Numerically simulated cardiac exposure to electric current densities induced by TASER X-26 pulses in adult men

Exposures to conducted electrical weapons (including TASER® devices): how many and for how long are acceptable?

TASER(®) conducted electrical weapons (CEWs) are an important law-enforcement tool. The purposes of this study are a) to review recent literature regarding potential pathophysiological responses to applications of CEWs, and other related issues and b) to evaluate whether enough data exist to determine the acceptability of longer-duration (or repeated) exposures. This is a narrative review, using a multidisciplinary approach of analyzing reports from physiological, legal-medical, and police-strategy literature sources. In general, short-duration exposures to CEWs result in limited effects. Longer-duration or repeated exposures may be utilized with caution, although there are currently not enough data to determine the acceptability of all types of exposures. Data examined in the literature have inherent limitations. Appropriateness of specific types of CEW usage may be determined by individual police agencies, applying risk/benefit analyses unique to each organization. While more research is recommended, initial concepts of potential future long-duration or repeated CEW applications are presented.

Cardiac fibrillation risk of Taser weapons

The debate on potential health hazards associated with delivering electric discharges to incapacitated subjects, in particular on whether electric discharge weapons are lethal, less lethal or non-lethal, is still controversial. The cardiac fibrillation risks of Taser weapons X26 and X3 have been investigated by measuring the delivered high-tension pulses in dependence on load impedance. Excitation thresholds and sinus-to-Taser conversion factors have been determined by numerical modeling of endocardial, myocardial, and epicardial cells. Detailed quantitative assessment of cardiac electric exposure has been performed by numerical simulation at the normal-weighted anatomical model NORMAN. The impact of anatomical variation has been quantified at an overweight model (Visible Man), both with a spatial resolution of 2 × 2 × 2 mm voxels. Spacing and location of dart electrodes were systematically varied and the worst-case position determined. Based on volume-weighted cardiac exposure assessment, the fibrillation probability of the worst-case hit was determined to 30% (Taser X26) and 9% (Taser X3). The overall risk assessment of Taser application accounting for realistic spatial hit distributions was derived from training sessions of police officers under realistic scenarios and by accounting for the influence of body (over-)weight as well as gender. The analysis of the results showed that the overall fibrillation risk of Taser use is not negligible. It is higher at Taser X26 than at Taser X3 and amounts to about 1% for Europeans with an about 20% higher risk for Asians. Results demonstrate that enhancement as well as further reduction of fibrillation risk depends on responsible use or abuse of Taser weapons.

Cardiac fibrillation risk of TASER X-26 dart mode application

In view of reported fatalities there are still controversial discussions on whether electronic stun law enforcement weapons can cause cardiac fibrillation. Experimental data are contradictory. Simplified theoretical estimations led to a negligible low risk of 8.10(-7). With a detailed numerical-anatomical model of an adult man (NORMAN) cardiac exposure to Taser X26 high-tension pulses was quantitatively assessed and the fibrillation risk estimated by accounting for its dependence on excited volume based on 3D cardiac exposure patterns. For distance mode and worst case dart hits it could be demonstrated that cardiac exposure can reach the 30% fibrillation risk level. Risk reduces considerably if direct current flow across the heart is prevented. The overall fibrillation risk of Taser application is further reduced by the limited probability of critical hits. However, in agreement with experimental findings it is demonstrated that cardiac fibrillation risk of Taser X26 dart mode application is small, however, not negligible.