Related Experiment Videos
Variable flow Doppler for hemodialysis access evaluation: theory and clinical feasibility
W F Weitzel1, J M Rubin, R D Swartz
1Department of Internal Medicine, University of Michigan Medical Center, Ann Arbor 48109-0364, USA.
ASAIO Journal (American Society for Artificial Internal Organs : 1992)
|February 10, 2000
Summary
A novel variable flow (VF) Doppler technique accurately measures hemodialysis access blood flow. This method detects access pathology and predicts thrombosis risk without complex calculations or line reversals.
Area of Science:
- Nephrology
- Vascular Surgery
- Medical Imaging
Background:
- Vascular access thrombosis is a significant complication for hemodialysis patients.
- Reduced access blood flow is a key predictor of access failure.
- Existing methods for assessing access flow can be complex or invasive.
Purpose of the Study:
- To introduce and validate a new method for determining access volume flow using Doppler ultrasound.
- To assess the clinical feasibility of the variable flow (VF) Doppler technique.
- To identify aberrant flow patterns indicative of access pathology.
Main Methods:
- Utilized Doppler ultrasound signal downstream from the arterial needle.
- Employed a variable hemodialysis blood pump flow rate.
- Compared VF Doppler technique with duplex volume flow estimates in 18 accesses (16 patients).
Main Results:
- Demonstrated a strong correlation (0.83, p < 0.0001) between VF Doppler and duplex methods.
- Observed aberrant flow patterns, including reversed diastolic flow, in accesses with lower blood flow rates.
- Linked severe reversed diastolic flow to access recirculation.
Conclusions:
- The VF Doppler technique is a clinically feasible method for determining access blood flow.
- This technique does not require access cross-sectional area or line reversal.
- VF Doppler provides valuable insights into aberrant flow patterns, aiding in the prediction of access failure.