Pediatric Renal Angina Index

The renal angina index is a predictive tool, performed on admission to the pediatric intensive care unit, and used to assess the risk for subsequent severe AKI (≥ doubling of serum creatinine) 72 h later (Day-3 AKI).

The angina index is a composite of risk strata and clinical signs of injury.

Risk strata were given point values that were essentially the epidemiologic risk compared to general pediatric risk divided by 10:

• ICU admission alone: Moderate risk with a score of 1
• Stem cell transplantation: High risk with a score of 3
• Ventilation or intropes: Very high risk with a score of 5

Clinical signs of injury are based on changes in estimated creatinine clearance (eCrCl) or % fluid overload (%FO).

The point values for injury are:

• 1 - No decrease in eCrCl or <5% FO
• 2 - >5% FO or eCrCl decrease of 0-25%
• 4 - >10% FO or eCrCl decrease of 25-50%
• 8 - >15% FO or eCrCl decrease of >50%

The possible RAI scores therefore range from 1 to 40. A cutoff of ≥8 is used to determine renal angina fulfillment.

Notes:
The electronic health record was reviewed for the lowest SCr up to 3 months before PICU admission to establish a reference eCcCl. If no SCr was available, a reference eCCl of 120 ml/min per 1.73 m2 was used.

Fluid overload was defined as a percentage equal to (fluid in [L] - fluid out [L])/(ICU admit weight [kg]) x 100%.

When determining the score for 'injury' score, the worse parameter between change in eCrCl from baseline and % fluid overload was used.