Clinical evaluation of emboli removal by integrated versus non-integrated arterial filters in new generation oxygenators

Abstract

Objective: To compare the emboli filtration efficiency of five integrated or non-integrated oxygenator-filter combinations in cardiopulmonary bypass circuits. Methods: Fifty-one adult patients underwent surgery using a circuit with an integrated filtration oxygenator or non-integrated oxygenator with a separate 20 µm arterial line filter (Sorin Dideco Avant D903 + Pall AL20 (n=12), Sorin Inspire 6 M + Pall AL20 (n=10), Sorin Inspire 6M F (n=9), Terumo FX25 (n=10), Medtronic Fusion (n=10)). The Emboli Detection and Classification quantifier was used to count emboli upstream and downstream of the primary filter throughout cardiopulmonary bypass. The primary outcome measure was to compare the devices in respect of the median proportion of emboli removed. Results: One device (Sorin Inspire 6 M + Pall AL20) exhibited a significantly greater median percentage reduction (96.77%, IQR=95.48 – 98.45) in total emboli counts compared to all other devices tested (p=0.0062 – 0.0002). In comparisons between the other units, they all removed a greater percentage of emboli than one device (Medtronic Fusion), but there were no other significant differences. Conclusion: The new generation Sorin Inspire 6 M, with a stand-alone 20 µm arterial filter, appeared most efficient at removing incoming emboli from the circuit. No firm conclusions can be drawn about the relative efficacy of emboli removal by units categorised by class (integrated vs non-integrated); however, the stand-alone 20 µm arterial filter presently sets a contemporary standard against which other configurations of equipment can be judged.