Coma of unknown origin in the emergency department: implementation of an in-house management routine

Etiologies and factors associated with mortality in patients with non-traumatic coma in a tertiary hospital in Bukavu, eastern Democratic Republic of the Congo

Non-traumatic coma (NTC) is a common medical condition often associated with poor outcomes. Identifying underlying causes is crucial for effective management and prognostication, particularly in resource-poor settings. This study aimed to identify the most common causes and prognostic factors of NTC in a tertiary hospital in Bukavu, in the eastern Democratic Republic of the Congo (DRC), using the Glasgow Coma Scale (GCS) as well as other simple and affordable clinical and paraclinical tools. This retrospective observational study included 219 consecutive patients admitted to the intensive care unit of the Provincial General Hospital of Bukavu between January 2016 and December 2018. Sociodemographic, clinical, and laboratory data were also collected. Bivariate and multivariate analyses were performed to identify different causes and factors associated with poor outcomes in these patients. The median age of the patients was 49 (interquartile range [IQR]: 33-61) years, and they were predominantly men (62.8%). The most common causes of NTC were stroke (25.7%), acute metabolic complications of diabetes (21.9%), and primary brain infections (meningoencephalitis, 16.0%; and cerebral malaria, 14.2%). The NTC-related in-hospital mortality rate was 35.2%. A high mortality was significantly and independently associated with a GCS<7 (adjusted odds ratio [OR]: 4.30, 95% confidence interval [CI]: 1.73-10.71), the presence of meningismus at clinical evaluation (adjusted odds ratio [aOR] 3.86, 95%CI: 1.41-10.55), oxygen saturation <90% (aOR 3.99, 95%CI: 1.71-9.28), the consumption of traditional herbal medicines prior to hospital admission (aOR 2.82, 95%CI: 1.16-6.86), and elevated serum creatinine (aOR 1.64, 95%CI: 1.17-2.29). In conclusion, clinical neurological examinations, along with simple and affordable paraclinical investigations, can provide sufficient information to determine the etiology of NTC and evaluate the prognosis of comatose patients, even in resource-poor settings. Physicians may use the GCS as a simple, reliable, and affordable tool to identify patients who require special attention and care.

Survey study of the etiology of non-traumatic altered consciousness in the Emergency Department at Suez Canal University Hospital in Egypt

BACKGROUND

Disorders of consciousness including coma in non-trauma patients can be caused by a wide variety of pathologies affecting the central nervous system. They represent a frequent challenge in emergency medicine and are combined with a very high in-hospital mortality. Hence, early treatment of these patients is vital and increases the likelihood of a good outcome.

AIM

To identify the causes of altered consciousness presentation to the Emergency Department at Suez Canal University Hospital.

METHODS

This was a descriptive cross-sectional study conducted on 87 patients with acute non-traumatic disturbed level of consciousness (DLOC) at the Emergency Department.

RESULTS

The mean age of the studied patients was 60.5 ± 13.6 years. Among them, 60% were males and 40% were females. The most common cause of acute non-traumatic DLOC was systemic infection, such as sepsis and septic shock (25.3%), followed by respiratory causes (24.1%) and neurological causes (18.4%).

CONCLUSION

The most common cause of acute non-traumatic DLOC was systemic infections followed by respiratory and neurological causes.

The diagnostic value of the neurological examination in coma of unknown etiology

Background

Identifying the cause of non-traumatic coma in the emergency department is challenging. The clinical neurological examination is the most readily available tool to detect focal neurological deficits as indicators for cerebral causes of coma. Previously proposed clinical pathways have granted the interpretation of clinical findings a pivotal role in the diagnostic work-up. We aimed to identify the actual diagnostic reliability of the neurological examination with regard to identifying acute brain damage.

Methods

Eight hundred and fifty-three patients with coma of unknown etiology (CUE) were examined neurologically in the emergency department following a predefined routine. Coma-explaining pathologies were identified retrospectively and grouped into primary brain pathology with proof of acute brain damage and other causes without proof of acute structural pathology. Sensitivity, specificity and percentage of correct predictions of different examination protocols were calculated using contingency tables and binary logistic regression models.

Results

The full neurological examination was 74% sensitive and 60% specific to detect acute structural brain damage underlying CUE. Sensitivity and specificity were higher in non-sedated patients (87/61%) compared to sedated patients (64%/59%). A shortened four-item examination protocol focusing on pupils, gaze and pyramidal tract signs was only slightly less sensitive (67%) and more specific (65%).

Conclusions

Due to limited diagnostic reliability of the physical examination, the absence of focal neurological signs in acutely comatose patients should not defer from a complete work-up including brain imaging. In an emergency, a concise neurological examination should thus serve as one part of a multimodal diagnostic approach to CUE.

Can emergency department clinicians diagnose gamma-hydroxybutyrate (GHB) intoxication based on clinical observations alone?

OBJECTIVES

Gamma-hydroxybutyrate (GHB) is a drug of abuse with central depressing effects, which may cause coma with a GCS score as low as 3. A rapid diagnosis 'GHB intoxication' may prevent unnecessary diagnostic work-up and may lead to guided, less invasive, treatment. The aim of this study was to evaluate if ED physicians' clinical evaluation were sufficient for diagnosis in patients with suspected GHB-intoxication.

METHODS

Patients presenting at the ED with a GCS<15 and a potential intoxication with drugs of abuse for whom urine toxicology screen was performed were included consecutively. After a first assessment, the ED physician registered the most likely initial diagnosis in the hospital information system. Urine of these patients was tested with a validated gas chromatography analytical method for GHB (confirmation test). The initial diagnoses were compared for agreement with the results of the confirmation test.

RESULTS

A total of 506 patients were included, 100 patients tested positive for GHB and 406 patients tested negative for GHB. Sensitivity and specificity of the ED physicians compared with the confirmation test to diagnose GHB intoxications were 63% (95% CI 52 to 73) and 93% (95% CI 90 to 95), respectively. The positive predictive value was 67% (95% CI 60 to 77) and the negative predictive value was 92% (95% CI 88 to 94).

CONCLUSION

Physicians underestimate the presence of GHB intoxication and can fail to diagnose GHB intoxication based on clinical observations alone. In the future, a rapid reliable initial analytical GHB test in addition to clinical judgement could be valuable to reduce false negative diagnosis.

[Nontraumatic resuscitation room management of critically ill patients]

Kritisch kranke Patienten werden regelmäßig in der prähospitalen Notfallmedizin versorgt. Gerade an der Nahtstelle zwischen prähospitaler und innerklinischer Versorgung besteht eine große Herausforderung darin, die Patientenbehandlung ohne Zeitverlust und auf hohem Niveau fortzuführen. Hierzu gehören die Stabilisierung der Vitalfunktionen (inkl. Atemwegsicherung, nichtinvasive/invasive Beatmung, Kreislaufstabilisierung) und Umsetzung einer geeigneten Diagnostik- und Therapiestrategie (inkl. Laboruntersuchungen, Sonographie, radiologischer Bildgebung). In den letzten Jahren hat sich daher ein Interessens- und Forschungsschwerpunkt zum Thema „nichttraumatologische Schockraumversorgung“ entwickelt. Mittlerweile liegen erste monozentrische Daten vor und es wird kontinuierlich an der Entwicklung eines nichttraumatologischen Schockraummanagements zur optimalen Versorgung von kritisch kranken Patienten in der zentralen Notaufnahme gearbeitet. Der vorliegende Beitrag beschreibt auf der Basis von ersten Studien, Erfahrungen und Expertenmeinungen eine strukturierte Vorgehensweise im nichttraumatologischen Schockraummanagement.

The accuracy of initial diagnoses in coma: an observational study in 835 patients with non-traumatic disorder of consciousness

BACKGROUND

Management of patients with coma of unknown etiology (CUE) is a major challenge in most emergency departments (EDs). CUE is associated with a high mortality and a wide variety of pathologies that require differential therapies. A suspected diagnosis issued by pre-hospital emergency care providers often drives the first approach to these patients. We aim to determine the accuracy and value of the initial diagnostic hypothesis in patients with CUE.

METHODS

Consecutive ED patients presenting with CUE were prospectively enrolled. We obtained the suspected diagnoses or working hypotheses from standardized reports given by prehospital emergency care providers, both paramedics and emergency physicians. Suspected and final diagnoses were classified into I) acute primary brain lesions, II) primary brain pathologies without acute lesions and III) pathologies that affected the brain secondarily. We compared suspected and final diagnosis with percent agreement and Cohen's Kappa including sub-group analyses for paramedics and physicians. Furthermore, we tested the value of suspected and final diagnoses as predictors for mortality with binary logistic regression models.

RESULTS

Overall, suspected and final diagnoses matched in 62% of 835 enrolled patients. Cohen's Kappa showed a value of κ = .415 (95% CI .361-.469, p < .005). There was no relevant difference in diagnostic accuracy between paramedics and physicians. Suspected diagnoses did not significantly interact with in-hospital mortality (e.g., suspected class I: OR .982, 95% CI .518-1.836) while final diagnoses interacted strongly (e.g., final class I: OR 5.425, 95% CI 3.409-8.633).

CONCLUSION

In cases of CUE, the suspected diagnosis is unreliable, regardless of different pre-hospital care providers' qualifications. It is not an appropriate decision-making tool as it neither sufficiently predicts the final diagnosis nor detects the especially critical comatose patient. To avoid the risk of mistriage and unnecessarily delayed therapy, we advocate for a standardized diagnostic work-up for all CUE patients that should be triggered by the emergency symptom alone and not by any suspected diagnosis.

Quantitative Infrared Pupillometry in Nonconvulsive Status Epilepticus

BACKGROUND

Nonconvulsive status epilepticus (NCSE) is a frequent disorder in neurocritical care and diagnosing it can be challenging. NCSE patients often show altered pupil function, but nature and extent may vary. Infrared pupillometry allows detection of subtle changes of pupil function. The neurological pupil index (NPi) is considered a surrogate marker of global pupil function which is supposed to be independent of absolute parameters such as the pupil diameter.

OBJECTIVE

Cross-sectional observational study to assess whether NPi is altered in NCSE.

METHODS

128 consecutive adult emergency patients who had experienced a suspected seizure, have not reached their prior functional level regarding level of consciousness, mental status or focal deficits, had no obvious clinical signs of status epilepticus and had an EEG indication as determined by the treating clinician for exclusion of NCSE were examined by routine EEG and pupillometry. Exclusion criteria were ocular comorbidity (n = 21) and poor EEG quality (n = 4). Pupillometry was performed once directly before the beginning of EEG recording. NCSE diagnosis (no NCSE, possible NCSE and confirmed NCSE) was established according to Salzburg consensus criteria blinded to pupillometry results. Group comparison was performed for right NPi, left NPi, lowest NPi of both sides (minNPi) and the absolute difference of both sides (diffNPi) applying non-parametric testing. In post-hoc analysis, receiver operating characteristics (ROC) of NCSE diagnosis (combined confirmed NCSE and possible NCSE) were performed for minNPi and diffNPi.

RESULTS

From 103 patients included in the final analysis, 5 (4.9%) had confirmed NCSE, 7 (6.8%) had possible NCSE. Right NPi (p = 0.002), left NPi (p < 0.001) and minNPi (p < 0.001) were significantly lower in "confirmed NCSE" and "possible NCSE" compared to "no NCSE"; diffNPi was significantly higher in "confirmed NCSE" and "possible NCSE" compared to "no NCSE" (p < 0.001). There was no significant difference of minNPi and diffNPi between "confirmed NCSE" and "possible NCSE". ROC analysis showed an optimal cut-off of minNPi for NCSE diagnosis of 4.0 (AUC = 0.93, 95% CI 0.86-0.99). Optimal ROC analysis cut-off of diffNPi for NCSE diagnosis was 0.2 (AUC = 0.89, 95% CI 0.80-0.99).

CONCLUSIONS

NPi was significantly reduced and the difference between left and right NPi was significantly higher in confirmed NCSE. An NPi < 4.0 on either side as well as an NPi difference of both sides > 0.2 may be potential indicators of NCSE. Infrared pupillometry may be a helpful diagnostic tool in the assessment of NCSE and should be studied further in larger populations.

Der Schockraum als Nahtstelle zwischen Präklinik und Klinik

Die ständige Vorhaltung und Verfügbarkeit eines Schockraums zur Versorgung von kritisch kranken und schwer verletzten Patienten ist eine wesentliche und für die transsektorale Notfallversorgung wichtige klinische Ressource. In diesem Artikel sollen die derzeitigen Entwicklungen der Schockraumbereitstellung in Deutschland aufgezeigt werden.

Acute neurological care in north-east Germany with telemedicine support (ANNOTeM): protocol of a multi-center, controlled, open-label, two-arm intervention study

Background

Both diagnosis and treatment of neurological emergencies require neurological expertise and are time-sensitive. The lack of fast neurological expertise in regions with underserved infrastructure poses a major barrier for state-of-the-art care of patients with acute neurological diseases and leads to disparity in provision of health care. The main purpose of ANNOTeM (acute neurological care in North East Germany with telemedicine support) is to establish effective and sustainable support structures for evidence based treatments for stroke and other neurological emergencies and to improve outcome for acute neurological diseases in these rural regions.

Methods

A “hub-and-spoke” network structure was implemented connecting three academic neurological centres (“hubs”) and rural hospitals (“spokes”) caring for neurological emergencies. The network structure includes (1) the establishment of a 24/7 telemedicine consultation service, (2) the implementation of standardized operating procedures (SOPs) in the network hospitals, (3) a multiprofessional training scheme, and (4) a quality management program. Data from three major health insurance companies as well as data from the quality management program are being collected and evaluated. Primary outcome is the composite of first time of receiving paid outpatient nursing care, first time of receiving care in a nursing home, or death within 90 days after hospital admission.

Discussion

Beyond stroke only few studies have assessed the effects of telemedically supported networks on diagnosis and outcome of neurological emergencies. ANNOTeM will provide information whether this approach leads to improved outcome. In addition, a health economic analysis will be performed.

Study registration

German Clinical Trials Register DRKS00013067, date of registration: November 16 th, 2017, URL: http://www.drks.de/DRKS00013068

Sudden unresponsive patient with normal vital signs: what is going on?

PURPOSE OF REVIEW

To summarize the differential diagnosis and diagnostic approach of sudden unresponsiveness with normal vital signs in various settings, including the ICU.

RECENT FINDINGS

Sudden unresponsiveness may be either transient or persistent, and may result from primary brain diseases or nonstructural systemic conditions. Life-threatening causes should always be discriminated from those more benign. Regional epidemiology, for example regarding intoxications, and evolving therapeutic management, for example for ischemic stroke, should always be taken into account for optimal opportunity for rapid diagnosis and best management.

SUMMARY

Sudden unresponsiveness with normal vital signs should trigger immediate and focused diagnostic evaluation to find or exclude those conditions requiring urgent, and possibly life-saving, management.

Causes of brain dysfunction in acute coma: a cohort study of 1027 patients in the emergency department

Background

Coma of unknown etiology (CUE) is a major challenge in emergency medicine. CUE is caused by a wide variety of pathologies that require immediate and targeted treatment. However, there is little empirical data guiding rational and efficient management of CUE. We present a detailed investigation on the causes of CUE in patients presenting to the ED of a university hospital.

Methods

One thousand twenty-seven consecutive ED patients with CUE were enrolled. Applying a retrospective observational study design, we analyzed all clinical, laboratory and imaging findings resulting from a standardized emergency work-up of each patient. Following a predefined protocol, we identified main and accessory coma-explaining pathologies and related these with (i.a.) GCS and in-hospital mortality.

Results

On admission, 854 of the 1027 patients presented with persistent CUE. Their main diagnoses were classified into acute primary brain lesions (39%), primary brain pathologies without acute lesions (25%) and pathologies that affected the brain secondarily (36%). In-hospital mortality associated with persistent CUE amounted to 25%. 33% of patients with persistent CUE presented with more than one coma-explaining pathology. In 173 of the 1027 patients, CUE had already resolved on admission. However, these patients showed a spectrum of main diagnoses similar to persistent CUE and a significant in-hospital mortality of 5%.

Conclusion

The data from our cohort show that the spectrum of conditions underlying CUE is broad and may include a surprisingly high number of coincidences of multiple coma-explaining pathologies. This finding has not been reported so far. Thus, significant pathologies may be masked by initial findings and only appear at the end of the diagnostic work-up. Furthermore, even transient CUE showed a significant mortality, thus rendering GCS cutoffs for selection of high- and low-risk patients questionable. Taken together, our data advocate for a standardized diagnostic work-up that should be triggered by the emergency symptom CUE and not by any suspected diagnosis. This standardized routine should always be completed - even when initial coma-explaining diagnoses may seem evident.

[Coma in the emergency room]

Coma of unknown origin (CUO) is a frequent unspecific emergency symptom associated with a high mortality. A fast diagnostic work-up is essential given the wide spectrum of underlying diagnoses that are made up of approximately 50% primary central nervous system (CNS) pathologies and approximately 50% extracerebral, almost exclusively internal medical causes. Despite the high mortality associated with this symptom, there are currently no generally accepted management guidelines for adult patients presenting with CUO. We propose an interdisciplinary standard operating procedure (SOP) for patients with acute CUO as has been established in our maximum care hospital. The SOP is triggered by simple triage criteria that are sufficient to identify CUO patients before arrival in hospital. The in-hospital response team is led by a neurologist. Collaboration with nursing staff, internal medicine, anesthesiology, neurosurgery and trauma surgery is organized along structured pathways that include standardized laboratory tests, including cerebrospinal fluid (CSF), toxicology, computed tomography (CT) and CT angiography imaging (CTA). Our data suggest that neurologists and internists need to be placed at the beginning of the diagnostic work-up. Imaging should not just be carried out depending on the clinical syndrome because sensitivity, specificity and inter-rater reliability of the latter are not sufficient and because in many cases, multiple pathologies can be detected that could each explain CUO alone. Clinical examination, imaging and laboratory testing should be regarded as components of an integrative diagnostic approach and the final aetiological classification should only be made after the diagnostic work-up is complete.

A systematic approach to the unconscious patient

Unconscious patients are commonly seen by physicians. They are challenging to manage and in a time sensitive condition, a systematic, team approach is required. Early physiological stability and diagnosis are necessary to optimise outcome. This article focuses on unconscious patients where the initial cause appears to be non-traumatic and provides a practical guide for their immediate care.

Unknown Patients and Neurology Casualty Services in an Indian Metropolitan City: A Decades Experience

OBJECTIVES

A large number of unknown patients without any personal, family, or other identification details represent a unique problem in the neurological emergency services of developing countries like India in a context of legal, humanitarian, and treatment issues. These patients pose a diagnostic and management challenge to treating physicians and staff. There are sparse data on these patients. The objective of this study was to know the clinical, socio-demographic, and investigational profile of "unknown" patients.

MATERIALS AND METHODS

We did retrospective chart review of all "Unknown" patients from January 2002 to December 2011, who was admitted under Neurology Emergency Service at a Tertiary Care Neuropsychiatry Center in South Indian Metropolitan City. Clinical and sociodemographic characteristics and clinical outcome of the sample were analyzed.

RESULTS

A total of 151 unknown patients were admitted during the 10 years. Out of these, 134 (88.7%) were males with the mean age of 43.8 ± 14.8 years and 95 (63%) were aged >40 years. Among them, 147 (97.4%) were from the urban vicinity, 126 (83.6%) were brought by police and 75 (49.7%) were registered as medico-legal cases. Out of these, only 3 (2%) patients had normal sensorium, whereas 101 (66.9%) presented with loss of consciousness. Forty-one (27.2%) unknown patients had a seizure disorder, 37 (24.5%) had metabolic encephalopathy, 26 (17.2%) had a stroke, 9 (6%) had neuro-infection, and 17 (11.3%) had a head injury. Deranged liver functions were seen in 65 (43%), renal derangement in 37 (24.5%), dyselectrolytemia in 42 (27.8%), and abnormal brain imaging finding in 95 (62.9%) patients. Furthermore, there were 14 (9.3%) deaths.

CONCLUSIONS

Our findings demonstrate seizures, metabolic causes, and neuro-infections were the primary reasons for admission of unknown patients to neuro-emergency service. This novel Indian study data show the common causes of admission of unknown patients in neurology. This pattern can be useful to guide the approach of healthcare providers in India.