Effect of dopamine on hemodynamics and cerebral oxygen metabolism in the early stage of post-resuscitation in rabbit with cardiac arrest / 中华急诊医学杂志

ABSTRACT

Objective To observe the effects of dopamine in different doses on hemodynamics and cerebral oxygen metabolism in the early stage of post-resuscitation in rabbit with cardiac arrest.Methods Healthy adult rabbits were randomly(random number) divided into 4 groups according to the different doses of dopamine administrationcontrol group (CG),low dose group (LG),medium dose group (MG),high dose group (HG),(n=15 in each group).Ventricular fibrillation (VF) was induced by electricity and cardiopulmonary resuscitation (CPR) was performed subsequently as the experiment designed.When 10 rabbits with restoration of spontaneous circulation (ROSC) were got each group,it was enough for experiment carried out.Cardiac output (CO),mean arterial pressure (MAP),heart rate (HR),systemic vascular resistance index (SVRI) and the cerebral local tissue blood oxygen saturation (TOI) were observed at 0 min,15 min,30 min,60 min,120 min after ROSC.The animals were sacrificed at 120 min after ROSC,brain tissues were harvested for study by using HE staining.Repeated measure analysis of variance was used to determine the statistical significance among the four groups at different intervals.Multi-group quantitative data was analyzed by one way ANOVA and then further by LSD test for multiple comparisons.Chi-square test or Fisher's exact probabilities was applied for multi-group binomial classification variable.Log-rank test was used for comparisons of survival curves in four groups.A twotailed value of P＜0.05 was considered statistically significant.Results There were no differences in the rate of ROSC among groups.Compared with CG and LG,ROSC time was shorter in MG (277±15 vs.190±12,P＜0.01;252±16 vs.190±12,P=0.016) with higher 120 min survival rate (20％ vs.90％,x2=9.899,P=0.005;30％ vs.90％,x2=7.5,P=0.02).CO was higher in MG than that in other groups at all given intervals in the early stage of post-resuscitation(P＜0.05).MAP levels were significantly higher in MG and HG compared with CG and LG at given intervals 15 min after ROSC (P＜0.05).SVRI was significantly higher in HG than that in other groups at all given intervals after ROSC (P＜0.05).Compared with other groups,the TOI levels in MG were significantly higher than that in other groups at 15 min and 30 min after ROSC (P＜0.05).The median survival time in MG and HG was significantly longer than that in CG and LG.The number of cellular necrosis in MG (28.4±1.0) was significantly fewer than that in other groups (CG 41.2±1.5;LG 41.0±2.0;HG 39.6±1.9) (P＜0.01).Conclusion The moderate dose of dopamine might maintain MAP and CO at a higher level meeting the cerebral oxygen metabolism in the early stage of post-resuscitation from cardiac arrest in rabbits.