Acid-base parameters and alveolar-arterial oxygen tension gradients in healthy neonatal and postneonatal infants.
In a randomly selected group of asymptomatic neonatal and postneonatal infants, acid-base parameters and oxygen tension measurements in arterial blood (radial artery) were carried out during air and oxygen breathing. Acid-base results showed a mild, partially compensated metabolic acidosis, indicating adequate pulmonary function. Arterial oxygen tension was in the normal range for this age group. Calculated alveolar oxygen tension levels demonstrated alveolar-arterial gradients of about 30 mm Hg during air breathing and 320 mm Hg during O2 breathing. Volumes of R-L shunts calculated from these gradients, were in the order of magnitude commonly found at this age, i.e., about 20% of right cardiac output. No differences were discernible between infants of appropriate weight for gestational age and small-for-date infants.
D000136:Acid-Base Equilibrium; D000138:Acidosis / Q000175:diagnosis; D001158:Arteries; D001724:Birth Weight; D002245:Carbon Dioxide / Q000097:blood; D006801:Humans; D007231:Infant, Newborn; D010100:Oxygen / Q000097:blood*; D010313:Partial Pressure; D011650:Pulmonary Alveoli / Q000378:metabolism
D002245:Carbon Dioxide; D010100:Oxygen