Cardiopulmonary Resuscitation in the Newborn

Abstract

The transition from foetal to extrauterine life is characterized by a series of unique physiologic events: (1) on the alveolar side, the lungs change from a fluid-filled to an air-filled situation, and (2) on the vascular side, pulmonary blood flow increases dramatically, and extrapulmonary shunts (foramen ovale and ductus arteriosus) the initial reverse direction and subsequently close. Such physiologic considerations represent the basis for resuscitative interventions in the newborn. For initial lung expansion, fluid-filled alveoli may require higher ventilation pressure than commonly used in rescue breathing during infancy (ventilation). Physical expansion of the lungs and an increase in alveolar oxygen tension both mediate the decrease in pulmonary vascular resistance and result in an increase in pulmonary blood flow after birth (perfusion). The main goals of resuscitative interventions consist of assuring an adequate ventilation and, consequently, an adequate perfusion during the transition from prenatal to postnatal life. However, it is important to remember that some developmental situations (i.e. prematurity) and/or specific diseases (i.e. meconium aspiration syndrome) may significantly influence pulmonary pathology and resuscitation physiology in the neonate [1].