Predictors of Urgent Dialysis Following Ambulance Transport to the Emergency Department in Patients Treated With Maintenance Hemodialysis.

Background: Patients receiving maintenance hemodialysis frequently require ambulance transport to the emergency department (ambulance-ED transport). Identifying predictors of outcomes after ambulance-ED transport, especially the need for timely dialysis, is important to health care providers. Objective: The purpose of this study was to derive a risk-prediction model for urgent dialysis after ambulance-ED transport. Design: Observational cohort study. Setting and Patients: All ambulance-ED transports among incident and prevalent patients receiving maintenance hemodialysis affiliated with a regional dialysis program (catchment area of approximately 750 000 individuals) from 2014 to 2018. Measurements: Patients' vital signs (systolic blood pressure, oxygen saturation, respiratory rate, and heart rate) at the time of paramedic transport and time since last dialysis were utilized as predictors for the outcome of interest. The primary outcome was urgent dialysis (defined as dialysis in a monitored setting within 24 hours of ED arrival or dialysis within 24 hours with the first ED patient blood potassium level >6.5 mmol/L) for an unscheduled indication. Secondary outcomes included, hospitalization, hospital length of stay, and in-hospital mortality. Methods: A logistic regression model to predict outcomes of urgent dialysis. Discrimination and calibration were assessed using the C-statistic and Hosmer-Lemeshow test. Results: Among 878 ED visits, 63 (7.2%) required urgent dialysis. Hypoxemia (odds ratio [OR]: 4.04, 95% confidence interval [CI]: 1.75-9.33) and time from last dialysis of 24 to 48 hours (OR: 3.43, 95% CI: 1.05-11.9) and >48 hours (OR: 9.22, 95% CI: 3.37-25.23) were strongly associated with urgent dialysis. A risk-prediction model incorporating patients' vital signs and time from last dialysis had good discrimination (C-statistic 0.8217) and calibration (Hosmer-Lemeshow goodness of fit P value .8899). Urgent dialysis patients were more likely to be hospitalized (63% vs 34%), but there were no differences in inpatient mortality or length of stay. Limitations: Missing data, requires external validation. Conclusion: We derived a risk-prediction model for urgent dialysis that may better guide appropriate transport and care for patients requiring ambulance-ED transport.

Contexte: Les patients sous hémodialyse chronique doivent souvent être transportés au service des urgences par ambulance (transport ambulance-SU). Il est important pour les prestataires de soins de santé que l'on détermine les facteurs prédictifs des résultats après un transport ambulance-SU, en particulier le besoin de dialyze d'urgence. Objectifs: Cette étude visait à établir un modèle de prédiction du risque pour une dialyze d'urgence après un transport ambulance-SU. Type d'étude: Étude de cohorte observationnelle. Participants et cadre de l'étude: Tous les transports ambulance-SU de patients incidents et prévalents recevant une hémodialyse chronique affiliée à un program régional de dialyze (zone desservant environ 750 000 personnes) entre 2014 et 2018. Prédicteurs: Les signes vitaux du patient (pression artérielle systolique, saturation en oxygène, fréquence respiratoire et fréquence cardiaque) au moment du transport par ambulance et le temps écoulé depuis la dernière dialyze. Résultats: La dialyze d'urgence (définie comme une dialyze en environnement monitoré dans les 24 heures suivant l'arrivée aux urgences ou une dialyze dans les 24 heures avec une première mesure du taux de potassium sanguin aux urgences supérieure à 6,5 mmol/L) pour une indication non programmée. Résultats secondaires: hospitalization, durée du séjour à l'hôpital et mortalité à l'hôpital. Méthodologie: Un modèle de régression logistique a servi à prédire le résultat de dialyze d'urgence. La discrimination et la calibration ont été évalués à l'aide de la statistique C et du test Hosmer-Lemeshow. Résultats: Parmi les 878 visites aux urgences, 63 (7,2 %) ont nécessité une dialyze d'urgence. L'hypoxémie (rapport de cote [RC]: 4,04; IC à 95 %: 1,75-9,33) et des périodes de 24 à 48 heures (RC: 3,43; IC à 95 %: 1,05-11,9) et de plus de 48 heures (RC: 9,22; IC à 95 %: 3,37-25,23) depuis la dernière dialyze sont les facteurs qui ont été les plus fortement associés à une dialyze d'urgence. Un modèle de prédiction du risque intégrant les signes vitaux du patient et le temps depuis la dernière dialyze a présenté une bonne discrimination (statistique C: 0,8217) et une bonne calibration (qualité de l'ajustement selon Hosmer-Lemeshow: P =,8899). Les patients qui avaient reçu une dialyze d'urgence étaient plus susceptibles d'être hospitalisés (63% contre 34%), mais aucune différence n'a été observée pour le taux de mortalité ou la durée du séjour en milieu hospitalier. Limites: Données manquantes, validation externe requise. Conclusion: Nous avons dérivé un modèle de prédiction du risque de dialyze d'urgence susceptible de mieux guider le transport et les soins appropriés pour les patients nécessitant un transport ambulance-SU.

Derivation and validation of a clinical decision rule to risk-stratify COVID-19 patients discharged from the emergency department: The CCEDRRN COVID discharge score.

Objective: To risk-stratify COVID-19 patients being considered for discharge from the emergency department (ED). Methods: We conducted an observational study to derive and validate a clinical decision rule to identify COVID-19 patients at risk for hospital admission or death within 72 hours of ED discharge. We used data from 49 sites in the Canadian COVID-19 Emergency Department Rapid Response Network (CCEDRRN) between March 1, 2020, and September 8, 2021. We randomly assigned hospitals to derivation or validation and prespecified clinical variables as candidate predictors. We used logistic regression to develop the score in a derivation cohort and examined its performance in predicting short-term adverse outcomes in a validation cohort. Results: Of 15,305 eligible patient visits, 535 (3.6%) experienced the outcome. The score included age, sex, pregnancy status, temperature, arrival mode, respiratory rate, and respiratory distress. The area under the curve was 0.70 (95% confidence interval [CI] 0.68-0.73) in derivation and 0.71 (95% CI 0.68-0.73) in combined derivation and validation cohorts. Among those with a score of 3 or less, the risk for the primary outcome was 1.9% or less, and the sensitivity of using 3 as a rule-out score was 89.3% (95% CI 82.7-94.0). Among those with a score of ≥9, the risk for the primary outcome was as high as 12.2% and the specificity of using 9 as a rule-in score was 95.6% (95% CI 94.9-96.2). Conclusion: The CCEDRRN COVID discharge score can identify patients at risk of short-term adverse outcomes after ED discharge with variables that are readily available on patient arrival.

Predictors of Hyperkalemia among Patients on Maintenance Hemodialysis Transported to the Emergency Department by Ambulance.

Background: Hyperkalemia is common among patients on maintenance hemodialysis (HD) and is associated with mortality. We hypothesized that clinical characteristics available at time of paramedic assessment before emergency department (ED) ambulance transport (ambulance-ED) would associate with severe hyperkalemia (K≥6 mmol/L). Rapid identification of patients who are at risk for hyperkalemia and thereby hyperkalemia-associated complications may allow paramedics to intervene in a timely fashion, including directing emergency transport to dialysis-capable facilities. Methods: Patients on maintenance HD from a single paramedic provider region, who had at least one ambulance-ED and subsequent ED potassium from 2014 to 2018, were examined using multivariable logistic regression to create risk prediction models inclusive of prehospital vital signs, days from last dialysis, and the presence of prehospital electrocardiogram (ECG) features of hyperkalemia. We used bootstrapping with replacement to validate each model internally, and performance was assessed by discrimination and calibration. Results: Among 704 ambulance-ED visits, severe hyperkalemia occurred in 75 (11%); 26 patients with ED hyperkalemia did not have a prehospital ECG. Younger age at transport, longer HD vintage, more days from last hemodialysis session (OR=49.84; 95% CI, 7.72 to 321.77 for ≥3 days versus HD the same day [before] ED transport), and prehospital ECG changes (OR=6.64; 95% CI, 2.31 to 19.12) were independently associated with severe ED hyperkalemia. A model incorporating these factors had good discrimination (c-statistic 0.82; 95% CI, 0.76 to 0.89) and, using a cutoff of 25% probability, correctly classified patients 89% of the time. Conclusions: Characteristics available at the time of ambulance-ED were associated with severe ED hyperkalemia. An awareness of these associations may allow health care providers to define novel care pathways to ensure timely diagnosis and management of hyperkalemia.

CO-aVoID: coronavirus outbreak affecting variability of presentations to a local emergency department.

BACKGROUND: The impact of the COVID-19 pandemic on public health, specifically on patients presenting to the emergency department (ED) with non-COVID-related diseases, remains largely undocumented. OBJECTIVE: This study explored how overall rates of presentations to the emergency department were impacted immediately after the declaration of the COVID-19 pandemic, and specifically how key presenting symptoms representing emergency, standard and low-acuity conditions were impacted. METHODS: A sequential modified Delphi survey and cross-sectional analysis of administrative census data from a tertiary care center in New Brunswick, Canada, were performed. Details of ED presentations for emergency, standard and low-acuity conditions from February 1 to April 30, 2020, were compared to data from previous years. RESULTS: There was a significant decrease in the number of patients visiting the ED with emergency, standard and low-acuity complaints immediately after March 13, 2020, compared to 2019. The proportion of females and males remained similar, with a median age of 48 years in 2020 and 44 years in 2019. Total presentation patterns to the ED (registrations, admissions to hospital and left without being seen numbers) decreased, compared to previous years. CONCLUSIONS: We report a predictable decrease in patient visits to the ED with minor, non-life-threatening conditions during a pandemic. However, we also report a decrease in presentations for emergency and standard conditions. Improved messaging highlighting the need to seek help for "true" emergencies, while providing non-ED options for minor, non-life-threatening conditions, may be helpful under normal circumstances and during future pandemics.

RéSUMé: CONTEXTE: L'impact de la pandémie COVID-19 sur la santé publique, en particulier sur les patients se présentant aux services d'urgence (SU) avec des maladies non liées à la COVID, demeure en grande partie non documenté. OBJECTIF: Cette étude a exploré la façon dont les taux globaux de présentations au service des urgences ont été touchés immédiatement après la déclaration de la pandémie de COVID-19, et plus particulièrement la façon dont les principaux symptômes représentant des conditions d'urgence, standard et de faible acuité ont été touchés. MéTHODES: Une enquête Delphi séquentielle modifiée et une analyse transversale des données du recensement administratif provenant d'un centre de soins tertiaires du Nouveau-Brunswick, au Canada, ont été réalisées. Les détails des présentations du SU pour les conditions d'urgence, standard et de faible acuité du 1er février au 30 avril 2020 ont été comparés aux données des années précédentes. RéSULTATS: Il y a eu une diminution significative du nombre de patients se rendant au service d'urgence avec des plaintes d'urgence, standard et de faible gravité immédiatement après le 13 mars 2020, par rapport à 2019. La proportion de femmes et d'hommes est demeurée semblable, avec un âge médian de 48 ans en 2020 et de 44 ans en 2019. Le nombre total de modèles de présentation à l'urgence (inscriptions, admissions à l'hôpital et nombre laissé sans être vu) a diminué par rapport aux années précédentes. CONCLUSIONS: Nous faisons état d'une diminution prévisible des visites de patients aux urgences pour des affections mineures qui ne mettent pas leur vie en danger pendant une pandémie. Toutefois, nous signalons également une diminution des présentations pour les situations d'urgence et les conditions normales. Des messages améliorés soulignant la nécessité de demander de l'aide pour les urgences « réelles ¼, tout en offrant des options non urgentes pour des conditions mineures et qui ne mettent pas la vie en danger peuvent être utiles dans des circonstances normales et lors de futures pandémies.

Development of the Canadian COVID-19 Emergency Department Rapid Response Network population-based registry: a methodology study.

BACKGROUND: Emergency physicians lack high-quality evidence for many diagnostic and treatment decisions made for patients with suspected or confirmed coronavirus disease 2019 (COVID-19). Our objective is to describe the methods used to collect and ensure the data quality of a multicentre registry of patients presenting to the emergency department with suspected or confirmed COVID-19. METHODS: This methodology study describes a population-based registry that has been enrolling consecutive patients presenting to the emergency department with suspected or confirmed COVID-19 since Mar. 1, 2020. Most data are collected from retrospective chart review. Phone follow-up with patients at 30 days captures the World Health Organization clinical improvement scale and contextual, social and cultural variables. Phone follow-up also captures patient-reported quality of life using the Veterans Rand 12-Item Health Survey at 30 days, 60 days, 6 months and 12 months. Fifty participating emergency departments from 8 provinces in Canada currently enrol patients into the registry. INTERPRETATION: Data from the registry of the Canadian COVID-19 Emergency Department Rapid Response Network will be used to derive and validate clinical decision rules to inform clinical decision-making, describe the natural history of the disease, evaluate COVID-19 diagnostic tests and establish the real-world effectiveness of treatments and vaccines, including in populations that are excluded or underrepresented in clinical trials. This registry has the potential to generate scientific evidence to inform our pandemic response, and to serve as a model for the rapid implementation of population-based data collection protocols for future public health emergencies. TRIAL REGISTRATION: Clinicaltrials.gov, no. NCT04702945.

Procedural sedation by advanced care paramedics for emergency gastrointestinal endoscopy.

OBJECTIVES: At the QEII Health Sciences Centre Emergency Department (ED) in Halifax, Nova Scotia, advanced care paramedics (ACPs) perform procedural sedation and analgesia (PSA) for many indications, including orthopedic procedures. We have begun using ACPs as sedationists for emergent upper gastrointestinal (UGI) endoscopy. This study compares ACP-performed ED PSA for UGI endoscopy and orthopedic procedures in terms of adverse events, airway intervention, vasopressor requirement, and PSA medication use. METHODS: A data set was built from an ED PSA quality control database matching 61 UGI endoscopy PSAs to 183 orthopedic PSAs by propensity scores calculated using age, gender, and the American Society of Anesthesiologists (ASA) classification. Outcomes assessed were hypotension (systolic BP30 sec), vomiting, arrhythmias, death, airway intervention, vasopressor requirement, and PSA medication use. RESULTS: UGI endoscopy patients experienced hypotension more frequently than orthopedic patients (OR=4.11, CI: 2.05-8.22) and required airway repositioning less often (OR=0.24, CI: 0.10-0.59). They received ketamine more frequently (OR=15.7, CI: 4.75-67.7) and fentanyl less often (OR=0.30, CI: 0.15-0.63) than orthopedic patients. Four endoscopy patients received phenylephrine, and one required intubation. No patient died in either group. CONCLUSIONS: In ACP-led sedation for UGI endoscopy and orthopedic procedures, adverse events were rare with the notable exception of hypotension, which was more frequent in the endoscopy group. Only endoscopy patients required vasopressor treatment and intubation. We provide preliminary evidence that ACPs can manage ED PSA for emergent UGI endoscopy, although priorities must shift from pain control to hemodynamic optimization.

Pre-synaptic defects of NPC1-deficient hippocampal neurons are not directly related to plasma membrane cholesterol.

Imbalances in brain cholesterol homeostasis have been observed in several neurodegenerative diseases. In Niemann-Pick Type C (NPC) disease, mutations in NPC1 or NPC2 lead to endosomal cholesterol accumulation, neuronal dysfunction and death. Cholesterol in synaptic plasma membranes influences membrane fluidity, curvature, and protein function, and its depletion may adversely affect synaptic vesicle cycling. We have investigated pre-synaptic function in primary hippocampal neurons with altered cholesterol distribution because of NPC1 deficiency or cyclodextrin treatment. In NPC1-deficient neurons grown in serum-free medium, plasma membrane cholesterol was reduced and total synaptic vesicle release during prolonged stimulation was attenuated. In NPC1-deficient neurons cultured in the presence of high-density lipoproteins, plasma membrane cholesterol markedly increased, but the defects in synaptic vesicle release in NPC1-deficient neurons were exacerbated. Treatment with 1 mM methyl-beta-cyclodextrin acutely depleted plasma membrane cholesterol in wild-type neurons to levels below those in NPC1 deficiency, but did not alter synaptic vesicle exo- or endocytosis. Defects only became apparent when higher methyl-beta-cyclodextrin concentrations were used. Our data indicate that synaptic vesicle release can tolerate some degree of plasma membrane cholesterol depletion and suggest that the pre-synaptic defects in NPC1-deficient neurons are not solely caused by a reduction of plasma membrane cholesterol.