Acute Kidney Injury Flashcards
What are the three categories of causes for AKI?
Pre renal - anything that limits perfusion to the kidneys
Intrinsic - Pathology in the kidneys
Post renal - Obstruction and a back up causing hydronephrosis low GFR
What are the initial signs of AKI?
High urea (particularly intrinsic, post renal)
High creatinine (particularly intrinsic, post renal)
Hyperkalaemia - less excretion
Metabolic acidosis - less bicarb and K+ taken up by cells in exchange for H+
Oliguria
What are some causes of pre renal AKI?
7 listed
Hypovolaemia - diarrhoea, vomiting
Cardiogenic shock
NSAIDS - Restrict afferent arterioles
ACEI/ARB - Dilates efferent arterioles
Hepatorenal syndrome - Liver cirrhosis causes vasodilation of celiac, mesentary arteries so lowers renal flow
Renal artery Stenosis
Third space sequestration - Hypovolaemia due to bowel obstruction and fluid going to interstial space
(Intrinsic) - What is Acute Tubular Necrosis (ATN)?
Name 4 things that can cause it
This is damage to the tubules as a result of nephrotoxins:
Aminoglycosides (gentamycin)
Radiocontrast
Rhabdomyolysis - Myoglobin
Haemoylysis - Haemoglobin
(Intrinsic) - What is glomerulonephritis. When does it often occur?
Inflammation of the glomeruli
It usually occurs post infection
(Intrinsic) - Why does vasculitis cause intrinsic AKI?
Inflammation of renal vessels
(Intrinsic) What is Acute tubulo interstitial nephritis?
This is an allergic reaction causes inflammation of the interstitium and is usually caused by:
Drugs (NSAIDS, penicillins)
Infection - antigens cause allergic reaction
How do you treat AKI?
Treat underlying cause eg, fluid increase, withdraw drug
Treat complications - see other slides
What are three life threatening complications of AKI?
Metabolic acidosis
Hyperkalaemia
Pulmonary oedema
How do you treat AKI related metabolic acidosis?
Treat underlying cause
Volume expansion if diarrhoea and vomiting
IV sodium bicarb if serious
Dialysis if serious
Why do you get hyperkalaemia with AKI and what can it cause?
K+ not excreted
Muscle weakness
Constipation
Arrythmias and (bradycardia, no P, Peaked T, VT)
How do you treat AKI associated hyperkalaemia?
- Insulin and glucose to activate linked glucose potassium transporter
- Calcium titrated to counteract potassium in the heart
- Salbutamol - shifts potassium intracellularly
What do you get pulmonary oedema with AKI?
Decreased renal flow causes reduced GFR and fluid build up
How do you treat pulmonary oedema with AKI?
Ferusomide
Why do you get metabolic acidosis with AKI?
Less bicarb produced and also hyperkalaemia causes cell absorption of K+ in exhange for H+
No anion gap - CL- replaces bicarb eg diarrhoea, vomiting
Anion gap - replaced by something else, eg DKA renal failure
