The Protective Effects Of Different Myocardial Protection Method On Fetal Goat Myocardial Function

Objective: To assess the protective effects of the STH solution,HTK solution and beating heart of cardiopulmonary bypass?CPB?on fetal goats myocardium function.Methods: 18 pregnant goats,25.72±4.29 kg weight,were pregnant with 18 fetal goats.Divided into three groups: group is not stopped?not stopped group?,STH group?st.Thomas protection fluid group?,HTK group?HTK solution group?.Three groups of animals are made sternum midline incision,after completely heparinization,establish CPB were the main pulmonary artery-turn right atrium intubation flow,extracorporeal circulation loop established began circulation.Among st.Thomas protection group and HTK protection group in extracorporeal circulation began with aortic clamp clip aortic perfusion liquid myocardial protection,unstopped group not perfusion fluid of myocardial protection.Control fetal goats extracorporeal circulation flow rate in more than200 ml/kg/min and water tank 40?temperature.St.Thomas protection group and HTK protection group to fetal goat cardiac arrested 30 minutes,and then open the ascending aorta and lets fetal goat cardiac restore to beat,leave the extracorporeal circulation after 30 minutes,to observe for 2 hours,not stopped group to turn 60 min after stopping flow observation 2 hours.Before CPB?turn30 min?turn 60 min after downtime1 h and 2 h taking neck venous blood 5 ml,axillary artery blood 1 ml.Fetal goat on the venous blood take supernatant,repackaging into EP tube,add-80 ? refrigerator frozen storage.2 h after downtime,shearing fetal goat right atrial myocardial tissue size about 1 * 1 * 1cm,placement test tube containing 4% formalin liquid seal save interesting,after waiting for 1 week for dehydration,paraffin embedding,animal testing is completed with unified TUNEL staining to observe apoptosis,shearing ventricular muscle several blocks used in the detection of lactic acid and ATP.All time points,respectively,measuring the heart rate,mean arterial pressure,extracorporeal circulation flow rate,PH value,Pa O₂,Pa CO₂,residual alkali,K⁺,Na⁺,Ca²⁺,glucose,lactic acid,hemoglobin,at all time points collected fetal goats venous blood myocardial damage index of inspection: calcium protein troponin I and CKMB,calcium protein troponin T.This study collected all the data are processed with SPSS21.0 statistical software,measurement data with mean±standard deviation?x±s?method.Significant difference between the two groups inspection using the single factor variance?Student 's t-test?,multiple sets of significant comparison between the one-way ANOVA.Results:1.Three groups of fetal sheep at all time points of axillary artery in measured blood gas,p H,PO₂?mm Hg?,PCO₂?mm Hg?,K⁺?tendency/L?,Ca2 +?tendency/L?at various time points compared had no statistical difference?P >0.05?.Time after T3 and T3 HTK group Na +?the tendency for L?than STH group?P < 0.05?;In T3,HTK group of K +?mmo/L?,Lac?tendency/L?,BE?the tendency for L?concentration is lower than STH group?P < 0.05?;T4,HTK group of Hct?%?compared with STH,statistically significant?P < 0.05?.2.Extracorporeal circulation before fetal sheep serum concentration of c Tn T and c Tn I and CKMB respectively in the comparison between the three groups had no obvious difference?P = 0.430,P = 0.430,P = 0.071?.Serum c Tn I?ng/L?concentration change,when T1,T2,T3 is compared between three groups had no statistical difference?P > 0.05?;T4 c Tnl relatively before CPB STH group was obviously increased?P < 0.05?;T5 is not stopped and HTK group when both c Tnl their generation before CPB?P < 0.05?;T4 and T5 HTK group with STH there are statistically significant differences between groups?P < 0.05?;T4 STH and T5 when STH group,HTK group stopped and not statistically significant?P< 0.05?.3.HTK group and the number of TUNEL positive cells STH group were less stopped way increased significantly?p = 0.000 and p = 0.048?,but STH TUNEL positive cells was more HTK group increased significantly?p = 0.007?.4.STH group myocardial ATP content organization is not stopped and HTK lower?P < 0.05?;HTK lactic acid content and not stopped group have statistical difference?P < 0.05?;STH group of lactic acid content and not stopped and HTK group have statistical difference?P < 0.05?.conclusion Fetal sheep extracorporeal circulation,not stopped for myocardial protection was better than stopped.In fetal sheep stopped with STH cardiac arrest liquid ratio,HTK solution on myocardial metabolism,reduce myocardial injury markers has obvious advantages,the release of TUNEL labeled cells apoptosis,myocardial ATP enzyme levels have increased.HTK solution stopped for longer than with STH,can cause hyponatremia.