What is the optimal initial dose of epinephrine during neonatal resuscitation in the delivery room?

A Novel Method for Administering Epinephrine during Neonatal Resuscitation

OBJECTIVE

This study aimed to determine if prefilled epinephrine syringes will reduce time to epinephrine administration compared with conventional epinephrine during standardized simulated neonatal resuscitation.

STUDY DESIGN

Timely and accurate epinephrine administration during neonatal resuscitation is lifesaving in bradycardic infants. Current epinephrine preparation is inefficient and error-prone. For other emergency use drugs, prefilled medication syringes have decreased error and administration time. Twenty-one neonatal intensive care unit nurses were enrolled. Each subject engaged in four simulated neonatal resuscitation scenarios involving term or preterm manikins using conventional epinephrine or novel prefilled epinephrine syringes specified for patient weight and administration route. All scenarios were video-recorded. Two investigators analyzed video recordings for time to epinephrine preparation and administration. Differences between conventional and novel techniques were evaluated using the Wilcoxon Signed Rank Tests.

RESULTS

Twenty-one subjects completed 42 scenarios with conventional epinephrine and 42 scenarios with novel prefilled syringes. Epinephrine preparation was faster using novel prefilled epinephrine syringes (median = 17.0 s, interquartile range [IQR] = 13.3-22.8) compared with conventional epinephrine (median = 48.0 s, IQR = 40.5-54.9, n = 42, z = 5.64, p < 0.001). Epinephrine administration was also faster using novel prefilled epinephrine syringes (median = 26.9 s, IQR = 22.1-33.2) compared with conventional epinephrine (median = 57.6 s, IQR = 48.8-66.8, n = 42, z = 5.63, p < 0.001). In a poststudy survey, all subjects supported the clinical adoption of prefilled epinephrine syringes.

CONCLUSION

During simulated neonatal resuscitation, epinephrine preparation and administration are faster using novel prefilled epinephrine syringes, which may hasten return of spontaneous circulation and be lifesaving for bradycardic neonates in clinical practice.

KEY POINTS

· Currently, epinephrine administration in neonatal resuscitation is inefficient and error prone.. · Prefilled epinephrine syringes hasten medication administration in simulated neonatal resuscitation.. · Clinical use of prefilled epinephrine syringes may be lifesaving for bradycardic neonates..

Is epinephrine effective during neonatal resuscitation?

In the original research article published in Pediatric Research, Anderson et al provide valuable data from a placebo-controlled randomized trial on epinephrine in 12-hour-old piglets in cardiac arrest. In this commentary, we discuss briefly the existing evidence supporting use of epinephrine during neonatal resuscitation.

Updates for the Neonatal Resuscitation Program and Resuscitation Guidelines

Although most newborns require no assistance to successfully transition to extrauterine life, the large number of births each year and limited ability to predict which newborns will need assistance means that skilled clinicians must be prepared to respond quickly and efficiently for every birth. A successful outcome is dependent on a rapid response from skilled staff who have mastered the cognitive, technical, and behavioral skills of neonatal resuscitation. Since its release in 1987, over 4.5 million clinicians have been trained by the American Heart Association and American Academy of Pediatrics Neonatal Resuscitation Program®. The guidelines used to develop this program were updated in 2020 and the Textbook of Neonatal Resuscitation, 8th edition, was released in June 2021. The updated guidelines have not changed the basic approach to neonatal resuscitation, which emphasizes the importance of anticipation, preparation, teamwork, and effective ventilation. Several practices have changed, including the prebirth questions, initial steps, use of electronic cardiac monitors, the initial dose of epinephrine, the flush volume after intravascular epinephrine, and the duration of resuscitation with an absent heart rate. In addition, the program has enhanced components of the textbook to improve learning, added new course delivery options, and offers 2 course levels to allow learners to study the material that is most relevant to their role during neonatal resuscitation. This review summarizes the recent changes to the resuscitation guidelines, the textbook, and the Neonatal Resuscitation Program course.

Inadequate Bioavailability of Intramuscular Epinephrine in a Neonatal Asphyxia Model

BACKGROUND

Over half a million newborn deaths are attributed to intrapartum related events annually, the majority of which occur in low resource settings. While progress has been made in reducing the burden of asphyxia, novel approaches may need to be considered to further decrease rates of newborn mortality. Administration of intravenous, intraosseous or endotracheal epinephrine is recommended by the Newborn Resuscitation Program (NRP) with sustained bradycardia at birth. However, delivery by these routes requires both advanced skills and specialized equipment. Intramuscular (IM) epinephrine may represent a simple, low cost and highly accessible alternative for consideration in the care of infants compromised at birth. At present, the bioavailability of IM epinephrine in asphyxia remains unclear.

METHODS

Four term fetal lambs were delivered by cesarean section and asphyxiated by umbilical cord occlusion with resuscitation after 5 min of asystole. IM epinephrine (0.1 mg/kg) was administered intradeltoid after 1 min of positive pressure ventilation with 30 s of chest compressions. Serial blood samples were obtained for determination of plasma epinephrine concentrations by ELISA.

RESULTS

Epinephrine concentrations failed to increase following administration via IM injection. Delayed absorption was observed after return of spontaneous circulation (ROSC) in half of the studies.

CONCLUSIONS

Inadequate absorption of epinephrine occurs with IM administration during asphyxial cardiac arrest, implying this route would be ineffective in infants who are severely compromised at birth. Late absorption following ROSC raises concerns for risks of side effects. However, the bioavailability and efficacy of intramuscular epinephrine in less profound asphyxia may warrant further evaluation.

Resuscitation 2020: Proceedings From the NeoHeart 2020 International Conference

Resuscitation guidelines are developed and revised by medical societies throughout the world. These guidelines are increasingly based on evidence from preclinical and clinical research. The International Liaison Committee on Resuscitation reviews evidence for each resuscitation practice and provides summary consensus statements that inform resuscitation guideline committees. A similar process is used for different populations including neonatal, pediatric, and adult resuscitation. The NeoHeart 2020 Conference brought together experts in resuscitation to discuss recent evidence and guidelines for resuscitation practices. This review summarizes the main focus of discussion from this symposium.

Effect of a Larger Flush Volume on Bioavailability and Efficacy of Umbilical Venous Epinephrine during Neonatal Resuscitation in Ovine Asphyxial Arrest

The 7th edition of the Textbook of Neonatal Resuscitation recommends administration of epinephrine via an umbilical venous catheter (UVC) inserted 2-4 cm below the skin, followed by a 0.5-mL to 1-mL flush for severe bradycardia despite effective ventilation and chest compressions (CC). This volume of flush may not be adequate to push epinephrine to the right atrium in the absence of intrinsic cardiac activity during CC. The objective of our study was to evaluate the effect of 1-mL and 2.5-mL flush volumes after UVC epinephrine administration on the incidence and time to achieve return of spontaneous circulation (ROSC) in a near-term ovine model of perinatal asphyxia induced cardiac arrest. After 5 min of asystole, lambs were resuscitated per Neonatal Resuscitation Program (NRP) guidelines. During resuscitation, lambs received epinephrine through a UVC followed by 1-mL or 2.5-mL normal saline flush. Hemodynamics and plasma epinephrine concentrations were monitored. Three out of seven (43%) and 12/15 (80%) lambs achieved ROSC after the first dose of epinephrine with 1-mL and 2.5-mL flush respectively (p = 0.08). Median time to ROSC and cumulative epinephrine dose required were not different. Plasma epinephrine concentrations at 1 min after epinephrine administration were not different. From our pilot study, higher flush volume after first dose of epinephrine may be of benefit during neonatal resuscitation. More translational and clinical trials are needed.