The Clinical Study Of Effects Of Different Oxygen Tension On Decay-accelerating Factor In The Erythrocyte During CPB

Abstract:Objective:To investigate effects of different oxygen tension on Decay accelerating factor in the erythrocyte during CardiopulmonaryBypass.Methods:Forty patients were randomly divided into four groups:The hyperoxic group with cyanotic congenital heart disease(group A,n=10) and hypoxic group(group B,n=10);The hyperoxic group with acyanotic heart disease(group C,n = 10) and hypoxic group(group D,n = 10).Intravenous access and arteriovenous invasive puncture were done on four groups of patients in the operating room,in which endotracheal intubation with Anesthesia-inhalation after rapid induction.CPB was established after the median sternotomy.Oxygen tension in the hypoxic group was controlled on 100～250mmHg and 300～500 mmHg in hyperoxic group during CPB.Blood samples were obtained before CPB(T₁),and CPB 15min(T₂),aortic opening 15 min(T₃),and postoperative 24 hours(T₄) respectively in all groups,detecting arterial blood gas at the same time.The samples were placed in tubeâ… (0.2ml),â…¡(0.2ml),â…¢(3ml) respectively.The samples in the tubeâ…¢were centrifuged by 2500 r/min for 5min at room temperature,and plasma from the upper level of Centrifugalâ…¢.Plasma 0.3 mL and N S 0.2 mL were added to tubeâ… with yeast cells(5×10⁸/ml) 0.2ml and plasma 0.3 mL were added to tubeâ…¡.Monoclonal antibody of mouse anti-human CD55 FITC fluorescent were integrated into CD55 in the erythrocyte directly,and then it was incubated for 60 min at 37℃.Finally the expression of CD55 in the erythrocyte was detected by flow cytometry.Results:Firstly,for the patients' general conditions:There were without significant differences between group A and group B on the patients' ages,weights,CPB time,aortic cross-clamping time,and nasopharyngeal temperature.The same was true with group C and group D.Secondly,for arterial blood gas:there were no significant differences within each group T₂ and T₃ in the PaO₂,and HCT.The serum lactate level was gradually increased through CPB period and postoperative 24 hours,with significant differences within each group T₂,T₃,and T₄ as compared with T₁(P＜0.05 or P＜0 01).However,there were no significant differences between group A and group B.The same was true with group C and group D.Thirdly,for the quantity and activity of CD55 in the erythrocyte:After initiation of CPB the activity of CD55 in the erythrocyte began to increase gradually in the group A,and there were significant differences CPB 15min,and aortic opening 15rain as compared with before CPB(P＜0.05),and then decreased progressively postoperative 24 hours to that before CPB;The quantity of CD55 in the erythrocyte was without significant differences at each time point in the group A.There was no significant difference at each time point in the group B,group C,and group D in the quantity and activity of CD55;and no significant differences for group A as compared with group B;and group C as compared with group D. Conclusions:The activity of erythrocyte CD55 in cyanotic heart patients was markedly increased by high oxygen tension during CPB with anoxic erythrocyte is possible reoxygenation-injury;The immune function of erythrocyte will be protected by Controlling oxygen tension.