Sustained inflation with 21% versus 100% oxygen during cardiopulmonary resuscitation of asphyxiated newborn piglets - A randomized controlled animal study

Resuscitation. 2020 Oct:155:39-47. doi: 10.1016/j.resuscitation.2020.07.015. Epub 2020 Jul 24.

Abstract

Background: Current neonatal resuscitation guidelines recommend using 100% oxygen during chest compressions (CC), however the most effective oxygen concentration during cardiopulmonary resuscitation remains controversial.

Aim: In term newborn piglets with asphyxia-induced cardiac arrest does 21% oxygen compared to 100% oxygen during resuscitation using CC during sustained inflation (SI; CC + SI) will have a reduced time to return of spontaneous circulation (ROSC).

Intervention and measurements: Twenty-two mixed breed piglets (1-3 days old, 1.7-2.4 kg), were obtained on the day of the experiment and anesthetized, intubated, instrumented, and exposed to 30-min normocapnic hypoxia followed by asphyxia. Piglets were resuscitated using CC + SI and randomized to 21% oxygen (n = 8) or 100% oxygen (n = 8). Heart rate, arterial blood pressure, carotid blood flow, cerebral oxygenation, and respiratory parameters were continuously recorded throughout the experiment.

Main results: Baseline parameters were similar between 21% and 100% oxygen groups. There was no difference in asphyxiation (duration and degree) between groups. Time to ROSC was similar between 21% and 100% oxygen groups: median (interquartile range - IQR) 80 (70-190)sec vs. 90 (70-324)sec, (p = 0.56). There was no significant difference in the rate of ROSC between 21% and 100% oxygen groups: 7/8 (88%) vs. 5/8 (63%), (p = 0.569). All piglets that achieved ROSC survived to four hours post-resuscitation. Hemodynamics and regional perfusion were not significantly different between groups.

Conclusions: In term newborn piglets resuscitated by CC + SI, the use of 21% oxygen resulted in a similar time to ROSC, short-term survival, and hemodynamic recovery compared to 100% oxygen.

Keywords: Asphyxia; Chest compressions; Infants; Neonatal resuscitation; Newborn; Oxygen; Sustained inflation.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Newborn
  • Cardiopulmonary Resuscitation*
  • Disease Models, Animal
  • Hemodynamics
  • Oxygen*
  • Recovery of Function
  • Swine

Substances

  • Oxygen

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