The Effect Of P（cv-a）CO₂Guided Fluid Therapy To The Patient Undergoing Open Gastrointestinal Surgery

Reduced liquid intake and/or increased fluid losses are frequently observed in patients undergoing abdominal gastrointestinal operation due to various preoperative preparations. In addition, vasodilatation induced by anesthetics even worsens the effective circulating volume and tissue perfusion. It’s very important that a suitable fluid therapy should be implemented during anesthesia. However, traditional methods can not reflect the infusion of patients and the situation of the tissue perfusion. The urine volume, blood lactic acid and other indicators to guide transfusion has a certain lag, is not conducive to the normalization of hemodynamics in early recovery. Central venous oxygen saturation (ScvO2) has become a goal directed therapy of liquid recovery in septic patients and so on critically ill patients and other surgical patients, and venous-arterial PCO2(P(cv-a)CO2) is an important supplement of the ScvO2index. However, by now no studies that have confirmed the effect of P(cv-a)CO2as the only indicator in guiding fluid therapy. Therefore, this study is to evaluate the outcome and tissue perfusion of the patients who undergoing gastrointestinal operation and fluid therapy guided by P(cv-a)CO2control to those guided by ScvO2.Methods:From June2012to April2013, forty patients, ASA grade Ⅰ～Ⅱ, undergoing open gastrointestinal surgery were randomly divided into2groups (n=20each):ScvO2guided fluid therapy (group S) and P(cv-a)CO2guided fluid therapy (group P). All patients were fasted12h, no water4h preoperative, and infused10ml/kg lactated Ringer’s (LR) solution before anesthesia induction, they were all also given a continuous lactated Ringer’s (LR) solution’s infusion at the speed of2ml.kg-1·h-1during the operation. Meanwhile, patients would receive6%HES130/0.4(free flex6%HES130/0.4, Fresenius Kabi) infusion ScvO2<75%(group S) or P(cv-a)CO2≥6mm Hg (group P). Arterial and central venous blood gas analyses were performed every20minutes after skin incision, with venous and arterial lactate value measured at the same time. Also, the anal exhaust time after surgery, postoperative complications and28-day mortality were recorded.Results:Compared to group S, the arterial lactate value in T4(after operation began80min) and venous lactate value in T5(after operation began100min) were significantly decreased in group P (P=0.013and P=0.044, respectively), while other lactate values were not different (P>0.05). The volume of fluid infusion were (1344±244)ml and (1105±266)ml in group P and group S, which was statistically different (P=0.005). The anal exhaust time was not different between the two groups (P=0.673),although it appeared to be earlier in group P. All the patients were survival, and there were no obvious postoperative complications.Conclusion:Compared to group S, there was a obvious improvement in tissue perfusion in group P, while no differences in the recovery of gastrointestinal function and outcome were found between the two groups.