Study design. During the preparation period, animals received 25 mL/kg 0.9% NaCl to prevent hypovolemia. When preparation was completed, a 30-minute period served to stabilize the measured variables. Measurements were taken over a 5-h period. Throughout the duration of the experiment, heart rate (HR), blood pressure (BP), pulmonary blood pressure (PBP), pulmonary capillary wedge pressure (PCWP), mixed venous oxygen saturation (SvO2), cardiac index (CI) and laser Doppler flowmetry measurements were recorded. Arterial and venous blood gas (A-VBG) was collected at the same time (except T and T30) until the study was completed. Animals were infused with 5 μg/kg/min of Escherichia coli lipopolysaccharide (LPS) from T0 to T30. We studied three groups of five animals receiving 5 mL/kg/h of different fluids: 0.9% NaCl (NC group), hypertonic sodium bicarbonate 8.4% (HSB group) and hypertonic sodium lactate 11.2% (HSL group). If mean arterial pressure (MAP) felt below 50 mmHg, a 2,5 mL/kg infusion of NaCl 0.9% was given as rescue therapy every 15 minutes. Bolus infusions were performed to maintain mean arterial pressure (MAP) above 50 mmHg.