Effects of Prolonged Serum Calcium Suppression during Extra-corporeal Cardiopulmonary Resuscitation in Pigs

Background: Controlled reperfusion by monitoring blood pressure, blood flow and specific blood parameters during extracorporeal reperfusion after cardiac arrest has the potential to limit ischemia-reperfusion injury. The intracellular calcium overload as part of the ischemia-reperfusion injury provides the possibility to be counteracted by an early suppression of serum calcium with the aim of improving survival and neurological outcome.

Methods: We investigated the effects of prolonged serum calcium suppression via sodium citrate during extracorporeal resuscitation using a specific reperfusion protocol compared to a single dose approach in a porcine model after prolonged cardiac arrest. A control group (N = 10) was resuscitated after a 20-minute cardiac arrest, initially lowering intravascular calcium with the help of a single dose sodium citrate as part of the priming solution. Animals in the intervention group (N = 13) received additional sodium citrate for the first 15 minutes of reperfusion.

Results: In the control group 9/10 (90.0%) animals survived until day 7 and 7/13 (53.8%) in the intervention group (p = 0.09). Favorable neurological outcome at day 7 after cardiac arrest was observed in all surviving animals using a species-specific neurological deficit score. The coronary perfusion pressure showed to be significantly lower with a tendency to more cardiac arrhythmias in the intervention group.

Conclusion: In conclusion, prolonged reduction of serum calcium levels over the first 15 minutes of reperfusion after prolonged cardiac arrest tended to be unfavorable regarding survival and hemodynamic variables compared to a single dose approach in this animal model.

Publication History

Article published online:
13 February 2024