children s health issues
Persistent Pulmonary Hypertension of the Newborn
Introduction
Persistent pulmonary hypertension of the newborn is a serious disorder in which the arteries to the lungs remain narrowed (constricted) after delivery, thus limiting the amount of blood flow to the lungs and therefore the amount of oxygen in the bloodstream. This disorder causes severe trouble breathing (respiratory distress) in full-term or postterm newborns. Breathing is rapid, and the skin and/or lips may be bluish or may be pale and grayish. The diagnosis is confirmed by an echocardiogram. Treatment involves opening (dilating) the arteries to the lungs by giving high concentrations of oxygen, often while supporting the newborn’s breathing with a ventilator. To help dilate the arteries in the lungs, sometimes nitric oxide is added to the gas that the newborn is breathing. Extracorporeal membrane oxygenation is sometimes used in the most severe cases. (See also Overview of General Problems in Newborns .) Normally, the blood vessels to the fetus's lungs are tightly constricted before birth. The lungs do not need much blood flow before birth because the placenta rather than the lungs eliminates carbon dioxide and transports oxygen to the fetus. However, immediately after birth, the umbilical cord is cut and the newborn’s lungs must take over the role of oxygenating the blood and removing carbon dioxide. To achieve this process, it is necessary for the fluid filling the air sacs (alveoli) in the lungs to be replaced by air and for the pulmonary arteries, which bring blood to the lungs, to widen (dilate) so that an adequate amount of blood flows through the lungs to be oxygenated. 