[Acid-base profile evaluation in central and peripheral arterial and venous blood in cattle]

In veterinary medicine mainly venous blood is used for acid-base balance determinations. This blood, however, does not allow to evaluate the respiratory component, therefore arterial blood samples have to be taken and examined in cases requiring such measurements (respiratory tract diseases, assessment of the degree of compensation in disturbed acid-base conditions). For this reason, central and peripheral arterial blood samples from the a. axillaris and a. subclavia, and the a. auricularis, respectively, were taken from 14 head of cattle, and the values of selected acid-base parameters (pH, pCO2, pO2, HCO3, BE and SAT) were compared. Simultaneously, venous blood samples (v. jugularis) were also examined. Comparison of arterial and venous blood samples (Tab. I) revealed statistically significant differences in pH (p < 0.01) as well as in pCO2, pO2 and SAT values (p < 0.001). In HCO3 and BE, no significant differences were observed. Comparison of arterial blood samples in relation to sampling sites (peripheral and central) disclosed no significant differences in the single parameters; all values correlated at a high level (Tab. II, Figs. 1-6). The highest correlation levels were determined for BE (r = 0.984), HCO3 (r = 0.959), pH (r = 0.944) and pCO2 (r = 0.938) whereas those recorded for SAT (r = 0.877) and pO2 (r = 0.874) were lower. Arterial blood sampling from the a. auricularis caudalis seems to be simpler than sampling from the more central parts that are difficult to approach mainly in fat animals.(ABSTRACT TRUNCATED AT 250 WORDS)