An inflatable percutaneous oxygenator has an inflatable balloon suitable for insertion into a blood vessel. Oxygen is circulated through a number of gas-permeable passageways (such as hollow gas-permeable fibers) adjacent to the balloon surface to permit diffusion of oxygen and carbon dioxide between the blood vessel and the passageways. Pulsatile flow can be used to increase the rate of cross-diffusion of gases. A pump is used to alternately expand and contract the balloon. This causes movement of the passageways within the blood vessel to minimize streaming or channeling of the blood flow around the oxygenator, maximizes turbulence in the blood stream, and therefore maximizes diffusion of gases. In one alternative embodiment, the balloon is made of a gas-permeable material and is inflated with oxygen to supplement cross-diffusion of gases with the bloodstream. An external connector with lumens supplies a flow of oxygen to the passageways, exhausts gas from the passageways, and allows inflation and deflation of the balloon by the pump. In one alternative embodiment the balloon has a number of chambers separated by constrictions that restrict the flow of gases between the chambers. This results in a relative phase shift in the inflation and deflation of the balloon chambers to provide peristaltic motion to the balloon.

Inflatable percutaneous oxygenator

A method and apparatus for the in vivo oxygenation of blood without using or disturbing the patient's lungs. The apparatus comprises a plurality of small diameter gas permeable tubes connected to headers at each end. The headers in turn are connected on one end to a source of oxygen rich gas and on the other end to an exhaust means. The apparatus is positioned within the circulatory system of a patient. Particularly, an incision is made in the patient's femoral or iliac vein and the apparatus is threaded through the venae cavae and eventually out an incision in the patient's jugular vein. Both headers are positioned so that a source of oxygen rich gas can be attached and the gas circulated through the device.

Apparatus and method for in vivo extrapulmonary blood gas exchange

Periodic venting of MABR lumen allows high removal rates and high gas-transfer efficiencies.

An extracorporeal blood oxygenation device having a sealed casing containing a bundle comprised of a plurality of gas permeable tubes for efficient gas transfer. The bundle is woven from tubes having at least two different sizes, at least the smaller diameter tubes being gas permeable. The tubes are relatively non-thrombogenic and are open at each end to an enclosed annular chamber having attached input and output fittings. Oxygen-rich gas flows into one annular chamber through an input fitting before flowing through the gas permeable tubes. Venous blood to be oxygenated is introduced into the sealed casing directly into the center of the bundle for dispersement radially outward through the bundle and across the gas permeable tubes wherein the blood comes in contact with the membrane surface of the gas permeable tubes and exchanges carbon dioxide for oxygen across that surface before being collected from around the perimeter of the bundle for return to the patient.

K. Nakano

Papers

Augmentation of gas transfer with pulsatile flow in the coiled tube membrane oxygenator design.

Compact oxygenator design with curved tubes wound in weaving patterns.

Effect of pulsatile blood flow on oxygen transport in serpentine oxygenators