Comparison of ventral coccygeal arterial and jugular venous blood samples for pH, pCO2, HCO3, Be(ecf) and ctCO2 values in calves with pulmonary diseases

The aim of this study was to determine whether venous blood samples can be used as an alternative to arterial samples in calves with respiratory problems and healthy calves. Jugular vein and ventral coccygeal artery were used to compare blood gas values. Sampling of the jugular vein followed soon after sampling of the ventral coccygeal artery in healthy calves (group I) and calves with respiratory problems (group II). Mean values of arterial blood for pH, pCO2, HCO3act in healthy calves were 7.475 +/- 0.004, 4.84 +/- 0.2 kPa, 28.45 +/- 1.30 mmol/L compared with venous samples, 7.442 +/- 0.006, 6 +/- 0.3 kPa, 30.93 +/- 1.36 mmol/L, respectively. In group II, these parameters were 7.414 +/- 0.01, 5.93 +/- 0.3, 27.73 +/- 1.96 mmol/L for arterial blood and 7.398 +/- 0.008, 6.85 +/- 0.2 kPa, 29.77 +/- 1.91 mmol/L for venous blood, respectively. There were no statistically significant differences between arterial and venous pH, HCO3act, Be(ecf), ctCO2 values with the exception of pCO2 (P = 0.001) in group II. In group I, correlation (r2) between arterial and venous blood pH, pCO2, HCO3act were 84.5%, 87.5%, 95.7%, respectively compared with the same parameters in group II, 80.8%, 77.1%, 70.3%. In conclusion, venous blood gas values can predict arterial blood gas values of pH, pCO2 and HCO3ecf, Be(ecf) and ctCO2- for healthy calves but only pH values in calves with acute respiratory problems (r2 value>80%).