The Monitoring Value Of Pcv-aCO₂on Estimating The Prognosis Of CABG

Objective:More and more medical units began to practise coronary artery bypass grafting (CABG) with the development of cardiac surgery. But because of the big risk, more complications and poor prognosis of CABG surgery, that made the extensive development and application of coronary heart disease surgery was limited largely in domestic. It is especially important to reduce the incidence of complications and improve the prognosis effectively by finding and analyzing pathophysiological monitoring indicators. Traditional oxygen dynamic monitoring indexes all have a few limitations, so people began to pay close attention to Pcv-aCO2. Studies had shown that Pcv-aCO2is closely related to the ScvO2, and has better correlation with cardiac output than ScvO2-The researches about the influences of Pcv-aCO2on the judgment and prognosis of CABG postoperative condition has not yet been reported. This study statistically analyzed Pcv-aCO2and preoperative clinical, biochemical indexes and complications, with the expectation that finding some objective indexes which can accurately evaluate CABG postoperative apostasies and prognosis.Methods:Selects Patients with CABG82cases that hospitalized between2012.8to2013.1. Postoperative Ecg monitoring should be took after returned to ICU.(1) Collecting arteries and veins blood samples for blood gas analysis to measure Pcv-aCO2, ScvO2, PaO2, SaO2and Lac respectively at Oh,12h,24h after CABG.(2) According to the preoperative cardiac function, the presence of postoperative respiratory and circulatory complications in care unit, and ICU APACHEII scores, we divided cases into groups. Investigating the influences of preoperative cardiac function, ICU APACHEII scores and postoperative complications respectively on postoperative oxygen supply and demand balance.(3) The specificity and sensitivity of the Pcv-aCO2and ScvO2on estimating postoperative complications were investigated to find the better index.(4) Calculating the average of Pcv-aCO2and ScvO2respectively, different groups were made according to the average value. Investigating the effect of Pcv-aCO2and ScvO2on judging the specificity and sensitivity of postoperative complications by calculating the incidence of postoperative complications of each group, and comparing the differences of complication rate.Results:2.1The correlation between Pcv-aCO2and ScvO2, PaO2, SaO2, Lac. The results demonstrated a negative correlation between Pcv-aCO2and ScvO2; Pcv-aCO2had no obvious correlation with PaO2, SaO2and Lac.2.2By comparing Pcv-aCO2and ScvO2, SaO2, PaO2and Lac of group APACHEⅡ≤12and APACHEⅡ>12, it showed that:the Pcv-aCO2and ScvO2, SaO2, PaO2and Lac of two groups had no statistical significance.2.3For low cardiac function group and work normal group, the Pcv-aCO2and ScvO2, SaO2, PaO2and Lac of two groups had no statistical significance.2.4The value of Pcv-aCO2of with postoperative complications group was obviously increased than that of without postoperative group, while ScvO2decreased.2.5The analysis of Sensitivity and specificity showed that it was significant for using Pcv-aCO2and ScvO2to judge the presence of postoperative respiratory and circulatory complications. But Pcv-aCO2was more sensitive and specific than ScvO2.2.6The comparison of the incidence of postoperative complications of different Pcv-aCO2and ScvO2groups had shown:the postoperative complications incidence of Group A2and A3were higher than that of Group Al, while that of Group B3was higher than that of Group B1; The difference of group A1and B1was significant.Conclusion:The results demonstrated a negative correlation between Pcv-aCO2and ScvO2; The postoperative complications can affect Pcv-aCO2and ScvO2obviously. Pcv-aCO2and ScvO2can correctly reflect the state of tissue oxygen supply and demand, as well as the degree of tissue damage. The Pcv-aCO2can more accurate and sensitive than ScvO2on predicting complications. The complication rates of group ScvO2value>70%was much high than that of group Pcv-aCO2<8mmHg. When ScvO2value>70%, the condition Pcv-aCO2<8mmHg should be satisfied in order to achieve better tissue oxygen supply and demand balance, so as to reduce the incidence of complications and improve prognosis.