Reduction of circulating microemboli in the subclavian vein of patients undergoing haemodialysis using pre-filled instead of dry dialysers

Background. Chronic microembolization that can be demonstrated by pulsed Doppler ultrasound may give rise to pulmonary side-effects during haemodialysis by direct vessel obstruction, increased complement activation or platelet aggregation. The objective of the present investigation was to study whether the use of pre-filled instead of dry dialysers would help to minimize the number of microemboli. Methods. The study cohort consisted of 23 patients undergoing maintenance haemodialysis. Using a 2 MHz pulsed ultrasound device, the subclavian vein downstream to the dialysis fistula was investigated for 10 min during the dialysis session. The ultrasound examination was performed twice during two successive dialysis sessions, using a pre-filled or a dry dialyser in randomized order. Results. In all patients investigated, numerous micro-embolic signals (MES) could be observed in the subclavian vein. Treatment with pre-filled dialysers was associated with significantly less MES (82 +/- 94) as compared with dry dialysers (268 +/- 296; P = 0.002). Conclusions. In comparison to dry dialysers, the use of pre-filled dialysers leads to a significant reduction in microembolization, which may prevent repeated damage to the pulmonary vasculature and, thus, cause less pulmonary damage.