The effects of zwitterionic polymer coatings and nitric oxide on artificial lungs

Abstract

While lung transplantation remains the last resort for the patients with end-stage lung failure (LF), it is limited by the shortage of donor lungs. There is growing interest in long-term artificial lungs (AL), that can be used not only as a bridge therapy but also as a destination therapy for the patients with advanced LF. Surface-induced coagulation limits lifetime of AL. Zwitterionic polymer coating reduces protein fouling by electrostatically attracting a layer of water molecules that repels proteins. The coating over artificial lung surfaces may reduce contact activation of the coagulation cascade and slow clot formation. Nitric oxide (NO) diffuses into platelet cells, suppresses expression of the platelet receptors, and prevents platelets from being activated. We will discuss our rabbit studies for evaluating the effects of the coating and NO. The studies suggested that combined use of the coating and NO reduced clotting activity and clot weight.