Demonstration of a Mechanical External Biventricular Assist Device for Resuscitative Thoracotomy

Resuscitative thoracotomy, a high-risk procedure involving open heart massage, serves as a last resort for life-threatening conditions like penetrating chest wounds, severe blunt trauma, or surgery-related cardiac arrest. However, its success rate remains low, even when primarily carried out by highly trained specialists. This research investigates the potential of an external biventricular assist device (BiVAD). By replacing open heart massage with our BiVAD device during resuscitative thoracotomy, we aim to achieve sufficient cardiac output, maintain physiological pressure levels, and potentially improve patient survival in these critical situations.

The proposed BiVAD system features a 3D printed patch design for direct cardiac attachment, an actuation device, and a vacuum pump. The straightforward design allows quick application in emergency situations. The BiVAD system was tested in an in vitro hydraulic mock circulation, utilizing a silicone heart. Three actuation modes were tested for proof-of-concept: manual patch actuation, standard cardiac hand massage, and utilizing full capabilities of our BiVAD patch system with actuation device operation. Overall performance was assessed on ventricular pressure and flow rate data.

Focusing on achieving the optimal cardiac output of 1.5 L/min (critical for patient survival), we tested our patch system against cardiac hand massage at a fixed rate of 60 bpm. The results include raw and statistically evaluated flow rate and pressure measurements for both the left and the right ventricle. Notably, our BiVAD system not only achieved to operate in the range of required cardiac output but also significantly reduced peak pressure in both ventricles compared to standard cardiac hand massage.

This initial evaluation using a silicone heart model demonstrates the potential of our BiVAD system to achieve sufficient cardiac output while reducing peak pressure compared to cardiac hand massage. Further development holds promise for effective cardiac support in resuscitative thoracotomy.