The definition of AKI is an abrupt and sustained decline in glomerular filtration rate (GFR). If creatinine is rising, GFR may be close to zero and therefore eGFR is of no value in the assessment of AKI. AKI is classed into three stages (table 1). Common risk factors for AKI are listed in table 2. This list is not exhaustive.
Table 1 – Stages of AKI
I Rise in creatinine of ≥1.5-1.9 from baseline
II Rise in creatinine of ≥2.0-2.9 from baseline
III Rise in creatinine of ≥3 from baseline
Table 2 – AKI risk factors
Patients at risk of developing AKI
• Chronic kidney disease (CKD)
• Chronic liver disease (CLD)
• Congestive cardiac failure (CCF)
• Those on polypharmacy
Other risk factors for AKI
Drugs including ACEi/ARB/NSAIDs and contrast*
*If contrast is necessary and a patient has an AKI or CKD with an eGFR ≤30ml/min, the radiologist should be informed and consider administering 1 litre of saline in the 12 hours prior to and following the scan. Urgent and essential scans should not be delayed to allow fluid administration.