Predictive performance of renal resistive index, semiquantitative power Doppler ultrasound score and renal venous Doppler waveform pattern for acute kidney injury in critically ill patients and prediction model establishment: a prospective observational study.

BACKGROUND: This study aimed to explore the performance of renal resistive index (RRI), semiquantitative power Doppler ultrasound (PDU) score and renal venous Doppler waveform (RVDW) pattern in predicting acute kidney injury (AKI) in critically ill patients and establish prediction models. METHODS: This prospective observational study included 234 critically ill patients. Renal ultrasound was measured within 24 h after intensive care unit admission. The main outcome was the highest AKI stage within 5 days after admission according to the Kidney Disease Improving Global Outcomes criteria. RESULTS: Patients in the AKI stage 3 group had significantly higher RRI, RVDW pattern and lower PDU score (p < 0.05). Only lactate, urine volume, serum creatinine (SCr) on admission, PDU score and RVDW pattern were statistically significant predictors (p < 0.05). Model 1 based on these five variables (area under the curve [AUC] = 0.938, 95% confidence interval [CI] 0.899-0.965, p < 0.05) showed the best performance in predicting AKI stage 3, and difference in AUC between it and the clinical model including lactate, urine volume and SCr (AUC = 0.901, 95% CI 0.855-0.936, p < 0.05) was statistically significant (z statistic = 2.224, p = 0.0261). The optimal cut-off point for a nomogram based on Model 1 was ≤127.67 (sensitivity: 95.8%, specificity: 82.3%, Youden's index: 0.781). CONCLUSIONS: The nomogram model including SCr, urine volume, lactate, PDU score and RVDW pattern upon admission exhibited a significantly stronger capability for AKI stage 3 than each single indicator and clinical model including SCr, urine volume and lactate.

Semiquantitative Power Doppler Ultrasound Score to Predict Acute Kidney Injury in Patients With Sepsis or Cardiac Failure: A Prospective Observational Study.

BACKGROUND: Diagnosing acute kidney injury (AKI) stage 3 in critically ill patients may help physicians in making treatment decisions. This diagnosis relies chiefly on urinary output and serum creatinine, which may be of limited value. This study aimed to explore the diagnostic performance of renal resistive index (RRI) and semiquantitative power Doppler ultrasound (PDU) scores in predicting AKI stage 3 in patients with sepsis or cardiac failure. METHODS: This study is a prospective observational study that included 83 patients (40 with sepsis and 43 with cardiac failure). Renal resistive index and semiquantitative PDU scores were measured within 6 hours following admission to the intensive care unit. Acute kidney injury was defined according to the criteria set by Kidney Disease Improving Global Outcomes. RESULTS: The predictive values of RRI (area under the curve [AUC] = 0.772, 95% confidence interval [CI] = 0.658-0.886) and PDU score (AUC = 0.780, 95% CI = 0.667-0.892) were similar in all patients. Power Doppler ultrasound score (AUC = 0.910, 95% CI = 0.815-1.000) could effectively predict AKI stage 3 in the cardiac failure subgroup, and the optimal cutoff for this parameter was ≤ 1 (sensitivity = 87.5%, specificity = 92.6%, Youden index = 0.801, accuracy in our population = 90.7%). However, PDU scores (AUC = 0.620, 95% CI = 0.425-0.814) could not predict AKI stage 3 in the sepsis subgroup. The predictive values of RRI for AKI stage 3 in the cardiac failure (AUC = 0.820, 95% CI = 0.666-0.974) and sepsis (AUC = 0.724, 95% CI = 0.538-0.910) subgroups were similar. CONCLUSIONS: Power Doppler ultrasound scores could effectively predict AKI stage 3 in patients with cardiac failure but not in patients with sepsis. Renal resistive index is a poor predictor of AKI stage 3 in patients with sepsis or cardiac failure.

Renal echography for predicting acute kidney injury in critically ill patients: a prospective observational study.

Objective: To investigate the diagnostic performances of renal resistive index (RRI) and semiquantitative power Doppler ultrasound (PDU) scores in predicting acute kidney injury (AKI) stage 3 in critically ill patients.Methods: This prospective observational study included 148 patients (80 with reduced cardiac index [CI], 68 with maintained CI). RRI and semiquantitative PDU scores were measured within 6 h after intensive care unit admission. AKI was defined according to Kidney Disease Improving Global Outcomes criteria.Results: A negative correlation between RRI and PDU score (r = -0.517, p < 0.001) and a positive correlation between PDU score and CI (r = 0.193, p = 0.019) were found, whereas RRI was not correlated with CI (r = 0.131, p = 0.121). The predictive value of RRI for AKI stage 3 was similar between CI-reduced (area under the curve [AUC] 0.761, 95% confidence interval 0.650-0.851, p < 0.001) and CI-maintained (AUC 0.786, 95% confidence interval 0.665-0.878, p < 0.001) patients. Conversely, PDU score could effectively predict AKI stage 3 in CI-reduced patients (AUC 0.872, 95% confidence interval 0.778-0.936, p < 0.001) but not in CI-maintained patients (AUC 0.669, 95% confidence interval 0.544-0.778, p = 0.071). The predictive value of PDU score for AKI stage 3 was statistically different between CI-reduced and CI-maintained patients (p = 0.021).Conclusions: PDU scores could effectively predict AKI stage 3 in CI-reduced patients but not in CI-maintained patients. RRI is a poor predictor of AKI stage 3 in patients with reduced or maintained CI.

Prediction of acute kidney injury: the ratio of renal resistive index to semiquantitative power Doppler ultrasound score-a better predictor?: A prospective observational study.

This study aimed to explore the diagnostic performance of the ratio of renal resistive index (RRI) to semiquantitative power Doppler ultrasound (PDU) score in predicting acute kidney injury (AKI) 3 in critically ill patients.This study was a prospective, observational study that included 101 critically ill patients. RRI and semiquantitative PDU score were measured within 6 hours following admission to the intensive care unit (ICU). The ratio of RRI to PDU (RRI/PDU) was calculated as follows: RRI / PDU. If PDU score was 0, the RRI/PDU was 1. Meanwhile, AKI was defined according to the Kidney Disease Improving Global Outcomes criteria.Median RRI/PDU was 0.234 (0.190, 0.335) in patients with AKI 0-2 and 0.636 (0.411, 0.738) in patients with AKI 3 (P < .001). As assessed by the area under the receiver operator characteristic curves (AUC), RRI/PDU performed best in diagnosing AKI 3 [AUC = 0.935 (95% CI: 0.868-0.974)]. Optimal cuto for RRI/PDU was > 0.37, and the sensitivity and specificity were 90.5% and 90.0%, respectively. In 93 patients, except for 8 patients with a PDU score of 0, the AUC of RRI/PDU [0.938 (95% CI: 0.868-0.977)] was superior to the PDU score (0.905 [95% CI: 0.826-0.956], P = .133), RRI [0.782 (95% CI: 0.684-0.861), P = .016], serum creatinine [0.801 (95% CI: 0.705-0.877), P = .017], or 6 hours AKI stage (0.876 [95% CI: 0.791-0.935], P = .110) in predicting AKI 3 on D5.In our study, RRI, PDU score, RRI/PDU, and 6 hours AKI stage were useful in predicting AKI 3. Furthermore, RRI/PDU may be a better predictor of AKI 3.