The Value Of Pcv-aCO₂ In Thoracoscopic Operation

Objective: To investigate the arteriovenous PCO2 difference(Pcv-aCO2) application value after thoracoscope heart operation.Methods: 100 patients underwent open-heart surgery under cardiopulmonary bypass were studied, who were hospitalized in cardiac department of Jining medical university during January 2013 to October 2014. There were 62 males and 48 females, whose age 21 to 63 old.The average age was 36 and the average weight was 51 kg. Atrial septal defect(ASD) was 39 cases,ventricular septal defect(VSD) was 34 cases, rheumatic mitral stenosis was 10 cases,mitral regurgitation was 12 cases,and stenosis was 5 cases. All patients were diagnosed by electrocardiogram,chest X-ray and echocardiography.The clinic index were compared between study group(thoracoscopic heart surgery, n=50) and control group(open-chest heart surgery, n=50). All patients received general anesthesia tracheal intubation and the operation was performed under hypothermia and cardiopulmonary bypass. The patients in study group were operated with thoracic surgery, and the middle right axillary midline incision was performed under 3 incisions. The patients in control group were in routine operation. During the operation of internal jugular vein or subclavian vein indwelling deep venous catheter. Pcv-aCO2 was calculated by blood gas calculation, and central venous oxygen saturation(ScvO2) was recorded.The ScvO2 and Pcv-aCO2 changes of 0h, 6h,12 h and 18 h were monitored after operation, and cardiac function of 0h,6h,12 h and 18 h were evaluated by echocardiography.Monitoring the preoperative,intraoperative,post-operative Pcv-aCO2 and Scv O2 correlation.Repeated measures analysis of variance was used to analyze Postoperative different time point index.Spearman correlation was used to analyze the degree and correlation of each index. P < 0.05 means significant difference.Results: 0h, 6h, 12 h, 18 h after thoracoscope heart operation,the patient’s Pcv-aCO2 decreased gradually,while the ScvO2 and EF increased gradually at the same time point(P < 0.05).There was significant difference between the time points(P< 0.05), Pcv-aCO2, ScvO2 and EF between the two groups have significant difference respectively(P < 0.05). Post-operative Pcv-aCO2 has negative correlation with ScvO2(r=-0.602). The control group and the abnormal indexes of heart function were not improved after operation.Conclusion: The detection of Pcv-aCO2 can reflect the situation of in vivo oxygen balance in patient’s body,it is better than the arterial blood gas analysis.Pcv-aCO2 and ScvO2 can provide data for clinical practice and early prediction of postoperative complications. Pcv-aCO2 has good correlation with cardiac function and ScvO2,it can be used to evaluate postoperative blood gas monitoring index and cardiac function.