AKI Flashcards
What is AKI?
A rapid drop in kidney function diagnosed by measuring serum creatinine
What are the criteria for diagnosis of an AKI?
A rise in creatinine of 26 micromol/L or greater within 48 hours
A 50% or greater rise in serum creatinine in 7 days
A fall in urine output to less than 0.5ml/kg/hour for more than 6 hours
What are the risk factors for AKI?
Older age
Sepsis
CKD
Heart failure
Diabetes
Liver disease
Cognitive impairment - reduced fluid intake
Medications
Radiocontrast agents
What medications commonly cause AKI?
NSAIDs
Gentamicin
Diuretics
ACE inhibitors
ARBs
What are the pre-renal causes of AKI?
Dehydration
Shock
- Haemorrhagic shock
- Cardiogenic shock
- Septic shock
- Anaphlactic shock
Heart failure
Drugs
What are the renal causes of AKI?
Acute tubular necrosis
Glomerulonephritis
Acute interstitial nephritis
Haemolytic uraemic syndrome
Rhabdomyolysis
What are the post-renal causes of AKI?
Kidney stones
Tumours
Ureteral or urethral stricture
BPH
Neurogenic bladder
What is the most common intrinsic cause of AKI?
Acute tubular necrosis
What is acute tubular necrosis?
The damage and death of epithelial cells of the renal tubules (due to hypoperfusion or nephrotoxins)
What investigations are performed in suspected AKI?
Serum creatinine
Urinalysis
Ultrasound of urinary tract (to determine post-renal cause)
ABG
Bloods - FBC, U&E, LFTs, glucose, CK, CRP
ECG - hyperkalaemia
CXR - pulmonary oedema
What is a stage 1 AKI?
Rise of >26micromol or more within 48 hours
Rise in creatinine of more than 50% in 7 days
Urine output less than 0.5ml/kg/hour for more than 6 hours
What is a stage 2 AKI?
More than 100% rise in creatinine in 7 days
Urine output less than 0.5ml/kg/hour for more than 12 hours
What is a stage 3 AKI?
More than 200% rise in creatinine in 7 days
Urine output less than 0.3ml/kg/hour for 24 hours
Anuria for 12 hours
What is the management of AKI?
IV fluids
Withhold medications that may worsen the condition
Withhold/adjust medications that may accumulate with reduced renal function
Relieve obstruction in post-renal AKI
Dialysis
What are the complications of AKI?
Fluid overload
Heart failure
Pulmonary oedema
Hyperkalaemia
Metabolic acidosis
Uraemia