What is the normal renal resistive index?

Normal RRI is 0.58–0.64 in adults. RRI >0.70 is associated with intrinsic renal disease, renal vein thrombosis, and is an independent predictor of AKI non-reversibility after cardiac surgery.

Can RRI predict which AKI patients will not recover?

RRI >0.74 in ICU patients with AKI predicts non-recovery with high accuracy in several studies, potentially identifying patients where aggressive renal replacement therapy is unlikely to result in renal recovery.

RRI — Renal Resistive Index by Doppler Ultrasound

Calculate the Renal Resistive Index (RRI = (Peak Systolic Velocity − End-Diastolic Velocity) / Peak Systolic Velocity) from renal Doppler ultrasound to assess renal vascular resistance and predict AKI reversibility.

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RRI — Renal Resistive Index by Doppler Ultrasound

Frequently Asked Questions

What is the normal renal resistive index?

Can RRI predict which AKI patients will not recover?