AKI Flashcards
define an AKI
an abrupt loss of kidney function resulting in the retention of urea and other nitrogenous waste products and the dysregulation of extracellular volume and electrolytes.
what are the criteria for an AKI?
o Increase in serum creatinine > 26 mol/L within 48 hrs
o Increase in serum creatinine to > 1.5 times baseline within the preceding 7 days
o Urine volume < 0.5 ml/kg/hr for 6 hours
what are the catagories of causes of an AKI?
- Pre-Renal
- Intrinsic Renal
- Post-Renal
what are pre-renal causes of an AKI?
o Caused by inadequate renal perfusion
- Dehydration
- Vomiting
- Haemorrhage
- Heart failure
- Sepsis
what are intrinsic causes of an AKI?
o Glomerular
o Tubular - acute tubular necrosis (MOST COMMON)
o Interstitial
o Vasculitides
what are post renal causes of an AKI?
obstruction o Calculi o Urethral stricture o Benign prostatic hyperplasia o Bladder tumour
sodium and urine osmolality in pre renal causes?
. Urine osmolality is high and urine sodium is low.
sodium and urine osmolality in intrinsic causes?
urine osmolality is low and urine sodium is high
what are the risk factors of an AKI?
o Age o Chronic kidney disease o Comorbidities o History of acute kidney injury o Use of nephrotoxic medications o Sepsis o Hypovolaemia
what are the main affects of an AKI?
o Reduced urine output
o Fluid overload
o Rise in toxic molecules
what is the epidemiology of an AKI?
• Most common in the ELDERLY
what are the presenting symptoms of an AKI?
- Oliguria/anuria
- Nausea/vomiting
- Dehydration
- Confusion
what are the signs of an AKI?
- Hypertension
- Distended bladder
- Dehydration
- Fluid overload
first and second line investigations into an AKI?
First line: bloods and urinalysis
Second line: Renal USS
what might the urea and creatinine tell us?
- when the urea is very high it is dehydration
- when creatinine is really high its a renal cause
