Immediate cardiovascular effects of the Taser X26 conducted electrical weapon

Elektroschockdistanzwaffen Taser® X2 und T7

Die medizinische Beurteilung von Verletzungen und potenzieller todesursächlicher Relevanz einer Stromexposition durch eine Elektroschockdistanzwaffe beschränkt sich nicht allein auf die situativen Gegebenheiten und die morphologische Befunderhebung, sondern beinhaltet auch eine intensive Analyse polizeilicher Ermittlungen und die Auswertung von Zeugenaussagen sowie vorangegangener medizinischer Maßnahmen. Insbesondere bei zeitlich relevanter Nähe zwischen Exposition und Todeseintritt muss die Wirkung der übertragenen Stromimpulse in Zusammenhang mit der meist komplexen Einsatzsituation und der medizinischen Vorgeschichte des Geschädigten beurteilt werden. Ein detailliertes Wissen über die konkrete und auch abstrakte Wirkungsweise, Wirksamkeit und Risiken von Elektroschockdistanzwaffen ist hierfür unabdingbar.

Human Health Risks of Conducted Electrical Weapon Exposure: A Systematic Review

IMPORTANCE

Conducted electrical weapons (CEWs) are used broadly as a less-lethal force option for police officers. However, there is no clear picture of the possible health risks in humans on the basis of rigorously assessed scientific evidence from the international peer-reviewed literature.

OBJECTIVE

To synthesize and systematically evaluate the strength of published evidence for an association between exposure to different models of CEWs and adverse acute as well as chronic conditions.

EVIDENCE REVIEW

Following a preregistered review protocol, the literature search strategy was based on a search of reviews published between January 1, 2000, and April 24, 2020, of PubMed, MEDLINE, EMBASE, Web of Science, PsycINFO, and Cochrane Library, as well as relevant online databases and bibliographic sources, such as reference sections of recent publications. The identified studies were independently assessed in terms of scope, relevance, methodologic bias, and quality. Peer-reviewed publications of human studies were included, using original data and with a focus on the use of taser CEWs in the context of law enforcement. Eligible studies examined clearly defined health outcomes as dependent variables following exposure to a CEW. The review followed the relevant sections of the Preferred Reporting Items for Systematic Reviews and Meta-analyses reporting guideline. A meta-analysis could not be conducted.

FINDINGS

Of the 1081 unique records screened, 33 relevant studies were identified, all of them of experimental design and conducted in the US. Eleven studies had a low risk of bias and 22 had a higher bias risk. Studies focused on outcomes such as physiologic stress responses, heart rate, blood pressure, arrhythmias, or cognitive performance. Independently of bias risk, the studies reported few or no acute health problems, apart from the wounds caused by the darts. Furthermore, no long-term outcomes were studied. Most of the studies were performed on healthy, physically fit individuals (eg, police officers) in a controlled setting, with short exposure duration (5 seconds). Half of the studies, mainly those with a higher risk of bias, were at least partly funded by the manufacturer.

CONCLUSIONS AND RELEVANCE

Based on the findings of the reviewed studies, the risk for adverse health outcomes due to CEW exposure can be currently estimated as low. However, most of the reviewed studies had methodologic limitations. Considering that recruited participants were not representative of the population that usually encounters a CEW deployment, it is not possible to draw conclusions regarding exposure outcomes in potentially vulnerable populations or high-risk groups, such as those under the influence of substances.

[The topical problems of the application of the TASER electroshock devices]

The objective of the present study was the analysis of publications in the foreign medical literature concerning the problems of safety, clinical diagnostics, pathological morphology, and treatment of the patients subjected to the impact by various models of the TASER electroshock devices. The materials for this article were borrowed from the available Internet resources and libraries. The methods of scientific analysis were employed to follow up the dynamics of publication and to determine the number of publications on the issues of interest. The main attention was given to the overview of the subject matter of scientific research and experiments. The review covers 74 foreign articles presenting the discussion of various conditions and circumstances of the action of various types of the TASER electroshock devices (ESD) on the man with special reference to their effectiveness and safety as confirmed by numerous experimental impacts on the volunteers and animals. It is shown that the dynamics of relevant publications in the foreign scientific periodicals gives evidence of the strong interest shown by the specialists in various scientific disciplines to the problem of safety of various models of the TASER electroshock devices. The largest number of the articles (60 or 81.1%) published during the period covered by the present study were submitted by the American authors describing their experiments involving the volunteers, anthropometric dummies, and human corpses (n=38 or 51%). The subject matter of these publications included the forensic medical evaluation of the lethal outcomes of the application of the TASER electroshock devices with the related technical problems and characteristic of various ESD models. Despite the extensive studies on the volunteers and the experimental animals, the authors of the publications failed to present direct and conclusive evidence of the lethal consequences of the application of the TASER electroshock devices (ESD) on the man. Some of them recommend to prohibit (or restrict whenever possible) the targeted application of the electric shock weapons to the thoracic region. Experiments on the animals have demonstrated the possibility of development of cardiovascular and respiratory complications following the application of the TASER X2 electroshock devices operating at a frequency of 40 Hz during 30 minutes. The clinical and laboratory studies with the participation of the volunteers in an alcoholic intoxication condition have confirmed the long-term increase in the blood lactate levels under the influence of the electric shocking weapons. The analogous data suggesting the development of pronounced acidosis under effect of the TASER X2 electroshock devices due to the elevation of the lactate concentration in the venous blood have been obtained in the animal experiments. The studies of humans in a narcotic intoxication condition failed to provide direct evidence of induction of psychic disorders in the form of an acute confusional state (delirium) under the influence of the TASER electroshock devices. The evaluation of changes in the skin cover in the form of the punctured or contused wounds in the victims of the application of the electroshock gun projectiles did not revealed any specific signs of the local electrical action.

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.

Physiologic effects of a new-generation conducted electrical weapon on human volunteers

BACKGROUND

Conducted electrical weapons (CEWs) are used by law enforcement to restrain or repel potentially violent persons. The TASER X2 CEW is a next-generation device with new technology, including new electrical waveform and output specifications. It has not previously been studied in humans.

OBJECTIVE

The objective of this study was to evaluate the human physiologic effect of a new-generation CEW.

METHODS

This was a prospective, observational human study. Volunteers received a 10-s exposure via deployed probes from an X2 CEW in the abdomen and upper thigh. Measured data included vital signs; 12-lead electrocardiograms; and blood serum biomarkers before, immediately after, and 24 h post exposure. Biomarkers measured included pH, lactate, potassium, creatine kinase (CK), and troponin-I. Real-time spirometry and echocardiography were performed before, during, and after the exposure.

RESULTS

Ten volunteers completed the study. There were no important changes in vital signs or potassium. Median increase in lactate as a consequence of the exposure was 1.2 mg/dL (range 0.6-2.8 mg/dL). Median change in pH was -0.031 (range -0.011 to -0.067). No subject had a positive troponin. Median change in CK at 24 h was 313 ng/mL (range -40 to 3418 ng/mL). There was no evidence of respiratory impairment. Baseline median minute ventilation was 14.2 L/min, increased to 21.6 L/min intra-exposure (p = 0.05), and remained elevated at 21.6 L/min post exposure (p = 0.01).

CONCLUSIONS

There was no evidence of dangerous physiology found in the measured parameters. The physiologic effects of the X2 CEW are similar to older-generation CEWs. We encourage further study to validate these results.

Conducted electrical weapon (TASER) use against minors: a shocking analysis

OBJECTIVE

Conducted electrical weapons (CEWs) such as the TASER are often used by law enforcement (LE) personnel during suspect apprehension. Previous studies have reported an excellent safety profile and few adverse outcomes with CEW use in adults. We analyzed the safety and injury profile of CEWs when used during LE apprehension of children and adolescents, a potentially vulnerable population.

METHODS

Consecutive CEW uses by LE officers against criminal suspects were tracked at 10 LE agencies and entered into a database as part of an ongoing multicenter injury surveillance program. All CEW uses against minors younger than 18 years were retrieved for analysis. Primary outcomes included the incidence and type of mild, moderate, and severe CEW-related injury, as assessed by physician reviewers in each case. Ultimate outcomes, suspect demographics, and circumstances surrounding LE involvement are reported secondarily.

RESULTS

Of 2026 consecutive CEW uses, 100 (4.9%) were uses against minor suspects. Suspects ranged from 13 to 17 years, with a mean age of 16.1 (SD, 0.99) years (median, 16 years). There were no significant (moderate or severe) injuries reported (0%; 97.5% confidence interval, 0.0%-3.6%). Twenty suspects (20%; 95% confidence interval, 12.7%-29.1%) were noted to sustain 34 mild injuries. The majority of these injuries (67.6%) were expected superficial punctures from CEW probes. Other mild injuries included superficial abrasions and contusions in 7 cases (7%).

CONCLUSIONS

None of the minor suspects studied sustained significant injury, and only 20% reported minor injuries, mostly from the expected probe puncture sites. These data suggest that adolescents are not at a substantially higher risk than adults for serious injuries after CEW use.

Funding source and author affiliation in TASER research are strongly associated with a conclusion of device safety

BACKGROUND

Controversy exists regarding the safety of electrical stun guns (TASERs). Much of the research on TASERs is funded by the maker of the device and, therefore, could be biased. We sought to determine if funding source or author affiliation is associated with TASER research conclusions.

METHODS

MEDLINE was searched for TASER or electrical stun gun to identify relevant studies. All human and animal studies published up to September 01, 2010, were included. Reviews, editorials, letters, and case reports were excluded from the analysis. Two independent reviewers blinded to this study hypothesis evaluated each article with regard to conclusions of TASER safety.

RESULTS

Fifty studies were reviewed: 32 (64%) were human studies and 18 (36%) were animal studies. Twenty-three (46%) studies were funded by TASER International or written by an author affiliated with the company. Of these, 22 (96%) concluded that TASERs are unlikely harmful (26%) or not harmful (70%). In contrast, of the 22 studies not affiliated with TASER, 15 (55%) concluded that TASERs are unlikely harmful (29%) or not harmful (26%). A study with any affiliation with TASER International had nearly 18 times higher odds to conclude that the TASER is likely safe as compared with studies without such affiliation (odds ratio 17.6, 95% CI 2.1-150.1, P = .001).

CONCLUSIONS

Studies funded by TASER and/or written by an author affiliated with the company are substantially more likely to conclude that TASERs are safe. Research supported by TASER International may thus be significantly biased in favor of TASER safety.

Emergency department evaluation after conducted energy weapon use: review of the literature for the clinician

BACKGROUND

Conductive energy weapons (CEWs) are used daily by law enforcement, and patients are often brought to an emergency department (ED) for medical clearance.

STUDY OBJECTIVES

To review the medical literature on the topic of CEWs and to offer evidence-based recommendations to Emergency Physicians for evaluation and treatment of patients who have received a CEW exposure.

METHODS

A MEDLINE literature search from 1988 to 2010 was performed and limited to human studies published from January 1988 to January 20, 2010 for English language articles with the following keywords: TASER, conductive energy device(s), electronic weapon(s), conductive energy weapon(s), non-lethal weapon(s), conducted energy device(s), conducted energy weapon(s), conductive electronic device(s), and electronic control device(s). Studies identified then underwent a structured review from which results could be evaluated.

RESULTS

There were 140 articles on CEWs screened, and 20 appropriate articles were rigorously reviewed and recommendations given. These studies did not report any evidence of dangerous laboratory abnormalities, physiologic changes, or immediate or delayed cardiac ischemia or dysrhythmias after exposure to CEW electrical discharges of up to 15 s.

CONCLUSIONS

The current medical literature does not support routine performance of laboratory studies, electrocardiograms, or prolonged ED observation or hospitalization for ongoing cardiac monitoring after CEW exposure in an otherwise asymptomatic awake and alert patient.