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Abstract

In our recent study, “Efficacy of Intravenous and Endotracheal Epinephrine during Neonatal Cardiopulmonary Resuscitation in the Delivery Room,”1Halling C. Sparks J.E. Christie L. Wyckoff M.H. Efficacy of intravenous and endotracheal epinephrine during neonatal cardiopulmonary resuscitation in the delivery room.J Pediatr. 2017; https://doi.org/10.1016/j.jpeds.2017.02.024Abstract Full Text Full Text PDF PubMed Scopus (42) Google Scholar we raise concerns that the currently recommended dosing recommendations for both intravenous and endotracheal (ET) epinephrine frequently needed to be repeated before return of spontaneous circulation (ROSC) is achieved. We also demonstrated that the vast majority of infants who achieved ROSC did so after receiving an intravenous (IV) dose of epinephrine even if prior ET doses were provided. The recent study by Vali et al,2Vali P. Chandrasekharan P. Rawat M. Gugino S. Koenigsknecht C. Helman J. et al.Evaluation of timing and route of epinephrine in a neonatal model of asphyxial arrest.J Am Heart Assoc. 2017; 6Crossref PubMed Scopus (38) Google Scholar which used a perinatal asphyxia cardiac arrest lamb model to mimic newborn physiology, provides valuable evidence that a higher IV epinephrine dose (0.03 mg/kg) is superior at achieving ROSC compared with the lower dose of 0.01 mg/kg. Vali's study demonstrates lower peak plasma concentrations of epinephrine following ET administration compared with IV administration, which once again raises the question of how efficacious the ET route is at delivering epinephrine into the newborn's circulation. In answer to the questions raised by Vali et al, we used the lower starting dose of 0.01 mg/kg of IV epinephrine because at the time (January 2006-July 2014), there was no evidence to suggest that starting with a higher dose was more beneficial, it was within the recommended range of the American Academy of Pediatrics Neonatal Resuscitation Program Guidelines, and we were operating on the principal of using the lowest effective dose possible to minimize harmful side effects (not knowing that the efficacy was in question). Out of concern that 0.01 mg/kg may not be sufficient at achieving ROSC as demonstrated by our study, we have since increased the starting IV epinephrine dose to 0.2 mg/kg, which is still within the recommended range. We are collecting data prospectively to determine if this will improve clinical efficacy. In our study, we analyzed 50 infants who received cardiopulmonary resuscitation, including epinephrine, in the delivery room. Seventy-six percent ultimately achieved ROSC. Of the 12 infants who did not achieve ROSC, 5 infants received 3 doses of IV epinephrine (4 initially received ET epinephrine), 6 infants received 4 doses of IV epinephrine (3 initially received ET epinephrine), and 1 infant received 5 doses of IV epinephrine without prior ET dosing before cessation of resuscitation efforts. Thirty-seven (74%) infants were initially asystolic and 13 (26%) were initially bradycardic. The Figure (available at www.jpeds.com) shows the responses of the individual infants who were bradycardic compared with those who were asystolic. Our study concluded that additional studies are indicated to determine the efficacy, safety, and optimal dosing of IV and ET epinephrine and to help determine whether the ET route of epinephrine delivery has a continued role in neonatal resuscitation.1Halling C. Sparks J.E. Christie L. Wyckoff M.H. Efficacy of intravenous and endotracheal epinephrine during neonatal cardiopulmonary resuscitation in the delivery room.J Pediatr. 2017; https://doi.org/10.1016/j.jpeds.2017.02.024Abstract Full Text Full Text PDF PubMed Scopus (42) Google Scholar We believe that the recent study by Vali et al was an important first step needed to help answer these essential questions. In quest of epinephrine's optimal route and dose in neonatal cardiopulmonary resuscitation—are we there yet?The Journal of PediatricsVol. 189PreviewThe infrequent need for the use of epinephrine during neonatal resuscitation, coupled with our inability to anticipate consistently which newborns are at greatest risk of requiring extensive resuscitation, explains the ongoing lack of high-quality evidence supported by large, randomized clinical trials on this subject. Therefore, large retrospective studies provide the greatest level of evidence on the efficacy of epinephrine during neonatal resuscitation. Full-Text PDF