Utility of renal resistive index as an early marker of acute kidney injury related to intra-abdominal pressure in critical ill patients.

There is a direct relationship between intra-abdominal hypertension (IAH) and acute kidney injury (AKI). The current AKI scales are not always an early marker of renal damage. The use of renal resistive index (RI) measured by eco-Doppler method for early detection of AKI in critically ill patients is postulated. The RI is a parameter obtained from the study of the flow of the arcuate or renal interlobar arteries. The formula is: RI = (systolic peak velocity -diastolic end velocity) / systolic peak velocity. The definite result is an average of 3-5 pulse waves.