AKI Flashcards
What is AKI?
Decreased renal function over hours-days, 2ndary to other disease.
NICE criteria for AKI?
Rise in creatinine: >26 micromol/L (48h) OR
Rise in creatinine: >50% (7 days) OR
Urine output: <0.5ml/kg/hr (>6 hrs)
Staging of AKI?
Stage 1: minimum NICE criteria
Stage 2: >100% rise in creatinine (7 days) OR <0.5ml/kg/hr (12 hrs)
Stage 3: >353 micromol/L (48h) OR <0.3ml/kg/hr (24hrs)
What is Pre-renal AKI?
AKI caused by reduced perfusion to kidneys/hypoxia
85% cases
Common Causes of pre-renal AKI?
SCAR
1) Systemic vasodilation - sepsis, hypotension
2) Cardiac output - MI, severe heart failure
3) Acute Volume loss: Haemorrhage, diarrhoea, vomiting
4) Renal vasoconstriction - Hepatorenal syndrome, nephrotoxic drugs
Nephrotoxic Drugs examples?
DAMN: Diuretics, ACE/ARBs, Metformin, NSAIDs
What is Renal AKI?
AKI caused by intrinsic kidney disease.
Common Causes of Renal AKI?
Inflammation
1) 1ary Glomerulonephritis, Acute Tubular Necrosis (hypoperfusion), rhabdomyolysis
2) Interstitial nephritis: Infection, infiltration
3) Vasculitis - 2ndary GN
What is post-renal AKI?
AKI due to obstructive disease, result = back pressure.
Common Causes of Post-Renal AKI?
1) Renal tract block: Stones, strictures, ureter malignancy.
2) Extrinsic block: Pelvic malignancy, Prostate enlargement.
Relevant Investigations for AKI?
1) Hydration Status Examination
2) Obs/Record fluid balance chart (via catheter)
3) eGFR test
4) Urine dip + U&Es (sodium, potassium + creatinine)
5) Renal Ultrasound
6) Immunoglobulin + Bence Jones proteins (myeloma) screen
Management for AKI
1) Treat underlying conditions: stop nephrotoxic drugs (metformin if eGFR <30), relieve obstruction, treat infection.
2) Rehydration therapy
3) Escalate/referral to specialist renal team.
