Safety considerations in the epilepsy monitoring unit for psychogenic nonepileptic seizures

Do we intervene less and slower in the epilepsy monitoring unit for psychogenic seizures?

PURPOSE

Individuals with psychogenic non-epileptic seizures (PNES) can be stigmatized in healthcare settings. We aimed to compare intervention rate (IR), intervention time (IT), and adverse event (AE) rate between PNES and epileptic seizures (ES) in the epilepsy monitoring unit (EMU).

METHODS

We used a prospective database of consecutive admissions to our centre's EMU between August 2021 and September 2022. We excluded purely electric seizures and vague, minor spells with no EEG correlate. We therefore only included electroclinical seizures and PNES. We compared the IR, IT, and AE rate between PNES and ES, as diagnosed by an epileptologist during EEG monitoring. We performed the same comparisons between spells occurring in people admitted with a high vs low suspicion of PNES (HSP vs LSP). We also verified if ITs became longer with repeated PNES.

RESULTS

We analyzed 586 spells: 43 PNES vs 543 ES, or 133 HSP vs 453 LSP. Our univariate analyses showed that IR was higher for PNES than for ES (93 % vs 61 %, p <.001) but that IT and AE rate were similar across groups. This higher IR was only apparent outside weekday daytime hours, when EEG technologists were not present. HSP did not differ from LSP in terms of IR, IT, and AE rate. As PNES accumulated in individual patients, IT tended to be longer (Spearman's correlation = 0.42; p =.012).

SIGNIFICANCE

Our EMU staff did not intervene less or slower for PNES. Rather, IR was higher for PNES than for ES, but IT tended to be longer with repeat PNES.

Prevalence of ictal injuries in functional (psychogenic nonepileptic) seizures: A systematic review and meta-analysis

OBJECTIVE

Ictal injuries have long been considered typical signs of epileptic seizures. However, studies have shown that patients with functional seizures (FS)-also named psychogenic nonepileptic seizures-can also present these signs, misleading physicians and delaying a correct diagnosis. This systematic review aimed to assess the prevalence of injuries from FS.

METHODS

A literature search was performed in PubMed, Embase, LILACS (Latin American and Caribbean Health Sciences Literature), Scopus, Web of Science, PsycINFO, Google Scholar, OpenGrey, and ProQuest. Observational studies were included. The risk of bias was assessed using the Joanna Briggs Institute (JBI) checklist for studies reporting prevalence data. RStudio was used for meta-analyses. Cumulative evidence was evaluated according to Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) criteria.

RESULTS

From the 2607 identified records, 41 studies were included in the qualitative synthesis, and 28 were included in meta-analyses. A meta-analysis of 13 studies, including 1673 individuals, resulted in an overall lifetime prevalence of injuries due to FS per person of 25% (95% confidence interval [CI] = 19%-32%, I2  = 88%). Considering a limited period (video-electroencephalographic [VEEG] monitoring days), a meta-analysis of 13 studies, including 848 individuals, resulted in an injury prevalence due to FS per person of .7% (95% CI = 0%-3%, I2  = 73%). Also, a meta-analysis of eight studies, including 1000 individuals, resulted in a prevalence of injuries per FS of .1% (95% CI = 0%-.98%, I2  = 49%). The certainty in cumulative evidence assessed by GRADE was rated "very low" for lifetime prevalence of injuries per person, "low" for prevalence per person during VEEG monitoring, and "moderate" for prevalence per number of FS.

SIGNIFICANCE

Overall pooled lifetime prevalence of injuries due to FS per person was 25%. In comparison, the prevalence of injuries per person during VEEG monitoring and per functional seizure was .7% and .1%, respectively. [Correction added on 07 October 2023, after first online publication: In the preceding sentence, 'consecutively' was corrected to 'respectively'.] The evidence of the occurrence of injuries due to FS breaks the paradigm that epileptic seizures can cause injuries but FS cannot.

Minimum standards for inpatient long-term video-EEG monitoring: A clinical practice guideline of the international league against epilepsy and international federation of clinical neurophysiology

The objective of this clinical practice guideline is to provide recommendations on the indications and minimum standards for inpatient long-term video-electroencephalographic monitoring (LTVEM). The Working Group of the International League Against Epilepsy and the International Federation of Clinical Neurophysiology develop guidelines aligned with the Epilepsy Guidelines Task Force. We reviewed published evidence using The Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) statement. We found limited high-level evidence aimed at specific aspects of diagnosis for LTVEM performed to evaluate patients with seizures and nonepileptic events (see Table S1). For classification of evidence, we used the Clinical Practice Guideline Process Manual of the American Academy of Neurology. We formulated recommendations for the indications, technical requirements, and essential practice elements of LTVEM to derive minimum standards used in the evaluation of patients with suspected epilepsy using GRADE (Grading of Recommendations, Assessment, Development, and Evaluation). Further research is needed to obtain evidence about long-term outcome effects of LTVEM and establish its clinical utility.

Minimum standards for inpatient long-term video-electroencephalographic monitoring: A clinical practice guideline of the International League Against Epilepsy and International Federation of Clinical Neurophysiology

The objective of this clinical practice guideline is to provide recommendations on the indications and minimum standards for inpatient long-term video-electroencephalographic monitoring (LTVEM). The Working Group of the International League Against Epilepsy and the International Federation of Clinical Neurophysiology develop guidelines aligned with the Epilepsy Guidelines Task Force. We reviewed published evidence using the PRISMA (Preferred Reporting Items for Systematic Review and Meta-Analysis) statement. We found limited high-level evidence aimed at specific aspects of diagnosis for LTVEM performed to evaluate patients with seizures and nonepileptic events. For classification of evidence, we used the Clinical Practice Guideline Process Manual of the American Academy of Neurology. We formulated recommendations for the indications, technical requirements, and essential practice elements of LTVEM to derive minimum standards used in the evaluation of patients with suspected epilepsy using GRADE (Grading of Recommendations Assessment, Development, and Evaluation). Further research is needed to obtain evidence about long-term outcome effects of LTVEM and to establish its clinical utility.

Intervention Time and Adverse Events in a Canadian Epilepsy Monitoring Unit

BACKGROUND

Intervention time (IT) in response to seizures and adverse events (AEs) have emerged as key elements in epilepsy monitoring unit (EMU) management. We performed an audit of our EMU, focusing on IT and AEs.

METHODS

We performed a retrospective study on all clinical seizures of admissions over a 1-year period at our Canadian academic tertiary care center's EMU. This EMU was divided in two subunits: a daytime three-bed epilepsy department subunit (EDU) supervised by EEG technicians and a three-bed neurology ward subunit (NWU) equipped with video-EEG where patients were transferred to for nights and weekends, under nursing supervision. Among 124 admissions, 58 were analyzed. A total of 1293 seizures were reviewed to determine intervention occurrence, IT, and AE occurrence. Seizures occurring when the staff was present at bedside at seizure onset were analyzed separately.

RESULTS

Median IT was 21.0 (11.0-40.8) s. The EDU, bilateral tonic-clonic seizures (BTCS), and the presence of a warning signal were associated with increased odds of an intervention taking place. The NWU, BTCS, and seizure rank (seizures were chronologically ordered by the patient for each subunit) were associated with longer ITs. Bedside staff presence rate was higher in the EDU than in the NWU (p < 0.001). AEs occurred in 19% of admissions, with no difference between subunits. AEs were more frequent in BTCS than in other seizure types (p = 0.001).

CONCLUSION

This study suggests that close monitoring by trained staff members dedicated to EMU patients is key to optimize safety. AE rate was high, warranting corrective measures.

Suggestive seizure induction for inpatients with suspected psychogenic nonepileptic seizures

OBJECTIVE

To determine the utility of suggestive seizure induction for inpatient work-up of suspected psychogenic nonepileptic seizures (PNES).

METHODS

Prospective study of epilepsy center inpatient admissions with suspected PNES. Patients were randomized to undergo suggestive induction first (group A) and then, if necessary, long-term video-electroencephalography (EEG) monitoring, or vice versa (group B). Diagnostic pathways were compared. Potential clinical predictors for diagnostic success were evaluated.

RESULTS

Length of in-hospital stay did not significantly differ between groups. Suspicion of PNES was confirmed in 43 of 77 (56%) patients, evenly distributed between group A (22 of 39) and group B (21 of 38). In nine patients, recorded habitual seizures were epileptic and in 25 cases, no diagnostic event could be recorded. Diagnosis of PNES was ascertained primarily by recording a typical seizure through suggestive induction in 24 patients and through long-term monitoring in 19 patients. In group A (induction first), monitoring was not deemed necessary in 21% of cases. In group B (monitoring first), 13% would have remained inconclusive without suggestive induction. Patients who reported triggers to their habitual seizures were not more likely to have spontaneous or provoked PNES during monitoring or suggestive inducion, respectively. Patients with subjective seizure prodromes (auras) were significantly more likely to have a PNES during suggestive induction than those without (odds ratio [OR] 3.4, 95% confidence interval [CI] 1.1-10.4). There was no significant difference in seizure frequency between patients with spontaneous PNES during long-term monitoring and those with nondiagnostic monitoring sessions.

SIGNIFICANCE

Our results support the notion that suggestive seizure induction can reduce the number of inconclusive inpatient workups, and can obviate resource-intensive long-term monitoring in one fifth of cases. Patients who are aware of prodromes might have a higher chance of having seizures induced through suggestion.

SUDEP in patients with epilepsy and nonepileptic seizures

We report 13 SUDEP cases in the North American SUDEP Registry with both psychogenic nonepileptic seizures (PNES) and epileptic seizures (ES) among a consecutive series of 231 cases (excluding epileptic encephalopathies). On average, cases of PNES + ES died at a younger age (23 ± 11 years) than the ES-only cohort (30 ± 14 years), and died an average of 3 years after PNES diagnosis. We found no statistically significant confounding cardiac, respiratory, or psychiatric comorbidities and equal rates of anti-seizure medication adherence, although there was a trend for higher rates of psychiatric disorders in the PNES group. Our findings confirm that patients with comorbid ES and PNES can die from SUDEP and that there may be a high-risk period after the diagnosis of PNES is made in patients with comorbid ES. Such patients should be closely monitored and provided with coordinated care of both their epilepsy and psychiatric disorder(s).

Association between epilepsy and oral maxillofacial trauma: A systematic review and meta-analysis

A systematic literature search was conducted (through April 2017), using Web of Science, PubMed and Virtual Health Library, manual reference list, and grey literature searches. The quality of the studies was evaluated using the Newcastle-Ottawa Quality Assessment Scale. The meta-analysis was performed using R software. A total of 30 studies was included in this review. From a total of 25 studies included in the meta-analysis, the prevalence of oral and maxillofacial injuries among epileptic subjects was 19%. Among the epileptic patients who suffered some type of injury due to epileptic seizures, 52% had facial soft tissue injuries (95%CI: 28-75%), 18% suffered dental trauma (95%CI: 11-29%), and 12% (95%CI: 4-28%) suffered maxillofacial fractures. Epileptic patients were more likely to have oral and maxillofacial injuries than healthy individuals (OR: 5.22, 95%CI: 2.84-9.36) and subjects with psychogenic nonepileptic seizures (OR: 2.77, 95%CI: 1.28-5.99), but not than patients with special needs (OR: 2.45,95%CI: 0.95-6.31).

Time to response and patient visibility during tonic-clonic seizures in the epilepsy monitoring unit

OBJECTIVE

There is a high cost associated with recording quality video and electroencephalography (EEG) data in National Association of Epilepsy Center (NAEC) level IV epilepsy monitoring units (EMU). This study considers potential quality measures in EMUs for generalized tonic-clonic (GTC) seizures: types of safety signals, response time, and visibility of patient's limbs for semiology. These quality measures have been summarized across 12 EMUs to estimate response times to GTC seizures and the quality of video data that is captured during admissions.

METHODS

Video electroencephalographies (vEEGs) from two prospective regulatory studies for the Brain Sentinel device were reviewed. A total of 232 subjects with a history of GTC seizures underwent routine clinical EMU stays. Fifty-four of the study subjects had 96 GTC seizures. The vEEG of events were reviewed for safety signal used, response time, and visibility of patient's limbs.

RESULTS

The average response time from members of the hospital team was 22 s from electrographic generalization (minimum -37 s, maximum 111 s, two no response). For caregivers, average response was 11 s (minimum -15 s, maximum 33 s, 45 not present/no response). In 73% of events, the patient visibility was limited at seizure onset. In 55% of events with limited limb visibility, the visibility was improved (by removing sheets or improving camera angle) >30 s after start of the event. The primary safety signals were as follows: an alert from outside the patient room (54%), button press (23%), hospital team present at seizure start (14%), caregiver vocal alert (6%), and no response (2%).

SIGNIFICANCE

The average response time of caregivers was twice as fast as the hospital team, underscoring the importance of having a person in the room during onset of a GTC seizure. Diagnostic yield could be improved with more timely removal of patient coverings. It was observed that when patients experienced a GTC seizure, 40% were fully or partially obscured for more than 30 s during the event, compromising the ability of epileptologists to evaluate semiology during seizure onset. Automated seizure alarms may help staff get to patients more quickly and improve diagnostic characterization.

Optimising the use of EEG in non-epileptic attack disorder: Results of a UK national service evaluation

PURPOSE

To produce an evidence base to formulate guidelines for optimal performance of EEG in patients referred with a possible diagnosis of non-epileptic attack disorder (NEAD).

METHODS

51 UK EEG departments participated in the prospective study. A pro-forma was completed for all consecutive patients aged 5 years and over referred for EEG over a six month period. Information obtained included referral diagnosis, occurrence/type of attack during EEG, the use of suggestion, length of recording and who was present during the EEG.

RESULTS

11,298 patients were entered into the study. 376 psychogenic non-epileptic seizures (PNES) occurred of which 337 were considered to be of the habitual type. In those patients suspected of having NEAD prior to referral, the use of verbal suggestion increased the yield of habitual attacks by a factor of three in both adults and children. Using suggestive techniques twice, improved the yield further. Non-habitual attacks occurred equally whether or not suggestion was used. At least 90% of habitual PNES occurred within the first 30 min of recording even in those patients having prolonged EEGs. In EEGs where additional professional personnel were present, PNES occurred more frequently.

CONCLUSION

This large multicentre study provides evidence to inform recommendations for EEG to investigate NEAD. We recommend the use of verbal suggestion at least twice and where practical the presence of additional professional staff. A thirty minute recording is sufficient to record a habitual PNES in most instances.

[Diagnosis of non-epileptic paroxysmal disorders and epileptic seizures]

Non-epileptic paroxysmal disorders may clinically manifest in a similar way to epileptic seizures and have to be considered in the differential diagnosis of epilepsy. Syncope, non-epileptic psychogenic seizures, paroxysmal movement disorders, migraine, transient ischemic attacks and parasomnia constitute the major differential diagnoses. A meticulous history and a third party description are useful for the differential diagnosis. Neurological, psychiatric and cardiological examinations are required for the correct differential diagnosis. The interictal electroencephalogram (EEG), which is normal in non-epileptic patients, is frequently normal in epileptic patients at the onset of seizures, but reaches a high sensitivity after repeated recordings. In equivocal cases EEG video monitoring and in the case of suspected cardiac asystole, event recorders are useful diagnostic tools.

Epilepsy monitoring - The patients' views: A qualitative study based on Kolcaba's Comfort Theory

PURPOSE

The aim of this qualitative study was to determine which perception of personal comfort patients name in the context of their hospitalization in an Austrian Epilepsy Monitoring Unit (EMU).

METHODS

Problem-centred interviews with twelve inpatients were conducted. Data analyses were done according to Mayring's qualitative content analyses following the technique of structuring-deductive category assignment.

RESULTS

Patients experienced different kinds of comfort along with their hospitalization in the EMU. Comfort-decreasing factors were bed rest, boredom, and waiting for possible seizures. As comfort-increasing factors, hope for enhanced seizure control, support by family and staff, and intelligible information about the necessity of restrictive conditions were identified.

CONCLUSIONS

The study results should assist health care professionals, enabling them to design comfort enhancing interventions for patients undergoing video-electroencephalography (EEG) investigations in an EMU. Some of these seem to be simple and obtainable without high financial or technical effort. Others are more complex and have to be further assessed for their feasibility.

Neurophysiological investigations for the diagnosis of non-epileptic attack disorder in neuropsychiatry services: from safety standards to improved effectiveness

OBJECTIVE

The discipline of clinical neuropsychiatry currently provides specialised services for a number of conditions that cross the traditional boundaries of neurology and psychiatry, including non-epileptic attack disorder. Neurophysiological investigations have an important role within neuropsychiatry services, with video-electroencephalography (EEG) telemetry being the gold standard investigation for the differential diagnosis between epileptic seizures and non-epileptic attacks. This article reviews existing evidence on best practices for neurophysiology investigations, with focus on safety measures for video-EEG telemetry.

METHODS

We conducted a systematic literature review using the PubMed database in order to identify the scientific literature on the best practices when using neurophysiological investigations in patients with suspected epileptic seizures or non-epileptic attacks.

RESULTS

Specific measures need to be implemented for video-EEG telemetry to be safely and effectively carried out by neuropsychiatry services. A confirmed diagnosis of non-epileptic attack disorder following video-EEG telemetry carried out within neuropsychiatry units has the inherent advantage of allowing diagnosis communication and implementation of treatment strategies in a timely fashion, potentially improving clinical outcomes and cost-effectiveness significantly.

CONCLUSION

The identified recommendations set the stage for the development of standardised guidelines to enable neuropsychiatry services to implement streamlined and evidence-based care pathways.

Can an exercise bicycle be safely used in the epilepsy monitoring unit?: An exercise method to provoke epileptic seizures and the related safety issues

BACKGROUND AND PURPOSE

Long-term videoelectroencephalogram (video-EEG) monitoring is performed to diagnose an epileptic seizure and to investigate the differential diagnosis of paroxysmal events. To provoke an epileptic seizure, an exercise method is performed in some cases during long-term video-EEG recording in the epilepsy monitoring unit (EMU). The purpose of this study was two-fold: to assess the frequency and severity of adverse events associated with the use of an exercise bicycle and to find a way to safely use it in the EMU.

METHODS

A retrospective survey was performed on all epileptic seizure videos recorded in the EMU from January 2012 to December 2013. Three hundred and fifty patients were included in this study.

RESULTS

Eleven patients experienced an epileptic seizure while riding the exercise bicycle in the EMU. One patient's foot got stuck between the cycling pedal and its strap, and one patient fell off the exercise bicycle during the epileptic seizure. However, there were no serious adverse events over two years.

CONCLUSION

Epileptic seizures were not frequent while riding the exercise bicycle, and serious injuries did not occur. But, there is a need to improve the safety in the EMU to control the potentially dangerous factors associated with the use of the exercise bicycle and to continuously monitor the patients with help from the staff.

New insights into psychogenic nonepileptic seizures 2011-2014

PURPOSE

There has been a rapid increase in the rate of publications about psychogenic nonepileptic seizures (PNES). This review summarises insights from the 50 most important original articles about PNES published since 2011 and describes the advances made in the understanding of PNES over the last 3 years.

METHOD

We carried out a systematic literature search of all English language publications about PNES published between October 2011 and October 2014 on Scopus, Ovid Medline and Web of Knowledge, and inspected all abstracts. Having excluded all review articles, case reports, conference abstracts, articles exploring PNES in children, and articles not actually focussing on PNES, we considered 150 papers for inclusion in this review. We assessed the quality of the identified studies and used expert judgement to identify the 50 most important publications from the review period and composed a narrative review based on these original papers.

RESULTS

Almost one half of the studies initially identified only provided Class 4 evidence. Recent work has provided more support for a biopsychosocial account of PNES. It has illustrated the heterogeneity of PNES, identifying varying and distinct psychological profiles of individuals with this disorder. These findings suggest that intervention needs to be flexible or adaptive if it is appropriately to target the different mechanisms which may give rise to PNES. Several educational and psychotherapeutic interventions for PNES have been described, but sufficiently powered randomised controlled trials are yet to be undertaken. Recent research using social, economic and quality of life indicators has provided further evidence of the societal and individual burden of PNES.

CONCLUSION

The research into PNES published over the last 3 years has deepened our understanding of the condition as a biopsychosocial disorder which is neither a "physical" nor a "psychological" condition. A number of small studies have demonstrated the potential of educational and psychotherapeutic treatments, but rigorous and sufficiently large trials still need to be conducted to determine the effectiveness of these interventions.

A European survey on current practices in epilepsy monitoring units and implications for patients' safety

OBJECTIVE

This study aimed to survey current practices in European epilepsy monitoring units (EMUs) with emphasis on safety issues.

METHODS

A 37-item questionnaire investigating characteristics and organization of EMUs, including measures for prevention and management of seizure-related serious adverse events (SAEs), was distributed to all identified European EMUs plus one located in Israel (N=150).

RESULTS

Forty-eight (32%) EMUs, located in 18 countries, completed the questionnaire. Epilepsy monitoring unit beds are 1-2 in 43%, 3-4 in 34%, and 5-6 in 19% of EMUs; staff physicians are 1-2 in 32%, 3-4 in 34%, and 5-6 in 19% of EMUs. Personnel operating in EMUs include epileptologists (in 69% of EMUs), clinical neurophysiologists trained in epilepsy (in 46% of EMUs), child neurologists (in 35% of EMUs), neurology and clinical neurophysiology residents (in 46% and in 8% of EMUs, respectively), and neurologists not trained in epilepsy (in 27% of EMUs). In 20% of EMUs, patients' observation is only intermittent or during the daytime and primarily carried out by neurophysiology technicians and/or nurses (in 71% of EMUs) or by patients' relatives (in 40% of EMUs). Automatic detection systems for seizures are used in 15%, for body movements in 8%, for oxygen desaturation in 33%, and for ECG abnormalities in 17% of EMUs. Protocols for management of acute seizures are lacking in 27%, of status epilepticus in 21%, and of postictal psychoses in 87% of EMUs. Injury prevention consists of bed protections in 96% of EMUs, whereas antisuffocation pillows are employed in 21%, and environmental protections in monitoring rooms and in bathrooms are implemented in 38% and in 25% of EMUs, respectively. The most common SAEs were status epilepticus reported by 79%, injuries by 73%, and postictal psychoses by 67% of EMUs.

CONCLUSIONS

All EMUs have faced different types of SAEs. Wide variation in practice patterns and lack of protocols and of precautions to ensure patients' safety might promote the occurrence and severity of SAEs. Our findings highlight the need for standardized and shared protocols for an effective and safe management of patients in EMUs.

A clinically oriented perspective on psychogenic nonepileptic seizure-related emergencies

Psychogenic nonepileptic seizures (PNES) can present emergently and are often mistaken for epileptic seizures. PNES emergencies have not been well studied, and yet there are associated serious morbidities, particularly when patients are seen in an emergency setting and are misdiagnosed. PNES may be prolonged, mimicking status epilepticus, a condition we refer to as nonepileptic psychogenic status (NEPS), and patients may receive aggressive and unnecessary medical treatments that can lead to serious iatrogenic complications, including death. NEPS is also associated with an increased risk of self-harm, including suicide attempts, and may indicate a serious comorbid psychiatric illness. In addition to iatrogenic complications of PNES, accidents and injuries are an underrecognized source of morbidity. PNES may also present during medical procedures, which may not only interfere with their completion, but may alarm practitioners who, fearing liability, may initiate further medical evaluations and treatments. When PNES occur during pregnancy, patients may be misdiagnosed with eclampsia and their offspring delivered prematurely. They also risk being placed on medications that are harmful to the fetus. Increased awareness of PNES is necessary to prevent iatrogenic harm and to identify underlying psychiatric illnesses that carry their own risks. As yet, data available to guide treatment are scant, and further study is needed.

Patients' safety in the epilepsy monitoring unit: time for revising practices

PURPOSE OF REVIEW

Long-term video-electroencephalography monitoring (LTM) in epilepsy monitoring units (EMUs) exposes patients to a variety of serious adverse events (SAEs) and safety issues, which have recently caught attention and are summarized in this review.

RECENT FINDINGS

SAEs observed during LTM affect about 10% of patients and include secondary generalized tonic-clonic seizures, seizure clusters and status epilepticus, unusual for the patient; seizure-related falls, injuries, fractures, and aspiration; postictal psychosis; and cardiorespiratory distress, including sudden unexpected death in epilepsy (SUDEP) and near-SUDEP, which were encountered by more than 10% of European and Australian EMUs. Accordingly, 3% of US-based EMUs suffer a death within a 1-year duration census. Many of these SAEs might be promoted by antiepileptic drugs (AEDs) withdrawal, for which no specific guideline is currently available. Current recommendations regarding optimal organization of EMUs, and in particular continuous supervision by a dedicated staff, are not followed by respectively 20 and 26% of European and US-based EMUs.

SUMMARY

SAEs during LTM are a significant concern and might be aggravated by suboptimal EMU organization and staff education. Lack of high-level evidence stands out as the main limiting factor to the development and dissemination of appropriate guidelines.