Cardiac Agents during Neonatal Cardiopulmonary Resuscitation.

BACKGROUND: Epinephrine (adrenaline) is currently the only cardiac agent recommended during neonatal resuscitation. The inability to predict which newborns are at risk of requiring resuscitative efforts at birth has prevented the collection of large, high-quality human data. SUMMARY: Information on the optimal dosage and route of epinephrine administration is extrapolated from neonatal animal studies and human adult and pediatric studies. Adult resuscitation guidelines have previously recommended vasopressin use; however, neonatal studies needed to create guidelines are lacking. A review of the literature demonstrates conflicting results regarding epinephrine efficacy through various routes of access as well as vasopressin during asystolic cardiac arrest in animal models. Vasopressin appears to improve hemodynamic and post-resuscitation outcomes compared to epinephrine in asystolic cardiac arrest animal models. KEY MESSAGES: The current neonatal resuscitation guidelines recommend epinephrine be primarily given via the intravenous or intraosseous route, with the endotracheal route as an alternative if these routes are not feasible or unsuccessful. The intravenous or intraosseous dose ranges between 0.01 and 0.03 mg/kg, which should be repeated every 3-5 min during chest compressions. However, the optimal dosing and route of administration of epinephrine remain unknown. There is evidence from adult and pediatric studies that vasopressin might be an alternative to epinephrine; however, the neonatal data are scarce.

Comparison of positive pressure ventilation devices during compliance changes in a neonatal ovine model.

BACKGROUND: To compare tidal volume (VT) delivery with compliance at 0.5 and 1.5 mL/cmH2O using four different ventilation (PPV) devices (i.e., self-inflating bag (SIB), T-Piece resuscitator, Next Step (a novel Neonatal Resuscitator), and Fabian ventilator (conventional neonatal ventilator) using a neonatal piglet model. DESIGN/METHODS: Randomized experimental animal study using 10 mixed-breed neonatal piglets (1-3 days; 1.8-2.4 kg). Piglets were anesthetized, intubated, instrumented, and randomized to receive positive pressure ventilation (PPV) for one minute with a SIB with or without a respiratory function monitor (RFM), T-Piece resuscitator with or without an RFM, Next Step, and Fabian Ventilator with both compliance levels. Compliance changes were achieved by placing a wrap around the piglets' chest and tightened it. Our primary outcome was targeted VT delivery of 5 mL/kg at 0.5 and 1.5 mL/cmH2O lung compliance. RESULTS: At 0.5 mL/cmH2O compliance, the mean(SD) expired VT with the Next Step was 5.1(0.2) mL/kg compared to the Fabian 4.8(0.5) mL/kg, SIB 8.9(3.6) mL/kg, SIB + RFM 4.5(1.8) mL/kg, T-Piece 7.4(4.3) mL/kg, and T-Piece+RFM 6.4(3.1) mL/kg. At 1.5 mL/cmH2O compliance, the mean(SD) expired VT with the Next Step was 5.2(0.6) mL/kg compared to the Fabian 4.4(0.7) mL/kg, SIB 12.1(5.3) mL/kg, SIB + RFM 9.4(3.9) mL/kg, T-Piece 8.6(1.5) mL/kg, and T-Piece+RFM 6.5 (1.6) mL/kg. CONCLUSION: The Next Step provides consistent VT during PPV, which is comparable to a mechanical ventilator. IMPACT: Current guidelines recommend fixed peak inflation pressure in resuscitation, linked to lung and brain injury. The Next Step Neonatal Resuscitator, a cost-effective device, offers volume-targeted positive pressure ventilation with consistent tidal volumes. With two different compliances, the Next Step Neonatal Resuscitator delivered a consistent tidal volume which was similar to a mechanical ventilator. The Next Step Neonatal Resuscitator outperformed self-inflating bags and T-Pieces in delivering targeted tidal volumes. The Next Step Neonatal Resuscitator could be an alternative ventilation device for neonatal resuscitation.

Comparison of various vasopressin doses to epinephrine during cardiopulmonary resuscitation in asphyxiated neonatal piglets.

BACKGROUND: Current neonatal resuscitation guidelines recommend epinephrine for cardiac arrest. Vasopressin might be an alternative during asphyxial cardiac arrest. We aimed to compare vasopressin and epinephrine on incidence and time to return of spontaneous circulation (ROSC) in asphyxiated newborn piglets. DESIGN/METHODS: Newborn piglets (n = 8/group) were anesthetized, intubated, instrumented, and exposed to 30 min of normocapnic hypoxia, followed by asphyxia and asystolic cardiac arrest. Piglets were randomized to 0.2, 0.4, or 0.8IU/kg vasopressin, or 0.02 mg/kg epinephrine. Hemodynamic parameters were continuously measured. RESULTS: Median (IQR) time to ROSC was 172(103-418)s, 157(100-413)s, 122(93-289)s, and 276(117-480)s for 0.2, 0.4, 0.8IU/kg vasopressin, and 0.02 mg/kg epinephrine groups, respectively (p = 0.59). The number of piglets that achieved ROSC was 6(75%), 6(75%), 7(88%), and 5(63%) for 0.2, 0.4, 0.8IU/kg vasopressin, and 0.02 mg/kg epinephrine, respectively (p = 0.94). The epinephrine group had a 60% (3/5) rate of post-ROSC survival compared to 83% (5/6), 83% (5/6), and 57% (4/7) in the 0.2, 0.4, and 0.8IU/kg vasopressin groups, respectively (p = 0.61). CONCLUSION: Time to and incidence of ROSC were not different between all vasopressin dosages and epinephrine. However, non-significantly lower time to ROSC and higher post-ROSC survival in vasopressin groups warrant further investigation. IMPACT: Time to and incidence of ROSC were not statistically different between all vasopressin dosages and epinephrine. Non-significantly lower time to ROSC and higher post-ROSC survival in vasopressin-treated piglets. Overall poorer hemodynamic recovery following ROSC in epinephrine piglets compared to vasopressin groups. Human neonatal clinical trials examining the efficacy of vasopressin during asphyxial cardiac arrest will begin recruitment soon.