Chest Compressions and Ventilation in Delivery Room Resuscitation

Abstract

The purpose of chest compressions (CCs) is to generate blood flow to vital organs in a state in which the myocardium is unable to produce forward blood flow by internal pump mechanisms. In newborn infants requiring CCs in the delivery room, the most frequent cause of myocardial compromise is energy depletion due to hypoxia. Hypoxemia and the accompanying hypercarbia and metabolic acidosis (ie, asphyxia) causes systemic vasodilation, further compromising perfusion pressure. Hence, in neonatal cardiopulmonary resuscitation (CPR), the focus is on both reversing hypoxia and enhancing coronary and systemic perfusion pressure. There are limited clinical data to support a recommendation for how CC and ventilation should be optimized for this purpose in the newborn. However, studies in animal models and manikins suggest that using a compression-to-ventilation ratio (C:V) of 3:1 and delivering compressions during a pause in ventilation results in improved ventilation and reversal of hypoxia. Use of the 3:1 ratio, compared with higher C:V ratios, also results in more effective CC during prolonged CPR. A C:V ratio of 3:1 is perceived as more exhausting to perform than higher ratios, and a high CC rate, which may be beneficial, cannot be achieved with pauses in CCs for the delivery of ventilation. Continuous CCs and asynchronous ventilation have been shown to have improved outcomes in adults and older children after cardiac arrest, and current evidence suggests that it is as good as a 3:1 C:V ratio in neonatal resuscitation. Further studies are needed and should focus on the optimal resuscitative approach in neonatal CPR.