TASER X26 Discharges in Swine Produce Potentially Fatal Ventricular Arrhythmias

Abstract

Objectives: Data from the authors and others suggest that TASER X26 stun devices can acutely alter cardiac function in swine. The authors hypothesized that TASER discharges degrade cardiac performance through a mechanism not involving concurrent acidosis.Methods: Using an Institutional Animal Care and Use Committee (IACUC)-approved protocol, Yorkshire pigs (25-71 kg) were anesthetized, paralyzed with succinylcholine (SCh; 2 mg ⁄ kg), and then exposed to two 40-second discharges from a TASER X26 with a transcardiac vector. Vital signs, blood chemistry, and electrolyte levels were obtained before exposure and periodically for 48 hours postdischarge. Electrocardiograms and echocardiography (echo) were performed before, during, and after the discharges. p-Values < 0.05 were considered significant.Results: Electrocardiograms were unreadable during the discharges due to electrical interference, but echo images showed unmistakably that cardiac rhythm was captured immediately at a rate of 301 ± 18 beats ⁄ min (n = 8) in all animals tested. Capture continued for the duration of the discharge and in one animal degenerated into fatal ventricular fibrillation (VF). In the remaining animals, ventricular tachycardia (VT) occurred postdischarge for 1-17 seconds, whereupon sinus rhythm was regained spontaneously. Blood chemistry values and vital signs were minimally altered postdischarge and no significant acidosis was seen.Conclusions: Extreme acid-base disturbances usually seen after lengthy TASER discharges were absent with SCh, but TASER X26 discharges immediately and invariably produced myocardial capture. This usually reverted spontaneously to sinus rhythm postdischarge, but fatal VF was seen in one animal. Thus, in the absence of systemic acidosis, lengthy transcardiac TASER X26 discharges (2 · 40 seconds) captured myocardial rhythm, potentially resulting in VT or VF in swine.ACADEMIC EMERGENCY MEDICINE 2008; 15:66-73 ª

Sudden Cardiac Arrest and Death Following Application of Shocks From a TASER Electronic Control Device

“…25 It is clear from the information cited above that an ECD shock to the chest can produce cardiac electrical capture at rapid rates in animals and humans. [11][12][13][14][15][16][17][18] Furthermore, it is clear that VF has been documented as early as 2 minutes after an ECD shock to humans. 3,5 What is lacking is the actual ECG recording of VF induction during an ECD shock in humans, a practical impossibility unless it fortuitously occurred in an individual with a recording device already in place.…”

“…20 In addition to the importance of probe location, longerduration shocks at normal TASER X26 outputs appear more likely to induce VF. 13,14 Although it is possible that body size might influence cardiac capture and development of VF, clearly big people can still develop VF from an ECD shock (see the Table).…”

“…However, ECD-induced VT and VF have been clearly and repeatedly shown in pigs. [11][12][13][14][15]19 In 1 example, intravenous epinephrine in an anesthetized pig, infused at a concentration that increased the spontaneous sinus rate 50% to replicate the clinical "fight or flight" situation, improved the TASER model X26 electrical capture ratio from 3:1 to 2:1 and resulted in VF induction. 12 Thus, from the pig studies, a likely clinical scenario is that ECD induced cardiac electrical capture at rates of 200 to 240 bpm (a 6:1-4:1 ratio), as already shown in humans.…”

“…The threshold for transthoracic cardiac electrical capture is 100 microcoulombs, 10 which is the output of the TASER model X26. 1 Studies in pigs, [11][12][13][14][15] sheep, 16 and humans 17 established that transthoracic shocks from the TASER model X26 or a new prototype ECD 18 caused cardiac electrical capture. In addition, porcine research showed that such electrical capture could provoke VF at normal [12][13][14][15] or higher-than-normal 11 TASER model X26 outputs.…”

TASER Electronic Control Devices Can Cause Cardiac Arrest in Humans

“…youtube.com/watch?v=PxcXwk4UHm4). The second study 16 showed that succinylcholine eliminated the acidosis after the If our data can be translated to humans, then ventricular rhythm may be captured and postdischarge dysrhythmias or VF may occur. Such transcardiac vectors should be avoided when possible and the potential for deterioration of the cardiac rhythm to VF in the field should be considered….Users should be trained to recognize the possible cardiac effects and be prepared to use automated external defibrillators and cardiopulmonary resuscitation maneuvers when needed.…”