Renal resistive index as predictor of acute kidney injury after major surgery: A systematic review and meta-analysis

• Published in: Journal of critical care Vol. 50; pp. 36 - 43
• Main Authors: Bellos, Ioannis, Pergialiotis, Vasilios, Kontzoglou, Konstantinos
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.04.2019; Elsevier Limited
• Subjects: Acute kidney injury; Acute Kidney Injury - diagnosis; Biomarkers; Confidence intervals; Diabetes; Evidence-based medicine; Humans; Intensive care; Kidney - blood supply; Kidney - diagnostic imaging; Kidneys; Meta-analysis; Nomograms; Postoperative; Postoperative Complications - diagnosis; Postoperative period; Predictive Value of Tests; Renal replacement therapy; Renal resistive index; Statistical analysis; Surgery; Systematic review; Ultrasonography, Doppler; Vascular Resistance - physiology; Postoperative; Renal resistive index; Acute kidney injury; Surgery; Meta-analysis
• ISSN: 0883-9441; 1557-8615; 1557-8615
• DOI: 10.1016/j.jcrc.2018.11.001

To determine the efficacy of Doppler renal resistive index in the prediction of acute kidney injury after major surgery. A systematic review and meta-analysis of cohort studies was conducted. Medline (1966–2018), Scopus (2004–2018), Clinicaltrials.gov (2008–2018) and Google Scholar (2004–2018) databases were systematically searched. Prospective studies that examined the diagnostic accuracy of renal resistive index in postoperative acute kidney injury were included. The meta-analysis was based on 10 studies, including a total number of 911 patients. Patients who developed acute kidney injury presented higher renal resistive index values preoperatively (MD: 0.02, 95% CI: [0.00–0.03]), immediately after surgery (MD: 0.07, 95% CI: [0.04–0.11]) and 24 hours postoperatively (MD: 0.07, 95% CI: [0.04–0.09]). The pooled sensitivity was 81.8%, the specificity 77.6% and the area under the curve 0.866. Fagan's nomogram indicated that the post-test probability was increased to 60.6% (positive test) and decreased to 9.5% (negative test), when the pre-test probability was 30%. Renal resistive index represents a useful marker with fair performance in the prediction of postoperative acute kidney injury. Future cohorts should establish the optimal timing of measurement and evaluate the most appropriate cut-off value that should be used in the clinical setting. •Prediction of postoperative acute kidney injury is essential.•Renal resistive index increases in patients with acute kidney injury after surgery.•The predictive efficacy of renal resistive index is promising.•Future studies should define the optimal cut-off values.