Delayed Cord Clamping for Congenital Diaphragmatic Hernia

Overview

Congenital diaphragmatic hernia (CDH) is a congenital anomaly associated with a high risk of mortality and need for life-saving interventions such as extracorporeal membrane oxygenation (ECMO), nitric oxide, and vasopressor support. Although infants with CDH experience significant morbidity and mortality starting immediately after birth, high quality evidence informing delivery room resuscitation in this population is lacking. Infants with CDH are at risk for pulmonary hypoplasia and pulmonary hypertension and often experience hypoxemia and acidosis during neonatal transition. The standard approach to DR resuscitation is immediate umbilical cord clamping (UCC) followed by intubation and mechanical ventilation. Animal models suggest that achieving lung aeration prior to UCC results in improved pulmonary blood flow and cardiac function compared with immediate UCC before lung aeration is established. Trials of preterm infants demonstrated that initiating respiratory support prior to UCC is safe and feasible. Because infants with CDH are at high risk for pulmonary hypertension and systemic hypotension, they may benefit from the hemodynamic effects of lung aeration before UCC, namely increased pulmonary blood flow, decreased pulmonary vascular resistance, and improved cardiac output. To date, this approach has not been studied in infants with CDH.

Congenital diaphragmatic hernia (CDH) is a congenital anomaly associated with a high risk of mortality (29%) and need for life-saving interventions such as ECMO (33%), nitric oxide (62%), and vasopressor support (73%).1 Although infants with CDH experience significant morbidity and mortality starting immediately after birth, high quality evidence informing delivery room resuscitation in this population is lacking. Infants with CDH are at risk for pulmonary hypoplasia and pulmonary hypertension and often experience hypoxemia and acidosis during neonatal transition. The standard approach to delivery room (DR) resuscitation is immediate UCC followed by intubation and mechanical ventilation. The goals of this strategy are to immediately recruit and aerate the lung for gas exchange and oxygenation, while simultaneously avoiding gaseous distention of the thoracic gastrointestinal contents. Animal models suggest that achieving lung aeration prior to UCC results in improved pulmonary blood flow and cardiac function compared with immediate UCC before lung aeration is established. Trials of preterm infants demonstrated that initiating respiratory support prior to UCC is safe and feasible. Because infants with CDH are at high risk for pulmonary hypertension and systemic hypotension, they may benefit from the hemodynamic effects of lung aeration before UCC, namely increased pulmonary blood flow, decreased pulmonary vascular resistance, and improved cardiac output. The investigators hypothesize that a sequence of intubation, gentle ventilation, and then umbilical cord clamping will result in improved cardiovascular transition after birth in infants with CDH. To date, this approach has not been studied in infants with CDH. The DING trial will assess the feasibility and safety of this intervention in infants with CDH.