The Experimental Study Of Establishing A Rabbit Model Of PR-MODS After Cardiac Arrest And The Intervention Therapy By Shengmai Injection

Post resuscitation multiple organ dysfunction syndrome (PR-MODS) is the most common complication after the resuscitation of the cardiac arrest, also is the important reason causing the failed resuscitation ultimately and bad prognosis. The exact pathogenesis of PR-MODS is not very clear, especially lack of the correlated animal model of PR-MODS. Now the animal study of cardiopulmonary and cerebral resuscitation still stays at the primary resuscitation stage of cardiac arrest, the studies of pathogenesis and contal measure already become the hot and difficult spots. The main purpose of this study is establishing a rabbit model with sudden cardiac arrest and PR-MODS by the method of clamping trachea to asphyxia, investigating the feasibility,pathogenesis and the effect of early intervention therapy by Shengmai Injection.ⅠClinical epidemiology investigation on cardiac arrest PR-MODS patients in ICUThe results display that there are 51 cases having SIRS in total 56 successful cardiopulmonary resuscitation patients, and there are 42 cases (75%) developing into cardiac arrest PR-MODS by step, among these 27 cases(27/42,64.29%)died. The most involving organs in sequence are brain with 38 cases(90.48%) and heart with 35 cases(83.33%),this shows that SIRS happens usually in cardiac arrest PR-MODS patients in ICU, later the morbility of MODS and mortality are both at high levels.II Investigation of the relevant factors in cardiac arrest PR-MODSUsing international cardiopulmonary resuscitation Utstein style statistics datas analyze the relevant factors effecting the genesis and prognosis of cardiac arrest PR-MODS. The results display that the genesis of PR-MODS is close related with bystander resuscitation,defibrillation times(>3 times),adrenalin dosage(>5mg), fainting-manual CPR time(>5 min),fainting-advanced airway time(>5 min),fainting-resuscitation drugs time(>5 min) and ROSC time(>10 min),SIRS(3 items). And some factors have obviously effect on the prognosis of PR-MODS(P<0.05), such as long ROSC time(>10 min),more involving organs(≥4),high arterial blood lactate level (>2mmol/L) and higher APACHE II scores(>15). These indicate that some measures could degrade the morbility of PR-MODS and mortality, such as the importance of the CPR rescue time after cardiac arrest, improve the body tissue perfuse and hypoxia status as soon as possible, and positive post resuscitation supportive treatments.III Establishing a rabbit model with sudden cardiac arrest by the method of clamping the trachea to asphyxia and investigating the feasibility.We use clamp the trachea for 8 minutes to asphyxia inducing cardiac arrest, investigate the actual feasibility of establishing the model of cardiac arrest. The results show that the changes of blood pressure of the rabbit before and after the asphyxia and ECG at cardiac arrest are the same to clinical cardiac arrest, and ROSC rate is 86.67%. The model is convenient and effect in judging the cardiac arrest and ROSC, and it can relatively satisfy the need to collection of studying sample. The model is fairly stable, and repeatability of the test is good. So the animal model building of sudden cardiac arrest by the method of clamping the trachea to asphyxia is convenient and it has the feasibility.IV The effect of ROSC of rabbit model with sudden cardiac arrest by the method of clamping the trachea to asphyxia and the changes of hemodynamics in early resuscitation by Shengmai InjectionObserve the effect of ROSC of rabbit and hemodynamics in post resuscitation by early using of Shengmai Injection. The result shows the rabbit ROSC time of Shengmai Injection group is obviously shorter than the saline control group. The LVSP,+dp/dtmax and -dp/dtmax at correspondding time spot of post resuscit- ation in Shengmai Injection group are higher than the saline group. And LVEDP is lower than the control group. These indicate that Shengmai Injection is profitable to the ROSC of the cardiac arrest, and improve the left ventricular diastolic and systolic function after cardiac arrest, and have the effect on stabling the hemodynamics.V The introduction research to modeling of rabbit cardiac arrest and PR-MODS by the method of clamping the trachea to asphyxia and the influence of asphyxia time selection for the modelingThe asphyxia time selected are 7 and 8 minutes and divide the rabbits into two different group randomly, observe the SIRS reaction condition, detect the TNF-αlevel via ELISA and indices of major organ function using whole blood automatic biochemistry analyzer as well as the pathological alteration under light microscope of ROSC rabbits. The result displays that the SIRS reaction emerges 12 to 24 hours after ROSC, the incidence rate of which is 100%, accompanied with significant elevation of serum TNF-αlevel as well as serum CK-MB,ALT,Cr,Glu level which reflecting major organ function, blood PaO2 decreases obviously 48 hours after ROSC. Pathological alteration of major organs mainly presented as infiltration of inflammatory cells and degeneration as well as necrosis in different degree of partial cells. The ROSC rate of the two groups is 100% and 86.67% respectively and has no significant difference(P<0.05),while the CPR time as well as the 6-hour mortality rate of the 7-minute asphyxia group are notablely lower than that of 8-minute asphyxia group(P〈0.05); according to the diagnostic criteria of MODS after cardiac arrest, the MODS incidence rate of the rabbits surviving over 12 hours after ROSC is 100%. Thus, the modeling of rabbit cardiac arrest and PR-MODS by the method of clamping the trachea to asphyxia is feasible, and the asphyxia time selected as 7 minutes possesses more practical application value.VI The influence of Shengmai Injection to the serum TNF-αlevel and indices of major organ function of rabbitsSelect the asphyxia time as 7 minutes and then grouping and modeling, and approach the influence of Shengmai Injection to the serum TNF-αlevel and indices of major organ function of rabbits. The result displays that the serum TNF-αlevel of rabbits belonging to Shengmai Injection group are obviously lower than that salt water injection group at different observation point after ROSC (P<0.05); the biochemical indicators including serum CK-MB,ALT as well as Cr level of the Shengmai Injection group 24 hours after ROSC are significantly lower than that of salt water injection group(P<0.05),the serum CK-MB,ALT level of Shengmai Injection group 48 hours after ROSC are also remarkably lower than that of salt water injection group(P<0.05),suggesting the evident inhibitory action of Shengmai Injection to serum TNF-αlevel after cardiac arrest. The damage condition of organs of Shengmai Injection group 24 to 48 hours after ROSC is lighter than that of salt water injection group, and the Shengmai Injection probably possesses better protection effects to heart and liver function.VII The influence of the early therapeutic intervention of Shengmai Injection to the cardiomyocyte ultrastructure of cardiac arrest and PR-MODS rabbits by the method of clamping the trachea to asphyxiaSelect the asphyxia time as 7 minutes and then grouping and modeling, and observe the influence of Shengmai Injection to the pathological alteration of cardiomyocyte ultrastructure of cardiac arrest and PR-MODS rabbits using light microscope and electron microscope. The result displays that cardiomyocyte of salt water injection group presents focal necrosis, the nucleus of necrosis cells vanish or display as karyopycnosis, the cytoplasm of which is cardinal red and the infiltration of a large number of inflammatory cells is observed; while the rabbit cardiomyocyte of Shengmai Injection group presents small focal necrosis, the acidophilia staining is strengthened, while the necrosis degree is lighter than that of salt water injection group, and the infiltration of a large number of inflammatory cells is not observed. The vacuolization of mitochondria of salt water injection group is obvious under electron microscope, the mitochondria arrangement is confused and pyknosis and aggregation is observed, the myofilament of partial cardiomyocyte collapse and is inordinate, the lipid droplet increases markedly. While the cardiomyocyte swelling of Shengmai Injection group is lighter, the myofilament arrangement is a little confused, partial cardiomyocyte exist fragmentation and is inordinate, but the light band and dark band of the sarcomere is distinct. The mitochondria is a little swollen yet the arrangement of which is orderly. The lipid droplet can be observed in some cardiomyocytes while is not as obvious as that of salt water injection group, and the vacuolization of mitochondria is extremely rare. Thus, the Shengmai Injection could prevent necrosis of cardiomyocyte through resisting ischemical reperfusion injury, so the inflammatory reaction is slight, and it can prevent irreversible damage to cardiomyocyte ultrastructure withmyocardial protection.VIII The influence of Shengmai Injection to cardiomyocyte apoptosis and the protein expression of Fas gene of cardiac arrest and PR-MODS rabbits by the method of clamping the trachea to asphyxiaSelect the asphyxia time as 7 minutes and then grouping and modeling, detect cardiomyocyte apoptosis using terminal deoxynucleotidyl transferase biotin-dUTP nick end labeling(TUNEL)method as well as protein expression of Fas gene and influence of Shengmai Injection using immunohistochemical method. The result displays obvious cardiomyocyte apoptosis and elevation of protein expression of Fas gene in cardiac arrest and PR-MODS rabbits, while the apoptotic index(AI)and Fas protein expression of Shengmai Injection group are significantly lower than that of salt water injection group(P<0.05),suggesting the existence of cardiomyocyte apoptosis in the process of cardiac arrest and PR-MODS, which related to the elevation of Fas protein expression. The Shengmai Injection may decrease cardiomyocyte apoptosis via suppressing the elevation of apoptosis protein expression thereby posses myocardial preservation function, and it may delay and block the occurrence of PR-MODS.On the whole, our study establishes cardiac arrest and PR-MODS animal model by the method of clamping the trachea to asphyxia firstly, and investigates the feasibility of the PR-MODS modeling,the generation mechanism as well as the influence of early therapeutic intervention of Shengmai Injection to PR-MODS from aspects of mediators of inflammation,functional biochemistry and pathological alteration of organs,cardiomyocyte apoptosis and expression of related gene, and establish valuable animal model for the following prevention and cure study of PR-MODS in cardiopulmonary resuscitation domain, meanwhile, to a certain degree, we also provide valuable and clinical practical theoretical foundation to the prevention and cure of PR-MODS using Chinese traditional medicine. The conclusion are as follows:①Among the cardiac arrest and restoration of spontaneous circulation patients taken in to ICU, the incidence rate of PR-MODS and the mortality rate are high, the prognosis closely relate with the time of restoration of spontaneous circulation as well as other factors, the key point is the recuperation of tissue perfusion and oxygen supply as soon as possible, and provide supportive treatment to organs after resuscitation.②On the basis of establishment of rabbit animal model by the method of clamping the trachea to asphyxia, the SIRS reaction after ROSC,the elevation of serum TNF-αlevel,the change of indices of major organ function as well as the pathological alternation of ultrastructure are observed, which reveals the feasibility of modeling of rabbit cardiac arrest and PR-MODS by the method of clamping the trachea to asphyxia, and the asphyxia time can be selected as 7 minutes in subsequent research.③The Shengmai Injection is in favour of the shorten of restoration of spontaneous circulation time as well as the stabilization of hemodynamics after resuscitation, thus provide clinical foundation for rescuing cardiac arrest patients using Chinese traditional medicine;④The Shengmai Injection can suppress the elevation of serum TNF-αlevel , alleviate the damage degree of major organs and decrease the expression of Fas protein thus posses myocardial preservation function,which provide theoretical foundation for clinical integrated control of PR-MODS;⑤The Shengmai Injection can improve the pathological alternation ultrastructurally of cardiomyocyte, possess myocardial preservation function to a certain degree, while it does not decrease the incidence and mortality rate of PR-MODS, which may related with the small sample of the study as well as multiple influence factors to the prognosis of PR-MODS.