Acute kidney injury Flashcards
what is chronic kidney disease
evidence of structural or functional kidney abnormalities that persists for over 3 months with or without decreased GFR under 60.
most common sign is persistent albuminuria
what is AKI
abrupt, usually within hours, decrease in kidney function which has both structural damage and loss of function. mixed aetiology with presence of sepsis, ischaemia and nephrotoxicity often co exist.
difference between nephrotic and nephritic syndrome
Nephritic syndrome is a condition involving haematuria, mild to moderate proteinuria (typically less than 3.5g/L/day), hypertension, oliguria and red cell casts in the urine.
Nephrotic syndrome is a condition involving the loss of significant volumes of protein via the kidneys (proteinuria) which results in hypoalbuminaemia. The definition of nephrotic syndrome includes both massive proteinuria (≥3.5 g/day) and hypoalbuminaemia (serum albumin ≤30 g/L). 1
KDIGO definition of AKI
anyone of these 3
Increase in serum creatinine by more than 0.3 within 48hr
Increase in sCr to 1.5 times baseline occurred in last 7 dyas
Urine volume under 0.5ml/kg/h for 6 hours
kidney disease can be detected in the blood by what two things
urea - produced in liver from protein breakdown filtered by kidney
creatinine - produced at constant rate from muscle proportional to muscle mass - freely filtered
what is creatinine made of what two aa
glycine and adenine
plasma creatinine =
production rate/by clearance rate
what is cystatin c
it is a molecule produced by all proliferative cell where is concentration always remains constant
stages of AKI
stage 1
SCr ≥ 26.5 µmol/L
or
SCr ≥ 1.5-1.9 times baseline
urien output
< 0.5 mL/kg/hr for > 6 hr
2
SCr > >2-2.9 times baseline
urien < 0.5 mL/kg/hr for >12 hr
3
SCr > >3 fold from baseline
or
increase in SCr ≥ 26.5 μmol/L to ≥ 354 μmol/L
or
initiated on RRT (irrespective of stage at time of initiation)
urine
< 0.3 mL/kg/hr for 24 hr
or
anuria for 12 hr
AKI affect most electrolytes
what happens to the ph
calium and phosphate
Acute kidney injury (AKI) is associated with electrolyte and acid-base disturbances such as hyperkalemia, metabolic acidosis, hypocalcemia and hyperphosphatemia
causes of pre renal AKI
hypovolaemia - trauma and burns and blood loss
decreased CO due to cariogenic shock or PE
decreased effective plasma volume to move things out due to neprhtoci, liver failure or spies
renovascualr occasion - thombosis
impaired renal autoregualtion deu to NSAID or ACEI
causes of renal AKI
small vessel disease like DIC
acute GN
nephritis due to drugs infection or sarcoid
drugs such as gentamicin causing nephotociccity
or endogenous with rnhabdomylosis
post renal causes of AKI
bladder outflow obstruction like prostate ca or urehtral obstruction
ureteral obstruction via stones, crystals, tumours and blood clots
risk factors fro AKI
age co-morbiidity medication previous CKD hypovolaemia sepssis urinalysis weight nutrition
You are the FY1 doctor working in the acute medical unit where you see Ethel Smith a 79 year old lady who presents with a fever, dysuria and rigors. She has been eating and drinking less than usual because of abdominal pain and nausea for a week. She cannot remember when she last opened her bowels. You suspect a diagnosis of urosepsis and start antibiotics. Few hours later blood results return from lab and show following
To calculate BCR for patient must convert the rest Blood urea nitrogen- to clacualte urea mmol/lto BUN mg dll divide by 0.357 to convert creatinine micromole to creatien mg dl divide by 88.4
looks like urnary sepsis
