暂无摘要。

Acute respiratory distress syndrome (ARDS) caused by coronavirus disease (COVID-19) is a serious complication that requires early recognition. Autopsy reports or biopsies of the lungs in patients with COVID-19 revealed diffuse alveolar damage (DAD) at different stages; the fibrotic phase is usually associated with long-standing severe disease. Care management of hospitalized patients is not easy, given that the risk of incurring a ventilator-induced lung injury (VILI) is high. Additionally, if the patient develops nosocomial infections, sepsis-induced ARDS should be considered in the study of the pathophysiological processes. We present an autopsy case of a hospitalized patient whose death was linked to COVID-19 infection, with the histopathological pattern of advanced pulmonary fibrosis. After prolonged use of non-invasive and invasive ventilation, the patient developed polymicrobial superinfection oh the lungs. After analyzing the individual\'s clinical history and pulmonary anatomopathological findings, we consider healthcare issues that should lead to an improvement in diagnosis and to more adequate standards of care management among health professionals.

Lung involvement with differing phenotypes characterizes COVID-19-induced acute respiratory distress syndrome (CARDS). The liberation of these patients from mechanical ventilation has been challenging. Excessive stress and strain following increased respiratory efforts spiral their vulnerable lung tissue into ventilator-induced lung injury vortex. The use of high-flow oxygen therapy via tracheostomy (HFOTTracheal)eases weaning process. As a safe option for both the patient and the healthcare workers, HFOTTracheal was successfully employed to wean two CARDS patients from the mechanical ventilator. How to cite this article: Vadi S, Phadtare S, Shetty K. High-flow Oxygen Therapy via Tracheostomy to Liberate COVID-19-induced ARDS from Invasive Ventilation: A Case Series. Indian J Crit Care Med 2021;25(6):724-728.

Coronavirus disease (COVID-19) started in Wuhan (China) at the end of 2019, and then increased rapidly. In patients with severe acute respiratory distress syndrome (ARDS) caused by COVID-19, venovenous extracorporeal membrane oxygenation (VV-ECMO) is considered a rescue therapy that provides adequate gas exchange. The way in which mechanical ventilation is applied during VV-ECMO is not clear, however it is associated with prognosis. Currently, the mortality rate of COVID-19 patients that receive VV-ECMO stands at approximately 50%. Here, we report three patients that successfully recovered from COVID-19-induced ARDS after VV-ECMO and implementation of an ultra-protective ventilation. This ventilation strategy involved maintaining a peak inspiratory pressure of ≤20 cmH2O and a positive end-expiratory pressure (PEEP) of ≤ 10 cmH2O, which are lower values than have been previously reported. Thus, we suggest that this ultra-protective ventilation be considered during VV-ECMO as it minimizes the ventilator-induced lung injury.

BACKGROUND COVID-19 patients that develop acute respiratory distress syndrome (ARDS) \"CARDS\" behave differently compared to patients with classic forms of ARDS. Recently 2 CARDS phenotypes have been described, Type L and Type H. Most patients stabilize at the milder form, Type L, while an unknown subset progress to Type H, resembling full-blown ARDS. If uncorrected, phenotypic conversion can induce a rapid downward spiral towards progressive lung injury, vasoplegia, and pulmonary shrinkage, risking ventilator-induced lung injury (VILI) known as the \"VILI vortex\". No cases of in-hospital phenotypic conversion have been reported, while ventilation strategies in these patients differ from the lung-protective approaches seen in classic ARDS. CASE REPORT A 29-year old male was admitted with COVID-19 pneumonia complicated by severe ARDS, multi-organ failure, cytokine release syndrome, and coagulopathy during his admission. He initially resembled CARDS Type L case, although refractory hypoxemia, fevers, and a high viral burden prompted conversion to Type H within 8 days. Despite ventilation strategies, neuromuscular blockade, inhalation therapy, and vitamin C, he remained asynchronous to the ventilator with volumes and pressures beyond accepted thresholds, eventually developing a fatal tension pneumothorax. CONCLUSIONS Patients that convert to Type H can quickly enter a spiral of hypoxemia, shunting, and dead-space ventilation towards full-blown ARDS. Understanding its nuances is vital to interrupting phenotypic conversion and entry into VILI vortex. Tension pneumothorax represents a poor outcome in patients with CARDS. Further research into monitoring lung dynamics, modifying ventilation strategies, and understanding response to various modes of ventilation in CARDS are required to mitigate these adverse outcomes.

UNASSIGNED: Prone positioning may provide a uniform distribution of transpulmonary pressure and contribute to prevent ventilator-induced lung injury. However, despite moderate positive end-expiratory pressure and low tidal volumes, there is still a risk of regional overdistension.
UNASSIGNED: A man with refractory hypoxemia was mechanically ventilated with prone positioning. Although prone positioning with a plateau pressure of 18 cmH2O and a positive end-expiratory pressure of 8 cmH2O promptly improved oxygenation, regional ventilation monitoring using electrical impedance tomography initially detected decreased distribution in the dorsal region but increased in the ventral, suggesting overdistension.
UNASSIGNED: Our experience indicates monitoring regional ventilation distribution is useful for decreasing the risk of overdistension during prone positioning.

BACKGROUND: Mechanical ventilation of severe acute asthma is still considered a challenging issue, mainly because of the gas trapping phenomenon with the potential for life-threatening barotraumatic pulmonary complications.
UNASSIGNED: Herein, we describe 2 consecutive cases of near-fatal asthma for whom the recommended protective mechanical ventilation approach using low tidal volume of 6 mL/kg and small levels of PEEP was rapidly compromised by giant pneumomediastinum with extensive subcutaneousemphysema.
UNASSIGNED: Near fatal asthma.
METHODS: A rescue therapeutic strategy combining extracorporeal CO2 removal membrane with ultra-protective extremely low tidal volume (3 mL/kg) ventilation was applied.
RESULTS: Both patients survived hospital discharge.
CONCLUSIONS: These 2 cases indicate that ECCO2R associated with ultra-protective ventilation could be an alternative to surgery in case of life-threatening barotrauma occurring under mechanical ventilation.

BACKGROUND: Pulmonary infections caused by Pneumocystis jirovecii in immunocompromised host can be associated with cysts, pneumatoceles and air leaks that can progress to pneumomediastinum and pneumothoraxes. In such cases, it can be challenging to maintain adequate gas exchange by conventional mechanical ventilation and at the same time prevent further ventilator-induced lung injury. We report a young HIV positive male with poorly compliant lungs and pneumomediastinum secondary to severe Pneumocystis infection, rescued with veno-venous extra corporeal membrane oxygenation (V-V ECMO).
METHODS: A 26 year old male with no significant past medical history was admitted with fever, cough and shortness of breath. He initially required non-invasive ventilation for respiratory failure. However, his respiratory function progressively deteriorated due to increasing pulmonary infiltrates and development of pneumomediastinum, eventually requiring endotracheal intubation and invasive ventilation. Despite attempts at optimizing gas exchange by ventilatory maneuvers, patients\' pulmonary parameters worsened necessitating rescue ECMO therapy. The introduction of V-V ECMO facilitated the use of ultra-protective lung ventilation and prevented progression of pneumomediastinum, maintaining optimal gas exchange. It allowed time for the antibiotics to show effect and pulmonary parenchyma to heal. Further diagnostic workup revealed Pneumocystis jirovecii as the causative organism for pneumonia and serology confirmed Human Immunodeficiency Virus infection. Patient was successfully treated with appropriate antimicrobials and de-cannulated after six days of ECMO support.
CONCLUSIONS: ECMO was an effective salvage therapy in HIV positive patient with an otherwise fatal respiratory failure due to Pneumocystis pneumonia and air leak syndrome.