Development of a Paracorporeal Respiratory Assist Lung (PRAL)

摘要

DEVELOPMENT OF A PARACORPOREAL RESPIRATORY ASSIST LUNGRobert G. Svitek, PhDUniversity of Pittsburgh, 2006A Paracorporeal Respiratory Assist Lung (PRAL) was developed for supplemental gasexchange to allow the native lungs of acute lung failure patients time to heal. The deviceconsisted of a rotating annular microporous hollow fiber membrane bundle. The rotationaugmented the gas exchange efficiency of the device at constant flowrate therebyuncoupling gas exchange and flowrate. The rotating fibers also enabled the PRAL topump the blood without the need for an additional pump or arterial cannulation. Aprototype was manufactured with an overall surface area of 0.42 m2, and CO2 removalrates were 101 ml/min at a blood flowrates of 0.75 L/min. When rotated at 1500 RPM,CO2 removal increased by 92 % and O2 transfer increased by 88% over the stationarybundle during an in vitro bovine blood study. The pumping of the rotating fiber bundlewas assessed, and at 1500 RPM the PRAL generated 750 ml/min against 52 mmHgpressure in water. Hemolysis of the device was assessed using in vitro bovine bloodfrom a slaughterhouse. Plasma free hemoglobin levels were higher than the control,and we found that the roughness of the rotating fibers was the cause of much of theblood trauma.