scholarly journals The Fundamentals of Respiratory Physiology to Manage the COVID-19 Pandemic: An Overview

2021 ◽  
Vol 11 ◽  
Author(s):  
Edem Allado ◽  
Mathias Poussel ◽  
Simon Valentin ◽  
Antoine Kimmoun ◽  
Bruno Levy ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Distress Syndrome ◽  
Oxygen Affinity ◽  
Ventilator Weaning ◽  
Respiratory Physiology ◽  
Arterial Oxygenation ◽  
Sharp Rise ◽  
Critical Situation ◽  
High Altitude Pulmonary Edema ◽  
Hemoglobin Oxygen Affinity

The growing coronavirus disease (COVID-19) crisis has stressed worldwide healthcare systems probably as never before, requiring a tremendous increase of the capacity of intensive care units to handle the sharp rise of patients in critical situation. Since the dominant respiratory feature of COVID-19 is worsening arterial hypoxemia, eventually leading to acute respiratory distress syndrome (ARDS) promptly needing mechanical ventilation, a systematic recourse to intubation of every hypoxemic patient may be difficult to sustain in such peculiar context and may not be deemed appropriate for all patients. Then, it is essential that caregivers have a solid knowledge of physiological principles to properly interpret arterial oxygenation, to intubate at the satisfactory moment, to adequately manage mechanical ventilation, and, finally, to initiate ventilator weaning, as safely and as expeditiously as possible, in order to make it available for the next patient. Through the expected mechanisms of COVID-19-induced hypoxemia, as well as the notion of silent hypoxemia often evoked in COVID-19 lung injury and its potential parallelism with high altitude pulmonary edema, from the description of hemoglobin oxygen affinity in patients with severe COVID-19 to the interest of the prone positioning in order to treat severe ARDS patients, this review aims to help caregivers from any specialty to handle respiratory support following recent knowledge in the pathophysiology of respiratory SARS-CoV-2 infection.

Mechanical Ventilation: Respiratory Physiology and Conventional Ventilation

2018 ◽  
Author(s):  
Adrian A. Maung ◽  
Lewis J Kaplan
Keyword(s):  
Mechanical Ventilation ◽  
Respiratory Failure ◽  
Distress Syndrome ◽  
Functional Unit ◽  
Respiratory Physiology ◽  
Pulmonary Physiology ◽  
Functional Understanding ◽  
Ground Ambulance ◽  
Prerequisite Knowledge ◽  
Ventilation Modes

This three-part review is intended to enable the reader to manage the fundamentals of mechanical ventilation in both the urgent and the nonurgent setting. This first chapter provides a functional understanding of basic pulmonary physiology as a prerequisite knowledge base prior to reviewing the concepts central to basic, traditional, and cyclical ventilation that is regularly employed in the air or ground ambulance, emergency department, operating room, and intensive care unit. Subsequent chapters will review advanced ventilation modes, adjuncts, and special problems encountered in patients with respiratory failure requiring mechanical ventilation. Each segment is intended to build on the preceding one and therefore establishes a functional unit with regard to mechanical ventilation, whether it is provided in an invasive or a noninvasive fashion.   This review contains 5 Figures and 10 references Key Words: acute respiratory failure, acute respiratory distress syndrome, hypercapnia/therapy, hypoxia/therapy, mechanical ventilation, pulmonary gas exchange

scholarly journals Spontaneous pneumothorax, with or without pulmonary cysts, in patients with COVID-19 pneumonia

2021 ◽  
Vol 15 (10) ◽  
pp. 1404-1407
Author(s):  
Javier Leonardo Galindo ◽  
Luisa Fernanda Jiménez ◽  
Juan Ricardo Lutz ◽  
María Alejandra Izquierdo ◽  
Viviana Lucía Rivillas ◽  
...  
Keyword(s):  
Mechanical Ventilation ◽  
Medical Records ◽  
Spontaneous Pneumothorax ◽  
Distress Syndrome ◽  
Invasive Mechanical Ventilation ◽  
Ventilator Weaning ◽  
Radiologic Findings ◽  
Pulmonary Cysts ◽  
Rare Manifestation

Introduction: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) affects mainly the lungs causing pneumonia and complications like acute respiratory distress syndrome. Pneumothorax is a rare manifestation of the disease. This report is a description of a series of patients with COVID-19 and spontaneous pneumothorax, some of them with associated pulmonary cysts. Methodology: Cases were collected retrospectively. We included clinical data from medical records and described radiologic findings. Patients that developed pneumothorax during mechanical ventilation were excluded. Results: Ten cases were included in this report, nine of them were male. The median age of our series was 62 years (IQR = 57-68). The median days since the onset of symptoms until the development of pneumothorax was 27 (IQR = 17-31), most cases developed after the second week of the diagnosis of pneumonia. Two cases required invasive mechanical ventilation, but pneumothorax occurred after ventilator weaning. Three cases showed subpleural pulmonary cysts. Conclusions: Cysts and pneumothorax are rare manifestations of SARS-CoV-2 pneumonia with mechanisms not completely understood. This report highlights the role of CT scan in diagnosis of COVID-19 complications.

The ventilated patient

2010 ◽  
pp. 133-148
Author(s):  
George Samandouras
Keyword(s):  
Mechanical Ventilation ◽  
Oxygen Therapy ◽  
Ventilator Weaning ◽  
Respiratory Physiology ◽  
Ventilator Settings

Chapter 3.4, The Ventilated Patient, covers clinical respiratory physiology, oxygen therapy, abnormal respiratory patterns, mechanical ventilation, ventilators, ventilator settings, setting up a ventilator, complications of ventilation, and ventilator weaning.

Mechanical Ventilation: Respiratory Physiology and Conventional Ventilation

2018 ◽  
Author(s):  
Adrian A. Maung ◽  
Lewis J Kaplan
Keyword(s):  
Mechanical Ventilation ◽  
Respiratory Failure ◽  
Distress Syndrome ◽  
Functional Unit ◽  
Respiratory Physiology ◽  
Pulmonary Physiology ◽  
Functional Understanding ◽  
Ground Ambulance ◽  
Prerequisite Knowledge ◽  
Ventilation Modes

This three-part review is intended to enable the reader to manage the fundamentals of mechanical ventilation in both the urgent and the nonurgent setting. This first chapter provides a functional understanding of basic pulmonary physiology as a prerequisite knowledge base prior to reviewing the concepts central to basic, traditional, and cyclical ventilation that is regularly employed in the air or ground ambulance, emergency department, operating room, and intensive care unit. Subsequent chapters will review advanced ventilation modes, adjuncts, and special problems encountered in patients with respiratory failure requiring mechanical ventilation. Each segment is intended to build on the preceding one and therefore establishes a functional unit with regard to mechanical ventilation, whether it is provided in an invasive or a noninvasive fashion.   This review contains 5 Figures and 10 references Key Words: acute respiratory failure, acute respiratory distress syndrome, hypercapnia/therapy, hypoxia/therapy, mechanical ventilation, pulmonary gas exchange

Prone positioning in the ICU

2016 ◽  
Author(s):  
Paolo Taccone ◽  
Davide Chiumello
Keyword(s):  
Mechanical Ventilation ◽  
Gas Exchange ◽  
Pulmonary Blood Flow ◽  
Distress Syndrome ◽  
Patient Survival ◽  
Physiological Effect ◽  
Arterial Oxygenation ◽  
Prone Positioning ◽  
Recumbent Position ◽  
Physiological Research

Prone positioning (also known as ‘proning’, ‘prone manoeuvre’ or ‘prone ventilation’) refers to mechanical ventilation with patients positioned in prone position in contrast of standard supine (flat or semi-recumbent) position. The use of the prone positioning was proposed over 30 years ago as a means to improve arterial oxygenation in patients with acute respiratory distress syndrome (ARDS). Since then, extensive physiological research has been conducted to explore the possible mechanisms underlying the observed improvement in gas exchange, which involve changes in the distribution of both ventilation and pulmonary blood flow. Furthermore, it has been shown that, independently of gas exchange, prone positioning may reduce the harm of mechanical ventilation, which is known to adversely impact patient survival. In this chapter we will summarize the physiological effect of prone positioning, as well as the clinical evidences supporting its use to reduce mortality in patients with ARDS.

scholarly journals Proning related bilateral anterior ischaemic optic neuropathy in a patient with COVID-19 related acute respiratory distress syndrome

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Kirsty Michelle Clarke ◽  
Vivi Riga ◽  
Amy-lee Shirodkar ◽  
Joel Meyer
Keyword(s):  
Mechanical Ventilation ◽  
Acute Respiratory Distress Syndrome ◽  
Visual Field ◽  
Respiratory Distress Syndrome ◽  
Distress Syndrome ◽  
Vision Loss ◽  
Prone Positioning ◽  
Disc Oedema ◽  
Ischaemic Optic Neuropathy ◽  
The Right

Abstract Background Non-arteritic ischaemic optic neuropathy (NAION) is a rare but harmful complication of prone positioning. Prone mechanical ventilation is a therapeutic strategy which has been used extensively during the COVID-19 pandemic to treat acutely hypoxemic patients with COVID-19 related acute respiratory distress syndrome (ARDS). Though a small number of cases of unilateral NAION have been reported in patients testing positive for the SARS-CoV-2 virus, we describe what is to our knowledge, the first reported case of bilateral NAION occurring in a patient proned extensively for the treatment of COVID-19 related ARDS. We consider the potential aetiological factors leading to NAION after prone mechanical ventilation in patients with COVID-19 and suggest strategies to protect against its development. Case presentation : We report a case of severe, irreversible, visual impairment secondary to bilateral anterior ION in a fifty-five-year-old male who underwent eight episodes of prone mechanical ventilation to treat COVID-19 related ARDS. Once weaned from his sedation he reported bilateral painless vision loss, and bedside ophthalmological assessment identified a reduced visual acuity of 3/30 unaided in the left eye and counting fingers in the right. Dilated indirect ophthalmoscopy revealed inferotemporal optic disc oedema with splinter haemorrhages in the right eye and mild disc oedema, temporal pallor, and nerve fibre layer haemorrhages inferiorly in the left eye. Humphrey visual field 24 − 2 testing confirmed a severely constricted visual field with macular sparing on the right and depressed inferonasal vision with preserved peripheral vision on the left eye. OCT disc imaging shortly after diagnosis revealed bilateral disc swelling and flame haemorrhages in the right eye. Conclusions NAION is a devastating, but preventable complication of prone positioning, which may pose significant risk of vision loss in patients with COVID-19 related ARDS.

scholarly journals Molecular Pathways Involved in the Development of Congenital Erythrocytosis

Genes ◽  
2021 ◽  
Vol 12 (8) ◽  
pp. 1150
Author(s):  
Jana Tomc ◽  
Nataša Debeljak
Keyword(s):  
Signal Transduction ◽  
Iron Homeostasis ◽  
Molecular Mechanisms ◽  
Oxygen Affinity ◽  
Molecular Pathways ◽  
Disease Development ◽  
Post Translational Modifications ◽  
Hemoglobin Oxygen Affinity ◽  
Insight Into ◽  
Idiopathic Erythrocytosis

Patients with idiopathic erythrocytosis are directed to targeted genetic testing including nine genes involved in oxygen sensing pathway in kidneys, erythropoietin signal transduction in pre-erythrocytes and hemoglobin-oxygen affinity regulation in mature erythrocytes. However, in more than 60% of cases the genetic cause remains undiagnosed, suggesting that other genes and mechanisms must be involved in the disease development. This review aims to explore additional molecular mechanisms in recognized erythrocytosis pathways and propose new pathways associated with this rare hematological disorder. For this purpose, a comprehensive review of the literature was performed and different in silico tools were used. We identified genes involved in several mechanisms and molecular pathways, including mRNA transcriptional regulation, post-translational modifications, membrane transport, regulation of signal transduction, glucose metabolism and iron homeostasis, which have the potential to influence the main erythrocytosis-associated pathways. We provide valuable theoretical information for deeper insight into possible mechanisms of disease development. This information can be also helpful to improve the current diagnostic solutions for patients with idiopathic erythrocytosis.

scholarly journals Non-invasive duo positive airway pressure ventilation versus nasal continuous positive airway pressure in preterm infants with respiratory distress syndrome: a randomized controlled trial

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Arash Malakian ◽  
Mohammad Reza Aramesh ◽  
Mina Agahin ◽  
Masoud Dehdashtian
Keyword(s):  
Mechanical Ventilation ◽  
Continuous Positive Airway Pressure ◽  
Respiratory Distress Syndrome ◽  
Respiratory Distress ◽  
Airway Pressure ◽  
Distress Syndrome ◽  
Positive Airway Pressure ◽  
Invasive Ventilation ◽  
Non Invasive ◽  
Non Invasive Ventilation

Abstract Background The most common cause of respiratory failure in premature infants is respiratory distress syndrome. Historically, respiratory distress syndrome has been treated by intratracheal surfactant injection followed by mechanical ventilation. In view of the risk of pulmonary injury associated with mechanical ventilation and subsequent chronic pulmonary lung disease, less invasive treatment modalities have been suggested to reduce pulmonary complications. Methods 148 neonates (with gestational age of 28 to 34 weeks) with respiratory distress syndrome admitted to Imam Khomeini Hospital in Ahwaz in 2018 were enrolled in this clinical trial study. 74 neonates were assigned to duo positive airway pressure (NDUOPAP) group and 74 neonates to nasal continuous positive airway pressure (NCPAP) group. The primary outcome in this study was failure of N-DUOPAP and NCPAP treatments within the first 72 h after birth and secondary outcomes included treatment complications. Results there was not significant difference between DUOPAP (4.1 %) and NCPAP (8.1 %) in treatment failure at the first 72 h of birth (p = 0.494), but non-invasive ventilation time was less in the DUOPAP group (p = 0.004). There were not significant differences in the frequency of patent ductus arteriosus (PDA), pneumothorax, intraventricular hemorrhage (IVH) and bronchopulmonary dysplasia (BPD), apnea and mortality between the two groups. Need for repeated doses of surfactant (p = 0.042) in the NDUOPAP group was significantly lower than that of the NCPAP group. The duration of oxygen therapy in the NDUOPAP group was significantly lower than that of the NCPAP group (p = 0.034). Also, the duration of hospitalization in the NDUOPAP group was shorter than that of the NCPAP group (p = 0.002). Conclusions In the present study, DUOPAP compared to NCPAP did not reduce the need for mechanical ventilation during the first 72 h of birth, but the duration of non-invasive ventilation and oxygen demand, the need for multiple doses of surfactant and length of stay in the DUOPAP group were less than those in the CPAP group. Trial registration IRCT20180821040847N1, Approved on 2018-09-10.

Sign in / Sign up

Export Citation Format

Share Document