ABSTRACT
Soon after the emergence and global spread of a new severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron lineage, BA.1 (ref1, 2), another Omicron lineage, BA.2, has initiated outcompeting BA.1. Statistical analysis shows that the effective reproduction number of BA.2 is 1.4-fold higher than that of BA.1. Neutralisation experiments show that the vaccine-induced humoral immunity fails to function against BA.2 like BA.1, and notably, the antigenicity of BA.2 is different from BA.1. Cell culture experiments show that BA.2 is more replicative in human nasal epithelial cells and more fusogenic than BA.1. Furthermore, infection experiments using hamsters show that BA.2 is more pathogenic than BA.1. Our multiscale investigations suggest that the risk of BA.2 for global health is potentially higher than that of BA.1.
Subject(s)
Coronavirus InfectionsABSTRACT
Background: The COVID-19 pandemic has created a need for educational materials and methods that can replace clinical clerkships (CCs) for online simulated clinical practice (online-sCP). This study evaluates the impact of using simulated electronic health records (sEHR) for inpatients, and electronic problem-based learning (e-PBL) and online virtual medical interviews (online-VMI) for outpatients, for an online-sCP using a learning management system (LMS) and online meeting system facilitated by a supervising physician. Methods: : The sEHR was reviewed by medical students and subsequently discussed with a supervising physician using an online meeting system. In the e-PBL, medical students reviewed the simulated patients and discussed on the LMS. For the online-VMI, a faculty member acted as an outpatient and a student acted as the doctor. Small groups of students discussed the clinical reasoning process using the online meeting system. A mixed-method design was implemented. Medical students self-assessed their clinical competence before and after the online-sCP. They answered questionnaires and participated in semi-structured focus group interviews (FGIs) regarding the advantages and disadvantages of the practice. Results: : Forty-three students completed the online-sCP during May and June 2020. All students indicated significant improvement in all aspects of self-evaluation of clinical performance after the online-sCP. Students using sEHR reported significant improvement in writing daily medical records and medical summaries. Students using e-PBL and online-VMI reported significant improvement in medical interviews and counseling. Students also indicated CCs as more useful for learning associated with medical interviews, physical examinations, and humanistic qualities like professionalism than the online-sCP. Eight FGIs were conducted ( n = 42). The advantages of online-sCP were segregated into five categories (learning environment, efficiency, accessibility, self-paced learning, and interactivity); meanwhile, the disadvantages of online-sCP were classified into seven categories (clinical practice experience, learning environment, interactivity, motivation, memory retention, accessibility, and extraneous cognitive load). Conclusions: : Online-sCP with sEHR, e-PBL, and online-VMI could be useful in learning some of the clinical skills acquired through CC. These methods can be implemented with limited preparation and resources.
Subject(s)
COVID-19 , Learning DisabilitiesABSTRACT
Background: Coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 has become a global pandemic, and those developing critically ill conditions have been reported to have mortality in the range of 39% to 61%. Due to the lack of definitive treatments, mechanical ventilation and supportive oxygenation therapy are key management strategies for the survival of patients with acute respiratory distress syndrome (ARDS). Optimizing oxygenation therapy is mandatory to treat patients with severe respiratory failure, to sufficiently compensate for the oxygen (O2) demand. We experienced a case of severe ARDS due to COVID-19 successfully treated with extracorporeal membrane oxygenation (ECMO) after increasing oxygen delivery according to O2 consumption measurement by indirect calorimetryCase Presentation: A 29-year-old obese but otherwise healthy man was hospitalized for treatment of COVID-19 pneumonia presenting with a 4-day history of persisting cough, high fever, and dyspnea. Mechanical ventilation, nitric oxide inhalation, and prone positioning were initiated in the ICU against severe respiratory dysfunction. Indirect calorimetry on the 3rd and 6th ICU days revealed persistent elevation of oxygen consumption (VO2) of 380 mL/min. Veno-venous ECMO was initiated on the 7th ICU day after further deterioration of respiratory failure. Periodic events of SpO2 decline due to effortful breathing was not resolved by neuromuscular blockade in attempt to reduce O2 consumption. Increasing the ECMO flow induced hemolysis and hyperkalemia despite the use of large bore cannulas and ECMO circuit free of clots and defects. The hemoglobin management level was elevated from 10 g/dL to 13 g/dL to increase blood oxygen capacity, enabling the reduction of ECMO flow while attenuating respiratory effort and maintaining SpO2. Lung protective ventilation strategy and prone positioning were continued for successful weaning from ECMO on the 16th ICU day, and the ventilator on the 18th ICU day.Conclusion: The present case of severe ARDS due to COVID-19 was successfully treated with ECMO. Enhancing oxygen delivery was crucial to compensate for the elevated O2 demand. Measuring O2 consumption by indirect calorimetry can elucidate the oxygen demand for optimizing the oxygenation therapy for successful management and survival of critically ill COVID-19 patients.