From the ventilation perspective, lung parenchyma is commonly treated as an isotropic, homogeneous elastic continuum. Nevertheless, this assumption may often be an impediment to a better understanding of the problem of ventilation/perfusion mismatch causing hypoxemia in lung disease as the heterogeneity of gas distribution is often neglected in the study of lung function. Unilateral lung disease such as unilateral pulmonary edema, lobar pneumonia or pneumothorax are common examples of acute asymmetric lung pathologies, but chronic conditions such as emphysema or interstitial lung disease can present this way and lead to a gross heterogeneity of ventilation distribution. The heterogeneity of lung ventilation is a phenomenon that exists on a more subtle level within the lung segments and studies suggest that ventilation heterogeneity characterizes conditions such as asthma or COPD and may be regionally identified and visualized using pulmonary imaging methods such as gas magnetic resonance imaging , or by the multiple-breath nitrogen washout (MBNW). In the acute respiratory distress syndrome (ARDS) is characterized by inadequate distribution of ventilation with a relatively small number of normal alveoli receiving most of the tidal volume, a phenomenon that promotes high cyclic stress concentrated in a few lung units, probably triggering further parenchymal injury.
In the setting of conditions such as ARDS, mechanical, positive-pressure ventilation may augment the impact of heterogeneity of gas distribution on a tissue injury: in an injured inhomogeneous lung parenchyma, the strain of tissues is unevenly distributed with localized increase of stress and a transpulmonary pressure that is safe in a homogeneous lung, if multiplied sufficiently by regional stress raisers, may locally reach harmful levels for the lung structure. The lung inhomogeneities increased with ARDS severity, is positively associated with dead space fraction and poorly aerated tissue, decreases when PEEP is increased, and is independently associated with clinical outcomes. The impact of heterogeneity has become even more obvious in recent COVID-19 pandemic in patients suffering from severe ARDS where the prone ventilation has been recommended as one of the key interventions in its management. The estimate of the lung inhomogeneity may open possible new scenarios in understanding the complex interaction between ventilation-induced lung injury, positive end-expiratory pressure (PEEP), and mechanical ventilation.
A Research Topic in Frontiers in Medical Technology focused on the new advancements in the understanding of the significance, diagnosis and management of lung ventilation heterogeneity may be a timely, novel and intriguing project. The goal is to bring together a collection of papers that cover novel physiologic, diagnostic, and therapeutic approaches addressing the heterogeneity of lung ventilation.
We welcome the submission of manuscripts focused on the lung ventilation heterogeneity. These may include original review, case series, mini reports or comprehensive reviews addressing the problem from the angle of various specialties including physics, physiology, pulmonary medicine, critical care, anesthesiology, radiology, pathology, or genetics. In particular:
- Observational studies using primary or secondary data aimed at:
(1) Identifying risk factors associated with lung ventilation heterogeneity
(2) Quantifying the risk of mechanical ventilation, asthma, and COPD in patients with recognized lung ventilation heterogeneity
-Scoping reviews or systematic reviews aimed at assessing:
(1) The epidemiology (prevalence, incidence, burden of illness) of lung ventilation heterogeneity across different population and settings
In order to address the following questions:
- What defines ventilation heterogeneity? What are clinical differences between regional vs. between-lungs heterogeneity?
- What is the impact of lung heterogeneity on normal individuals and how does it relate to the lung disease, both chronic acute and chronic?
- Are there novel diagnostic methods to better understand lung heterogeneity?
- Are there any novel therapeutic approaches and concepts in addressing the problem of lung ventilation heterogeneity?
- What is the impact of lung ventilation heterogeneity in mechanical ventilation?
- Are there any new pathobiological insights generated by the models of mechanical ventilation in heterogeneous lung injury?
From the ventilation perspective, lung parenchyma is commonly treated as an isotropic, homogeneous elastic continuum. Nevertheless, this assumption may often be an impediment to a better understanding of the problem of ventilation/perfusion mismatch causing hypoxemia in lung disease as the heterogeneity of gas distribution is often neglected in the study of lung function. Unilateral lung disease such as unilateral pulmonary edema, lobar pneumonia or pneumothorax are common examples of acute asymmetric lung pathologies, but chronic conditions such as emphysema or interstitial lung disease can present this way and lead to a gross heterogeneity of ventilation distribution. The heterogeneity of lung ventilation is a phenomenon that exists on a more subtle level within the lung segments and studies suggest that ventilation heterogeneity characterizes conditions such as asthma or COPD and may be regionally identified and visualized using pulmonary imaging methods such as gas magnetic resonance imaging , or by the multiple-breath nitrogen washout (MBNW). In the acute respiratory distress syndrome (ARDS) is characterized by inadequate distribution of ventilation with a relatively small number of normal alveoli receiving most of the tidal volume, a phenomenon that promotes high cyclic stress concentrated in a few lung units, probably triggering further parenchymal injury.
In the setting of conditions such as ARDS, mechanical, positive-pressure ventilation may augment the impact of heterogeneity of gas distribution on a tissue injury: in an injured inhomogeneous lung parenchyma, the strain of tissues is unevenly distributed with localized increase of stress and a transpulmonary pressure that is safe in a homogeneous lung, if multiplied sufficiently by regional stress raisers, may locally reach harmful levels for the lung structure. The lung inhomogeneities increased with ARDS severity, is positively associated with dead space fraction and poorly aerated tissue, decreases when PEEP is increased, and is independently associated with clinical outcomes. The impact of heterogeneity has become even more obvious in recent COVID-19 pandemic in patients suffering from severe ARDS where the prone ventilation has been recommended as one of the key interventions in its management. The estimate of the lung inhomogeneity may open possible new scenarios in understanding the complex interaction between ventilation-induced lung injury, positive end-expiratory pressure (PEEP), and mechanical ventilation.
A Research Topic in Frontiers in Medical Technology focused on the new advancements in the understanding of the significance, diagnosis and management of lung ventilation heterogeneity may be a timely, novel and intriguing project. The goal is to bring together a collection of papers that cover novel physiologic, diagnostic, and therapeutic approaches addressing the heterogeneity of lung ventilation.
We welcome the submission of manuscripts focused on the lung ventilation heterogeneity. These may include original review, case series, mini reports or comprehensive reviews addressing the problem from the angle of various specialties including physics, physiology, pulmonary medicine, critical care, anesthesiology, radiology, pathology, or genetics. In particular:
- Observational studies using primary or secondary data aimed at:
(1) Identifying risk factors associated with lung ventilation heterogeneity
(2) Quantifying the risk of mechanical ventilation, asthma, and COPD in patients with recognized lung ventilation heterogeneity
-Scoping reviews or systematic reviews aimed at assessing:
(1) The epidemiology (prevalence, incidence, burden of illness) of lung ventilation heterogeneity across different population and settings
In order to address the following questions:
- What defines ventilation heterogeneity? What are clinical differences between regional vs. between-lungs heterogeneity?
- What is the impact of lung heterogeneity on normal individuals and how does it relate to the lung disease, both chronic acute and chronic?
- Are there novel diagnostic methods to better understand lung heterogeneity?
- Are there any novel therapeutic approaches and concepts in addressing the problem of lung ventilation heterogeneity?
- What is the impact of lung ventilation heterogeneity in mechanical ventilation?
- Are there any new pathobiological insights generated by the models of mechanical ventilation in heterogeneous lung injury?