Impact of acute kidney injury (AKI) according to KDIGO staging criteria on 28-day mortality in critically ill patients: a prospective observational study

Acute kidney injury is one of the most common organ impairments seen in intensive care units. An estimated 7.5% of hospitalized population in South Asia develops AKI. The incidence is much higher in ICU patients, varying from 1 in 3 to 2 in 3, based on the diagnostic criteria used. Acute kidney injury is a concern for physicians given its association with increased length of ICU stay, health care costs and in-hospital mortality in short term to increased risks of cardiovascular events, progression to chronic kidney disease, and long-term mortality. A strong and graded relationship between AKI severity and increased mortality has been established.

Given the significance of AKI on patient outcome, Risk, Injury, Failure, Loss, End-Stage (RIFLE) criteria by Acute Dialysis Quality Initiative (ADQI) and later, updated Acute Kidney Injury Network (AKIN) criteria aimed to define and stage AKI. In 2012, Kidney Disease Improving Global Outcomes (KDIGO) staging system was introduced which combined the previous 2 systems and is currently the recommended system. These systems rely on three diagnostic criteria: a rise in serum creatinine (SCr), a decrease in urine output (UO), and administration of renal replacement therapy (RRT), to define AKI into various stages.

However, it has been observed in various studies that KDIGO criteria do not encompass all the factors that adversely affect patients with AKI. Additionally, categorization of severity of AKI using KDIGO criteria may not always be accurate.

We plan to perform a prospective observational study on impact of AKI severity & other patient and disease related factors on mortality, in critically ill patients.