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

Abstract

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

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

Patients and Method: Prospective observational study in healthy term newborns, delivered vaginally or by cesarean section, with maternal bonding, carried out at sea level. A continuous postductal 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.

Results: 324 healthy term newborns that met the inclusion criteria were included, of which 160 born vaginally and 164 by cesarean section. The SpO2 increased progressively 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.

Conclusion: 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.