The Response of Emergency Departments (EDs) to the COVID-19 Pandemic: The Experience of 5 EDs in a Paris-Based Academic Hospital Trust.

The coronavirus disease-2019 (COVID-19) pandemic has imposed unforeseen and unprecedented constraints on emergency departments (EDs). In this study, we detail the organizational and managerial tools recently implemented among 5 academic EDs in a French region particularly affected by COVID-19 and analyze how EDs responded to the COVID-19-related disease burden during different phases of the epidemic. Initially, they focused on the early detection of suspected cases by identifying 3 predominant COVID-19 syndromes. During this diagnostic process, patients were placed in respiratory isolation (facial mask before triage) and droplet isolation (ED rooms). A 3-level strategy for triage, clinical pathways in the EDs, and the organization of hospital spaces was based on the real-time polymerase chain reaction (RT-PCR) COVID-19 positivity rate, with ED strategies adapted to the exigencies of each level. This crisis demonstrated hospitals' adaptability and capacity to mobilize in the face of new risks, with hospitals and EDs coordinating their management to reallocate resources, optimize interoperability, and rethink patient pathways. This report on their processes may assist hospitals and EDs in areas currently spared by the new variants.

Clinical Characteristics and Management of Patients with a Suspected COVID-19 Infection in Emergency Departments: A European Retrospective Multicenter Study.

Background: Our aim is to describe and compare the profile and outcome of patients attending the ED with a confirmed COVID-19 infection with patients with a suspected COVID-19 infection. Methods: We conducted a multicentric retrospective study including adults who were seen in 21 European emergency departments (ED) with suspected COVID-19 between 9 March and 8 April 2020. Patients with either a clinical suspicion of COVID-19 or confirmed COVID-19, detected using either a RT-PCR or a chest CT scan, formed the C+ group. Patients with non-confirmed COVID-19 (C− group) were defined as patients with a clinical presentation in the ED suggestive of COVID-19, but if tests were performed, they showed a negative RT-PCR and/or a negative chest CT scan. Results: A total of 7432 patients were included in the analysis: 1764 (23.7%) in the C+ group and 5668 (76.3%) in the C− group. The population was older (63.8 y.o. ±17.5 vs. 51.8 y.o. +/− 21.1, p < 0.01), with more males (54.6% vs. 46.1%, p < 0.01) in the C+ group. Patients in the C+ group had more chronic diseases. Half of the patients (n = 998, 56.6%) in the C+ group needed oxygen, compared to only 15% in the C− group (n = 877). Two-thirds of patients from the C+ group were hospitalized in ward (n = 1128, 63.9%), whereas two-thirds of patients in the C− group were discharged after their ED visit (n = 3883, 68.5%). Conclusion: Our study was the first in Europe to examine the emergency department's perspective on the management of patients with a suspected COVID-19 infection. We showed an overall more critical clinical situation group of patients with a confirmed COVID-19 infection.

Comparison of Patients Infected With Delta Versus Omicron COVID-19 Variants Presenting to Paris Emergency Departments : A Retrospective Cohort Study.

BACKGROUND: At the end of 2021, the B.1.1.529 SARS-CoV-2 variant (Omicron) wave superseded the B.1.617.2 variant (Delta) wave. OBJECTIVE: To compare baseline characteristics and in-hospital outcomes of patients with SARS-CoV-2 infection with the Delta variant versus the Omicron variant in the emergency department (ED). DESIGN: Retrospective chart reviews. SETTING: 13 adult EDs in academic hospitals in the Paris area from 29 November 2021 to 10 January 2022. PATIENTS: Patients with a positive reverse transcriptase polymerase chain reaction (RT-PCR) test result for SARS-CoV-2 and variant identification. MEASUREMENTS: Main outcome measures were baseline clinical and biological characteristics at ED presentation, intensive care unit (ICU) admission, mechanical ventilation, and in-hospital mortality. RESULTS: A total of 3728 patients had a positive RT-PCR test result for SARS-CoV-2 during the study period; 1716 patients who had a variant determination (818 Delta and 898 Omicron) were included. Median age was 58 years, and 49% were women. Patients infected with the Omicron variant were younger (54 vs. 62 years; difference, 8.0 years [95% CI, 4.6 to 11.4 years]), had a lower rate of obesity (8.0% vs. 12.5%; difference, 4.5 percentage points [CI, 1.5 to 7.5 percentage points]), were more vaccinated (65% vs. 39% for 1 dose and 22% vs. 11% for 3 doses), had a lower rate of dyspnea (26% vs. 50%; difference, 23.6 percentage points [CI, 19.0 to 28.2 percentage points]), and had a higher rate of discharge home from the ED (59% vs. 37%; difference, 21.9 percentage points [-26.5 to -17.1 percentage points]). Compared with Delta, Omicron infection was independently associated with a lower risk for ICU admission (adjusted difference, 11.4 percentage points [CI, 8.4 to 14.4 percentage points]), mechanical ventilation (adjusted difference, 3.6 percentage points [CI, 1.7 to 5.6 percentage points]), and in-hospital mortality (adjusted difference, 4.2 percentage points [CI, 2.0 to 6.5 percentage points]). LIMITATION: Patients with COVID-19 illness and no SARS-CoV-2 variant determination in the ED were excluded. CONCLUSION: Compared with the Delta variant, infection with the Omicron variant in patients in the ED had different clinical and biological patterns and was associated with better in-hospital outcomes, including higher survival. PRIMARY FUNDING SOURCE: None.

Identifying SARS-COV-2 infected patients through canine olfactive detection on axillary sweat samples; study of observed sensitivities and specificities within a group of trained dogs.

There is an increasing need for rapid, reliable, non-invasive, and inexpensive mass testing methods as the global COVID-19 pandemic continues. Detection dogs could be a possible solution to identify individuals infected with SARS-CoV-2. Previous studies have shown that dogs can detect SARS-CoV-2 on sweat samples. This study aims to establish the dogs' sensitivity (true positive rate) which measures the proportion of people with COVID-19 that are correctly identified, and specificity (true negative rate) which measures the proportion of people without COVID-19 that are correctly identified. Seven search and rescue dogs were tested using a total of 218 axillary sweat samples (62 positive and 156 negative) in olfaction cones following a randomised and double-blind protocol. Sensitivity ranged from 87% to 94%, and specificity ranged from 78% to 92%, with four dogs over 90%. These results were used to calculate the positive predictive value and negative predictive value for each dog for different infection probabilities (how likely it is for an individual to be SARS-CoV-2 positive), ranging from 10-50%. These results were compared with a reference diagnostic tool which has 95% specificity and sensitivity. Negative predictive values for six dogs ranged from ≥98% at 10% infection probability to ≥88% at 50% infection probability compared with the reference tool which ranged from 99% to 95%. Positive predictive values ranged from ≥40% at 10% infection probability to ≥80% at 50% infection probability compared with the reference tool which ranged from 68% to 95%. This study confirms previous results, suggesting that dogs could play an important role in mass-testing situations. Future challenges include optimal training methods and standardisation for large numbers of detection dogs and infrastructure supporting their deployment.

Pulmonary embolism severity and in-hospital mortality: An international comparative study between COVID-19 and non-COVID patients.

OBJECTIVE: To compare the severity of pulmonary embolism (PE) between patients with and without COVID, and to assess the association between severity and in-hospital-mortality. METHODS: We performed an analysis of 549 COVID (71.3% PCR-confirmed) and 439 non-COVID patients with PE consecutively included by 62 Spanish and 16 French emergency departments. PE-severity was assessed by size, the presence of right ventricular dysfunction (RVD), and the sPESI. The association of PE-severity and in-hospital-mortality was assessed both in COVID and non-COVID patients, and the interaction of COVID status and PE severity/outcome associations was also evaluated. RESULTS: COVID patients had PEs of smaller size (43% vs 56% lobar or larger, 42% vs. 35% segmental and 13% vs. 9% subsegmental, respectively; p = 0.01 for trend), less RVD (22% vs. 16%, p =0.02) and lower sPESI (p =0.03 for trend). Risk of in-hospital death was higher in COVID patients (12.8% vs. 5.3%, p < 0.001). PE-severity assessed by RVD and sPESI was independently associated with in-hospital-mortality in COVID patients, while PE size and sPESI were significantly associated with in-hospital-mortality in non-COVID. COVID status showed a significant interaction in the association of PE size and outcome (p =0.01), with OR for in-hospital mortality in COVID and non-COVID patients with lobar or larger PE of 0.92 (95%CI=0.19-4.47) and 4.47 (95%CI=1.60-12.5), respectively. Sensitivity analyses using only PCR-confirmed COVID cases confirmed these results. CONCLUSION: COVID patients present a differential clinical picture, with PE of less severity than in non-COVID patients. An increased sPESI was associated with the risk of mortality in both groups but, PE size did not seem to be associated with in-hospital mortality in COVID patients.

Outpatient Management of Patients With COVID-19: Multicenter Prospective Validation of the Hospitalization or Outpatient Management of Patients With SARS-CoV-2 Infection Rule to Discharge Patients Safely.

BACKGROUND: The Hospitalization or Outpatient Management of Patients With SARS-CoV-2 Infection (HOME-CoV) rule is a checklist of eligibility criteria for home treatment of patients with COVID-19, defined using a Delphi method. RESEARCH QUESTION: Is the HOME-CoV rule reliable for identifying a subgroup of COVID-19 patients with a low risk of adverse outcomes who can be treated at home safely? STUDY DESIGN AND METHODS: We aimed to validate the HOME-CoV rule in a prospective, multicenter study before and after trial of patients with probable or confirmed COVID-19 who sought treatment at the ED of 34 hospitals. The main outcome was an adverse evolution, that is, invasive ventilation or death, occurring within the 7 days after patient admission. The performance of the rule was assessed by the false-negative rate. The impact of the rule implementation was assessed by the absolute differences in the rate of patients who required invasive ventilation or who died and in the rate of patients treated at home, between an observational and an interventional period after implementation of the HOME-CoV rule, with propensity score adjustment. RESULTS: Among 3,000 prospectively enrolled patients, 1,239 (41.3%) demonstrated a negative HOME-CoV rule finding. The false-negative rate of the HOME-CoV rule was 4 in 1,239 (0.32%; 95% CI, 0.13%-0.84%), and its area under the receiver operating characteristic curve was 80.9 (95% CI, 76.5-85.2). On the adjusted populations, 25 of 1,274 patients (1.95%) experienced an adverse evolution during the observational period vs 12 of 1,274 patients (0.95%) during the interventional period: -1.00 (95% CI, -1.86 to -0.15). During the observational period, 858 patients (67.35%) were treated at home vs 871 patients (68.37%) during the interventional period: -1.02 (95% CI, -4.46 to 2.26). INTERPRETATION: A large proportion of patients treated in the ED with probable or confirmed COVID-19 have a negative HOME-CoV rule finding and can be treated safely at home with a very low risk of complications. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT04338841; URL: www.clinicaltrials.gov.

White blood count, D-dimers, and ferritin levels as predictive factors of pulmonary embolism suspected upon admission in noncritically ill COVID-19 patients: The French multicenter CLOTVID retrospective study.

BACKGROUND: A high prevalence of pulmonary embolism (PE) has been described during COVID-19. Our aim was to identify predictive factors of PE in non-ICU hospitalized COVID-19 patients. METHODS: Data and outcomes were collected upon admission during a French multicenter retrospective study, including patients hospitalized for COVID-19, with a CT pulmonary angiography (CTPA) performed in the emergency department for suspected PE. Predictive factors significantly associated with PE were identified through a multivariate regression model. RESULTS: A total of 88 patients (median [IQR] age of 68 years [60-78]) were analyzed. Based on CTPA, 47 (53.4%) patients were diagnosed with PE, and 41 were not. D-dimer ≥3000 ng/mL (OR 8.2 [95% CI] 1.3-74.2, sensitivity (Se) 0.84, specificity (Sp) 0.78, P = .03), white blood count (WBC) ≥12.0 G/L (29.5 [2.3-1221.2], Se 0.47, Sp 0.92, P = .02), and ferritin ≥480 µg/L (17.0 [1.7-553.3], Se 0.96, Sp 0.44, P = .03) were independently associated with the PE diagnosis. The presence of the double criterion D-dimer ≥3000 ng/mL and WBC ≥12.0 G/L was greatly associated with PE (OR 21.4 [4.0-397.9], P = .004). CONCLUSION: The white blood count, the D-dimer and ferritin levels could be used as an indication for CTPA to confirm PE on admission in non-ICU COVID-19 patients.

D-Dimer Level and Neutrophils Count as Predictive and Prognostic Factors of Pulmonary Embolism in Severe Non-ICU COVID-19 Patients.

The incidence of pulmonary embolism (PE) is high during severe Coronavirus Disease 2019 (COVID-19). We aimed to identify predictive and prognostic factors of PE in non-ICU hospitalized COVID-19 patients. In the retrospective multicenter observational CLOTVID cohort, we enrolled patients with confirmed RT-PCR COVID-19 who were hospitalized in a medicine ward and also underwent a CT pulmonary angiography for a PE suspicion. Baseline data, laboratory biomarkers, treatments, and outcomes were collected. Predictive and prognostics factors of PE were identified by using logistic multivariate and by Cox regression models, respectively. A total of 174 patients were enrolled, among whom 86 (median [IQR] age of 66 years [55-77]) had post-admission PE suspicion, with 30/86 (34.9%) PE being confirmed. PE occurrence was independently associated with the lack of long-term anticoagulation or thromboprophylaxis (OR [95%CI], 72.3 [3.6-4384.8]) D-dimers ≥ 2000 ng/mL (26.3 [4.1-537.8]) and neutrophils ≥ 7.0 G/L (5.8 [1.4-29.5]). The presence of these two biomarkers was associated with a higher risk of PE (p = 0.0002) and death or ICU transfer (HR [95%CI], 12.9 [2.5-67.8], p < 0.01). In hospitalized non-ICU severe COVID-19 patients with clinical PE suspicion, the lack of anticoagulation, D-dimers ≥ 2000 ng/mL, neutrophils ≥ 7.0 G/L, and these two biomarkers combined might be useful predictive markers of PE and prognosis, respectively.

Definition and Validation of a Risk-Stratification Model for Probable or Proven COVID-19 Patients in Emergency Departments: The Revised HOME-CoV Score. (preprint)

The HOME-CoV rule is a list of clinical criteria defined by experts’ consensus, qualifying patients with probable or proven COVID-19 for home treatment when negative. The aims were to define and validate a revised HOME-CoV score, optimizing the original rule. Definition of the revised HOME-CoV score using logistic regression in a prospective multicenter cohort and validation in another cohort of patients who presented to the emergency department with proven or probable COVID-19. The main outcome was non-invasive or invasive ventilation or all-cause death within the 7 days following inclusion. Two threshold values were defined using a sensitivity of > 0.9 and a specificity of > 0.9 to identify low-risk patients and high-risk patients, respectively. The revised HOME-CoV score included seven clinical criteria. In the definition cohort (n=1696), the AUC was 87.6 (95% CI 84.7 to 90.6). The cutoffs to define low-risk and high-risk patients were <2 and >3, respectively. In the validation cohort (n=1304), the AUC was 85.8 (95% CI 80.6 to 91.0) and 85.5 (95% CI 76.8 to 94.1) in the subgroup of patients with positive RT-PCR for SARS-CoV2. A score of < 2 qualified 73% of patients as low risk with a sensitivity of 0.84 (0.66-0.95) and a negative predictive value of 0.99 (0.99-1.00). The revised HOME-CoV score compared favorably with the original rule and other models. The revised HOME-CoV score may allow accurate risk stratification and safely qualify for home treatment, a significant proportion of patients with probable or proven COVID-19.

Evaluating 10 Commercially Available SARS-CoV-2 Rapid Serological Tests by Use of the STARD (Standards for Reporting of Diagnostic Accuracy Studies) Method.

Numerous severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) rapid serological tests have been developed, but their accuracy has usually been assessed using very few samples, and rigorous comparisons between these tests are scarce. In this study, we evaluated and compared 10 commercially available SARS-CoV-2 rapid serological tests using the STARD (Standards for Reporting of Diagnostic Accuracy Studies) methodology. Two hundred fifty serum samples from 159 PCR-confirmed SARS-CoV-2 patients (collected 0 to 32 days after the onset of symptoms) were tested with rapid serological tests. Control serum samples (n = 254) were retrieved from pre-coronavirus disease (COVID) periods from patients with other coronavirus infections (n = 11), positivity for rheumatoid factors (n = 3), IgG/IgM hyperglobulinemia (n = 9), malaria (n = 5), or no documented viral infection (n = 226). All samples were tested using rapid lateral flow immunoassays (LFIAs) from 10 manufacturers. Only four tests achieved ≥98% specificity, with the specificities ranging from 75.7% to 99.2%. The sensitivities varied by the day of sample collection after the onset of symptoms, from 31.7% to 55.4% (days 0 to 9), 65.9% to 92.9% (days 10 to 14), and 81.0% to 95.2% (>14 days). Only three of the tests evaluated met French health authorities' thresholds for SARS-CoV-2 serological tests (≥90% sensitivity and ≥98% specificity). Overall, the performances varied greatly between tests, with only one-third meeting acceptable specificity and sensitivity thresholds. Knowledge of the analytical performances of these tests will allow clinicians and, most importantly, laboratorians to use them with more confidence; could help determine the general population's immunological status; and may help diagnose some patients with false-negative real-time reverse transcription-PCR (RT-PCR) results.

Analysis of Emergency Department Visits and Hospital Activity during Influenza Season, COVID-19 Epidemic, and Lockdown Periods in View of Managing a Future Disaster Risk: A Multicenter Observational Study.

ED-visits and through-ED admissions to medical/surgical wards (MSW) and intensive care unit (ICU) during influenza, COVID-19 and lockdown periods were evaluated in a four-hospital prospective observational study from November 2018 to March 2020. ED visit characteristics and main diagnostic categories were assessed. Analysis of 368,262 ED-visits highlighted a significantly increasing trend in ED-visits during influenza followed by a significantly decreasing trend after lockdown. For MSW-admissions, a pattern of growth during influenza was followed by a fall that began during COVID-19 pandemic and intensified during the lockdown. For ICU-admissions, a significant rise during the COVID-19 pandemic was followed by diminution during the lockdown period. During lockdown, significantly diminishing trends were shown for all diagnostic categories (between -40.8% and -73.6%), except influenza-like illness/COVID cases (+31.6%), Pulmonary embolism/deep vein thrombosis (+33.5%) and frequent users (+188.0%). The present study confirms an increase in demand during the influenza epidemic and during the initial phase of the COVID-19 epidemic, but a drop in activity during the lockdown, mainly related to non-COVID conditions. Syndromic surveillance of ILI cases in ED is a tool for monitoring influenza and COVID-19, and it can predict ED activity and the need for MSW and ICU beds.

Association Between Pulmonary Embolism and COVID-19 in Emergency Department Patients Undergoing Computed Tomography Pulmonary Angiogram: The PEPCOV International Retrospective Study.

BACKGROUND: There have been reports of procoagulant activity in patients with COVID-19. Whether there is an association between pulmonary embolism (PE) and COVID-19 in the emergency department (ED) is unknown. The aim of this study was to assess whether COVID-19 is associated with PE in ED patients who underwent a computed tomographic pulmonary angiogram (CTPA). METHODS: A retrospective study in 26 EDs from six countries. ED patients in whom a CTPA was performed for suspected PE during a 2-month period covering the pandemic peak. The primary endpoint was the occurrence of a PE on CTPA. COVID-19 was diagnosed in the ED either on CT or reverse transcriptase-polymerase chain reaction. A multivariable binary logistic regression was built to adjust with other variables known to be associated with PE. A sensitivity analysis was performed in patients included during the pandemic period. RESULTS: A total of 3,358 patients were included, of whom 105 were excluded because COVID-19 status was unknown, leaving 3,253 for analysis. Among them, 974 (30%) were diagnosed with COVID-19. Mean (±SD) age was 61 (±19) years and 52% were women. A PE was diagnosed on CTPA in 500 patients (15%). The risk of PE was similar between COVID-19 patients and others (15% in both groups). In the multivariable binary logistic regression model, COVID-19 was not associated with higher risk of PE (adjusted odds ratio = 0.98, 95% confidence interval = 0.76 to 1.26). There was no association when limited to patients in the pandemic period. CONCLUSION: In ED patients who underwent CTPA for suspected PE, COVID-19 was not associated with an increased probability of PE diagnosis. These results were also valid when limited to the pandemic period. However, these results may not apply to patients with suspected COVID-19 in general.