DEVELOPMENT OF A SILICONE HOLLOW-FIBER MEMBRANE-OXYGENATOR FOR ECMO APPLICATION

A new silicone hollow fiber membrane oxygenator for extracorporeal mem brane oxygenation (ECMO) was developed using an ultrathin silicone hol low fiber, with a 300 mu m outer diameter and a wall thickness of 50 m u m. The hollow fibers were mechanically cross-wound on the flow distr ibutor to achieve equal distribution of blood flow without changing th e fiber shape. The housing, made of silicone coated acryl, was 236 mm long with an inner diameter of 60 mm. The surface area was 1.0 m(2) fo r prototype 211, and 1.1 m(2) for prototype 209. The silicone fiber le ngth was 150 mm, and the silicone membrane packing density was 43% for prototype 211 and 36% for prototype 209. Prototype 211 has a priming volume of 208 ml, and prototype 209 has a priming volume of 228 ml. Th e prototype 211 oxygenator demonstrates a gas transfer rate of 120 +/- 5 ml/min (mean +/- SD) for O-2 and 67 +/- 12 ml/min for CO2 under 2 L of blood flow and 4 L of O-2 gas flow. Prototype 209 produced the sam e values. The blood side pressure drop was low compared with the silic one sheet oxygenator (Avecor, 1500ECMO). These results showed that thi s new oxygenator for ECMO had efficiency similar to the silicone sheet oxygenator that has a 50% larger surface area. These results suggest that the new generation oxygenator using an ultrathin silicone hollow fiber possesses sufficient gas transfer performance for long-term extr acorporeal lung support.