[Comparison of arterial and venous blood gas and acid-base values in prematurely born healthy calves or calves with a late asphyxia].

The arterial and venous blood gas and acid-base values of 44 calves delivered by caesarean section before term were examined during the first seven days of life. The newborns were divided into two groups based on clinical observations during the first hour of life, the blood pH and the base deficit: Group 1: 30 calves without respiratory distress syndrome (vital, non-asphyxial); they did not develop any diseases in the course of the experiment. Group 2: 14 calves with respiratory distress syndrome (asphyxial); 9 of these animals died in the course of the experiment. The blood gas and acid-base parameters (blood pH, base deficit, pCO2, pO2) measured in venous blood of the calves without respiratory distress syndrome (group 1) were similar to those cited in the literature for calves delivered at term. Among the calves that had survived respiratory distress syndrome, significantly decreased blood pH and increased base deficit values were found in both venous and arterial blood even on the third day after birth. Differences in pCO2 and pO2 were, however, no longer statistically significant between the two groups after 24 hours of life. For blood pH, base deficit, and pCO2 significant correlations were consistently found between the values in venous blood and the corresponding values in arterial blood in vital (non-asphyxial) calves. Due to the considerably smaller number of animals significant correlations between these parameters were less frequent in asphyxial calves, although some of the correlation coefficients were higher than in the vital calves. Experimentally induced influences and animal variation made the corresponding pO2-values of venous and arterial blood in both test groups less unequivocal. The analysis of arterial blood gas and acid-base parameters was not more conclusive than the analysis of venous blood regarding diagnosis and prognosis of respiratory distress syndrome. The blood pH and base deficit seemed to be the most suitable parameters to evaluate the severeness of the disease.