© 2011 Wichtig Editore - ISSN 0391-3988 Int J Artif Organs ( 2011 ; : 4) 374-382 34 374 DOI: 10.5301/IJAO.2011.7749 INTRODUCTION Cannulation, drug administration, blood sampling, and various components of the cardiopulmonary bypass (CPB) circuit are potential sources of gaseous microemboli (GME) during on-pump cardiac surgery (1-3). Introduction of GME into the arterial line of a CPB circuit may lead to cogni- Clinical evaluation of the air removal characteristics of an oxygenator with integrated arterial filter in a minimized extracorporeal circuit Marco C. Stehouwer 1 , Chris Boers 1 , Roel de Vroege 2 , Johannes C. Kelder 3 , Alaaddin Yilmaz 4 , Peter Bruins 5 1 Department of Extracorporeal Circulation, St Antonius Hospital, Nieuwegein - The Netherlands 2 Department of Extracorporeal Circulation, HAGA Hospital, The Hague - The Netherlands 3 Department of Cardiology, St Antonius Hospital, Nieuwegein - The Netherlands 4 Department of Cardiothoracic Surgery, St Antonius Hospital, Nieuwegein - The Netherlands 5 Department of Anesthesiology, Intensive Care and Pain Management, St Antonius Hospital, Nieuwegein - The Netherlands ABSTRACT The use of minimized extracorporeal circuits (MECC) in cardiac surgery is an important measure to in- crease the biocompatibility of cardiopulmonary bypass during coronary artery bypass grafting (CABG). These circuits eliminate volume storage reservoirs and bubble traps to minimize the circuit. However, the reduction in volume may increase the risk of gaseous microemboli (GME). The MECC system as used by our group consists of a venous bubble trap, centrifugal pump, and an oxygenator. To further reduce the risk of introducing GME, an oxygenator with an integrated arterial filter was developed based on the concept of minimal volume and foreign surface. We studied the air removal characteris- tics of this oxygenator with and without integrated arterial filter. The quantity and volume of GME were measured with precision at both the inlet and outlet of the devices. Our results showed that integration of an arterial filter into this oxygenator increased GME reducing capacity from 69.2% to 92%. Moreover, we were able to obtain data on the impact of an arterial filter on the exact size-distribution of GME entering the arterial line. The present study demonstrates that an MECC system and oxygenator with integrated arterial filter significantly reduces the volume and size of GME. The use of an integrated arterial filter in an MECC system may protect the patient from the deleterious effects of CPB and may further improve patient safety. KEY WORDS: Cardiopulmonary bypass, Minimized extracorporeal circuits, Arterial filter, Gaseous microemboli, Safety Accepted: February 5, 2011 ORIGINAL ARTICLE tive decline and adverse outcomes (4, 5). Arterial filters are incorporated into conventional bypass circuits as a safe- guard for gross air and may reduce the number of GME measured in the arterial line (6, 7). A 40 μm arterial filter re- duces the number of GME by 50% to 73%, depending on the GME diameter (8). Gerriets et al (9) even demonstrated a neuroprotective effect by using an arterial filter.