Pralidoxime administered during cardiopulmonary resuscitation facilitates successful resuscitation in a pig model of cardiac arrest.

Pralidoxime is a common antidote for organophosphate poisoning; however, studies have also reported pralidoxime's pressor effect, which may facilitate the restoration of spontaneous circulation (ROSC) after cardiac arrest by improving coronary perfusion pressure (CPP). We investigated the immediate cardiovascular effects of pralidoxime in anaesthetised normal rats and the effects of pralidoxime administration during cardiopulmonary resuscitation (CPR) in a pig model of cardiac arrest. To evaluate the immediate cardiovascular effects of pralidoxime, seven anaesthetised normal rats received saline or pralidoxime (20 mg/kg) in a randomised crossover design, and the responses were determined using the conductance catheter technique. To evaluate the effects of pralidoxime administration during CPR, 22 pigs randomly received either 80 mg/kg of pralidoxime or an equivalent volume of saline during CPR. In the rats, pralidoxime significantly increased arterial pressure than saline (P = 0.044). The peak effect on arterial pressure was observed in the first minute. In a pig model of cardiac arrest, CPP during CPR was higher in the pralidoxime group than in the control group (P = 0.002). ROSC was attained in three animals (27.3%) in the control group and nine animals (81.8%) in the pralidoxime group (P = 0.010). Three animals (27.3%) in the control group and eight animals (72.2%) in the pralidoxime group survived the 6-hour period (P = 0.033). In conclusion, pralidoxime had a rapid onset of pressor effect. Pralidoxime administered during CPR led to significantly higher rates of ROSC and 6-hour survival by improving CPP in a pig model.