Development and clinical application of a new membrane oxygenator using a microporous polysulfone membrane

We have developed a new plate-type membrane oxygenator (MO) using a microporous polysulfone membrane. The MO is compact, handy and very easy to set up, and has easy defoaming. The MO is primed with crystalloid; through the cardiotomy reservoir, air exits across the porous membrane and is removed through ports in the membrane oxygenator. Performance and clinical use have shown that the PS oxygenator has a better gas exchange than conventional silicone oxygenators, with appropriate O2/CO2 balance and a capability for controlling oxygen and carbon dioxide separate exchange. The advantage of the MPS membrane is improved blood compatibility, and TABLE 1. BLOOD GAS ANALYSIS DURING PERFUSION Mean +/- SD Range Blood Flow (L/min) 1.56 +/- 0.29 1.04-2.12 Gas Flow (L/min) 1.89 +/- 0.73 0.5-3.0 Gas/Blood Flow Ratio 1.19 +/- 0.38 0.45-1.95 pH venous 7.340 +/- 0.083 7.220-7.443 arterial 7.390 +/- 0.080 7.272-7.507 pCO2 (mm Hg) venous 44.8 +/- 10.8 29.6-65.2 arterial 35.7 +/- 7.1 23.8-51.1 pO2 (mm Hg) venous 46.4 +/- 17.2 26.1-98.8 arterial 276.3 +/- 135.6 66.1-533.4 SO2 (%) venous 71.9 +/- 14.7 35.7-95.6 arterial 98.7 +/- 2.3 91.5-99.9 a larger number of small pores than the MPP membrane. Vapor loss, thought to be typical of microporous membranes, was found to be negligibly small. Use of the PS oxygenator for open heart surgery on 15 pediatric patients proved satisfactory, and in the future the oxygenator may prove useful for prolonged perfusions.