Ongoing issues with the diagnosis of excited delirium

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.

Hyperactive Delirium with Severe Agitation

Hyperactive delirium with severe agitation is a clinical syndrome of altered mental status, psychomotor agitation, and a hyperadrenergic state. The underlying pathophysiology is variable and often results from sympathomimetic abuse, psychiatric disease, sedative-hypnotic withdrawal, and metabolic derangement. Patients can go from a combative state to periarrest with little warning. Safety of the patient and of the medical providers is paramount and the emergency department should be prepared to manage these patients with adequate staffing, restraints, and pharmacologic sedatives. Treatment with benzodiazepines, antipsychotics, or ketamine is recommended, followed by airway protection, supportive measures, and cooling of hyperthermia.

Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) for the diagnosis of delirium in adults in critical care settings

BACKGROUND

Delirium is an underdiagnosed clinical syndrome typified by an acute alteration of mental state. It is an important problem in critical care and intensive care units (ICU) due to its high prevalence and its association with adverse outcomes. Delirium is a very distressing condition for patients, with a huge impact on their well-being. Diagnosis of delirium in the critical care setting is challenging. This is especially true for patients who are mechanically ventilated and are therefore unable to engage in a verbal interview. The Confusion Assessment Method for the Intensive Care Unit (CAM-ICU) is a tool specifically designed to assess for delirium in the context of ICU patients, including those on mechanical ventilation. CAM-ICU can be administered by non-specialists to give a dichotomous delirium present/absent result.

OBJECTIVES

To determine the diagnostic accuracy of the CAM-ICU for the diagnosis of delirium in adult patients in critical care units.

SEARCH METHODS

We searched MEDLINE (Ovid SP, 1946 to 8 July 2022), Embase (Ovid SP, 1982 to 8 July 2022), Web of Science Core Collection (ISI Web of Knowledge, 1945 to 8 July 2022), PsycINFO (Ovid SP, 1806 to 8 July 2022), and LILACS (BIREME, 1982 to 8 July 2022). We checked the reference lists of included studies and other resources for additional potentially relevant studies. We also searched the Health Technology Assessment database, the Cochrane Library, Aggressive Research Intelligence Facility database, WHO ICTRP, ClinicalTrials.gov, and websites of scientific associations to access any annual meetings and abstracts of conference proceedings in the field.

SELECTION CRITERIA

We included diagnostic studies enrolling adult ICU patients assessed using the CAM-ICU tool, regardless of language or publication status and reporting sufficient data on delirium diagnosis for the construction of 2 x 2 tables. Eligible studies evaluated the diagnostic performance of the CAM-ICU versus a clinical reference standard based on any iteration of the Diagnostic and Statistical Manual of Mental Disorders (DSM) criteria applied by a clinical expert.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected and collated study data. We assessed the methodological quality of studies using the QUADAS-2 tool. We used two univariate fixed-effect or random-effects models to determine summary estimates of sensitivity and specificity. We performed sensitivity analyses that excluded studies considered to be at high risk of bias and high concerns in applicability, due mainly to the target population included (e.g. patients with traumatic brain injury). We also investigated potential sources of heterogeneity, assessing the effect of reference standard diagnosis and proportion of patients ventilated.

MAIN RESULTS

We included 25 studies (2817 participants). The mean age of participants ranged from 48 to 69 years; 15 of the studies included critical care units admitting mixed populations (e.g. medical, trauma, surgery patients). The percentage of patients receiving mechanical ventilation ranged from 11.8% to 100%. The prevalence of delirium in the studies included ranged from 12.5% to 83.9%. Presence of delirium was determined by the application of DSM-IV criteria in 13 out of 25 included studies. We assessed 13 studies as at low risk of bias and low applicability concerns for all QUADAS-2 domains. The most common issue of concern was flow and timing of the tests, followed by patient selection. Overall, we estimated a pooled sensitivity of 0.78 (95% confidence interval (CI) 0.72 to 0.83) and a pooled specificity of 0.95 (95% CI 0.92 to 0.97). Sensitivity analysis restricted to studies at low risk of bias and without any applicability concerns (n = 13 studies) gave similar summary accuracy indices (sensitivity 0.80 (95% CI 0.72 to 0.86), specificity 0.95 (95% CI 0.93 to 0.97)). Subgroup analyses based on diagnostic assessment found summary estimates of sensitivity and specificity for studies using DSM-IV of 0.79 (95% CI 0.72 to 0.85) and 0.94 (95% CI 0.90 to 0.96). For studies that used DSM-5 criteria, summary estimates of sensitivity and specificity were 0.75 (95% CI 0.67 to 0.82) and 0.98 (95% CI 0.95 to 0.99). DSM criteria had no significant effect on sensitivity (P = 0.421), but the specificity for detection of delirium was higher when DSM-5 criteria were used (P = 0.024). The relative specificity comparing DSM-5 versus DSM-IV criteria was 1.05 (95% CI 1.02 to 1.08). Summary estimates of sensitivity and specificity for studies recruiting < 100% of patients with mechanical ventilation were 0.81 (95% CI 0.75 to 0.85) and 0.95 (95% CI 0.91 to 0.98). For studies that exclusively recruited patients with mechanical ventilation, summary estimates of sensitivity and specificity were 0.91 (95% CI 0.76 to 0.97) and 0.98 (95% CI 0.92 to 0.99). Although there was a suggestion of differential performance of CAM-ICU in ventilated patients, the differences were not significant in sensitivity (P = 0.316) or in specificity (P = 0.493).

AUTHORS' CONCLUSIONS

The CAM-ICU tool may have a role in the early identification of delirium, in adult patients hospitalized in intensive care units, including those on mechanical ventilation, when non-specialized, properly trained clinical personnel apply the CAM-ICU. The test is most useful for exclusion of delirium. The test may miss a proportion of patients with incident delirium, therefore in situations where detection of all delirium cases is desirable, it may be best to repeat the test or combine CAM-ICU with another assessment. Future studies should compare different screening tests proposed for bedside assessment of delirium, as this approach will reveal which tool yields superior accuracy. In addition, future studies should consider and report the flow and timing of the tests and clearly report key characteristics related to patient selection. Finally, future research should focus on the impact of CAM-ICU screening on patient outcomes.

Restraint asphyxia. An analysis of the circumstances and mechanism of death in agitated, physically restrained individuals

W ostatnich latach media coraz częściej poruszane są przypadkami śmierci młodych zazwyczaj osób, w trakcie zatrzymywania przez policję. Śmierć w tych przypadkach dotyka zazwyczaj osoby pobudzone psychoruchowo, obezwładniane z użyciem siły, a badania pośmiertne nie wykazują jednoznacznej urazowej przyczyny zgonu. Celem pracy jest próba ustalenia mechanizmu i okoliczności zgonów w trakcie obezwładniania osób pobudzonych psychoruchowo. Analizie poddano przypadki opiniowane od 2010 roku, zarówno jako sekcje zwłok, jak i oceniane na podstawie materiału aktowego. W analizowanym okresie ZMS w Krakowie wydał opinie w 10 tego typu przypadkach, w dziewięciu na podstawie własnych sekcji zwłok, w jednym na podstawie materiału aktowego. We wszystkich nastąpiło nagłe zatrzymanie krążenia lub utrata przytomności, a resuscytacja okazywała się nieskuteczna. W sześciu przyczyną pobudzenia była ostra psychoza, w czterech działanie narkotyków, zazwyczaj w wysokim stężeniu. Tylko w pięciu przypadkach stwierdzono obecność wybroczyn w spojówkach. Najbardziej prawdopodobną przyczyną śmierci było współistnienie nasilonego wysiłku fizycznego spowodowanego patologicznym pobudzeniem psychoruchowym, z przymusowym unieruchomieniem pogarszającym funkcjonowanie układu oddechowego. Mechanizm ten jest określany jako asfiksja restrykcyjna. Restraint asphyxia. An analysis of the circumstances and mechanism of death in agitated, physically restrained individuals Recent years saw frequent media reports of young people who die while they are being arrested by the police. Death in these circumstances affects people who are agitated and restrained with the use of force, with their autopsies indicating no unequivocally traumatic cause of death. The goal of this study was to identify the mechanism and circumstances of sudden deaths in agitated individuals who are being restrained. Ten cases evaluated at our center since 2010 were included in this study: nine involved forensic postmortem examination and one involved casefile analysis. In each case there was sudden cardiac arrest or at least a loss of consciousness, and the cardiopulmonary resuscitation proved ineffective. In six cases the cause of agitation was acute psychosis, in four it was an effect of narcotics, usually in high concentration. Conjunctival petechiae were detected in only five cases. The most probable cause of death in the evaluated cases was the combination of physical exertion caused by pathological psychomotor agitation and forcible restraint, hindering the function of the respiratory system. This mechanism is known as restraint asphyxia.

Acute behavioural disturbance: recognition, assessment and management

Acute behavioural disturbance (ABD) is a clinical emergency which typically affects overweight men in their mid-thirties who chronically misuse illicit stimulants. People with ABD are most likely to be seen in police custody or emergency departments, therefore nurses working in these areas must be able to recognise the signs and symptoms and know how to respond appropriately. Presentation varies, but the signs and symptoms commonly include extreme agitation, hyperthermia, hostility and exceptional strength without fatigue. Further, it is important to recognise that people with ABD are at risk of developing metabolic acidosis, hyperkalaemia, rhabdomyolysis or disseminated intravascular coagulation. This article gives an overview of ABD and describes the main elements of management and treatment.

Methamphetamine deaths: Changing trends and diagnostic issues

The term 'amphetamine' refers to a class of synthetic drugs which includes methamphetamine. The latter is a globally popular drug of abuse which induces euphoria, affecting cognitive/psychomotor performance and sleep. It also provokes risk taking and violent behaviour. The central effects of methamphetamine are due to the overproduction of neurotransmitters, resulting in high levels of dopamine. In recent years, there have been significant increases in cases of methamphetamine abuse in North and South America, Australia and Asia due to its ready availability and low cost. The following review examines changing trends in methamphetamine use and problems that arise diagnostically in medico-legal cases in determining the significance of post-mortem blood levels, the relationship of these to ante-mortem levels, the possible effects on physical and psychological behaviours and the possible contribution of the drug to a lethal episode.

Police Responses to Persons with Mental Illness: The Policy and Procedures Manual of One Australian Police Agency and ‘Procedural Justice Policy’

Persons with mental illness (PWMI) often report negative perceptions of police treatment following receiving criminalising and heavy-handed police responses. To appropriately control officer discretion and to harness ethical, legal, and efficient police practice when encountering vulnerable and diverse individuals, police agencies across the world issue policy documents to their officers. These documents serve as a reflection regarding how police agencies aspire to manage PWMI in the community. Using a procedural justice framework, this research measures how a large police agency in Australia aspires to manage PWMI and whether the police policy document provides sufficient detail in advocating the appropriate and just police treatment of PWMI. A content analysis of the policy document revealed a lack of sufficient procedural guidelines in effectively controlling police officer discretion when encountering PWMI in the community. This article argues that without further consolidation to embed appropriate procedural guidelines into the policy document, the procedural policy gaps may have a negative effect on the experiences of PWMI when encountering the police.

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.

The relationship between positional asphyxia and increasing body mass index

Review of the files of the Pathology section of Forensic Science SA over 17 yrs (January 2003-December 2019) revealed 32 adult cases of positional asphyxia (age range 18-87 years; average 49 years - m:f ratio 3:1). Predisposing/causative conditions were accidents, N = 8, alcohol intoxication N = 7, neurological disease N = 7, drug intoxication N = 5, morbid obesity N = 2, combinations of factors N = 2, and a single homicide N = 1. There was one case with below normal weight (BMI 17.9), with 6 cases having normal weights (BMI range 18.9-24.6, average 22.3), 9 being overweight (BMI range 25.3-29.5, average 27.9), and 16 being obese (BMI range 30-66.2, average 40.9). Only 7 cases (22%) had either under/normal weight compared to 25 (78%) who were overweight/obese (p < 0.05). Increasing body mass appears to be a risk factor to be considered in all forms of positional asphyxia; BMI should, therefore, be routinely taken into account in the forensic evaluation of such cases.