Respiratory and Cardiovascular Support in the Delivery Room

Aeration of the lungs following delivery is the key to successful transition to newborn life. Clearance of lung fluid enables the onset of gas exchange and initiates the cardiovascular changes, leading to an increase in pulmonary blood flow and maintenance of systemic cardiac output. Most infants make the transition without interventions but up to 10% require some assistance. In some cases, the need for resuscitation may be anticipated, but others with no risk factors require help. Hence, trained personnel must be available at every delivery to assess the newborn and initiate resuscitation when necessary. Nonvigorous and preterm newborns should be taken to a radiant warmer for assessment. Care should be taken to maintain the infant’s temperature in the normal range. Effective ventilation is the single most important action to stabilize a compromised newborn infant. This may be achieved with a number of devices. Whichever is chosen, it is important that the user is proficient at using and troubleshooting that device. The best indicator of effective ventilation is a rapid rise in heart rate. Airway obstruction and mask leak are the most common causes of ineffective ventilation. Current guidelines recommend starting resuscitation with air for term and near-term infants and 30% oxygen for preterm infants. Pulse oximetry may be used to titrate oxygen therapy to achieve oxygen saturation levels similar to those seen in healthy term newborns. Cardiac compressions are recommended for infants with heart rates persistently lower than 60 beats/min. Compressions should be centered over the lower third of the sternum and delivered to a depth of one-third the anteroposterior diameter of the chest. A compression-to-ventilation ratio of 3:1 is currently recommended. Medications may be required in the setting of very severe asphyxia. Epinephrine is useful for asystole or agonal bradycardia because it improves diastolic blood pressure and hence coronary perfusion.