(SYNOPTIC) AKI & CKD Flashcards
What term has ‘acute kidney injury’ replaced?
Acute renal failure
How is AKI loosely defined?
An abrupt/ acute decline in kidney function
- e.g. glomerular filtration
Hours or days
What is the official definition of AKI?
How much serum creatinine has increased from its baseline level over a set period of time
OR
How much urine volume has decreased over a set period of time
How is stage 1 of AKI defined?
(1) 1.5-1.9 times baseline SERUM CREATININE
(2) <0.5ml/kg/h of urine for 6-12 hours URINE OUTPUT
How is stage 2 of AKI defined?
(1) 2.0-2.9 times baseline SERUM CREATININE
(2) <0.5ml/kg/h of urine for ≥12 hours URINE OUTPUT
How is stage 3 of AKI diagnosed?
(1) 3 times baseline SERUM CREATININE
(2) Initiation of renal replacement therapy
(3) Anuria ≤12 hours
How many stages of AKI are there?
3 stages
How many classifications of AKI are there?
3
What are the classifications of AKI?
(1) Pre-renal
(2) Post-renal
(3) Intrinsic
What is pre-renal AKI?
Reduced blood flow to the kidney
What causes pre-renal AKI?
- Reduced BP
- Hypovalaemia (decreased blood volume)
- Dehydration
- GI bleed
- Sepsis
- Cardiac & liver failure
- Burns
- Medications
What is post-renal AKI?
Obstruction to outflow from the kidneys
What causes post-renal AKI?
- Benign prostatic hypertrophy (BPH)
- Prostate cancer
- Renal calculi
- Retroperitoneal fibrosis
- Medications
What is intrinsic AKI?
Damage to the functional tissues of the kidney
What causes intrinsic AKI?
- Acute interstitial nephritis
- Myeloma
- Rhabdomyolysis
- Immunological renal disease
- e.g. vasculitis/ medications
What is the most common classification of AKI?
Pre-renal
Why is it important to check blood creatinine levels?
- If rising, could indicate kidneys are not functioning correctly
- Determine sufficiency of kidney function
- Determine severity of kidney damage
- Monitor progression of kidney disease
How can GFR be calculated?
(1) eGFR (mL/min/1.73m^2)
2) Creatinine clearance (mL/min
What are disadvantages of using eGFR to estimate GFR?
- Does not account for a patient’s bodyweight
- Can dramatically underestimate the creatinine clearance in renal failure
- Not interchangeable between labs
How is creatinine clearance measured?
Cockcroft + Gault equation
What is the Cockcroft & Gault equation?
CrCl = [F(140-age) x weight] / serum creatinine
F = 1.04 in females and 1.23 in males
What is F in females?
1.04
What is F in males?
1.23
What is eGFR?
Estimated glomerular filtration rate
Calculated in labs