Silent Hypoxemia in the Emergency Department: A Retrospective Cohort of Two Clinical Phenotypes in Critical COVID-19.

Introduction: Understanding hypoxemia, with and without the clinical signs of acute respiratory failure (ARF) in COVID-19, is key for management. Hence, from a population of critical patients admitted to the emergency department (ED), we aimed to study silent hypoxemia (Phenotype I) in comparison to symptomatic hypoxemia with clinical signs of ARF (Phenotype II). Methods: This multicenter study was conducted between 1 March and 30 April 2020. Adult patients who were presented to the EDs of nine Great-Eastern French hospitals for confirmed severe or critical COVID-19, who were then directly admitted to the intensive care unit (ICU), were retrospectively included. Results: A total of 423 critical COVID-19 patients were included, out of whom 56.1% presented symptomatic hypoxemia with clinical signs of ARF, whereas 43.9% presented silent hypoxemia. Patients with clinical phenotype II were primarily intubated, initially, in the ED (46%, p < 0.001), whereas those with silent hypoxemia (56.5%, p < 0.001) were primarily intubated in the ICU. Initial univariate analysis revealed higher ICU mortality (29.2% versus 18.8%, p < 0.014) and in-hospital mortality (32.5% versus 18.8%, p < 0.002) in phenotype II. However, multivariate analysis showed no significant differences between the two phenotypes regarding mortality and hospital or ICU length of stay. Conclusions: Silent hypoxemia is explained by various mechanisms, most physiological and unspecific to COVID-19. Survival was found to be comparable in both phenotypes, with decreased survival in favor of Phenotype II. However, the spectrum of silent to symptomatic hypoxemia appears to include a continuum of disease progression, which can brutally evolve into fatal ARF.

Patients with Initial Negative RT-PCR and Typical Imaging of COVID-19: Clinical Implications.

The sensitivity of reverse transcriptase polymerase chain reaction (RT-PCR) has been questioned due to negative results in some patients who were strongly suspected of having coronavirus disease 2019 (COVID-19). The aim of our study was to analyze the prognosis of infected patients with initial negative RT-PCR in the emergency department (ED) during the COVID-19 outbreak. This study included two cohorts of adult inpatients admitted into the ED. All patients who were suspected to be infected with SARS-CoV-2 and who underwent a typical chest CT imaging were included. Thus, we studied two distinct cohorts: patients with positive RT-PCR (PCR+) and those with negative initial RT-PCR (PCR-). The data were analyzed using Bayesian methods. We included 66 patients in the PCR- group and 198 in the PCR+ group. The baseline characteristics did not differ except in terms of a proportion of lower chronic respiratory disease in the PCR- group. We noted a less severe clinical presentation in the PCR- group (lower respiratory rate, lower oxygen need and mechanical ventilation requirement). Hospital mortality (9.1% vs. 9.6%) did not differ between the two groups. Despite an initially less serious clinical presentation, the mortality of patients infected by SARS-CoV-2 with a negative RT-PCR did not differ from those with positive RT-PCR.

Effectiveness of Intubating Laryngeal Mask Airway in managing out-of-hospital cardiac arrest by non-physicians.

AIM OF THE STUDY: The role of supraglottic devices in airway management in out-of-hospital cardiac arrest (OHCA) remains controversial. The aim of this study was to evaluate the feasibility and effectiveness of intubation through the Intubating Laryngeal Mask Airway (ILMA) when used by prehospital emergency nurses in the setting of OHCA. METHODS: We conducted a prospective, observational trial during 12 years by the Fire Department and prehospital emergency service of the health district of Strasbourg, France. The primary outcome was the success rate of ventilation after intubation through the ILMA, while the secondary outcomes were the success rate of ventilation after insertion of the ILMA and complications related to ILMA placement and intubation. Factors associated with successful intubation were also studied. RESULTS: During the study period, 1464 ILMA placements were attempted by emergency nurses during OHCA. Ventilation was possible in 1250 patients (85.38%) after ILMA placement and in 1078 patients (73.63%) after intubation. Regurgitation of gastric contents occurred in 237 (16.18%) patients, mostly during basic life support. Two factors were predictive of a successful tracheal intubation: the performance of the Chandy maneuver OR = 2.91 (CI: 2.07-3.97) and the number of attempts at intubation OR = 1.95 (CI: 1.43-2.61). Conversely, the number of attempts at ILMA insertion was predictive of an intubation failure OR = 0.11 (CI: 0.07-0.17). CONCLUSION: The success rate of intubation through the ILMA was high. After ILMA placement, ventilation was possible in 1250 patients (85.38%) and in 1078 patients (73.63%) after intubation.