Theoretical possibility of ventricular fibrillation during use of TASER neuromuscular incapacitation devices

TASER devices deliver electrical pulses that temporarily incapacitate suspects. This study analyzes the theoretical possibility of ventricular fibrillation (VF) induction by TASER currents.Using finite element models (FEM), the results found that the skin, fat and anisotropic skeletal muscle layers attenuated a large portion of TASER currents, allowing just a fractional amount to penetrate transversally into deeper layers of tissue. The TASER current density reached 91 mA/cm(2), the threshold required to induce VF, at less than 14.7 mm away from the skin surface. This distance is significantly lower than the average skin-heart distance of 35 mm, as measured in subjects with a body-mass index (BMI) matched to that of typical in-custody suspects. The theoretical probability of inducing VF is significantly lower than 0.0000008, or 1:1,270,000. By comparison, the standard for basic safety and essential performance of medical electrical equipment, EN 60601-1, accepts as satisfactory a VF induction probability of 0.002, or 1:500.The results indicated that TASER devices, while not risk free, have a very low cardiac risk profile when used for suspect temporary incapacitation.