Nitroglycerin and Epinephrine Improve Coronary Perfusion Pressure in a Porcine Model of Ventricular Fibrillation Arrest: A Pilot Study

Background: Cardiac arrest remains one of the leading causes of death worldwide. European Resuscitation Council Guidelines for Resuscitation 2005 recommend epinephrine for its treatment. Objectives: To estimate whether the administration of a vasodilatator such as nitroglycerin in combination with epinephrine during cardiopulmonary resuscitation would improve resuscitation outcome in an established model of ventricular fibrillation. Methods: Design: Prospective, randomized, blinded, controlled study. Setting: Animal research laboratory. Ventricular fibrillation was induced in 20 Landrace/Large-White pigs. It remained untreated for 8 min before attempting resuscitation precordial compressions, mechanical ventilation, and electrical defibrillation. Animals were randomized into two groups, 10 animals each. Group A received saline as placebo (10 mL dilution, bolus) and epinephrine (0.02 mg/kg). Group B received nitroglycerin (50 μg/kg) and epinephrine (0.02 mg/kg) during cardiopulmonary resuscitation. Electrical defibrillation was attempted after 10 min of ventricular fibrillation. Results: Four animals in group A restored spontaneous circulation in comparison to eight in Group B. Coronary perfusion pressure (p < 0.0001) was significantly increased in Group B during cardiopulmonary resuscitation. Conclusion: A vasodilatator, when administered in combination with a vasopressor such as epinephrine during cardiopulmonary resuscitation, increases coronary perfusion pressure.