Acute kidney injury

Definition

Acute kidney injury (AKI) describes a rapid deterioration in a patient’s renal function over a few hours/days. One in five emergency admissions to hospital will have AKI and around 30% of AKI cases could be preventable.

Classification

AKI can be classified in three stages of severity: 

Stage	Serum creatinine	Urine output*
1	Increase by ≥ 26 micromol/L within 48 hours OR 1.5-1.9 times baseline	<0.5 ml/kg/h for 6-12 hours
2	2.9 times baseline <0.5 ml/kg/h for ≥12 hours	<0.5 ml/kg/h for ≥12 hours
3	3 times baseline OR Increase to ≥354 micromol/L OR Decrease in eGFR to <35 ml /min OR Initiation of renal replacement therapy	<0.3 ml/kg/h for ≥24 hours

 

Responding to AKI

If you suspect AKI alert a senior colleague. You may be requested to perform urine dipstick and send for MSU, take further blood tests and report these to a senior colleague. The team may consider urinary catheterisation and review all medications.

Learn more by completing the NICE AKI module at: nice.org.uk

*Accurate monitoring and recording of fluid balance including urine output is essential. thinkkidneys.nhs.uk