Acute Kidney Injury Flashcards
What is acute kidney injury?
Acute kidney injruy is a syndrome with a adrupt decline in actual GFR, for example due to ann upset in ECF volume, electryltye and acid base homestasis
What are the three causes of acute kidney failure?
Pre renal failure
Intrinsic renal failure
Post renal failure
What are some of the causes of intrinisic renal failure?
Intrarenal vascular, glomeulornephritis, ischameic ATN, Toxic ATN and intestital disease
What is the causes (pathophysiology) of a pre renal AKI?
Acutal GFR is reduced due to a reduced renal blood flow, no cell damage so the kidneys work hard to restore renal blood flow, avid reasoprtion of salt and water, and responds to fluid resitutitation
What happens to kidney autoregualtion in hypertensive patients?
The range at which the kidney retains normal function is at a higher blood pressure and therefore a drop to a normal level of blood pressure could result in a acute kidney injury
How can drugs acting on the autoregulartoy system
NSAIDS stop prostaglasings which are vasodilitors that keep normal afferent tone, where as ACE inhibitors stop vasoconstriction of the efferent aterioles
What are the two main proccesses that can cause pre renal failure?
Reduced effective extracellular fluid volume ( hypovolemia, cardiac dysfunction or systemic vasodilation), there is also impaired renal autoregulation, due to in preglomular vasoconstiction, and post glomular vasodilation
What can happen as a result of poor renal perfusion?
Acute tubular necrosis
What are the potential causes of acute tubular necrosis?
Can be caused by ischeamia, nephrotocxins and sepsis
Where is the most common area of tubular injury within ishemia?
The S3 segment of the neprhon and the most hypoxic area of the tubule is between the cortex and the medulla
What are nephrotoxins?
Damage the epitheal cells lining the tubules, and cause cell death and then shedding into the lumen
What are some of the endogenous nephortoxins?
Myoglobin, urate,m bilirubin which is an extra insult to the kidneys in people who have liver damage
What are some exogenous nephrotoxins?
Endotxin, X ray contrast,, drugs suhc as ace inhibitors, aminoglycosides, NSAIDS
What are some of the glomeular and ateriolar diseases that can result in acute kidney injury?
Acute glomeular nephritis, which is a immune disorder affecting the glomeulri, primary where the disease only affects the kindeys, and secondary where the disease is involved as part of a ssystemic proccess
What are some of the histological features of glomeularnephritis/
Granulmatosis wiht polynpephritis, and crescenitng necrostising glomeulronephitirs,
