A new intravascular membrane oxygenator to augment blood gas transfer in patients with acute respiratory failure.

The IVOX (intravascular oxygenator) is an intracorporeal, hollow-fibre membrane oxygenator and carbon dioxide (CO2) removal device. The IVOX is surgically placed into the vena cava via a femoral or jugular venotomy. Oxygen (O2) is pulled through the hollow fibers by a vacuum pump controlled by a flow meter. There is no extracorporeal circulation of blood. Gas exchange occurs as the patient's blood flows over several hundred hollow fibers. Inlet and outlet gas conduits exit a small skin incision for inflow of O2 and outflow of CO2. Studies in sheep and humans show that the IVOX can support approximately 30% of gas exchange requirements. The position of the IVOX in the vena cava does not affect hemodynamics or cause thromboembolic complications. It can remain in place for up to 22 days without affecting hematologic or blood chemistry parameters. The IVOX is currently undergoing clinical trials at selected medical centers in patients with acute respiratory failure.