Renal Resistive Index Measurement by Transesophageal Echocardiography: Comparison With Translumbar Ultrasonography and Relation to Acute Kidney Injury.
OBJECTIVES
The aim of this study was to evaluate the relationship between transesophageal ultrasonography-derived renal resistive index values (RRITEE) and a standard translumbar renal ultrasound-derived RRI (RRITLUSG). The effectiveness of each method to predict acute kidney injury (AKI) after cardiac surgery also was compared.


DESIGN
A prospective observational study.


SETTING
A teaching university hospital.


PARTICIPANTS
Sixty patients undergoing cardiac surgery.


INTERVENTIONS
First, RRI was measured with both methods after anesthesia induction. Second, another measurement was performed with TEE after cardiopulmonary bypass and immediately following the surgery with translumbar ultrasound. To test the correlation between the 2 methods and to plot a Bland-Altman graph, preoperative RRI values measured by both techniques were used. Receiver operating characteristic curves also were plotted to compare the diagnostic values of RRI measured intraoperatively by TEE after cardiopulmonary bypass and by RRITLUSG after surgery.


MEASUREMENTS AND MAIN RESULTS
There was a statistically significant correlation between the 2 RRI measurement approaches (r = 0.86, p<0.0001). The Bland-Altman plot indicated good agreement between the methods. The area under the curve (AUC) of RRITEE in predicting AKI was 0.82 (95% confidence interval [CI] = 0.64-0.9, p = 0.001), and the AUC of RRITLUSG after surgery was 0.85 (95% CI = 0.7-0.98, p<0.0001). In predicting AKI, an uncertainty zone for RRITEE values between 0.68 and 0.71 was computed by the gray-zone approach.


CONCLUSIONS
RRITEE showed clinically acceptable agreement with RRITLUSG. Indeed, RRI measured intraoperatively with TEE was comparable to RRITLUSG in terms of detecting postoperative AKI.
['Kararmaz|Alper|A|', 'Kemal Arslantas|Mustafa|M|', 'Cinel|Ismail|I|']
D058186:Acute Kidney Injury D000328:Adult D000368:Aged D006348:Cardiac Surgical Procedures D017548:Echocardiography, Transesophageal D005260:Female D006801:Humans D007668:Kidney D008161:Lumbosacral Region D008297:Male D008875:Middle Aged D016343:Monitoring, Intraoperative D011183:Postoperative Complications D011446:Prospective Studies
renal resistive index transesophageal echocardiography acute kidney injury cardiac surgery Doppler