provide IV fluids.
Fill in the blank: Pre-renal causes of kidney injury are mostly due to _______.
low blood flow in the renal arteries.
True or False: Acute Kidney Injury is irreversible.
False
What are the five major functions of the kidney?
- Removal of water and wastes from the blood
- Maintains electrolyte balance
- Maintains acid-base balance
- Regulates blood pressure by renin secretion
- Stimulates production of red blood cells by erythropoietin secretion
Erythropoietin is a hormone produced by the kidneys that stimulates red blood cell production in the bone marrow.
What is the normal range for glomerular filtration rate (GFR)?
Normal GFR is determined by blood flow and blood pressure.
Specific numerical values for normal GFR typically range from 90 to 120 mL/min in healthy adults.
What factors determine GFR?
- Total surface area available for filtration
- Number of nephrons
- Filtration membrane permeability
- Net filtration pressure
- Glomerular blood hydrostatic pressure minus the combined pressure of the osmotic and capsular hydrostatic pressure
The net filtration pressure is critical for determining the rate of filtration.
How does hypertension affect glomerular filtration rate?
Hypertension may impair blood flow to the kidney by:
* Causing hypertrophy of the smooth muscles in the afferent arterioles, reducing the lumen and blood flow
* Damaging the endothelium, accelerating atherosclerosis which reduces blood supply to kidneys
This can lead to decreased GFR and potential kidney damage.
What happens to GFR when blood pressure is low?
Hypotension leads to lower blood flow to the kidneys, potentially resulting in oliguria (<300-500ml/day) or anuria (<50ml/day).
Decreased renal blood flow decreases kidney work and O2 requirements, but extreme reductions can lead to cell death.
What is the glomerular hydrostatic pressure (GBHP) and its significance?
GBHP is the major factor forcing fluids out of the blood and must overcome colloid osmotic pressure and capsular hydrostatic pressure.
A GBHP lower than 55mmHg can occur due to low blood pressure or low cardiac output.
True or False: Kidneys receive 20-25% of the cardiac output.
True
This high percentage is necessary for the kidneys to maintain high rates of glomerular filtration.
Fill in the blank: Severe hypertension can cause damage to the endothelium which accelerates _______.
[atherosclerosis]
Atherosclerosis can lead to reduced blood flow and oxygen delivery to the kidneys.
What occurs if renal blood flow drops below 20% of normal?
Renal cells do not meet O2 requirements at rest and may die.
This situation can lead to severe kidney dysfunction.
What is oliguria?
Oliguria is defined as urine output of less than 300-500ml/day.
It can be an indicator of kidney dysfunction or failure.
What is anuria?
Anuria is defined as urine output of less than 50ml/day.
A critical condition indicating severe kidney failure.
Which of the following hormones is produced in the kidney?
1. ADH
2. Aldosterone
3. Erthropoietin
4. Angiotensin
- Erthropoietin
True or false, The nephron is the basic functional unit of the kidney?
True
The glomerular filtration rate (GFR) is a key lab measurement of the presense and/or degree of kidney injury/disease/failure… T or F?
True!
