While mechanical ventilators can assist patients with breathing for short periods of time, they sometimes cause lung damage. The McGowan Institute is working on several devices that help to oxygenate blood before it arrives in the lungs. One version, the Hattler Catheter®, is inserted into a major artery. The Hattler Catheter® has been licensed to the Pittsburgh firm ALung Technologies and is being readied for clinical research studies. Another version, the respiratory assist lung, is worn outside the body, where it passes blood across gas exchange fibers. The respiratory assist lung is meant for critical care emergencies, such as in the treatment of trauma and battlefield wounds.