Two challenges in the management of Acute Respiratory Distress Syndrome are the difficulty in diagnosing cyclical atelectasis, and in individualising mechanical ventilation therapy in real-time. Commercial optical oxygen sensors can detect [Formula: see text] oscillations associated with cyclical atelectasis, but are not accurate at saturation levels below 90%, and contain a toxic fluorophore. We present a computer-controlled test rig, together with an in-house constructed ultra-rapid sensor to test the limitations of these sensors when exposed to rapidly changing [Formula: see text] in blood in vitro. We tested the sensors' responses to simulated respiratory rates between 10 and 60 breaths per minute. Our sensor was able to detect the whole amplitude of the imposed [Formula: see text] oscillations, even at the highest respiratory rate. We also examined our sensor's resistance to clot formation by continuous in vivo deployment in non-heparinised flowing animal blood for 24h, after which no adsorption of organic material on the sensor's surface was detectable by scanning electron microscopy.
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http://dx.doi.org/10.1016/j.resp.2013.10.006 | DOI Listing |
Vet Parasitol Reg Stud Reports
October 2024
Instituto de Innovación para la Producción Agropecuaria y el Desarrollo Sostenible (IPADS, INTA Balcarce-CONICET), RN 226 Km 73.5, 7620 Balcarce, Buenos Aires, Argentina. Electronic address:
Bovine lungworms (Dictyocaulus viviparus) are nematodes which cause a respiratory disease known as verminous bronchitis or pneumonia. In this paper, we describe 20 outbreaks of bovine dictyocaulosis recorded between 2000 and 2023 in Central Argentina. Outbreaks occurred more frequently during the autumn-winter season (from April to August) and affected cattle under 1 year old in beef production systems.
View Article and Find Full Text PDFJ Clin Med
March 2020
Pathology Department, Faculty of Medicine, University of Valencia, 46010 Valencia, Spain.
Background: Due to the lack of a gold standard diagnostic test, reference centres with experienced personnel and costly procedures are needed for primary ciliary dyskinesia (PCD) diagnostics. Diagnostic flowcharts always start with clinical symptoms. Therefore, the aim of this work is to define differential clinical criteria so that only patients clinically compatible with PCD are referred to reference centres.
View Article and Find Full Text PDFBr J Anaesth
February 2019
Nuffield Division of Anaesthetics, University of Oxford, Oxford, UK; Centre for Human and Applied Physiological Sciences, King's College, London, UK; Department of Biomechanics, University of Nebraska Omaha, Omaha, NE, USA. Electronic address:
Background: Tidal recruitment/derecruitment (R/D) of collapsed regions in lung injury has been presumed to cause respiratory oscillations in the partial pressure of arterial oxygen (PaO). These phenomena have not yet been studied simultaneously. We examined the relationship between R/D and PaO oscillations by contemporaneous measurement of lung-density changes and PaO.
View Article and Find Full Text PDFAnn Transl Med
October 2018
Department of Anesthesia, Critical Care and Pain Medicine, Beth Israel Deaconess Medical Center and Harvard Medical School, Boston, MA, USA.
Ventilator management of patients with acute respiratory distress syndrome (ARDS) has been characterized by implementation of basic physiology principles by minimizing harmful distending pressures and preventing lung derecruitment. Such strategies have led to significant improvements in outcomes. Positive end expiratory pressure (PEEP) is an important part of a lung protective strategy but there is no standardized method to set PEEP level.
View Article and Find Full Text PDFSci Rep
September 2017
Nuffield Division of Anaesthetics, University of Oxford, Oxford, United Kingdom.
Arterial oxygen partial pressure can increase during inspiration and decrease during expiration in the presence of a variable shunt fraction, such as with cyclical atelectasis, but it is generally presumed to remain constant within a respiratory cycle in the healthy lung. We measured arterial oxygen partial pressure continuously with a fast intra-vascular sensor in the carotid artery of anaesthetized, mechanically ventilated pigs, without lung injury. Here we demonstrate that arterial oxygen partial pressure shows respiratory oscillations in the uninjured pig lung, in the absence of cyclical atelectasis (as determined with dynamic computed tomography), with oscillation amplitudes that exceeded 50 mmHg, depending on the conditions of mechanical ventilation.
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