Influence of Fasting on Canine Arterial and Venous Blood Gas and Acid-Base Measurements

Arterial and venous blood gas profiles were obtained from 33 clinically normal adult dogs of two breeds (German Shepherd Dog and English Pointer) 4 and 24 hours after eating. Fresh drinking water was available. All dogs were fed a nutritionally complete and balanced dry diet. Blood gas parameters measured included pH, pCO₂, pO₂, bicarbonate, base excess, total carbon dioxide, oxygen content, and oxygen saturation.
Statistically significant differences (P < 0.01) were found between sampling intervals (4 and 24 hours postprandial) for pCO₂, bicarbonate, total carbon dioxide, and base excess, for arterial and venous blood samples.
Statistically significant differences (P < 0.01) were found between arterial and venous blood for all parameters, at both sampling intervals.
No statistically significant interactions (P > 0.05) were found between sample type (arterial or venous) and sampling interval.
Correlations between arterial and venous samples were generally (but not exclusively) higher than correlations between sampling intervals. Breed differences were also noted.