Acute Kidney Injury Flashcards
What is another term for acute kidney injury?
Acute kidney failure
What is an acute kidney injury?
It is defined as an acute drop in kidney function over a period of days to weeks
This reduction in kidney function tends to be reversible
Define AKI stage one
Serum Creatinine - >26.5µmol/L (0.3mg/dl) increase or 1-1.9 times baseline within 48 hours OR > 50% increase in 7 days
Urine Output - <0.5mk/kg/hr for 6-12 hours
Is a diagnosis of AKI indicated when serum creatinine levels increase greater than 26µmol/l, however still remain within the ‘normal’ range?
Yes
What is the diagnostic criteria of stage one AKI in children and young adults?
EGFR reduction > 25%
Define AKI stage two
Serum Creatinine - 2.0-2.9 times baseline
Urine Output - <0.5mk/kg/hr for >12 hours
Define AKI stage three
Serum Creatinine - > 354 µmol/L increase or 3 times baseline
Urine Output - <0.3mk/kg/hr for >24 hours or anuria for > 12 hours
How do we define an AKI prolonged over a period greater than three months?
End-stage kidney disease
What are the seven risk factors of AKI?
Older Age > 65 Years Old
Chronic Kidney Disease
Diabetes Mellitus
Heart Failure
Liver Disease
Nephrotoxic Drugs
Emergency Surgery
Which twelve nephrotoxic drugs are associated with acute kidney injury?
ACE inhibitors
ARBs
Potassium Sparing Diuretics
NSAIDs
Metformin
Digoxin
Lithium
Methotrexate
Gentamicin
Co-Trixamazole
Trimethoprim
Iodinated Contrast
In AKI patients, how to we prevent risk of contrast induced kidney injury?
We offer IV hydration before and after contrast infusion
What are the three classifications of acute kidney injury causes?
Pre-renal
Renal
Post-renal
What category of AKI causes is most common?
Pre-renal
How do pre-renal causes lead to an AKI?
There is an inadequate blood supply (hypoperfusion) to the kidney, thus reducing the filtration of blood
What are the five pre-renal causes of an AKI?
Heart Failure
Cardiogenic Shock
Renal Artery Stenosis
Hypovolaemia
Haemorrhage
In most cases what is hypovolaemia related to?
Vomiting
Diarrhoea
What feature of AKIs indicate a pre-renal cause?
A good response to fluid challenge
How do renal causes lead to an AKI?
The intrinsic kidney diseases, which cause damage to the glomeruli, renal tubules or interstitium of the kidneys themselves, thus reducing filtration of blood
What are the seven renal causes of an AKI?
Glomerulonephritis
Acute Tubular Necrosis
Acute Interstitial Nephritis
Rhabdomyolysis
Tumour Lysis Syndrome
Multiple Myeloma
Nephrotoxic Drugs
How do post-renal causes lead to an AKI?
An obstruction of urine flow from the kidney causes back-pressure into the kidney and therefore reduced kidney function
What are the five post-renal causes of an AKI?
Unilateral Renal Calculi
Benign Prostate Hyperplasia
Colon Cancer
Prostate Cancer
Cervical Cancer
What are the eight clinical features associated with AKIs?
Oliguria
Peripheral Oedema
Pulmonary Oedema
Arrythmias
Pericarditis Features
Encephalopathy Features
Hypertension
Increased JVP
What is oliguiria?
It is defined as a decreased urine output < 0.5ml/kg/hr
How are arrhythmias associated with AKIs?
They can develop secondary to potassium changes
How is pericarditis associated with AKIs?
It can develop as a result of uraemia complications
How is encephalopathy associated with AKIs?
It can develop as a result of uraemia complications
What are the five investigations used to diagnose an AKI?
Urine dipstick test
Blood tests
Ultrasound scan
ECG scan
Renal biopsy
What six urine dipstick test results indicate acute kidney injury?
Haematuria
Proteinuria
Positive Leukocytes
Positive Nitrites
Positive Glucose
Positive Urine Bence Jones Protein
What is haematuria on a urine dipstick test?
It is defined as a dipstick positive result of 1+ blood
What is the most important investigation used to diagnose acute kidney injury?
Urine Dipstick
What cause of acute kidney injury is indicated by the presence of haematuria on a urine dipstick test?
Acute nephritis
What is proteinuria on a urine dipstick test?
It is the presence of more than 1.5g of protein in urine per day
What cause of acute kidney injury is indicated by the presence of proteinuria on a urine dipstick test?
Acute nephritis
What cause of acute kidney injury is indicated by the presence of leukocytes on a urine dipstick test?
Infection