AKI Flashcards
What is the definition of AKI?
Increase in Serum Creatinine
by ≥ 26.5 μmol/l (0.3 mg/dl ) within 48 hours; or
to ≥ 1.5 times baseline, which is known or presumed to have occurred within the prior 7 days; or
Urine volume <0.5 ml/kg/h for 6 hours
Describe AKI stage I?
1.5-1.9 x creatinine baseline
or >26.5 umol/l increase
Or <0.5ml/kg/h urine output for 6-12 hours
Describe AKI stage 2 ?
2.0-2.9 x baseline creatinine
or <0.5ml.. urine output for >12 hours
Describe AKI stage 3
3.0x baseline creatinine Or increase to >354 umol Or initiation of RRT Or <0.3 ml.. urine for >24 hours Or anuria for >12 hours
What are the immediate dangerous causes of AKI?
Acidosis
Electrolyte imbalance
Intoxication
Overload
What are the 3 categories of causes of AKI?
Pre renal
Renal
Post Renal
What is the commonest cause of pre-renal AKI?
Reduction in effective circulation volume
What are some potential causes of pre-renal AKI?
Reduce effective circulation volume
- Volume depletion (haemmorhage / dehydration)
- Hypotension / shock (sepsis is major contributor)
- Congestive cardiac failure / Liver failure
Arterial occlusion
Vasomotor
- NSAIDs/ACE inhibitors
What are some renal causes of AKI?
Acute tubular necrosis Toxin related Acute interstitial nephritis Acute glomerulonephritis Myeloma Intra renal vascular obstruction
What are some post renal causes of AKI?
Obstruction
What can cause intraluminal obstruction
Calculus
clot
What can cause intramural obstruction?
Malignancy
Ureteric stricture
Radiation fibrosis
Prostate disease
What can cause extra mural disease?
Retroperitoneal fibrosis
Malignancy
What is radiocontrast nephropathy?
AKI following administration of iodinated contrast agent
What is the prognosis for radiocontrast nephropathy?
Usually transient renal dysfunction Resolving after 72hrs
May lead to permanent loss of function
What are the risk factors for radiocontrast nephropathy?
DM Renovascular disease Impaired renal function Paraprotein High volume of radiocontrast
What direct history questions are relevant for AKI?
FH
Drug exposure
PMH
What examinations/signs are relevant for AKI?
Flid status
Vital signs (BP, pulse)
Systemic illness
What investigations should be done for AKI?
Urine dipstick Bloods FBC Blood gas USS
Which blood tests should be requested for AKI?
U&E Bicarbonate Clotting FBC ANCA IG immunoglobulins C3 complement
Which urine tests should be carried out?
Blood
Protein
What histological investigations should be carried out for AKI?
Renal biopsy
What are risk events for AKI?
Sepsis Toxins Hypotension Hypovolaemia Major surgery
What things can cause hypovolaemia?
Haemorrhage
Vomiting
Diarrhoea
What are risk factors for AKI?
>75 Previous AKI HF Liver disease Chronic kidney disease Vascular disease
Which toxins can cause AKI?
X-ray contrast
NSAID’s
Gentamicin
Which antibiotic is contraindicated in renal problems?
Gentamicin
Which measures can be taken to supportively manage fluid balance in AKI?
Volume resuscitation if vol depleted Fluid restriction if vol. overload Optimise BP Give fluid/vasopressers Stop ACE inhibitors
What is the management for toxin related AKI?
Stop nephrotoxic drug
Do not give IV radiocontrast unless needed
Use antidote if available
What step should be taken if patient hypotensive in AKI?
Stop anti-hypertensives drugs
What ECG changes are seen in hyperkalaemia?
Peaked T waves
P wave widened and flatened
PR segment lengthened
What can hyperkalaemia cause?
VF/asystole
Cardiac arrests
Death
When do you give dialysis in AKI?
Low carbonate
High potassium
Pulmonary oedema
Pericarditis
Where is haemodialysis given?
kidney unite
