Resuscitation Using Intra-aortic Arch Blood Transfusion Increases Coronary Perfusion Pressure And Ameliorates Myocardial Dysfunction After Exsanguination Cardiac Arrest:A Rabbit Model

Background and objective:We sought to establish a rabbit model of exsanguination cardiac arrest(ECA),and compare the effects of rapid blood transfusion through the aortic arch or central vein on coronary perfusion pressure(CPP)during resuscitation,and determine whether resuscitation using intra-aortic arch blood transfusion can reduce the severity of post-resuscitation myocardial dysfunction and confer cardioprotection.Methods:(1).Forty-five New Zealand rabbits were divided into three treatment groups:chest compressions with intra-aortic arch blood transfusion(AAT)(n=15),chest compressions with intra-central vein blood transfusion(CVT)(n=15),and simplex intra-aortic arch transfusion without chest compressions(SAAT)(n=15).ECA was induced by rapid exsanguination from the left femoral artery and vein.After 15 minutes without intervention,resuscitation was initiated using rapid blood transfusion into the aortic arch through the left femoral artery,with or without chest compressions,or into the inferior vena cava through the left femoral vein,with chest compressions.Animals were observed for 6 h after return of spontaneous circulation(ROSC),during which haemodynamic parameters were recorded.CPP and the 6 hour survival rate in every group were recorded and analyzed.(2).Forty-five New Zealand rabbits were divided into three treatment groups:AAT(n=15),CVT(n=15),and SAAT(n=15).ECA was induced by rapid exsanguination from the left femoral artery and vein.After 15 minutes without intervention,resuscitation was initiated using rapid blood transfusion into the aortic arch,with or without chest compressions,or into the inferior vena cava with chest compressions.Animals were observed for 2h after ROSC.Then the blood specimens and myocardial tissue samples were collected.The serum levels of high-sensitivity cardiac troponin I(hscTnl)and brain natriuretic peptide(BNP),and the expression levels of hypoxia-inducible factor-1?(HIF-1?)in the myocardium were analyzed.Results:(1).Mean blood loss was 79.18±11.79mL.The CPP was significantly higher in the AAT and SAAT groups than in the CVT group during blood transfusion(at the 1st minute,AAT 61.24±33.00mmHg,CVT 23.72±16.54mmHg,SAAT 50.32±21.45mmHg,P<0.001;at the 2nd minute,AAT 75.97±33.72mmHg,CVT 27.25±21.10mmHg,SAAT 60.93±25.07mmHg,_P<0.001;at the 3rd minute,AAT 73.17±32.74mmHg,CVT 30.22±19.12mmHg,SAAT 65.65±25.26mmHg,P<0.001)and after ROSC(at the 10th minute,AAT 92.75±25.64mmHg,CVT 62.36±13.14mmHg,SAAT 81.94±16.16mmHg,P=0.004;at the 20th minute,AAT 90.53±26.09mmHg,CVT 62.94±11.75mmHg,SAAT 84.82±8.92mmHg,P=0.003;at the 30th minute,AAT 86.47±20.84mmHg,CVT 61.06±15.22mmHg,SAAT 84.69±10.57mmHg,P=0.001).Median survival time in groups were:AAT 5.0±0.41h,CVT 3.0±0.78h and SAAT 4.0±0.34h,there were significantly different among the three groups(P=0.027).(2).Mean blood loss was 80.04± 11.12mL,45 ECA rabbits model were successfully constructed.At 2h after ROSC,the serum levels of hscTnI and BNP were significantly lower in the AAT group than in the CVT and SAAT groups(hscTnI:AAT 10.10±3.32ng/L,CVT 13.08±2.43ng/L,SAAT 15.15±2.04ng/L,P<0.001;BNP:AAT 49.90±7.06pg/mL,CVT 63.50±11.59pg/mL,SAAT 68.05±12.62pg/mL,P<0.001).The light microscopy showed the pathological changes of cardiac myocytes.In the AAT group,the myocardial cells were stained clearly and the structure appeared complete.The cardiac myocytes were short,columnar,and arranged neatly.No coagulation necrosis was seen.In the CVT group,the structure of cardiac myocytes was not clear.The myocardial fibres adopted a wavy shape.Swelling of the cardiac myocytes was obvious.The myocardial gap appeared widened.A small number of vacuoles were found in the cytoplasm of the cells.In the SAAT group,the cytoplasmic staining of cells was uneven,and more vacuoles were visible.The cardiac myocytes appeared swollen,the cell boundary was unclear,and the arrangement appeared disordered.The cardiac muscle fibres adopted a wavy shape.Coagulation necrosis and lack of nucleus were noted in many cardiac myocytes.The expression of HIF-1? in the myocardium was confirmed based on the brown-yellow staining of the cytoplasm of cardiac myocytes.According to the specific method of grading immunohistochemical findings employed in this study,the expression of HIF-la was the lowest in the AAT group,and there was no significant difference between the SAAT and CVT groups.Conclusions:Intra-aortic arch blood transfusion increases the CPP during resuscitation and after ROSC,ameliorates myocardial dysfunction,and confers cardioprotection.We have also proposed a new method of ECA recovery:blood transfusions through catheter which was inserted into the aortic arch through the left femoral artery without chest compression?Our findings can be used to develop novel strategies for ECA resuscitation.