TDK conference 2024

Arterial blood gas analysis provides insight into the oxygenation and ventilation status of animals, which can be significantly influenced by various respiratory and cardiovascular diseases. Arterial blood gas parameters (paO2, paCO2, pH) allow us to assess the severity of the disease and the effectiveness of the treatment. The aim of our research was to enhance the diagnostic value of this method and to determine whether there is an arterial blood gas parameter that differs in dogs with respiratory or cardiovascular disease.

For this study, arterial blood was drawn from 25 dogs with respiratory and/or cardiovascular diseases, and their most important acid-base parameters (paO2, paCO2, pH, and lactate) were compared. Out of the 25 patients 16 had respiratory-, four had cardiovascular- and four patients had both diseases. The cases were collected from the dogs that came to the Diagnostic Imaging Unit of the Small Animal Clinic for a cardiology examination or a respiratory endoscopy. The arterial blood sampling was done without sedation or additional oxygen therapy in every case to detect the differences in each group. The blood was taken from the femoral or dorsal pedal artery and analyzed immediately after sampling with an EPOC® Critical Care/blood gas analyser (Woodley Equipment Company Ltd., UK) at the Intensive Care Unit of the Small Animal Clinic.

Out of the 25 patients, 11 (44%) were hypoxemic, 12 dogs (48%) showed an abnormal carbon dioxide level, and 19 patients (76%) had elevated alveolo-arterial (Aa)-gradient value. Based on the analysis of the three disease categories (respiratory disease, cardiovascular disease, both respiratory- and cardiovascular disease), it can be stated that the oxygen arterial partial pressure was significantly lower (p<0.05) than the normal value in the group of patients with respiratory disease. The Aa-gradient value was significantly elevated (p<0.05) in both the respiratory disease group and the group with both respiratory and cardiovascular disease. Comparing the three disease groups, no significant difference with clinical relevance was found in any of the arterial blood gas parameters.

In our study, we couldn’t find any arterial blood gas parameter that could differentiate respiratory from cardiovascular diseases. However, our results confirmed the usefulness of arterial blood gas analysis when evaluating the severity of the disease in a patient with respiratory or cardiovascular disease.