Asphyxial death during prone restraint revisited: a report of 21 cases

Police arrest-related death: about four cases and review of the literature

Unexpected deaths may occur in individuals during a police arrest. These individuals usually have had both physical and emotional exertion, associated or not with agitation and restraint by police. Further investigations in these cases often show an impregnation with drugs. Autopsy findings may raise medico-legal problems in these cases.We report four cases of deaths during police arrest in which multiple factors contributed to the death. In the first two cases, there was a combination of emotional and physical stress due to police pursuit and, the presence of mechanical asphyxia. We noticed the presence of cannabis and amphetamine; however, we couldn't relate the death to a drug intoxication. In the third case, the deceased lost consciousness when he was arrested by the police with no link to the intervention of law enforcement authorities. Death in this case was due to sepsis complicating endocarditis. The fourth case reports a rare cause of asphyxia that can occur in a police arrest related to a drug package. Death was due to upper airway obstruction in this case.The forensic pathologist should take into consideration every factor when explaining these deaths. Thorough autopsy and investigations are critical to understand the cause and circumstances of death.

Philemon and Baucis death: a literature review

Double death, i.e., two bodies at a scene, is relatively rare. The double death from natural causes of two close persons is called Philemon and Baucis death in the medicolegal literature. Despite being mentioned for the first time more than 50 years ago, all detailed case reports on this case constellation are from the last 15 years. A comprehensive review of the literature on this phenomenon has not yet been published. In this article, we review the available literature on Philemon and Baucis death. Pathophysiologically, it can be assumed that this phenomenon is a sub-form of so-called psychogenic death. Therefore, we equally review the literature on sudden cardiac death due to acute psychological stress.

Bodies of evidence: The 'Excited Delirium Syndrome' and the epistemology of cause-of-death inquiry

"Excited Delirium Syndrome" (ExDS) is a controversial diagnosis. The supposed syndrome is sometimes considered to be a potential cause of death. However, it has been argued that its sole purpose is to cover up excessive police violence because it is mainly used to explain deaths of individuals in custody. In this paper, we examine the epistemic conditions giving rise to the controversial diagnosis by discussing the relation between causal hypotheses, evidence, and data in forensic medicine. We argue that the practitioners' social context affects causal inquiry through background assumptions that enter inquiry at multiple stages. This analysis serves to better understand the wide usage of the controversial diagnosis of ExDS.

Oleoresin Capsicum (OC) Spray: An Assessment of Respiratory Health and its Management Following Accidental and Deliberate Exposures

Introduced into law enforcement in 1976, the oleoresin capsicum (OC) spray has been labeled as one of the most significant and radical developments in law enforcement. However, epidemiological research on OC health effects is deficient, receiving little public support. The major responses to acute exposure to OC spray can be found in the pulmonary system. The molecular mechanism(s) involved in the action of capsaicinoids, the active constituents in OC, are complex cascades of reactions which end up in necrosis or apoptosis. OC may also damage and deplete biological redox systems in the epithelial lining fluids and within cells and mitochondria, modifying structural proteins and nucleic acids and leading to enzyme inactivation. Since there are no characteristic laboratory tests available for identification or confirmation of OC exposure, and on the basis of prevailing data, reassessment of the health risks of OC exposures in vulnerable populations and in-depth study of the molecular mechanics of receptors is the need of the hour for the development of effective countermeasures. This review aims to consider evidence for adverse effects of OC spray used in ways comparable to their application by law enforcement personnel and civilians, with possible treatment recommendations that are precedent for improved management.

Response to "Scrutinizing the causal link between excited delirium syndrome and restraint - a commentary on: 'The role of restraint in fatal excited delirium: a research synthesis and pooled analysis' by E.M.F. Strömmer, W. Leith, M.P. Zeegers and M.D. Freeman"

de Boer et al. criticize the conclusions in our 2020 paper on the validity of Excited Delirium Syndrome (ExDS) as "egregiously misleading." Our conclusion was that there "is no existing evidence that indicates that ExDS is inherently lethal in the absence of aggressive restraint." The basis for de Boer and colleague's criticism of our paper is that the ExDS literature does not provide an unbiased view of the lethality of the condition, and therefore the true epidemiologic features of ExDS cannot be determined from what has been published. The criticism is unrelated to the goals or methods of the study, however. Our stated purpose was to investigate "how the term ExDS has evolved in the literature and been endowed with a uniquely lethal quality," and whether there is "evidence for ExDS as a unique cause of a death that would have occurred regardless of restraint, or a label used when a restrained and agitated person dies, and which erroneously directs attention away from the role of restraint in explaining the death." We cannot fathom how de Boer et al. missed this clearly stated description of the study rationale, or why they would endorse a series of fallacious and meaningless claims that gave the appearance that they failed to grasp the basic design of the study. We do acknowledge and thank these authors for pointing out 3 minor citation errors and an equally minor table formatting error (neither of which altered the reported results and conclusions in the slightest), however.

Prone restraint death: Possible role of the Valsalva maneuver

There is an on-going debate about the safety of prone restraint and the exact role of the prone position in physical restraint death. Cardiac arrest in prone restraint death is essentially the end-result of a violent physical altercation wherein a combative individual suddenly loses consciousness while trying to counteract an opposing force. The direct correlations of increased static weight force with decreased inferior vena cava diameter, decreased cardiac output, and decreased stroke volume in prone restraint studies suggest that decreased venous return and decreased cardiac output could have a significant role to play in prone restraint death. Although the degree of changes observed in those studies might not be sufficient to cause cardiac arrest, they could predispose people who instinctively try to free themselves of the restraints to severe complications. The Valsalva maneuver, or forceful expiration against a closed airway, is frequently performed spontaneously in daily activities involving straining and resistance exercise, but has never been considered in restraint death. Pre-existing diminished venous return could increase the risk of major complications in individuals performing the Valsalva maneuver. A substantial decrease in venous return and cardiac output could increase the risk of cerebral hypoperfusion, loss of consciousness, hypoventilation, and sudden death. By increasing the risk of increased intra-abdominal pressure and its negative effect on venous return, high body mass index may be a significant risk factor in prone restraint death. The Valsalva maneuver may have different roles in prone restraint cardiac arrest and might be overlooked in prone restraint death.

Evaluation of the ventilatory effects on human subjects in prolonged hip-flexed/head-down restraint position

BACKGROUND

The restraint chair is a tool used by law enforcement and correction personnel to control aggressive, agitated individuals. When initiating its use, subjects are often placed in a hip-flexed/head-down (HFHD) position to remove handcuffs. Usually, this period of time is less than two minutes but can become more prolonged in particularly agitated patients. Some have proposed this positioning limits ventilation and can result in asphyxia. The aim of this study is to evaluate if a prolonged HFHD restraint position causes significant ventilatory compromise.

METHODS

Subjects exercised on a stationary bicycle until they reached 85% of their predicted maximal heart rate. They were then handcuffed with their hands behind their back and placed into a HFHD seated position for five minutes. The primary outcome measurement was maximal voluntary ventilation (MVV). This was measured at baseline, after initial placement into the HFHD position, and after five minutes of being in the position while still maintaining the HFHD position. Baseline measurements were compared with final measurements for statistically significant differences.

RESULTS

We analyzed data for 15 subjects. Subjects had a mean MVV of 165.3 L/min at baseline, 157.8 L/min after initially being placed into the HFHD position, and a mean of 138.7 L/min after 5 min in the position. The mean baseline % predicted MVV was 115%; after 5 min in the HFHD position the mean was 96%. This 19% absolute difference was statistically significant (p = 0.001).

CONCLUSIONS

In healthy seated male subjects with recent exertion, up to five minutes in a HFHD position results in a small decrease in MVV compared with baseline MVV levels. Even with this decrease, mean MVV levels were still 96% of predicted after five minutes. Though a measurable decrease was found, there was no clinically significant change that would support that this positioning would lead to asphyxia over a five-minute time period.

Prone restraint cardiac arrest: A comprehensive review of the scientific literature and an explanation of the physiology

Deaths occurring among agitated or violent individuals subjected to physical restraint have been attributed to positional asphyxia. Restraint in the prone position has been shown to alter respiratory and cardiac physiology, although this is thought not to be to the degree that would cause asphyxia in a healthy, adult individual. This comprehensive review identifies and summarizes the current scientific literature on prone position and restraint, including experiments that assess physiology on individuals restrained in a prone position. Some of these experimental approaches have attempted to replicate situations in which prone restraint would be used. Overall, most findings revealed that individuals subjected to physical prone restraint experienced a decrease in ventilation and/or cardiac output (CO) in prone restraint. Metabolic acidosis is noted with increased physical activity, in restraint-associated cardiac arrest and simulated encounters. A decrease in ventilation and CO can significantly worsen acidosis and hemodynamics. Given these findings, deaths associated with prone physical restraint are not the direct result of asphyxia but are due to cardiac arrest secondary to metabolic acidosis compounded by inadequate ventilation and reduced CO. As such, the cause of death in these circumstances would be more aptly referred to as "prone restraint cardiac arrest" as opposed to "restraint asphyxia" or "positional asphyxia."

Postmortem Otorrhagia in Positional Asphyxia

Otorrhagia is generally associated with basilar skull fractures or diving accidents. In routine forensic medical practice, an accurate knowledge of the etiology of otorrhagia may have a key role to distinguish between traumatic and atraumatic causes and accidental, homicidal, or suicidal manners. The authors present the case of an unusual cause of atraumatic otorrhagia occurred in an elderly farmer found dead in a barn. He remained entrapped in a narrow tunnel created by some hay bales. The autopsy findings revealed only an intense polyvisceral congestion and subpleural petechiae, with no signs of traumatic injuries and no fractures of skull base or temporal pyramid. The cause of death was determined to be positional asphyxia, and the manner of death was deemed accidental. In fact, the head-down position resulted in diaphragm compression causing respiratory failure in combination with the stasis of the upper venous circle districts. Mechanical and gravitational forces related to upside-down position and increased vascular pressure also caused postmortem otorrhagia. In this case, the death scene investigation and circumstantial information allowed for reconstruction of the unique dynamics of the death. At the death scene, the position of the corpse must be accurately investigated because it can explain some cadaveric findings such as the ear bleeding or other markers of increased cephalic venous pressure like pink teeth, facial and conjunctival petechiae, or Tardieu spots. Therefore, forensic pathologists should consider that ear bleeding in dead bodies is not always the evidence of severe head blunt trauma or diving accidents, but it might be a postmortem phenomenon mostly related to body position.

The use of mechanical restraint in Pacific Rim countries: an international epidemiological study

AIMS

The use of mechanical restraint is a challenging area for psychiatry. Although mechanical restraint remains accepted as standard practice in some regions, there are ethical, legal and medical reasons to minimise or abolish its use. These concerns have intensified following the Convention on the Rights of Persons with Disabilities. Despite national policies to reduce use, the reporting of mechanical restraint has been poor, hampering a reasonable understanding of the epidemiology of restraint. This paper aims to develop a consistent measure of mechanical restraint and compare the measure within and across countries in the Pacific Rim.

METHODS

We used the publicly available data from four Pacific Rim countries (Australia, New Zealand, Japan and the United States) to compare and contrast the reported rates of mechanical restraint. Summary measures were computed so as to enable international comparisons. Variation within each jurisdiction was also analysed.

RESULTS

International rates of mechanical restraint in 2017 varied from 0.03 (New Zealand) to 98.9 (Japan) restraint events per million population per day, a variation greater than 3000-fold. Restraint in Australia (0.17 events per million) and the United States (0.37 events per million) fell between these two extremes. Variation as measured by restraint events per 1000 bed-days was less extreme but still substantial. Within all four countries there was also significant variation in restraint across districts. Variation across time did not show a steady reduction in restraint in any country during the period for which data were available (starting from 2003 at the earliest).

CONCLUSIONS

Policies to reduce or abolish mechanical restraint do not appear to be effecting change. It is improbable that the variation in restraint within the four examined Pacific Rim countries is accountable for by psychopathology. Greater efforts at reporting, monitoring and carrying out interventions to achieve the stated aim of reducing restraint are urgently needed.

The role of restraint in fatal excited delirium: a research synthesis and pooled analysis

The purpose of the present study was to perform a comprehensive scientific literature review and pooled data risk factor analysis of excited delirium syndrome (ExDS) and agitated delirium (AgDS). All cases of ExDS or AgDS described individually in the literature published before April 23, 2020 were used to create a database of cases, including demographics, use of force, drug intoxication, mental illness, and survival outcome. Odds ratios were used to quantify the association between death and diagnosis (ExDS vs. AgDS) across the covariates. There were 61 articles describing 168 cases of ExDS or AgDS, of which 104 (62%) were fatal. ExDS was diagnosed in 120 (71%) cases, and AgDS in 48 (29%). Fatalities were more likely to be diagnosed as ExDS (OR: 9.9, p < 0.0001). Aggressive restraint (i.e. manhandling, handcuffs, and hobble ties) was more common in ExDS (ORs: 4.7, 14, 29.2, respectively, p < 0.0001) and fatal cases (ORs: 7.4, 10.7, 50, respectively, p < 0.0001). Sedation was more common in AgDS and survived cases (OR:11, 25, respectively, p < 0.0001). The results of the study indicate that a diagnosis of ExDS is far more likely to be associated with both aggressive restraint and death, in comparison with AgDS. There is no evidence to support ExDS as a cause of death in the absence of restraint. These findings are at odds with previously published theories indicating that ExDS-related death is due to an occult pathophysiologic process. When death has occurred in an aggressively restrained individual who fits the profile of either ExDS or AgDS, restraint-related asphyxia must be considered a likely cause of the death.

EXCITATION study: Unexplained in-custody deaths: Evaluating biomarkers of stress and agitation

BACKGROUND

Law enforcement personnel often confront violent and dangerous individuals suffering from Excited Delirium Syndrome (ExDS) who need emergent medical evaluation and treatment to optimize the best outcomes for this potentially lethal medical emergency. These subjects typically require physical restraint and use of force measures to control them. We sought to determine if stress-related biomarkers can differentiate ExDS subjects when compared with agitation and stress under other circumstances, including agitation and extreme physical exhaustion and restraint coupled with emotional stressors.

METHODS

This was a prospective multi-center study enrolling a convenience sample of patients who presented with agitation or ExDS. Patients were enrolled from three academic emergency departments (ED), two in the United States and one in Canada. Three study groups (SG) included: SG1) patients brought to the ED with ExDS based on the use of standardized clinical criteria; SG2) ED patients with acute agitation who were not in a clinical state of ExDS but required sedation; SG3) a laboratory control group of subjects exercised to physical exhaustion, restrained, and psychologically stressed with threat of Conducted Energy Device (CED) activation. We examined a panel of stress-related biomarkers, including norepinephrine (NE), cortisol, copeptin, orexin A, and dynorphin (Dyn) from the blood of enrolled subjects.

RESULTS

A total of 82 subjects were enrolled: 31 in the agitation group, 21 in the ExDS group, and 30 in the laboratory control group. Data were analyzed, comparing the findings between ExDS and the two other groups to determine if specific stress-related biomarkers are associated with ExDS. Biomarker comparisons between subjects identified with ExDS, agitation, and control groups demonstrated that cortisol levels were more elevated in the ExDS group compared with the other groups. Orexin was only significant in ExDs (with Agitated tendency but lot of variability in the group). NE and Dyn increased as response to stress in Agitated and ExDS.

CONCLUSIONS

Cortisol levels were more elevated in subjects in the ExDS group compared with the other comparison groups and orexin was elevated in ExDS compared to controls, a trend that did not reach statistical significance in the agitated group. The clinical or diagnostic significance of these difference have yet to be defined and warrants further study.

The management of violence in general psychiatry

There is increasing concern about the level of violence within mental healthcare settings. In this article I review what is known on this subject, discuss the relationship between mental disorder and violence and summarise the different ways to prevent and manage violence. When planning strategies to prevent violence in such settings it is important to consider not only patient risk factors but also risk factors in the environment. Staff need to have all the possible techniques for managing violent behaviour available to them in order to weigh up the risks and benefits for any specific patient in any particular situation.

The problem of police-related cardiac arrest

The term "positional asphyxia" was originally used to describe the situation in which the upper airways becomes compromised by sharp angulation of the head or neck, or where the chest wall is splinted and the diaphragm is prevented from moving because of an unusual position of the body. The term was redefined in the early 1980s to describe sudden death during physical restraint of an individual who is in a prone position. A large percent of reported victims were overweight males. Most were in early middle age and manifesting psychotic behavior at the time of death. Most were reported to have unremarkable autopsies, save for the finding, in many cases, of cocaine or methamphetamine (more recently synthetic cannabinoids and cathinones as well). As no cause of death was apparent (other than non-specific signs such as pulmonary edema), it became common practice to attribute death to force exerted on the decedent's back. When experimental studies with human volunteers disproved this notion, the term "restraint asphyxia" was substituted for positional asphyxia, but with nearly the exact same meaning. No experimental study has ever determined the actual amount of force necessary to cause asphyxia by force applied to the back (although the range of required static force is known), nor the duration for which it must be applied. This review discusses the epidemiology and the evidence for and against the theory of "restraint/positional" asphyxia. It also considers alternative theories of causation, including the findings of studies suggesting that cardiac channelopathies/cardiomyopathies may explain many cases of ARD.

Sudden cardiac death with stress and restraint: The association with sudden adult death syndrome, cardiomyopathy and coronary artery disease

OBJECTIVE

The aim of this study was to report on sudden cardiac death (SCD) during or immediately after a stressful event in a predominately young cohort.

METHODS

This study used retrospective non-case-controlled analysis. A total of 110 cases of SCD in relation to a stressful event such as altercation (45%), physical restraint (31%) in police custody (10%), exams/school/job stress (7.27%), receiving bad news (4%), or a car accident without injuries (2.73%) were retrospectively investigated. The majority of the subjects experiencing SCD were male (80.91%). The mean age was 36 ± 16 years (range 5-82 years). Twenty-three cases (20.91%) were psychiatric patients on antipsychotic medication.

RESULTS

Fifty-three per cent of cases died with a negative autopsy and a morphologically normal heart, indicating sudden adult death which is linked to cardiac channelopathies predisposing to stress-induced SCD. Cardiomyopathy was found in 16 (14.5%) patients and coronary artery pathology in 19 (17%) patients, with atherosclerosis predominating in older patients.

CONCLUSIONS

This study highlights SCD during psychological stress, mostly in young males where the sudden death occurred in the absence of structural heart disease. This may reflect the proarrhythmic potential of high catecholamines on the structurally normal heart in those genetically predisposed because of cardiac channelopathy. Structural cardiomyopathies and coronary artery disease also feature prominently. Cases of SCD associated with altercation and restraint receive mass media attention especially when police/other governmental bodies are involved. This study highlights the rare but important risk of SCD associated with psychological stress and restraint in morphologically normal hearts and the importance of an expert cardiac opinion where prolonged criminal investigations and medico-legal issues often ensue.

Deaths in police custody

Deaths in police custody often attract a huge amount of public interest and are frequently associated with controversy related to causation. While systematic investigations of deaths in police custody are currently available for countries in Europe, North America and Australia, the different inclusion and exclusion criteria and the lack of a uniform definition limits their comparability. Rates of death vary by age and gender with some similarities across different countries and continents. The male dominance is essentially due to the fact that around the world women are much less frequently taken into police custody than men. Similarly, in the U.S., the most common cause of custody death was natural illness and disease progression such as heart disease and cancer; along with high rates of suicide deaths. In most European countries there is a considerable dominance of non-natural deaths. The causes of death are dominated by alcohol, drugs and medications, but suicide, injury and trauma are also common. Deaths in custody require careful investigation to determine causality as well as culpability when appropriate. While many deaths may not be preventable, some are. Further systematic research of this issue, including detailed analyses and investigations of such cases, is necessary to develop general and specific preventative measures to reduce the risk of death in the custody population.

Investigation of Deaths Temporally Associated with Law Enforcement Apprehension

The investigation of a death that occurs in custody requires a careful and methodical approach since concerns of police or institutional misconduct may be raised. The medicolegal official charged with the investigation and ultimate certification of death bears heavy responsibility to the decedent's family, the public, law enforcement and other institutions. A wide variety of causes of death and manners of death are seen in these deaths. This paper reviews causes, mechanisms, manners, findings, and evaluation of persons who have died in temporal relation to legal apprehension.

The physiological impact of upper limb position in prone restraint

Deaths occurring during and/or in close proximity to physical restraint have been attributed to positional asphyxia. This study investigated the physiological impact of three recognized prone-restraint positions with participants remaining passive. Position 3 (P3) the supported prone position (SPP) was designed to reduce the extent of pressure on the anterior chest wall (PAC) by bringing the upper limbs underneath the shoulder joint whereas for the other two positions (P1 and P2) the arms were abducted from the torso. Twenty-five adults participated. Forced vital capacity (FVC), expiratory volume in one second (FEV1), heart rate (HR) and oxygen saturations (SpO2) were taken three times in an upright seated position (baseline) and in each prone position. Mean PAC was measured at 102.6 (±24.3) and 101.4 (±24.4) mmHg for P1 and P2, respectively; however, in the SPP (P3) the mean PAC pressure reduced to 72.7 (±16.9) mmHg. All three prone-restraint positions reduced FVC and FEV1 compared with baseline (P < 0.001). P1 and P2 where the arms were abducted reduced respiratory measures equally but differed from the SPP position (P < 0.001) where PAC was significantly lower. Reductions in FVC from baseline were 16% for P1 and P2, and 11% for the SPP (P3) where PAC was ∼28% lower than in P1 and P2. Reductions in FEV1 were similar in all three prone-restraint positions and HR and SpO2 were unaffected. In summary, all prone-restraint positions restrict respiratory function but the risk associated with the position reduces as the PAC reduces.

Physical restraint and near death of a psychiatric patient

Physical restraint is used as a last resort emergency measure to calm and safeguard agitated and/or aggressive psychiatric patients. This can sometimes cause injuries, and rare fatalities have occurred. One mechanism of injury and death while in physical restraint is that of severe asphyxiation. We present the case of a hospitalized man in his mid-30s, suffering from schizophrenia. The patient was obese. He became aggressive and had to be manually restrained with a "takedown." After having been put in the prone position on the floor with a significant weight load on his body, he lost respiration and consciousness. Subsequently, he was given CPR. He regained consciousness and respiration, while the cyanosis receded in 1-2 min. Psychiatrists and pathologists should be aware that physically restraining a patient in the prone position with a significant weight load on the torso can, in rare cases, lead to asphyxiation.

A review of the scientific literature related to the adverse impact of physical restraint: gaining a clearer understanding of the physiological factors involved in cases of restraint-related death

Deaths occurring during and/or in close proximity to physical restraint have been attributed to positional asphyxia, a conclusion primarily based on opinion and reviews of case studies. This review sought to identify the current scientific evidence available in regard to the aetiology of adverse events or death occurring during or in close proximity to physical restraint. A systematic search of electronic databases (SPORTDiscus, AMED, CINAHL, MEDLINE, PsycINFO) for papers published in English, between 1980 and 2011, using keywords that related to restraint, restraint position and cardiovascular function resulted in 11 experimental papers being found for review. The term positional asphyxia as a mechanism for sudden death is poorly understood. The literature shows that restraint position has the ability to impede life-maintaining physiological functions, but that the imposed impediment is not uniform across all restraint positions/techniques. Further research is required to ascertain the risks posed by struggling during restraint for more prolonged periods of time and in different positions using varied techniques of restraint. This research should seek to and rank known or future risk factors of adverse events occurring during restraint, seeking to understand the interactions and if present the cumulative effect of these risk factors. Finally, future research should focus on populations other than apparently healthy male adults.

Restraint and seclusion use in U.S. school settings: recommendations from allied treatment disciplines

Restraint and seclusion (R&S) are high risk, emergency procedures that are used in response to perceived violent, dangerous situations. They have been employed for years in a variety of settings that serve children, such as psychiatric hospitals and residential treatment facilities, but are now being recognized as used in the public schools. The field of education has begun to examine these practices in response to national scrutiny and a Congressional investigation. The fields of mental health and child welfare were similarly scrutinized 10 years ago following national media attention and have advanced R&S practice through the adoption of a prevention framework and core strategies to prevent and reduce use. A review of the evolution of the national R&S movement, the adverse effects of these procedures, and a comprehensive approach to prevent their use with specific core strategies such as leadership, workforce development, and youth and family involvement in order to facilitate organizational culture and practice change are discussed. Proposed guidelines for R&S use in schools and systemic recommendations to promote R&S practice alignment between the child-serving service sectors are also offered.

Acidosis and catecholamine evaluation following simulated law enforcement "use of force" encounters

OBJECTIVES

Law enforcement authorities are often charged with controlling resisting suspects. These encounters sometimes result in the sudden and unexpected death of the suspect. Drug intoxication, excited delirium syndrome, or excessive uses of force are factors that are often blamed, but sometimes the mechanism of these deaths is not fully understood. It is possible that worsening acidosis or excessive catecholamine release play a part. The objective of this study was to determine the effect on markers of acidosis and catecholamines of various tasks intended to simulate common arrest-related situations.

METHODS

Subjects were assigned to one of five task groups: 1) a 150-meter sprint and wall hurdle (simulated flight from arrest); 2) 45 seconds of striking a heavy bag (simulated physical resistance); 3) a 10-second TASER X26 electronic control device exposure; 4) a fleeing and resistance exercise involving a law enforcement dog (K-9); or 5) an oleoresin capsicum (OC) exposure to the face and neck. Baseline serum pH, lactate, potassium, troponin I, catecholamines, and creatine kinase (CK) were evaluated. Serum catecholamines, pH, lactate, and potassium were sampled immediately after the task and every 2 minutes for 10 minutes posttask. Vital signs were repeated immediately after the task. Serum CK and troponin I were evaluated again at 24 hours posttask.

RESULTS

Sixty-six subjects were enrolled; four did not complete their assigned task. One subject lost the intravenous (IV) access after completing the task and did not have data collected, and one subject only received a 5-second TASER device exposure and was excluded from the study, leaving 12 subjects in each task group. The greatest changes in acidosis markers occurred in the sprint and heavy bag groups. Catecholamines increased the most in the heavy bag group and the sprint group and increased to a lesser degree in the TASER, OC, and K-9 groups. Only the sprint group showed an increase in CK at 24 hours. There were no elevations in troponin I in any group, nor any clinically important changes in potassium.

CONCLUSIONS

The simulations of physical resistance and fleeing on foot led to the greatest changes in markers of acidosis and catecholamines. These changes may be contributing or causal mechanisms in sudden custodial arrest-related deaths (ARDs). This initial work may have implications in guiding applications of force for law enforcement authorities (LEAs) when apprehending resisting subjects.

Effect of an electronic control device exposure on a methamphetamine-intoxicated animal model

OBJECTIVES

Because of the prevalence of methamphetamine abuse worldwide, it is not uncommon for subjects in law enforcement encounters to be methamphetamine-intoxicated. Methamphetamine has been present in arrest-related death cases in which an electronic control device (ECD) was used. The primary purpose of this study was to determine the cardiac effects of an ECD in a methamphetamine intoxication model.

METHODS

Sixteen anesthetized Dorset sheep (26-78 kg) received 0.0 mg/kg (control animals, n = 4), 0.5 mg/kg (n = 4), 1.0 mg/kg (n = 4), or 1.5 mg/kg (n = 4) of methamphetamine hydrochloride as a slow intravenous (IV) bolus during continuous cardiac monitoring. The animals received the following exposures in sequence from a TASER X26 ECD beginning at 30 minutes after the administration of the drug: 1) 5-second continuous exposure, 2) 15-second intermittent exposure, 3) 30-second intermittent exposure, and 4) 40-second intermittent exposure. Darts were inserted at the sternal notch and the cardiac apex, to a depth of 9 mm. Cardiac motion was determined by thoracotomy (smaller animals, < or = 32 kg) or echocardiography (larger animals, > 68 kg). Data were analyzed using descriptive statistics and chi-square tests.

RESULTS

Animals given methamphetamine demonstrated signs of methamphetamine toxicity with tachycardia, hypertension, and atrial and ventricular ectopy in the 30-minute period immediately after administration of the drug. Smaller animals (n = 8, < or = 32 kg, mean = 29.4 kg) had supraventricular dysrhythmias immediately after the ECD exposures. Larger animals (n = 8, > 68 kg, mean = 72.4) had only sinus tachycardia after the exposures. One of the smaller animals had frequent episodes of ventricular ectopy after two exposures, including runs of delayed onset, nonsustained six- to eight-beat unifocal and multifocal ventricular tachycardia that spontaneously resolved. This animal had significant ectopy prior to the exposures as well. Thoracotomy performed on three smaller animals demonstrated cardiac capture during ECD exposure consistent with previous animal studies. In the larger animals, none of the methamphetamine-intoxicated animals demonstrated cardiac capture. Two control sheep showed evidence of capture similar to the smaller animals. No ventricular fibrillation occurred after the exposure in any animal.

CONCLUSIONS

In smaller animals (32 kg or less), ECD exposure exacerbated atrial and ventricular irritability induced by methamphetamine intoxication, but this effect was not seen in larger, adult-sized animals. There were no episodes of ventricular fibrillation after exposure associated with ECD exposure in methamphetamine-intoxicated sheep.

Clinical practice guideline: 1-hour face-to-face assessment of a patient in a mechanical restraint

Face-to-face assessment within 1 hour after placing a patient in a restraint has been the standard of care following regulatory requirements set forth by the federal government in 1999. This rule, although widely followed and applauded as optimum patient care, has little evidence of a standardized format for what constitutes the examination. Health care providers agree that a face-to-face assessment is warranted; however, no set parameters exist for what constitutes the key elements of such an assessment. This clinical practice guideline offers a specific outline to follow that emphasizes the safety of the patient being placed in a mechanical restraint for a behavioral health emergency.