Tissue oxygen levels in dogs with natural shock and survival links

Abstract

OBJECTIVE: To measure tissue oxygen saturation (StO) in a population of dogs with naturally occurring shock and to evaluate the relationship of StOwith an established veterinary severity scoring system (Acute Patient Physiologic and Laboratory Evaluation) and patient survival. DESIGN: Prospective observational study. SETTING: University teaching hospital. ANIMALS: Twenty-five adult dogs presenting in shock, as determined by the presence of hypotension, the calculated shock index, and hyperlactatemia. INTERVENTIONS: StOwas measured prior to any therapeutic interventions. Blood samples were also collected for measurement of plasma lactate, complete blood count, and a serum biochemical profile. Abdominal and thoracic focused assessment with sonography was also performed. MEASUREMENTS AND MAIN RESULTS: Dogs enrolled in this study had lower mean (±SD) StOvalues (65.12 ± 17.7%) than previously reported in experimental models of canine hemorrhagic shock. There was a moderate correlation between lower StOand increasing Acute Patient Physiologic and Laboratory Evaluation scores. A single StOvalue, assessed prior to therapeutic intervention, was not a sensitive predictor of mortality in this population. CONCLUSIONS: Dogs with naturally occurring shock have lower mean StOvalues than those previously reported in dogs with experimentally induced shock. A lower initial StOwas associated with worse disease severity but was not a significant predictor of survival in this population.