Acute Kidney Injury Flashcards
What is acute kidney injury?
Acute drop in kidney function in <48hrs
What are the 3 diagnostic criteria?
Rise in serum creatine of >/= 26.4 micromol/l in 48hrs
OR
50+% rise in serum creatine within 7 days
OR
A fall in urine output <0.5ml/kg/hr for 6+ hrs
How are the causes of AKI split up?
Give 3 examples of each
What is the most common category of causes?
- Pre-renal (due to inadequate blood supply)
- Dehydration
- Hypotension
- Heart failure
Renal (due to intrinsic disease)
- Glomerulonephritis
- Interstitial nephritis
- Acute tubular necrosis (ATN)
Post-renal (obstruction to outflow)
- Kidney stones
- Masses in abdo/pelvis
- Ureter/urethral strictures
- Enlarged prostate/prostate cancer
When would an USS be indicated?
To check for obstruction of urinary tract in suspected post-renal AKI
What is the mnemonic to remember the nephrotoxic drugs that should be stopped in AKI?
DAMN
Diuretics
ACE/ARB
Metoformin
NSAIDS
(NB: ACEi are only causative in acute kidney injury - very useful for reducing proteinuria so used in other kidney conditions)
SPIRONOLACTONE AND GENTAMICIN
What is the useful mnemonic for assessment and management?
RENAL DRS 26
Record baseline creatine (+regular U+E's) Exclude obstruction (clinical/USS) Nephrotoxic drugs stopped Assess fluid status Losses +/- catherisation
Dipstick (blood/protein)
Review meds
Screen (consider acute renal screen)
26 creatine rise for AKI diagnosis
Why should an ECG be taken in a patient with AKI?
To check for hyperkalaemia
Peaked T wave
What can result from a build up of urea due to poor GFR?
Uraemic complications e.g. encephalopathy + pericarditis
What ABG is most likely in AKI?
Metabolic acidosis
due to lack of ammonia secretion - ammonia is an acid
What is the most common cause of AKI?
Acute tubular necrosis
Destruction and damage of the tubular epithelial cells
Muddy brown casts on urinalysis?
Acute tubular necrosis
What type of AKI accounts for 1/4 of drug induced AKI?
Acute interstitial nephritis
Rise in urea and creatine levels post new drug. Patient presents with fever and rash as well.
What is their urinalysis likely to show?
What condition is this?
Acute interstitial nephritis
Allergic picture
- increased WCC
- increased IgE
- increased eosinophils
What kind of AKI can be caused by sepsis?
Acute tubular necrosis