Effects Of Short-acting β-adrenergic Blocker On Postresuscitation Myocardial Dysfunction And BNP After Cardiac Arrest In Rabbits

Objective: Postresuscitation myocardial dysfunction contributes to the high fatality rate following successful resuscitation. B-type natriuretic peptide (BNP) is the cytokine released from the ventricles of the heart in response to hemodynamic stress, and is known to assess the left ventricular dysfunction. The purpose of this animal research was to investigate the effects of short-acting β -adrenergic blocker on the changes of cardiac function and concentration of BNP in the plasma during the early stage after cardiopulmonary resuscitation(CPR) from sudden cardiac arrest(CA) attributable to ventricular fibrillation(VF ).Methods: Treated with epinephrine or epinephrine with esmolol pretreatment, Hemodynamic values and concentration of BNP were measured in eighteen anesthetized rabbits, twelve rabbits were performed CA from VF, and at different time points during the early stage of postresuscitation period (30-240 min).Results: The left cardiac function was significantly reduced and progressively declined in all rabbits during the early stage of postresuscitation period;the peak positive first derivative of left ventricular pressure (Peak + dp/dt) was significantly decreased to 57.1% of baseline at 30 min, 33.7 % of baseline at 120 min in only epinephrine group. And peak + dp/dt in the epinephrine with esmolol-pretreatment group was significantly different fromthe epinephrine-treatment group. The peak negative first derivative of left ventricular pressure (Peak-dp/dt) also differed significantly between the two study groups. The left ventricular end-diastolic pressure (LVEDP) showed a marked rise in the two treatment -groups at all time points, and there was significantly different between epinephrine-treated group and epinephrine with esmolol-pretreated group. In both treatment-groups, the BNP concentrations in plasma were detected higher than control group throughout the observation period. The increases in measured BNP concentrations could be observed at each postresuscitation time intervals, and the differences of the BNP concentrations weie significant between the two treatment-groups during the observation period.Conclusion : A short-acting P -adrenergic blocker administered immediately during resuscitation improved postresuscitation myocardial dysfunction, and reduced the concentration of BNP during the early postresuscitation period after CPR from CA.