Protective Effects of Progesterone on Neurological outcomes in a Rat Model of Cardiac Arrest

Objective: A significant percent of survivors from cardiac arrest and resuscitation suffer permanent brain damage. Previous studies have demonstrated the Neuroprotective effects of progesterone on regional brain ischemia and injury. In the present study, we investigate the Neuroprotective effects of progesterone on global brain ischemia as a result of cardiac arrest and resuscitation. Subjects: Twenty-six male Sprague-Dawley rats Interventions: Two groups of animals were randomized: 1) progesterone group (PG, n=13) and 2) saline placebo group (SG, n=13). After 8 mins of untreated ventricular fibrillation, progesterone (8 mg/kg) or saline was injected at the onset of cardiopulmonary resuscitation (CPR). Precordial compression and mechanical ventilations were initiated for 8 mins. Hemodynamics was measured at baseline, 2 and 4 hrs after the return of spontaneous circulation (ROSC). Measurements and Main Results: Electroencephalograph (EEG) was continuously recorded from baseline to the end of the 4 hr observation. Evans blue measurement was performed in 5 animals of each group to investigate blood-brain barrier (BBB) permeability. The duration of survival was evaluated during the 72 hrs after resuscitation. All rats except for one in the placebo group were successfully resuscitated. The BBB permeability was less impaired in the PG group and the recovery of EEG was earlier in the PG group. Conclusion: Administration of progesterone during CPR reduces cerebral BBB permeability and accelerates the recovery of neurological function in a rat model of prolonged VF.