Arterial oxygen saturation and heart rate in term newborn in the first hour after birth

The pulse oximeter has been useful in the cardiorespiratory evaluation of the newborn.

To assess arterial oxygen saturation (SpO2) and heart rate (HR) in newborns in the first 60 minutes after birth.

Prospective observational study in healthy term newborns, delivered vaginally or by cesarean section, with maternal bonding, carried out at sea level. A continuous post- ductal SpO2 and HR record were obtained from minute 1 to 10 after birth, and then at 15, 30 and 60 minutes. The SpO2 and HR were measured with a Nellcor pulse oximeter. The software Stata v.14 was used for the statistical analysis.

324 healthy term newborns that met the inclusion criteria were included, of which 160 born vaginally and 164 by cesarean section. The SpO2 increased progres sively from minute 1 (58.7%) to minute 10 (94.5%). Newborns delivered vaginally had a significantly higher SpO2 until minute 10 after birth than those born by cesarean section (p < 0.001). In newborns delivered vaginally, HR was significantly higher in the first two minutes after birth, and then from minute 10 to 60 (p < 0.003). There were no differences by gender in SpO2 and HR.

In term newborns, the SpO2 increases progressively, being higher in the first 10 minutes in those born vaginally. In newborns delivered vaginally, a higher HR was also observed in the first and last minutes evaluated.