Persistent pulmonary hypertension of the newborn.
In utero, fetal pulmonary vascular resistance (PVR) is high, but rapidly falls after birth. Expansion of the lungs, increase in oxygenation, release of vasoactive mediators, growth factors and remodeling of the vascular wall, all contribute to the reduction in PVR. Persistent pulmonary hypertension of the newborn (PPHN) is defined as a failure of the pulmonary vasculature to relax at birth, resulting in hypoxemia. PPHN is in fact a variety of disorders that have a common presentation. Some of the pathophysiological mechanisms and the therapeutic approaches are discussed below.
Thérèse
Perreault
P
Montreal Children's Hospital, McGill University, 2300 Tupper Street, Montreal, Quebec, Canada H3H 1P3. therese.perreault@muhc.mcgill.ca
D000280:Administration, Inhalation; D019332:Endothelin-1 / Q000378:metabolism*; D045462:Endothelium-Dependent Relaxing Factors / Q000008:administration & dosage / Q000627:therapeutic use; D006801:Humans; D007231:Infant, Newborn; D009569:Nitric Oxide / Q000008:administration & dosage / Q000378:metabolism / Q000627:therapeutic use*; D010547:Persistent Fetal Circulation Syndrome / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology; D011379:Prognosis; D011669:Pulmonary Wedge Pressure / Q000502:physiology*; D014661:Vasoconstriction / Q000502:physiology
D019332:Endothelin-1; D045462:Endothelium-Dependent Relaxing Factors; D009569:Nitric Oxide