CPT2: Renal Flashcards
What are the three classifcations of renal diseases?
- Pre-renal
- Renal
- Post-renal
What is pre-renal disease?
- Reduction in CO or Blood volume
- Problems occuring before the renal e.g. CO problems or ability to perfuse the kidneys
What is renal disease?
- Occurs in the renal structure e.g. Vascular, endothelial, glomerular dysfunction or necrosis
- May be problems with glomerular leaking, scarring, damage to tubing due to abnormal growth/ cells dying
What is post-renal disease?
- Blockage of ureter - kidney stones, infiltrating tumour, prostate
- Can directly or indirectly block. Blockage of tubing leaving the Renal can lead to build up of pressure and damage e.g. unrine infection
What are the 2 classifications based on time periods for kidney diseases?
- Acute kidney injury
- Chronic kidney disease
What is Acute kidney disease?
- Covers a variety of injuries to kidneys from a range of causes
- Often classified by decline in renal excretory function over hours or days
- Rapid change but short time period
- Failure to maintain electolyte, fluid, acid-base homeostasis
What is Chronic kidney disease?
Abnormal kidney function or structure present for more than 3 months, with health implications
What are examples of pre-renal causes and there resepecable causes
- Decreased CO
- Heart failure
- Hypotension
- Myocardial infraction
- operative (operation theatre CO dcr)
- Hypovolemia (loss of volume)
- Sweating
- Haemorrahge - leakage leads to loss of fluid
- Diuretics - dcr fluid volume
- Burns - loss of insulation layer which helps keeps fluid in
- Systemic Dilation
- pharmacological vasodilation - drugs which cause peripheral vasodilartion to CVS effect blood supply tothe kidney
- Sepsis
What is pre-renal damage to the kidney usually caused by? what is this called?
Lack of perfusion (ischaemia) / ocygen to maintain tissues
What are examples of causes of renal failure?
- Afferent/ efferent arterioles
- Tubules
- Glomerulus
What are types of diagnostic imaging and what do these show?
- X-ray and Ultrasound
- Kidney stones
- Cancer
- Kidney size
- Intravenous excretory urogram
- Contrast media to show perfusion
- Structure
- Voiding
- Renal angiogram
- Confirm diagnosis and/ or check renal vascular anatomy
- Biopsies
- Taking renal samples
- Diagnose cause of kidney disease
- GFR/ eGFR
What is the most frequent test for renal function?
GFR
What is clearance?
The volume of plasma cleared of a substance by glomerular filtration through the kidney
What is the equation for clearance? what are each of the parameters?
Cl = (U x V)/ P
CL = clearance
U= Conc of drug/metabolite in urine
V= Rate of urine formation of drug/ metabolite (ml/min)
P= conc of drug/ metabolite in plasma
- How does GFR tend to be measure?
- What is used and why?
- What else can be used?
- What are the disadvantages?
- What are these techniques generally used for?
- Inject inulin
- Inulin isn’t absobed, metabolised, secreted in the renal system
- Radio isotopes and radio-contrast agents
- Time consuming and costly
- Monitoring chemotherapy and evaluation of renal function in living poteital kidney donors
- What is eGFR?
- What substance is used instead and how is it synthesised?
- How is it done
- Disadvantages
- Estinated GFR
- Creatinine - produced by skeletal muscle at rough;y a constant rate so plasma conc depends on rate of excretion by the kidneys
- 2hr urine collection (measures creatinine in urine. Blood samples taken to measure creatinine in plasma. Then equation used.
- Usually Over estimation, time consuming