#5179 LESS MICROBUBBLES ENTERED THE PATIENTS USING THE VENOUS CHAMBER EMBOLESS DURING HAEMODIALYSIS

Abstract

Abstract Background and Aims The extracorporeal circuit (ECC) enables haemodialysis (HD) of patients. Air contamination of the blood appears when it passes the ECC and consequently microbubbles (MBs) enter to the patient [1]. MBs were verified at autopsy of HD patients and covered by clots as microemboli deposited within tissue from lungs, heart and brain [2]. A venous chamber is inserted in the ECC to reduce contamination of MBs. However, chambers in clinical use have limited capacity to eliminate MBs from entering the return bloodline. In an in vitro preclinical study the Emboless chamber showed best results compared to common models in clinical use; the best of those was for Fresenius 5008 [3]. We compared if the venous chamber Emboless differs in capacity to limit MB exposure from the original venous chamber of Fresenius 5008 (F5008). Method Thirty-eight HDs were performed as 19 paired HD sessions. Eleven patients were included. Venous chambers used were either F5008 or Emboless, in a randomised order. Dialyzers, blood-pump speed, HD or HDF and ultrafiltration was kept similar between the pairs. Microbubbles were measured at the ‘Inlet’ and ‘Outlet’ of the venous chamber with an ultrasound device adjusted for HD (hil mode, BCC200, GAMPT). Measurements were made for MBs between all sizes 20µm-500µm diameter. If HDF was performed the first 30min measured were by HD and the subsequent 30min by HDF (extended time if less than 1000 detected inlet MBs). The percentage of change in ‘Outlet’ versus ‘Inlet’ counts were compared (paired Wilcoxon test). Total reduction was -100% while increase of MBs (worsened) caused unlimited (+) percentage. If a diameter was without counts it was not included in the analysis. Results The median overall change of MBs were for F5008 −33% (mean −20 ±76%, N = 8544) and for Emboless -69% (mean -56 ±54%, N = 8402; and pairwise N = 8093, p<0.001). The Table 1 shows more results. Conclusion Less MBs and subsequently less microemboli entered to the patient using the EmbolessTM compared to using the Fresenius 5008 venous chamber during haemodialysis. Considering our previous autopsy studies2 this supports less tissue damage of the patients using EmbolessTM.