Fiber manufacturing, membrane classification, and winding technologies associated with membrane oxygenators

Fiber bundling refers to the process of winding hollow polypropylene fibers onto the central core of a membrane oxygenator. Identifying the various bundling techniques serves to facilitate the clinician's understanding of unique device characteristics and the subsequent manufacturing process. This technical information has been voluntarily provided by the product managers and engineers of current membrane manufacturers. Currently the industry employs four primary bundling techniques: single strand, mat configuration, tape and helical. Single strand wraps one fiber at a time, up and down a central core to create the fiber bundle. A modification of the single strand technique is the single strand multi toe, where multiple fibers are wound at a time. Mat technology wraps a large, woven sheet consisting of uniformly placed fibers and spacing filaments, around the oxygenator core. A modification is the double mat, where two sheets of fibers oriented at a specific bias to each other, are wrapped to yield a fiber bundle. Tape technology involves evenly spaced fibers, 5 to 10 fibers wide, wrapped up and down the length of the core. Helical utilizes a spacing filament that is spiraled around each individual fiber and then around the core of the device.