The impact of gasping versus apnea on initial heart rate and response to positive pressure ventilation in the delivery room following interruption of placental blood flow

Abstract

Background: The impact and/or significance of gasping or apnea on cardio-respiratory status at birth remains unclear.

Objectives: The study objectives were to determine in infants presenting with gasping or apnea in the delivery room, initial heart rate (HR), responses to positive pressure ventilation (PPV), time to onset of spontaneous respirations, and the relationship of these responses to 24-hour outcome (death/survival) METHODS: Observation study undertaken in a rural setting involving late preterm and term newborns who gasped (n=126) or were apneic (n=105) at birth and received PPV had HR and respiratory parameters continuously measured and were video recorded.

Results: Apneic (12.3 %) versus gasping infants (5.7 %) were 7.2-fold more likely to die in the first 24 h (p = 0.01) and 2.8-fold more likely to die (p = 0.047) by 7 days. Initial HR was higher in gasping versus apneic infants (122 vs 105 bpm) (p = 0.01). Time to initiate breathing after starting PPV was significantly shorter in gasping versus apneic infants. No differences in applied peak inflation pressure, tidal volume, end tidal CO2, or resuscitation duration were noted. Of infants who died versus survivors, a HR < 100 bpm was observed more often in both gasping and apneic infants (p = 0.01) CONCLUSIONS: Infants who present with gasping versus apnea are less likely to die; apneic infants are more likely to die within the initial 24 h. Gasping versus apneic infants had a higher initial HR, were less likely to have a HR < 100 bmp and initiated spontaneous respiratory effort sooner after PPV. These findings are consistent with experimental and adult observations that suggest gasping appears critical to survival if PPV is initiated in a timely manner.

Keywords: Apnea; Gasping; Heart rate response; Neonatal resuscitation; Positive pressure ventilation; Resuscitation monitor; Tidal Volume.