Low oxygen in veins after shock treatment in sick dogs

Abstract

OBJECTIVE: To evaluate traditional and global perfusion parameters in clinical canine shock patients, and to evaluate for occult hypoperfusion as evidenced by low central venous oxygen saturation or high plasma lactate concentrations in clinical patients resuscitated to traditional endpoints. DESIGN: Clinical observational trial designed with a 1-year data entry period and patient follow-up of 28 days posthospital presentation. SETTING: Large, private urban teaching hospital, and emergency and critical care center. ANIMALS: Adult canine patients presenting to the emergency department with untreated shock. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Patients received fluid resuscitation to normalize perfusion parameters based on physical examination and arterial blood pressure (BP). Monitoring of central venous pressure (CVP) and central venous oxygen saturation (ScvO2 ) was feasible with current standard of care interventions in critically ill, client-owned dogs. Decreased ScvO2 was observed in 37.8% of patients resuscitated to normal traditional perfusion parameters. Hyperlactatemia was commonly recorded. CONCLUSIONS: Decreased ScvO2 exists in a significant proportion of critically ill dogs following standard fluid resuscitation for shock, providing a relevant target population for implementation of a more standardized early goal-directed therapy bundle in veterinary patients. Normalization of heart rate, blood pressure, mentation, and perfusion parameters directed by physical examination may be attained despite the persistence of significant tissue hypoperfusion and oxygen debt.