Carotid Artery Flow Time Measured by Point-of-Care Ultrasound Correlates with Volume Changes in Pediatric Hemodialysis Patients

Abstract

Carotid artery flow time corrected for heart rate (CFTc) correlates with intravascular volume changes in adults but has not been studied adequately in the pediatric population. We studied how fluid status changes correlate with CFTc in pediatric patients undergoing hemodialysis. This prospective observational study involved pediatric patients aged 5–18 y undergoing chronic hemodialysis at a tertiary care children’s hospital in the United States. We measured CFTc by point-of-care ultrasound before and after each hemodialysis session, including passive leg raise. One hundred sixty-eight CFTc measurements were obtained from a total of 21 patient encounters. Post-dialysis CFTc decreased by 21.7 ms (95% confidence interval: 12.3–31.0) (p < 0.001). Pre- and post-dialysis ∆CFTc measurements were proportionally correlated with volume removed in dialysis adjusted for weight (mL/kg) (R2 = 0.224, p = 0.03). There was no significant change in mean CFTc with passive leg raise before or after hemodialysis. In children on hemodialysis, changes in CFTc were moderately correlated with decrease in intravascular volume after hemodialysis.