Arterial blood gas anomaly in canine hepatobiliary disease

Abstract

Arterial blood gas analysis is an important diagnostic and monitoring tool for respiratory abnormalities. In human medicine, lung complications often occur as a result of liver disease. Although pulmonary complications of liver disease have not been reported in dogs, we have frequently encountered hypoxemia in dogs with liver disorders, especially extrahepatic biliary obstruction. In addition, respiratory disorders account for 20% of perioperative fatalities in dogs. Therefore, in this study, we evaluated the respiratory status in dogs with hepatobiliary disease by arterial blood gas analysis. PaO2 and PaCO2 were measured. Alveolar-arterial oxygen difference (AaDO2), the indicator of gas exchange efficiency, was calculated. Compared to healthy dogs (control group), hepatobiliary disease dogs had significantly lower PaO2 and higher AaDO2. Hypoxemia (PaO2 of ≤80 mmHg) was observed in 28/71 dogs with hepatobiliary disease. AaDO2 was higher (≥30 mmHg) than the control group range (11.6 to 26.4 mmHg) in 32/71 hepatobiliary disease dogs. By classifying type of hepatobiliary disease, dogs with extrahepatic biliary obstruction and chronic hepatitis showed significantly lower PaO2 and higher AaDO2 than in a control group. Dogs with chronic hepatitis also had significantly lower PaCO2. The present study shows that dogs with hepatobiliary disease have respiratory abnormalities more than healthy dogs. Preanesthetic or routine arterial blood gas analysis is likely beneficial to detect the respiratory abnormalities in dogs with hepatobiliary disease, especially extrahepatic biliary obstruction and chronic hepatitis.

ACVIM consensus statement on the diagnosis and treatment of chronic hepatitis in dogs

“…Additional complications reported in humans with CH include hepatopulmonary syndrome, hepatorenal syndrome, spontaneous bacterial peritonitis, and hypersplenism. Although a clinical scenario resembling hepatopulmonary syndrome recently has been described in dogs with CH, the other complications have not been reported in dogs …”

A case report of suspected hepatopulmonary syndrome secondary to ductal plate malformation with chronic active hepatitis in a dog

“…We have previously encountered poor respiratory conditions in patients with hepatic disease. In particular, dogs with chronic hepatitis showed significantly lower PaO 2 and higher AaDO 2 than dogs in the control group [ 9 ]. The present case did not show serious respiratory signs; however, the respiratory rate increased slightly.…”