The relationship of arterial blood pH and pCO2 to the viability of the newborn piglet.

Clinical observations were made on the majority of 749 newborn piglets from 75 litters and the blood pH and pCO(2) levels in samples taken from an umbilical artery were determined in 299 of these piglets. A method of individual clinical assessment was developed which reduced the effect of subjective error on the evaluation of viability at the time of delivery. Blood samples were collected from the umbilical artery prior to the onset of respiratory movements and it was found that increased acidemia and hypercapnia were associated with reduced viability. The pH values in severely depressed piglets were between 6.50 and 6.95 and pCO(2) values between 105 and 185 mm Hg, whereas in the fully viable animals, the ranges were 7.10-7.42 and 46-75 mm Hg respectively. It was concluded that a large proportion of the mortality and reduced viability at the time of delivery could be attributed to intra-uterine asphyxia.