ABSTRACT
Objective To evaluate the efficacy of pleth variability index (PVI) in guiding volume therapy in the patients undergoing thoracoscopic surgery.Methods Forty patients of both sexes, aged 18-64 yr, with body mass index＜35 kg/m2 , of American Society of Anesthesiologists physical status I or Ⅱ ,scheduled for elective thoracoscopic lobectomy, were randomized into 2 groups (n =20 each) : control group (group C) and PVI group.During induction of anesthesia, multiple electrolyte solution was infused rapidly as a bolus of 250 ml, followed by a 2-8 ml · kg-1 · h-1 infusion.In group C, 6％ hydroxyethyl starch 130/0.4 and sodium chloride injection 50 ml and metaraminol 0.5 mg were administered to maintain mean arterial pressure ≥ 65 mmHg.In group PVI, 6％ hydroxyethyl starch 130/0.4 and sodium chloride injection 50 ml and metaraminol 0.5 mg were administered to maintain PVI ≤ 13％ and mean arterial pressure ≥ 65 mmHg.Immediately after the beginning of one-lung ventilation (T1) , immediately after the termination of one-lung ventilation (T2) and at 1 h after surgery (T3) , arterial oxygen saturation were recorded, and arterial blood samples were collected for blood gas analysis, and for determination of lactic acid concentrations.The blood creatinine concentrations were measured at 24 h before and after surgery.The fulid balance was recorded.Results The amount of colloid solution infused, total volume of fluid infused and lactic acid concentrations at T3were significantly lower in group C than in group PVI.There were no significant differences in the amount of crystralloid solution infused, urine volume, blood loss, arterial oxygen saturation at each time point, and blood creatinine concentrations at 24 h before and after surgery between the two groups.Conclusion PVI-guided volume therapy can not only maintain adequate blood volume and tissue perfusion, but also reduce the amount of fluid infused, and is helpful in mitigating lung water overload when used for the patients undergoing thoracoscopic surgery.