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https://www.readbyqxmd.com/read/28918335/modern-diagnosis-of-chronic-thromboembolic-pulmonary-hypertension
#1
Aileen Kharat, Anne-Lise Hachulla, Stéphane Noble, Frédéric Lador
Chronic thromboembolic pulmonary hypertension (CTEPH) should be suspected in patients presenting persistent dyspnea three months after a pulmonary embolism or in patients presenting with acute pulmonary embolism and suggestive images on the CT-scan. For these patients, a specific diagnostic work-up should be performed. First step consists of the ventilation/perfusion (V/Q) scan which is a good screening test due to its high sensitivity and high negative predictive value. Pulmonary angiography remains the gold standard approach for the confirmation of the diagnosis and pre-surgical evaluation of CTEPH...
September 9, 2017: Thrombosis Research
https://www.readbyqxmd.com/read/28910340/successful-1-1-proportion-ventilation-with-a-unique-device-for-independent-lung-ventilation-using-a-double-lumen-tube-without-complications-in-the-supine-and-lateral-decubitus-positions-a-pilot-study
#2
Michał Kowalczyk, Sławomir Sawulski, Wojciech Dąbrowski, Luiza Grzycka-Kowalczyk, Edyta Kotlińska-Hasiec, Agnieszka Wrońska-Sewruk, Artur Florek, Rafał Rutyna
INTRODUCTION: Adequate blood oxygenation and ventilation/perfusion matching should be main goal of anaesthetic and intensive care management. At present, one of the methods of improving gas exchange restricted by ventilation/perfusion mismatching is independent ventilation with two ventilators. Recently, however, a unique device has been developed, enabling ventilation of independent lungs in 1:1, 2:1, 3:1, and 5:1 proportions. The main goal of the study was to evaluate the device's utility, precision and impact on pulmonary mechanics...
2017: PloS One
https://www.readbyqxmd.com/read/28877099/risk-of-pulmonary-embolism-in-patients-with-isolated-great-saphenous-vein-thrombus
#3
Akshya Gupta, Vijay Pandya, Timothy Baran, Vikram S Dogra
Risks associated with isolated great saphenous vein (GSV) thrombosis remain controversial. The purpose of this study is to identify the risk of pulmonary embolism (PE) in patients with isolated GSV thrombosis, particularly those with thrombus within 3 cm of the sapheno-femoral junction. A retrospective chart review of color flow Doppler lower extremity venous ultrasound examinations from an academic hospital from 2011 to 2016 was conducted. Seventy-eight patients were identified as having acute thrombus in their GSV and were then further stratified based on the presence or absence of concomitant deep venous thrombosis (DVT)...
September 4, 2017: Ultrasound Quarterly
https://www.readbyqxmd.com/read/28871590/pulmonary-hypertension-in-diffuse-parenchymal-lung-diseases-is-there-any-benefit-of-pah-specific-therapy
#4
Monika Szturmowicz, Aneta Kacprzak, Jan Kuś
Pulmonary hypertension (PH) is diagnosed in 40-50% of the patients with end-stage diffuse parenchymal lung diseases (DPLD), and it is associated with significant worsening of life expectancy. Latest ERS/ESC guidelines recommend best available treatment of DPLD, and long-term oxygen therapy in the patients with PaO2 less than 60 mm Hg. Pulmonary arterial hypertension (PAH)-targeted drugs are not recommended in PH-DPLD patients, due to the risk of increasing the ventilation-perfusion mismatch, and consequently worsening of hypoxaemia...
2017: Advances in Respiratory Medicine
https://www.readbyqxmd.com/read/28869670/pulmonary-embolism-in-pregnant-patients-assessing-organ-dose-to-pregnant-phantom-and-its-fetus-during-lung-imaging
#5
Laleh Rafat Motavalli, Elie Hoseinian Azghadi, Hashem Miri Hakimabad, Parisa Akhlaghi
PURPOSE: To provide updated radiation dose from diagnostic exams performed for pregnant patients suspected of pulmonary embolism (PE) using the recently developed BREP phantoms of pregnant woman and the fetus. Also to challenge the validity of current recommendations suggest that ventilation/perfusion (V/Q) single photon emission computed tomography (SPECT) vs. computed tomography pulmonary angiography (CTPA) should be considered for diagnosis of PE in radiosensitive groups such as pregnant women...
September 4, 2017: Medical Physics
https://www.readbyqxmd.com/read/28860164/the-endothelium-in-hypoxic-pulmonary-vasoconstriction
#6
Benjamin Grimmer, Wolfgang Michael Kuebler
Hypoxic pulmonary vasoconstriction (HPV) in combination with hypercapnic pulmonary vasoconstriction redistributes pulmonary blood flow from poorly aerated to better ventilated lung regions by an active process of local vasoconstriction. Impairment of HPV results in ventilation-perfusion mismatch and is commonly associated with various lung diseases including pneumonia, sepsis, or cystic fibrosis. Although several regulatory pathways have been identified, considerable knowledge gaps persist, and a unifying concept of the signaling pathways that underlie HPV and their impairment in lung diseases has not yet emerged...
August 31, 2017: Journal of Applied Physiology
https://www.readbyqxmd.com/read/28857808/effect-of-bronchoconstriction-induced-ventilation-perfusion-mismatch-on-uptake-and-elimination-of-isoflurane-and-desflurane
#7
Moritz Kretzschmar, Alf Kozian, James E Baumgardner, Joao Batista Borges, Göran Hedenstierna, Anders Larsson, Thomas Hachenberg, Thomas Schilling
BACKGROUND: Increasing numbers of patients with obstructive lung diseases need anesthesia for surgery. These conditions are associated with pulmonary ventilation/perfusion (VA/Q) mismatch affecting kinetics of volatile anesthetics. Pure shunt might delay uptake of less soluble anesthetic agents but other forms of VA/Q scatter have not yet been examined. Volatile anesthetics with higher blood solubility would be less affected by VA/Q mismatch. We therefore compared uptake and elimination of higher soluble isoflurane and less soluble desflurane in a piglet model...
August 30, 2017: Anesthesiology
https://www.readbyqxmd.com/read/28832374/chronic-thromboembolic-pulmonary-hypertension-epidemiology-diagnosis-and-management
#8
Srikanth Yandrapalli, Sohaib Tariq, Jessica Kumar, Wilbert S Aronow, Ramin Malekan, William H Frishman, Gregg M Lanier
Chronic thromboembolic pulmonary hypertension (CTEPH), classified as WHO group 4 pulmonary hypertension (PH), is an interesting and rare pulmonary vascular disorder secondary to mechanical obstruction of the pulmonary vasculature from thromboembolism resulting in PH. The pathophysiology is complex, beginning with mechanical obstruction of the pulmonary arteries, which eventually leads to arteriopathic changes and vascular remodeling in the non-occluded arteries and in the distal segments of the occluded arteries mediated by thrombus non-resolution, abnormal angiogenesis, endothelial dysfunction, and various local growth factors...
August 18, 2017: Cardiology in Review
https://www.readbyqxmd.com/read/28825949/false-positive-ventilation-perfusion-studies-due-to-nonembolic-pulmonary-artery-compromise
#9
Jonathan Alis, Miriam Hulkower, Anna Shmukler, Kwang J Chun, Leonard M Freeman
Ventilation/perfusion (V/Q) scans are highly sensitive in detecting clinically significant pulmonary embolisms; however, V/Q mismatches are not specific to pulmonary embolism alone, and other etiologies can cause false-positive results. We present 3 cases where the pulmonary vasculature was compromised, from either intraluminal narrowing or external compression, with resultant mismatches. This raises the importance of interpreting V/Q scan results in conjunction with a thorough medical/surgical history and careful analysis of the chest radiograph...
August 19, 2017: Clinical Nuclear Medicine
https://www.readbyqxmd.com/read/28821335/symptoms-are-more-useful-than-echocardiography-in-patient-selection-for%C3%A2-pulmonary-endarterectomy
#10
Laura Donahoe, Rachel Vanderlaan, John Thenganatt, Karen McRae, Anastasia Bykova, Jakov Moric, John Granton, Marc de Perrot
BACKGROUND: Chronic thromboembolic pulmonary hypertension (CTEPH) is still largely underdiagnosed in the general population. Although transthoracic echocardiogram (TTE) is recommended to screen for CTEPH, it may not detect patients with chronic thromboembolic disease (CTED) and mild or exercise-induced pulmonary hypertension (PH) who could also benefit from pulmonary endarterectomy (PEA). METHODS: All patients referred to our CTEPH program with persistent mismatched perfusion defects on ventilation-perfusion (VQ) scan between January 2005 and June 2015 were divided into three groups according to TTE and right heart catheterization (RHC) as follows: (1) typical CTEPH group (PH on RHC and TTE), (2) TTE-negative (neg) CTEPH group (PH on RHC, but not TTE), or (3) CTED group (no PH on RHC and TTE)...
August 16, 2017: Annals of Thoracic Surgery
https://www.readbyqxmd.com/read/28818484/the-physiology-of-submaximal-exercise-the-steady-state-concept
#11
REVIEW
Guido Ferretti, Nazzareno Fagoni, Anna Taboni, Paolo Bruseghini, Giovanni Vinetti
The steady state concept implies that the oxygen flow is invariant and equal at each level along the respiratory system. The same is the case with the carbon dioxide flow. This condition has several physiological consequences, which are analysed. First, we briefly discuss the mechanical efficiency of exercise and the energy cost of human locomotion, as well as the roles played by aerodynamic work and frictional work. Then we analyse the equations describing the oxygen flow in lungs and in blood, the effects of ventilation and of the ventilation - perfusion inequality, and the interaction between diffusion and perfusion in the lungs...
August 15, 2017: Respiratory Physiology & Neurobiology
https://www.readbyqxmd.com/read/28816631/platypnea-orthodeoxia-syndrome-an-unusual-presentation-of-a-complex-disease
#12
Tess Van Meerhaeghe, Steven Droogmans, Shane Hanon, Jeroen Sonck
BACKGROUND: Platypnea-orthodeoxia syndrome (POS) is an uncommon disorder characterized by dyspnea (=platypnea) and desaturation (=orthodeoxia) in upright position and improvement of symptoms and blood oxygenation in supine position. Clinical presentation is heterogeneous and often confuses the clinician. OBJECTIVES: The present case report illustrates a complicated presentation of the underlying syndrome. METHODS: Description of a POS case in a 73-year-old female with thorough workup and tailored treatment...
August 17, 2017: Acta Clinica Belgica
https://www.readbyqxmd.com/read/28814848/pathophysiological-mechanism-of-long-term-noninvasive-ventilation-in-stable-hypercapnic-patients-with-copd-using-functional-respiratory-imaging
#13
Bita Hajian, Jan De Backer, Claire Sneyers, Francisca Ferreira, Katherine C Barboza, Glenn Leemans, Wim Vos, Wilfried De Backer
INTRODUCTION: Patients with severe COPD often develop chronic hypercapnic respiratory failure. Their prognosis worsens and they are more likely to develop exacerbations. This has major influence on the health-related quality of life. Currently, there is no information about the success of long-term noninvasive ventilation (NIV) among patients who receive NIV in acute settings. Also, little is known about the pathophysiological mechanism of NIV. METHODS: Ten Global Initiative for Obstructive Lung Disease stage III and IV COPD patients with respiratory failure who were hospitalized following acute exacerbation were treated with NIV using a Synchrony BiPAP device for 6 months...
2017: International Journal of Chronic Obstructive Pulmonary Disease
https://www.readbyqxmd.com/read/28808575/reduced-ventilation-perfusion-v-q-mismatch-following-endobronchial-valve-insertion-demonstrated-by-gallium-68-v-q-photon-emission-tomography-computed-tomography
#14
Paul Leong, Pierre-Yves Le Roux, Jason Callahan, Shankar Siva, Michael S Hofman, Daniel P Steinfort
Endobronchial valves (EBVs) are increasingly deployed in the management of severe emphysema. Initial studies focussed on volume reduction as the mechanism, with subsequent improvement in forced expiratory volume in 1 s (FEV1). More recent studies have emphasized importance of perfusion on predicting outcomes, though findings have been inconsistent. Gallium-68 ventilation-perfusion (V/Q) photon emission tomography (PET)/computed tomography (CT) is a novel imaging modality with advantages in spatial resolution, quantitation, and speed over conventional V/Q scintigraphy...
September 2017: Respirology Case Reports
https://www.readbyqxmd.com/read/28766495/pulmonary-embolism-with-endovascular-thrombolysis-for-thrombosed-hemodialysis-arteriovenous-access%C3%A2
#15
Yogeshwar Singh Rajaram, Thong Le, Maree Ross-Smith, Andrew Owen, Jason Chuen, Peter F Mount
AIMS: Acute thrombosis of hemodialysis (HD) arteriovenous access is an urgent problem for HD patients and is commonly managed by endovascular thrombolysis. Pulmonary embolism (PE) is a recognized complication of HD access thrombosis and thrombolysis but the risk and outcomes are unclear. This study aims to determine the incidence, predictors, and outcomes of PE after endovascular thrombolysis of HD arteriovenous access in patients presenting with acute thrombosis. MATERIALS AND METHODS: A single-center retrospective study was performed for all adult chronic kidney disease patients undergoing arteriovenous access thrombolysis between January 1, 2012, and December 31, 2014...
September 2017: Clinical Nephrology
https://www.readbyqxmd.com/read/28729471/hypoxic-vascular-response-and-ventilation-perfusion-matching-in-end-stage-copd-may-depend-on-p22phox
#16
Chandran Nagaraj, Christoph Tabeling, Bence M Nagy, Pritesh P Jain, Leigh M Marsh, Rita Papp, Michael Pienn, Martin Witzenrath, Bahil Ghanim, Walter Klepetko, E Kenneth Weir, Stefan Heschl, Grazyna Kwapiszewska, Andrea Olschewski, Horst Olschewski
Chronic obstructive pulmonary disease (COPD) is a heterogeneous disease in which the amount of emphysema and airway disease may be very different between individuals, even in end-stage disease. Emphysema formation may be linked to the involvement of the small pulmonary vessels. The NAPDH oxidase (Nox) family is emerging as a key disease-related factor in vascular diseases, but currently its role in hypoxia-induced pulmonary remodelling in COPD remains unclear.Here we investigate the role of p22phox, a regulatory subunit of Nox, in COPD lungs, hypoxic pulmonary vasoconstriction (HPV), hypoxia-induced pulmonary vascular remodelling and pulmonary hypertension...
July 2017: European Respiratory Journal: Official Journal of the European Society for Clinical Respiratory Physiology
https://www.readbyqxmd.com/read/28721321/correlation-of-ventilation-perfusion-v-q-scan-results-as-compared-with-clinical-probability-of-pulmonary-embolism-in-african-american-population
#17
Fasil Tiruneh, Ahmad Awan, Nicole Hunt, Nahom Tegegn, Daniel Larbi
Introduction Current guidelines suggest the use of the more specific Wells' score could safely reduce the number of unnecessary scans. There is a lack of research to support whether these guidelines apply to the African American population. This study aims to evaluate the correlation of clinical pretest probability of pulmonary embolism (PE) with ventilation-perfusion (V/Q) scan results in a predominantly African American population and to test whether current guidelines based on studies conducted in other populations hold true in this group...
June 14, 2017: Curēus
https://www.readbyqxmd.com/read/28706106/detailed-assessment-of-benefits-and-risks-of-retrievable-inferior-vena-cava-filters-on-patients-with-complicated-injuries-the-da-vinci-multicentre-randomised-controlled-trial-study-protocol
#18
Kwok M Ho, Sudhakar Rao, Stephen Honeybul, Rene Zellweger, Bradley Wibrow, Jeffrey Lipman, Anthony Holley, Alan Kop, Elizabeth Geelhoed, Tomas Corcoran
INTRODUCTION: Retrievable inferior vena cava (IVC) filters have been increasingly used in patients with major trauma who have contraindications to anticoagulant prophylaxis as a primary prophylactic measure against venous thromboembolism (VTE). The benefits, risks and cost-effectiveness of such strategy are uncertain. METHODS AND ANALYSIS: Patients with major trauma, defined by an estimated Injury Severity Score >15, who have contraindications to anticoagulant VTE prophylaxis within 72 hours of hospitalisation to the study centre will be eligible for this randomised multicentre controlled trial...
July 12, 2017: BMJ Open
https://www.readbyqxmd.com/read/28676304/imaging-trends-in-acute-venous-thromboembolic-disease-2000-to-2015
#19
Isaac Wang, Matthew S Davenport, Ella A Kazerooni
PURPOSE: To measure diffusion of new knowledge and correlate imaging utilization for suspected acute venous thromboembolism (VTE) with d-dimer utilization, landmark publications, and institutional guidelines. MATERIALS: Between 2000 and 2015, the number of CT pulmonary angiograms (CTPAs), CTPA combined with indirect CT venography (CTV), ventilation-perfusion (VQ) scans, and lower extremity venous Doppler ultrasound (US) examinations were obtained for inpatients and emergency department (ED) patients and correlated with d-dimer utilization, landmark publications regarding radiation and VTE imaging, and an institutional inpatient best-practice alert requiring VTE prophylaxis assessment (2008)...
July 1, 2017: Journal of the American College of Radiology: JACR
https://www.readbyqxmd.com/read/28673474/new-developments-and-future-challenges-of-nuclear-medicine-and-molecular-imaging-for-pulmonary-embolism
#20
Pierre-Yves Le Roux, Philippe Robin, Pierre-Yves Salaun
Although widely validated, current tests for pulmonary embolism (PE) diagnosis, i.e. computed tomography pulmonary angiography (CTPA) and V/Q planar scintigraphy, have some limitations. Drawbacks of CTPA include the radiation dose, some contra indications and a rising concern about a possible overdiagnosis/overtreatment of PE. On the other hand, V/Q planar scintigraphy has a high rate of non-diagnostic tests responsible for complex diagnostic algorithms. Since the PIOPED study, imaging equipment and radiopharmaceuticals have greatly evolved allowing the introduction of techniques that improve imaging of lung ventilation and perfusion...
June 27, 2017: Thrombosis Research
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