Change in access blood flow over time predicts vascular access thrombosis

Area of Science:

• Nephrology
• Vascular Surgery
• Medical Devices

Background:

• Vascular access thrombosis is a major complication for chronic hemodialysis patients, causing significant healthcare costs and hospitalizations.
• Low vascular access blood flow (<800 ml/min) is a known risk factor for thrombosis.
• The study investigates if a time-dependent decrease in blood flow is a better predictor of thrombosis, particularly in accesses with initially higher flows.

Purpose of the Study:

• To determine if a time-dependent decrease in vascular access blood flow predicts thrombosis in chronic hemodialysis patients.
• To assess the predictive value of blood flow changes, especially in accesses with flows >800 ml/min, for identifying critical stenosis.

Main Methods:

• Prospective study of 95 vascular accesses in 91 chronic hemodialysis patients over 18 months.
• Vascular access blood flow measured every six months using ultrasound dilution technique.
• Thrombotic events were systematically recorded throughout the study periods.

Main Results:

• 34 thrombotic events occurred in 95 accesses during the study.
• Accesses that thrombosed showed a 22% and 41% decrease in blood flow over two periods, versus 4% drop and 15% increase in non-thrombosed accesses.
• A >35% decrease in blood flow correlated with a 13.6-fold increased risk of thrombosis.

Conclusions:

• A significant decrease (>15%) in vascular access blood flow is associated with a high risk of thrombosis.
• Serial measurements of vascular access blood flow effectively predict future access thrombosis.
• Monitoring blood flow changes can help identify patients at risk for vascular access complications.