Reduction of defibrillator shock related pain by a tetanizing prepulse

Reduction of defibrillator shock related pain by a tetanizing prepulse

Reduction of defibrillator shock related pain: Defibrillator shocks are painful, mostly due to the associated skeletal muscle stimulation. A novel method for minimizing defibrillator shock associated pain has been proposed by a porcine study [1]. A high frequency alternating current prepulse is delivered just before the actual defibrillator shock in this model. Limb acceleration and rate of force development was used as a surrogate of pain in the animal model. There was no difference in the defibrillation threshold with true biphasic shocks and shocks preceded by a tetanizing prepulse. Still there was almost three fourth reduction in peak acceleration and rate of force development with a prepulse. This would suggest that implantable defibrillator shock associated pain could be reduced by a tetanizing prepulse. Of course human studies are needed before actual clinical implementation.

The exact physiology underlying defibrillator shock related pain is not fully understood. It could be direct nerve stimulation and/or secondary nociception following skeletal muscle stimulation. The latter possibility is suggested with reports of patients complaining of persisting muscle soreness for a few days after a shock.

Reference

1. Hunter DW, Tandri H, Halperin H, Tung L, Berger RD. Tetanizing prepulse: A novel strategy to mitigate implantable cardioverter-defibrillator shock-related pain. Heart Rhythm. Heart Rhythm. 2016 May;13(5):1142-1148.