The Value of Central Venous-arterial Carbon Dioxide Difference

Compensatory dilatation was performed firstly and 5ml/kg crystal solution was added within 30min before induction of anesthesia.When SVV≥13%, infusion of colloidal solution 2ml/kg was performed 15-20 minutes.If the increase of SV was≥10% after the liquid impact and the SVV was still≥13%, the colloidal solution was used again for 2mL/kg and the infusion was maintained until the SVV \< 13%.The infusion was stopped when the SVV \< 10%.If the increase of SV was less than 10% or CI \< 2.0L/min/m2 after infusion, dobutamine was given intravenously to observe the change of SV. If the increase of SV was greater than 10%, dobutamine could be maintained and the above fluid regimen continued.If the increase of SV was less than 10% and MAP≥65mmHg, the infusion of liquid was stopped and replaced with 4ml/kg/h infusion for maintenance.If the increase of SV was less than 10% and MAP was less than 65mmHg, the infusion was suspended.