Results 11 to 20 of about 3,345,378 (306)

Ventilation-Perfusion Ratio in Perflubron During Partial Liquid Ventilation

Anesthesia & Analgesia, 2010
Functional magnetic resonance imaging (fMRI) of fluorine-19 allows for the mapping of oxygen partial pressure within perfluorocarbons in the alveolar space (Pao(2)). Theoretically, fMRI-detected Pao(2) can be combined with the Fick principle approach, i.e., a mass balance of oxygen uptake by ventilation and delivery by perfusion, to quantify the ...
Scholz, Alexander-Wigbert K., Eberle, Balthasar, Heussel, Claus P., David, Matthias, Schmittner, Marc D., Quintel, Michael, Schreiber, Laura Maria, Weiler, Norbert   +7 more
openaire   +5 more sources

Ventilation perfusion functional difference images in lung SPECT: A linear and symmetrical scale as an alternative to the ventilation perfusion ratio

Physica Medica
Ventilation Perfusion SPECT is important in the diagnostics of e.g. pulmonary embolism and chronic obstructive pulmonary disease. Classical and reverse mismatched defects can be identified by utilizing the ventilation-perfusion ratio. Unfortunately, this ratio is only linear in the ventilation, the scale is not symmetrical regarding classical and ...
Robin de Nijs, Ronan M.G. Berg, Sofie Lindskov Hansen, Jann Mortensen   +3 more
openaire   +5 more sources

Ventilation-perfusion ratio obtained by a noninvasive frequency response technique

Journal of Applied Physiology, 1976
Results of animal experiments using sinusoidal changes in inspired halothane concentration showed that the ratio of variation in end-expired concentration to the variation in inspired concentration reached a plateau in theBode diagram. With the help of an uptake and distribution model, the interpretation of the results showed that the level of the ...
A, Zwart, R C, Seagrave, A, Van Dieren
openaire   +3 more sources

Parametric estimation of ventilation-perfusion ratio distributions

Journal of Applied Physiology, 1983
We present a model and rigorous statistical approach for recovery of ventilation-perfusion ratio (V/Q) distribution parameters from multiple inert gas elimination data. We model the lung as a parallel combination of shunt, dead space, and one to three log-normal distributions of gas exchange units.
W E, Stewart, S M, Mastenbrook
openaire   +3 more sources

Influence of Positive End-Expiratory Pressure Titration on the Effects of Pronation in Acute Respiratory Distress Syndrome: A Comprehensive Experimental Study

Frontiers in Physiology, 2020
Prone position can reduce mortality in acute respiratory distress syndrome (ARDS), but several studies found variable effects on oxygenation and lung mechanics.
Gaetano Scaramuzzo, Gaetano Scaramuzzo, Lorenzo Ball, Lorenzo Ball, Fabio Pino, Fabio Pino, Lucia Ricci, Lucia Ricci, Anders Larsson, Claude Guérin, Claude Guérin, Claude Guérin, Paolo Pelosi, Paolo Pelosi, Gaetano Perchiazzi, Gaetano Perchiazzi   +15 more
doaj   +1 more source

Anatomy and physiology of respiratory system relevant to anaesthesia

Indian Journal of Anaesthesia, 2015
Clinical application of anatomical and physiological knowledge of respiratory system improves patient's safety during anaesthesia. It also optimises patient's ventilatory condition and airway patency.
Apeksh Patwa, Amit Shah
doaj   +1 more source

Ventilation–perfusion heterogeneity measured by the multiple inert gas elimination technique is minimally affected by intermittent breathing of 100% O2

Physiological Reports, 2020
Proton magnetic resonance (MR) imaging to quantify regional ventilation–perfusion ( V˙A/Q˙) ratios combines specific ventilation imaging (SVI) and separate proton density and perfusion measures into a composite map.
Ann R. Elliott, Abhilash S. Kizhakke Puliyakote, Vincent Tedjasaputra, Beni Pazár, Harrieth Wagner, Rui C. Sá, Jeremy E. Orr, G. Kim Prisk, Peter D. Wagner, Susan R. Hopkins   +9 more
doaj   +1 more source

Dead space ventilation-related indices: bedside tools to evaluate the ventilation and perfusion relationship in patients with acute respiratory distress syndrome

Critical Care, 2023
Cumulative evidence has demonstrated that the ventilatory ratio closely correlates with mortality in acute respiratory distress syndrome (ARDS), and a primary feature in coronavirus disease 2019 (COVID-19)-ARDS is increased dead space that has been ...
Mingjia Zheng
doaj   +1 more source

Unstable SpO2 in preterm infants: The key role of reduced ventilation to perfusion ratio

Frontiers in Physiology, 2023
Introduction: Instability of peripheral oxyhemoglobin saturation (SpO2) in preterm infants is correlated with late disability and is poorly understood.
Benjamin Stoecklin, Benjamin Stoecklin, Y. Jane Choi, Y. Jane Choi, Theodore Dassios, J. Gareth Jones, Geoffrey G. Lockwood, J. Jane Pillow, J. Jane Pillow   +8 more
doaj   +1 more source

Imaging lung function in mice using SPECT/CT and per-voxel analysis. [PDF]

PLoS ONE, 2012
Chronic lung disease is a major worldwide health concern but better tools are required to understand the underlying pathologies. Ventilation/perfusion (V/Q) single photon emission computed tomography (SPECT) with per-voxel analysis allows for non ...
Brian N Jobse, Rod G Rhem, Cory A J R McCurry, Iris Q Wang, N Renée Labiris   +4 more
doaj   +1 more source