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Acute kidney injury in children undergoing cardiac surgery: predictive value of kidney arterial Doppler-based
Fabiane M De Souza1, Aline V De Carvalho1, Isabel S Ferraz1
1Pediatric Intensive Care Unit, Department of Pediatrics, Clinics Hospital of the State University of Campinas (UNICAMP), 126, Tessália Vieira de Camargo Street, Campinas, SP, 13083-887, Brazil.
Insights
Point-of-care kidney Doppler ultrasound effectively predicts acute kidney injury (AKI) in critically ill children after cardiac surgery. Renal resistive index and pulsatility index show high accuracy, offering a promising non-invasive tool for early AKI detection.
Area of Science:
- Pediatric Nephrology
- Critical Care Medicine
- Medical Imaging
Background:
- Acute kidney injury (AKI) is a significant complication in critically ill children, associated with poor outcomes.
- Cardiac surgery in children poses a risk for developing AKI.
- Early prediction of AKI is crucial for timely intervention and improved patient management.
Purpose of the Study:
- To evaluate the effectiveness of point-of-care kidney Doppler ultrasonography in predicting AKI in pediatric patients post-cardiac surgery.
- To assess the diagnostic performance of renal resistive index (RRI) and renal pulsatility index (RPI) in identifying severe AKI.
Main Methods:
- Prospective study involving 58 children undergoing cardiac surgery.
- Kidney Doppler ultrasound performed within 24 hours post-surgery, measuring RRI and RPI.
- AKI diagnosis based on Kidney Disease Improving Global Outcome (KDIGO) criteria, with primary outcome of severe AKI on day 3.
Main Results:
- AKI was diagnosed in 13 patients by day 3, with 11 classified as severe.
- RRI demonstrated high predictive accuracy for AKI (AUC 0.83), with an optimal cutoff of 0.85.
- RPI also showed strong predictive capability (AUC 0.81), with an optimal cutoff of 1.95. Both indices had high negative predictive values.
Conclusions:
- Kidney Doppler ultrasound, utilizing RRI and RPI, is a promising non-invasive tool for predicting AKI in children following cardiac surgery.
- These Doppler-based variables correlate with estimated GFR and furosemide dosage, suggesting clinical relevance.
- Point-of-care ultrasonography can aid in the early identification of AKI, potentially improving patient outcomes.
Background:
Acute kidney injury (AKI) is a common condition in critically ill children and is associated with increased morbidity and mortality. This study aimed to assess the performance of point-of-care ultrasonography to predict AKI in children undergoing cardiac surgery.
Methods:
In this prospective study, consecutive children underwent kidney Doppler ultrasound examination within 24 h following cardiac surgery, and an experienced operator obtained both renal resistive index (RRI) and renal pulsatility index (RPI). AKI was defined by the Kidney Disease Improving Global Outcome (KDIGO) criteria. The primary outcome was the diagnosis of severe AKI (KDIGO stage 2 or 3) on day 3.
Results:
A total of 58 patients were included. Median age and weight were 12.9 months (IQR 6.0-37.9) and 7.36 kg (IQR 5.19-11.40), respectively. On day 3, 13 patients were classified as having AKI, of which 11 were severe. RRI could effectively predict AKI (area under the ROC curve [AUC] 0.83, 95% CI 0.71-0.92; p < 0.001) as well as RPI (AUC 0.81, 95% CI 0.69-0.90; p < 0.001). The optimal cutoff value for RRI was 0.85 (sensitivity, 73%; specificity, 83%; positive predictive value [PPV], 50%; and negative predictive value [NPV], 93%), while for RPI was 1.95 (sensitivity, 73%; specificity, 78%; PPV, 44%; and NPV, 92%). Similar results were found in the analysis for prediction on day 5. Significant correlations were found between Doppler-based variables and estimated GFR and furosemide dose on day 3.
Conclusions:
Kidney Doppler ultrasound may be a promising tool for predicting AKI in children undergoing cardiac surgery.
