0000000000292711
AUTHOR
Marc Bodenstein
A comparison of micropore membrane inlet mass spectrometry–derived pulmonary shunt measurement with riley shunt in a porcine model
The multiple inert gas elimination technique was developed to measure shunt and the ratio of alveolar ventilation to simultaneous alveolar capillary blood flow in any part of the lung (V(A)'/Q') distributions. Micropore membrane inlet mass spectrometry (MMIMS), instead of gas chromatography, has been introduced for inert gas measurement and shunt determination in a rabbit lung model. However, agreement with a frequently used and accepted method for quantifying deficits in arterial oxygenation has not been established. We compared MMIMS-derived shunt (M-S) as a fraction of total cardiac output (CO) with Riley shunt (R-S) derived from the R-S formula in a porcine lung injury model.To allow a …
Pathogenic lipid‐binding antiphospholipid antibodies are associated with severity of COVID‐19
Abstract Background Coronavirus disease 19 (COVID‐19)–associated coagulopathy is a hallmark of disease severity and poor prognosis. The key manifestations of this prothrombotic syndrome—microvascular thrombosis, stroke, and venous and pulmonary clots—are also observed in severe and catastrophic antiphospholipid syndrome. Antiphospholipid antibodies (aPL) are detectable in COVID‐19 patients, but their association with the clinical course of COVID‐19 remains unproven. Objectives To analyze the presence and relevance of lipid‐binding aPL in hospitalized COVID‐19 patients. Methods Two cohorts of 53 and 121 patients from a single center hospitalized for PCR‐proven severe acute respiratory syndro…
Assessment of regional ventilation distribution: comparison of vibration response imaging (VRI) with electrical impedance tomography (EIT)
BACKGROUND: Vibration response imaging (VRI) is a bedside technology to monitor ventilation by detecting lung sound vibrations. It is currently unknown whether VRI is able to accurately monitor the local distribution of ventilation within the lungs. We therefore compared VRI to electrical impedance tomography (EIT), an established technique used for the assessment of regional ventilation. METHODOLOGY/PRINCIPAL FINDINGS: Simultaneous EIT and VRI measurements were performed in the healthy and injured lungs (ALI; induced by saline lavage) at different PEEP levels (0, 5, 10, 15 mbar) in nine piglets. Vibration energy amplitude (VEA) by VRI, and amplitudes of relative impedance changes (rel.ΔZ) …
Principles of electrical impedance tomography and its clinical application
This review outlines the basic principle, in addition to validated and upcoming clinical use of electrical impedance tomography (EIT). EIT generates functional tomograms of the thorax for detection of changes in regional lung aeration. These images allow an intraindividual comparison of changes in regional lung function. Specifically, EIT aims to optimize ventilation therapy in patients with acute lung failure.PubMed: National Library of Medicine and the National Institutes of Health.Studies with the key words "electrical impedance tomography" since 1983.Qualitative and quantitative results of the studies.We summarize basic principles of the technique and subsequent analyzing methods, and g…
Impact of Model Shape Mismatch on Reconstruction Quality in Electrical Impedance Tomography
Electrical impedance tomography (EIT) is a low-cost, noninvasive and radiation free medical imaging modality for monitoring ventilation distribution in the lung. Although such information could be invaluable in preventing ventilator-induced lung injury in mechanically ventilated patients, clinical application of EIT is hindered by difficulties in interpreting the resulting images. One source of this difficulty is the frequent use of simple shapes which do not correspond to the anatomy to reconstruct EIT images. The mismatch between the true body shape and the one used for reconstruction is known to introduce errors, which to date have not been properly characterized. In the present study we…
Evidence for the utility of cfDNA plasma concentrations to predict disease severity in COVID-19
AbstractCOVID-19 is a pandemic caused by the highly infective SARS-CoV-2. There is a need for biomarkers not only for overall prognosis but also for predicting the response to treatments and thus for improvements in the clinical management of patients with COVID-19. Circulating cell-free DNA (cfDNA) has emerged as a promising biomarker in the assessment of various disease conditions. The aim of this retrospective and observational pilot study was to examine the potential value of cfDNA plasma concentrations as a correlative biomarker in hospitalized COVID-19 patients. Lithium-Heparin plasma samples were obtained from twenty-one COVID-19 patients during hospitalization in the University Medi…
Chest electrical impedance tomography examination, data analysis, terminology, clinical use and recommendations: consensus statement of the translational eit development study group
Electrical impedance tomography (EIT) has undergone 30 years of development. Functional chest examinations with this technology are considered clinically relevant, especially for monitoring regional lung ventilation in mechanically ventilated patients and for regional pulmonary function testing in patients with chronic lung diseases. As EIT becomes an established medical technology, it requires consensus examination, nomenclature, data analysis and interpretation schemes. Such consensus is needed to compare, understand and reproduce study findings from and among different research groups, to enable large clinical trials and, ultimately, routine clinical use. Recommendations of how EIT findi…
Toward morphological thoracic EIT: major signal sources correspond to respective organ locations in CT.
Lung and cardiovascular monitoring applications of electrical impedance tomography (EIT) require localization of relevant functional structures or organs of interest within the reconstructed images. We describe an algorithm for automatic detection of heart and lung regions in a time series of EIT images. Using EIT reconstruction based on anatomical models, candidate regions are identified in the frequency domain and image-based classification techniques applied. The algorithm was validated on a set of simultaneously recorded EIT and CT data in pigs. In all cases, identified regions in EIT images corresponded to those manually segmented in the matched CT image. Results demonstrate the abilit…
Observation of ventilation-induced Spo(2) oscillations in pigs: first step to noninvasive detection of cyclic recruitment of atelectasis?
High arterial partial oxygen pressure (Pao(2)) oscillations within the respiratory cycle were described recently in experimental acute lung injury. This phenomenon has been related to cyclic recruitment of atelectasis and varying pulmonary shunt fractions. Noninvasive detection of Spo(2) (oxygen saturation measured by pulse oximetry) as an indicator of cyclic collapse of atelectasis, instead of recording Pao(2) oscillations, could be of clinical interest in critical care. Spo(2) oscillations were recorded continuously in three different cases of lung damage to demonstrate the technical feasibility of this approach. To deduce Pao(2) from Spo(2), a mathematical model of the hemoglobin dissoci…
Elektrolyt- und Säure-Basen-Haushalt
Das Gesamtkorpernatrium eines 70 kg schweren Menschen liegt bei 4200 mmol. Davon befi nden sich 40 % im Knochen, 10 % intra- und transzellular und 50 % im Extrazellularraum. Die intrazellulare Natriumkonzentration wird mit 5−20 mmol/l je nach Gewebe und Nachweismethode angegeben. Die Natriumkonzentration im Extrazellularraum liegt bei rund 145 mmol/l und wird durch osmotische Mechanismen relativ eng konstant gehalten. Natrium ist als wichtigstes Kation im extrazellularen Raum zusammen mit den Anionen Chlorid (105 mmol/l) und Bicarbonat (26 mmol/l) fur die Osmolaritat verantwortlich. Der Konzentrationsgradient zwischen intra- und extrazellularem Natrium wird durch das Natrium-Kalium-ATPase-E…