Using the prone position could help to combat the development of fast hypoxia in some patients with COVID-19

High Flow Nasal Cannula Therapy in the Emergency Department: Main Benefits in Adults, Pediatric Population and against COVID-19: A Narrative Review

This review aims to summarize the literature’s main results about high flow nasal cannula therapy (HFNC) HFNC benefits in the Emergency Department (ED) in adults and pediatrics, including new Coronavirus Disease (COVID-19). HFNC has recently been established as the usual treatment in the ED to provide oxygen support. Its use has been generalized due to its advantages over traditional oxygen therapy devices, including decreased nasopharyngeal resistance, washing out of the nasopharyngeal dead space, generation of positive pressure, increasing alveolar recruitment, easy adaptation due to the humidification of the airways, increased fraction of inspired oxygen and improved mucociliary clearance. A wide range of pathologies has been studied to evaluate the potential benefits of HFNC; some examples are heart failure, pneumonia, chronic pulmonary obstructive disease, asthma, and bronchiolitis. The regular use of this oxygen treatment is not established yet due to the literature’s controversial results. However, several authors suggest that it could be useful in several pathologies that generate acute respiratory failure. Consequently, the COVID-19 irruption has generated the question of HFNC as a safety and effective treatment. Our results suggested that HFNC seems to be a useful tool in the ED, especially in patients affected by acute hypoxemic respiratory failure, acute heart failure, pneumonia, bronchiolitis, asthma and acute respiratory distress syndrome in patients affected by COVID-19. Its benefits in hypercapnic respiratory failure are more discussed, being only observed benefits in patients with mild-moderate disease. These results are based in clinical as well as cost-effectiveness outcomes. Future studies with largest populations are required to confirm these results as well as establish a practical guideline to use this device.

Neurological complications and infection mechanism of SARS-COV-2

Currently, SARS-CoV-2 has caused a global pandemic and threatened many lives. Although SARS-CoV-2 mainly causes respiratory diseases, growing data indicate that SARS-CoV-2 can also invade the central nervous system (CNS) and peripheral nervous system (PNS) causing multiple neurological diseases, such as encephalitis, encephalopathy, Guillain-Barré syndrome, meningitis, and skeletal muscular symptoms. Despite the increasing incidences of clinical neurological complications of SARS-CoV-2, the precise neuroinvasion mechanisms of SARS-CoV-2 have not been fully established. In this review, we primarily describe the clinical neurological complications associated with SARS-CoV-2 and discuss the potential mechanisms through which SARS-CoV-2 invades the brain based on the current evidence. Finally, we summarize the experimental models were used to study SARS-CoV-2 neuroinvasion. These data form the basis for studies on the significance of SARS-CoV-2 infection in the brain.

Awake Prone Positioning in the Management of COVID-19 Pneumonia: A Systematic Review

Background: The aim was to investigate the efficacy of prone positioning (PP) in the management of coronavirus disease-2019 (COVID-19) pneumonia in various setups, with various modes of oxygen therapy and its optimal duration. Materials and methods: A systematic literature search was conducted from inception until May 15, 2021. Patients with a validated diagnosis of COVID-19 and receiving PP were included. Various factors, including intensive care unit (ICU) or non-ICU setup, mode of oxygen therapy, outcome, duration of proning, and limitations, were noted. Results: We retrieved 36 articles with a total of 1,385 patients for qualitative analysis. Out of 36 articles, there were 17 original articles, 09 case series, and 10 case reports. Out of 1,385 participants, 78.9% (n = 1,093) and 21.0% (n = 292) of patients were managed in ICU and non-ICU setup, respectively. Awake PP with high flow nasal cannula (HFNC) was found to be a promising technique; however, the result was inconclusive with helmet continuous positive airway pressure (CPAP). No study has evaluated the optimal duration of awake PP and the associated long-term outcomes. Conclusion: We encourage the use of early awake self-proning in the management of COVID19 disease. However, the evidence in terms of its use in non-ICU setup, the optimal duration of PP, and various oxygenation devices are insufficient, thereby mandating further well-designed multicentric studies to evaluate its efficacy as an adjunct in the management of COVID-19 pneumonia in context to the aforementioned factor. How to cite this article: Chilkoti GT, Mohta M, Saxena AK, Ahmad Z, Sharma CS. Awake Prone Positioning in the Management of COVID-19 Pneumonia: A Systematic Review. Indian J Crit Care Med 2021;25(8):896-905.

COVID-19 and obesity: the meeting of two pandemics

COVID-19 and obesity are two pandemic diseases that the world is currently facing. Both activate the immune system and mediate inflammation. A sequence of disease phases in patients with severe COVID-19 results in a cytokine storm, which amplifies the subclinical inflammation that already exists in patients with obesity. Pro-inflammatory cytokines and chemotactic factors increase insulin resistance in obesity. Therefore, a greater systemic inflammatory response is establishe, along with an increased risk of thrombotic phenomena and hyperglycemic conditions. These changes further impair pulmonary, cardiac, hepatic, and renal functions, in addition to hindering glycemic control in people with diabetes and pre-diabetes. This review explains the pathophysiological mechanisms of these two pandemic diseases, provides a deeper understanding of this harmful interaction and lists possible therapeutic strategies for this risk group.

A General Overview on the Hyperbaric Oxygen Therapy: Applications, Mechanisms and Translational Opportunities

Hyperbaric oxygen therapy (HBOT) consists of using of pure oxygen at increased pressure (in general, 2-3 atmospheres) leading to augmented oxygen levels in the blood (Hyperoxemia) and tissue (Hyperoxia). The increased pressure and oxygen bioavailability might be related to a plethora of applications, particularly in hypoxic regions, also exerting antimicrobial, immunomodulatory and angiogenic properties, among others. In this review, we will discuss in detail the physiological relevance of oxygen and the therapeutical basis of HBOT, collecting current indications and underlying mechanisms. Furthermore, potential areas of research will also be examined, including inflammatory and systemic maladies, COVID-19 and cancer. Finally, the adverse effects and contraindications associated with this therapy and future directions of research will be considered. Overall, we encourage further research in this field to extend the possible uses of this procedure. The inclusion of HBOT in future clinical research could be an additional support in the clinical management of multiple pathologies.

Effects of prone positioning during extracorporeal membrane oxygenation for refractory respiratory failure: a systematic review

As more and more studies have shown that venovenous extracorporeal membrane oxygenation (VV-ECMO) improves oxygenation and prognosis of critical patients, VV-ECMO has been frequently used in critical patients for severe acute respiratory distress syndrome (ARDS). Prone positioning (PP) is a postural therapy for ARDS, which permits for better ventilation/perfusion ratio (V/Q) matching, improvement of hypoxemia. Some articles revealed that performing PP during ECMO for refractory respiratory failure is feasible; however, the results obtained were controversial. Therefore, we performed a systematic review to further assess the effects of PP during ECMO for refractory respiratory failure. Six studies with 465 subjects were enrolled. Four articles examined changes of PaO2/FiO2 ratio after PP during VV-ECMO; PaO2/FiO2 ratio improved from 18.5 to 62 mmHg. Our analysis inferred that the PP-ECMO group did not have a significant advantage in survival at discharge (odds risk 1.42, 95% confidence interval 0.92–2.18; p = 0.11) compared with the ECMO group. We found that the PP-ECMO group had a significantly longer duration than the ECMO group (MD 5.37, 95% CI 4.19–6.54, I² = 67%, P < .00001). ICU length of stay in the PP-ECMO group was significantly longer than the ECMO group (MD 7.29, 95% CI 4.06–10.52, I² = 64%, P < .00001). No unplanned extubation of ECMO was recorded. In conclusion, our review found that performing PP during ECMO for refractory respiratory failure is safe and PP can improve the PaO2/FiO2 ratio, which is in line with the length of PP performed.

SARS-CoV-2 Infection in the Central and Peripheral Nervous System-Associated Morbidities and Their Potential Mechanism

The recent outbreak of SARS-CoV-2 infections that causes coronavirus-induced disease of 2019 (COVID-19) is the defining and unprecedented global health crisis of our time in both the scale and magnitude. Although the respiratory tract is the primary target of SARS-CoV-2, accumulating evidence suggests that the virus may also invade both the central nervous system (CNS) and the peripheral nervous system (PNS) leading to numerous neurological issues including some serious complications such as seizures, encephalitis, and loss of consciousness. Here, we present a comprehensive review of the currently known role of SARS-CoV-2 and identify all the neurological problems reported among the COVID-19 case reports throughout the world. The virus might gain entry into the CNS either through the trans-synaptic route via the olfactory neurons or through the damaged endothelium in the brain microvasculature using the ACE2 receptor potentiated by neuropilin-1 (NRP-1). The most critical of all symptoms appear to be the spontaneous loss of breathing in some COVID-19 patients. This might be indicative of a dysfunction within the cardiopulmonary regulatory centers in the brainstem. These pioneering studies, thus, lay a strong foundation for more in-depth basic and clinical research required to confirm the role of SARS-CoV-2 infection in neurodegeneration of critical brain regulatory centers.

Toracostomía con colocación de tubo torácico en decúbito prono durante la pandemia de COVID-19

El síndrome respiratorio agudo severo causado por el coronavirus SARS-CoV-2 lleva a padecer insuficiencia respiratoria e hipoxemia grave y requiere la implementación de ventilación mecánica invasiva, además de estrategias como la posición en decúbito prono para mejorar la oxigenación arterial. Las complicaciones extrapulmonares como neumotórax espontáneo, neumomediastino o derrame pleural complican su manejo, en especial en posición de decúbito prono. La toracostomía con colocación de sonda pleural es el tratamiento de primera línea; este procedimiento conlleva un riesgo elevado de contagio por la generación de aerosoles, además del riesgo de lesión pulmonar durante la inserción del drenaje pleural debido a la posición en decúbito prono. Informamos un caso de infección por SARS-CoV-2 con asistencia ventilatoria mecánica complicada con neumotórax espontáneo que requirió colocar drenaje pleural cuando el paciente se encontraba en posición de decúbito prono. Describimos la técnica, que no se encuentra descrita en la literatura.

Investigating the Potential for Ultraviolet Light to Modulate Morbidity and Mortality From COVID-19: A Narrative Review and Update

During the COVID-19 (coronavirus disease of 2019) pandemic, researchers have been seeking low-cost and accessible means of providing protection from its harms, particularly for at-risk individuals such as those with cardiovascular disease, diabetes and obesity. One possible way is via safe sun exposure, and/or dietary supplementation with induced beneficial mediators (e.g., vitamin D). In this narrative review, we provide rationale and updated evidence on the potential benefits and harms of sun exposure and ultraviolet (UV) light that may impact COVID-19. We review recent studies that provide new evidence for any benefits (or otherwise) of UV light, sun exposure, and the induced mediators, vitamin D and nitric oxide, and their potential to modulate morbidity and mortality induced by infection with SARS-CoV-2 (severe acute respiratory disease coronavirus-2). We identified substantial interest in this research area, with many commentaries and reviews already published; however, most of these have focused on vitamin D, with less consideration of UV light (or sun exposure) or other mediators such as nitric oxide. Data collected to-date suggest that ambient levels of both UVA and UVB may be beneficial for reducing severity or mortality due to COVID-19, with some inconsistent findings. Currently unresolved are the nature of the associations between blood 25-hydroxyvitamin D and COVID-19 measures, with more prospective data needed that better consider lifestyle factors, such as physical activity and personal sun exposure levels. Another short-coming has been a lack of measurement of sun exposure, and its potential to influence COVID-19 outcomes. We also discuss possible mechanisms by which sun exposure, UV light and induced mediators could affect COVID-19 morbidity and mortality, by focusing on likely effects on viral pathogenesis, immunity and inflammation, and potential cardiometabolic protective mechanisms. Finally, we explore potential issues including the impacts of exposure to high dose UV radiation on COVID-19 and vaccination, and effective and safe doses for vitamin D supplementation.

Imaging Review of Peripheral Nerve Injuries in Patients with COVID-19

With surging numbers of patients with coronavirus disease 2019 (COVID-19) throughout the world, neuromuscular complications and rehabilitation concerns are becoming more apparent. Peripheral nerve injury can occur in patients with COVID-19 secondary to postinfectious inflammatory neuropathy, prone positioning-related stretch and/or compression injury, systemic neuropathy, or nerve entrapment from hematoma. Imaging of peripheral nerves in patients with COVID-19 may help to characterize nerve abnormality, to identify site and severity of nerve damage, and to potentially elucidate mechanisms of injury, thereby aiding the medical diagnosis and decision-making process. This review article aims to provide a first comprehensive summary of the current knowledge of COVID-19 and peripheral nerve imaging.

Using the prone position could help to combat the development of fast hypoxia in some patients with COVID-19

The world is facing an explosive COVID‐19 pandemic. Some cases rapidly develop deteriorating lung function, which causes deep hypoxaemia and requires urgent treatment. Many centres have started treating patients in the prone position, and oxygenation has improved considerably in some cases. Questions have been raised regarding the mechanisms behind this. The mini review provides some insights into the role of supine and prone body positions and summarises the latest understanding of the responsible mechanisms. The scope for discussion is outside the neonatal period and entirely based on experimental and clinical experiences related to adults. The human respiratory system is a complex interplay of many different variables. Therefore, this mini review has prioritised previous and ongoing research to find explanations based on three scientific areas: gravity, lung structure and fractal geometry and vascular regulation. It concludes that gravity is one of the variables responsible for ventilation/perfusion matching but in concert with lung structure and fractal geometry, ventilation and regulation of lung vascular tone. Since ventilation distribution does not change between supine and prone positions, the higher expression of nitric oxide in dorsal lung vessels than in ventral vessels is likely to be the most important mechanism behind enhanced oxygenation in the prone position.