So, PDA, or patent ductus arteriosis, causes oxygenated blood to move from the high pressure a order and into the low pressure pulmonary trunk. And this means less oxygen will reach the tissues of that individual. What it also means is more blood will actually flow into the lungs, because if this oxygenated blood is mixing with the deoxygenated blood, the influx of blood into the pulmonary system will be greater. And that will put more stress on the lungs. It will increase the pressure inside the lungs. And what that means is that feed, if that person will have more difficulty breathing as a result of the high pressure inside the lungs.