Effect Of Goal-directed Fluid Management Based On Pleth Variability Index

OBJECTIVES:Blood lactate levels were used to investigate the role of pleth variability index (PVI) in guiding fluid infusion in patients undergoing major abdominal surgery under combined epidural and general anesthesia.METHODS:Thirty ASA Ⅰ～Ⅱ patients scheduled for major abdominal surgery under combined epidural and general anesthesia were randomized into 2 groups to compare intraoperative PVI-directed fluid management(PVI group) versus standard care (control group). A thoracic epidural catheter was inserted under local anesthesia. After a test dose of 4 mL of 1% lidocaine through the epidural catheter, general endotracheal anesthesia was initiated. A 500mL crystalloid fluid was given during induction. After induction,0.375% ropivacaine 5mL was given twice through the epidural catheter. Patients in PVI group were maintained with crystalloid fluid at 2 mL/kg/h; if the PVI was over 13%, a 250 mL colloid or crystalloid were rapidly infused. Vasoactive drug was given to maintain the mean arterial blood pressure above 65 mmHg. Patients in control group received a crystalloid infusion at 4-8 mL/kg/h, and quick fluid infusion was initiated if mean arterial blood pressure is less than 65 mmHg. Perioperative lactate levels, hemodynamic changes were recorded individually.RESULTS:The total amount of fluids and crystalloid amount infused in PVI group [1918(1640-2196) mL; 1356(1112-1599) mL] were significantly lower than the control group [2327(2047-2606) mL; 1715(1470-1961) mL], P< 0.05. Lactate levels on the first hour time-plot of the surgery and the maximum level during surgery were significantly lower in the PVI group(0.818 mmol/L,95% CI 0.601-1.034 mmol/L; 0.925 mmol/L,95% CI 0.709-1.141 mmol/L) versus control group(1.135 mmol/L,95% CI 0.913-1.357 mmol/L; 1.216 mmol/L,95% CI 1.010-1.422 mmol/L),P<0.05.CONCLUSIONS:PVI-based goal-directed fluid management in major abdominal surgery patients under combined epidural and general anesthesia can reduce the amount of fluids administration and blood lactate levels during surgery.