Echocardiography-guided hemodynamic optimization in dogs with hypovolemic shock. A parallel multicenter randomized controlled trial.

Intravenous fluid resuscitation plays a critical role in achieving hemodynamic optimization in critically ill patients. Hypovolemia is a significant risk factor for multi-organ failure, while excessive fluid administration can result in harmful complications such as acute kidney injury and acute respiratory distress syndrome. Additionally, fluid overload has been linked to higher in-hospital mortality rates in dogs.5 Consequently, optimizing hemodynamic status is necessary for effective clinical management. While balanced crystalloid boluses are currently recommended for the hemodynamic management of patients in shock, the optimal fluid volume remains a subject of debate. The fluid infusion bolus typically ranges from 10 to 30 mL/kg in hypovolemic dogs and is repeat until clinical improvent. After administering a fluid bolus, it is crucial to assess various hemodynamic variables to determine if further fluid administration is needed. Additionally, venous blood lactate concentration and capillary refill time, has been shown to be useful tools to guide fluid therapy in human medicine. Echocardiography has emerged as a tool for assessing both volume status and fluid responsiveness in dogs with low inter- and intra-observer variability. However, its potential to individualized fluid therapy by determining the precise volume to be administered has yet to be explored. The objective of this study is to compare two strategies for administering balanced crystalloid solutions to dogs with hypovolemic shock: an echocardiography-guided (ECHO) strategy and a non-echocardiography-guided (CONTROL) strategy. We hypothesize that the echocardiography-guided approach will result in faster hemodynamic optimization and a greater reduction in venous blood lactate concentration compared to the non-echocardiography-guided approach.