Acute kidney injury Flashcards
(9 cards)
What is Acute Kidney Injury (AKI)?
AKI is a sudden decline in renal function, characterized by a reduction in renal excretory function over hours or days, leading to an inability to maintain fluid, electrolyte, and acid-base balance.
What are the three types of causes of AKI?
Pre-renal: Due to reduced perfusion of the kidneys (e.g., hypotension).
Intra-renal: Due to structural damage to the kidneys.
Post-renal: Due to acute urinary tract obstruction.
Which people are at increased risk for AKI?
People aged 65 years or over.
People with a history of AKI, CKD, heart failure, liver disease, or diabetes.
People with reliance on others for fluid intake.
People with sepsis, hypovolemia, or dehydration.
People using specific medications.
What are some complications associated with AKI?
Hyperkalaemia, metabolic acidosis, fluid overload, uraemia, and CKD.
How is AKI diagnosed?
A rise in serum creatinine of 26 micromol/L or more within 48 hours.
A 50% increase in serum creatinine in the past 7 days.
A fall in urine output to less than 0.5 mL/kg/hour for more than 6 hours.
Which drugs should be avoided in AKI due to pre-renal AKI risk?
NSAIDs: Cause vasoconstriction, reducing blood flow to kidneys.
ACE inhibitors/ARBs: Reduce glomerular filtration pressure.
Diuretics: Can cause dehydration, leading to reduced renal perfusion.
Which medications can cause intrinsic AKI?
Aminoglycosides: Nephrotoxic to renal tubules.
Contrast agents: Can cause contrast-induced nephropathy.
Methotrexate: Crystallizes in renal tubules, causing damage.
Penicillins and Cephalosporins: Can cause acute interstitial nephritis.
Proton Pump Inhibitors (PPIs): Increase risk of acute interstitial nephritis.
What is the effect of Lithium on the kidneys?
Lithium can cause nephrogenic diabetes insipidus, leading to dehydration and pre-renal AKI, and chronic interstitial nephritis over time.
Why is metformin generally contraindicated in acute kidney injury (AKI)?
Metformin is contraindicated in AKI due to the risk of lactic acidosis, as it can accumulate in the body when kidney function is impaired, especially in cases of dehydration or renal insufficiency. It doesn’t directly cause AKI but can exacerbate kidney injury in these situations.
