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https://www.readbyqxmd.com/read/29793015/right-atrial-anomalous-muscle-bundle-presenting-with-acute-superior-vena-cava-syndrome-and-pulmonary-embolism-surgical-management
#1
Jeko M Madjarov, Michael G Katz, Sophia Madjarova, Svetozar Madzharov, Frank R Arko, David W Miller, Francis Robicsek
BACKGROUND: An anomalous muscle bundle crossing the right atrial cavity represents a pathological finding with unproved clinical significance. This congenital anomaly may be difficult to recognize via echocardiography and could be confused with other intra-cavitary lesions. METHODS: We report a case of a 53-year-old female presented to the cardio-vascular service with acute superior vena cava syndrome and sub-massive pulmonary embolism. RESULTS: The patient underwent venography confirming superior vena cava stenosis...
May 21, 2018: Annals of Vascular Surgery
https://www.readbyqxmd.com/read/29790144/-prone-position-and-nursing-care
#2
Shu-Ju Lu, Shiao-Pei Wang
Acute respiratory distress syndrome (ARDS) is a life-threatening disease, as acute inflammation in the lungs typically leads to hypoxia and symptoms of dyspnea. The treatment modalities of ARDS include mechanical ventilation, corticosteroid, extracorporeal membranous oxygenation, inhaled nitrogen oxide, and the prone position. Among these, the prone position is supported by evidence showing significantly reduced mortality in patients that adopt this modality. Lying in the prone position reduces atelectatic lung volumes by recruitment of dependent parts and facilitates normal regulation of alveolar ventilation, giving better-matched ventilation perfusion and, thus, improved oxygenation...
June 2018: Hu Li za Zhi the Journal of Nursing
https://www.readbyqxmd.com/read/29776385/generation-of-ventilation-perfusion-ratio-map-in-surgical-patients-by-dual-energy-ct-after-xenon-inhalation-and-intravenous-contrast-media
#3
Kohei Aoki, Yotaro Izumi, Wataru Watanabe, Yuji Shimizu, Hisato Osada, Norinari Honda, Toshihide Itoh, Mitsuo Nakayama
BACKGROUND: While many studies have evaluated the change in lung volume before and after lung resection and correlated this with pulmonary function test results, there is very little evidence on the changes in ventilation perfusion ratio (V/Q) before versus after lung resection. In the present pilot study, we evaluated if V/Q mapping can be constructed using dual energy CT images. METHODS: Thirty-one lung cancer patients planned for pulmonary resection were included in this study...
May 18, 2018: Journal of Cardiothoracic Surgery
https://www.readbyqxmd.com/read/29761310/characteristics-of-patients-with-a-relatively-greater-minimum-ve-vco-2-against-peak-vo-2-and-impaired-exercise-tolerance
#4
Taisuke Nakade, Hitoshi Adachi, Makoto Murata, Shigeru Oshima
PURPOSE: Cardiopulmonary exercise testing (CPX) is used to evaluate functional capacity and assess prognosis in cardiac patients. Ventilatory efficiency (VE/VCO2 ) reflects ventilation-perfusion mismatch; the minimum VE/VCO2 value (minVE/VCO2 ) is representative of pulmonary arterial blood flow in individuals without pulmonary disease. Usually, minVE/VCO2 has a strong relationship with the peak oxygen uptake (VO2 ), but dissociation can occur. Therefore, we investigated the relationship between minVE/VCO2 and predicted peak VO2 (peak VO2 %) and evaluated the parameters associated with a discrepancy between these two parameters...
May 14, 2018: European Journal of Applied Physiology
https://www.readbyqxmd.com/read/29726838/estimating-regions-of-air-trapping-from-electrical-impedance-tomography-data
#5
Jennifer L Mueller, Peter A Muller, Michelle Mellenthin, Rashmi Murthy, Michael Capps, Melody Alsaker, Robin Deterding, Scott D Sagel, Emily DeBoer
OBJECTIVE: Electrical impedance tomography (EIT) has been shown as a viable non-invasive, bedside imaging modality to monitor lung function.This paper introduces a method for identifying regions of air trapping from EIT data collected during tidal breathing and breath-holding maneuvers. APPROACH: Ventilation-perfusion index maps are computed from dynamic EIT images. These maps are then used to identify regions of air trapping in the area of the lung as regions that are poorly ventilated but well perfused throughout the breathing and cardiac cycles...
May 4, 2018: Physiological Measurement
https://www.readbyqxmd.com/read/29719268/functional-morphometry-for-the-estimation-of-the-alveolar-surface-area-in-prematurely-born-infants
#6
Theodore Dassios, Konstantinos G Dassios, George Dassios
Conventionally, the alveolar surface area (SA ) has been measured by using post-mortem morphometry. Such studies have highlighted that SA in prematurely-born infants is markedly smaller when compared to term-born infants as a result of postnatal impairment or arrest of alveolar development. We herein explore how, non-invasive measurements of the ventilation/perfusion ratio (VA /Q) can be used to estimate SA in prematurely-born surviving, convalescent infants. We also compare SA in prematurely-born infants measured at term-corrected age, to term-born infants using previously published datasets of VA /Q...
April 29, 2018: Respiratory Physiology & Neurobiology
https://www.readbyqxmd.com/read/29695441/pulmonary-ventilation-perfusion-mismatch-a-novel-hypothesis-for-how-diving-vertebrates-may-avoid-the-bends
#7
REVIEW
Daniel Garcia Párraga, Michael Moore, Andreas Fahlman
Hydrostatic lung compression in diving marine mammals, with collapsing alveoli blocking gas exchange at depth, has been the main theoretical basis for limiting N2 uptake and avoiding gas emboli (GE) as they ascend. However, studies of beached and bycaught cetaceans and sea turtles imply that air-breathing marine vertebrates may, under unusual circumstances, develop GE that result in decompression sickness (DCS) symptoms. Theoretical modelling of tissue and blood gas dynamics of breath-hold divers suggests that changes in perfusion and blood flow distribution may also play a significant role...
April 25, 2018: Proceedings. Biological Sciences
https://www.readbyqxmd.com/read/29687908/hepatopulmonary-disorders-gas-exchange-and-vascular-manifestations-in-chronic-liver-disease
#8
Robert Rodríguez-Roisin, Michael J Krowka, Alvar Agustí
This review concentrates on the determinants of gas exchange abnormalities in liver-induced pulmonary vascular disorders, more specifically in the hepatopulmonary syndrome. Increased alveolar-arterial O2 difference, with or without different levels of arterial hypoxemia, and reduced diffusing capacity represent the most characteristic gas exchange disturbances in the absence of cardiac and pulmonary comorbidities. Pulmonary gas exchange abnormalities in the hepatopulmonary syndrome are unique encompassing all three pulmonary factors determining arterial PO2 , that is, ventilation-perfusion imbalance, increased intrapulmonary shunt and oxygen diffusion limitation that, combined, interplay with two relevant nonpulmonary determinants, that is, increased total ventilation and high cardiac output...
March 25, 2018: Comprehensive Physiology
https://www.readbyqxmd.com/read/29680830/pulmonary-perfusion-using-intrabronchial-capnography-in-pulmonary-artery-stenosis
#9
Hiroki Nishine, Hiromi Muraoka, Takeo Inoue, Teruomi Miyazawa, Masamichi Mineshita
Stenting at the flow-limiting segment can improve the ventilation-perfusion ratio in patients with central airway stenosis. However, there is no quantitative examination for assessing the perfusion status during interventional bronchoscopy. Intrabronchial capnography can estimate regional gas exchange by measuring carbon dioxide concentration. We herein report a case of bilateral bronchial stenosis where stenting was able to improve ventilation-perfusion ratio using intrabronchial capnography. A 44-year-old man was admitted to our institution with orthopnea...
April 20, 2018: Respiration; International Review of Thoracic Diseases
https://www.readbyqxmd.com/read/29680814/spect-v-q-for-the-diagnosis-of-pulmonary-embolism-protocol-for-a-systematic-review-and-meta-analysis-of-diagnostic-accuracy-and-clinical-outcome
#10
Pierre-Yves Le Roux, Philippe Robin, Cécile Tromeur, Alexandra Davis, Helia Robert-Ebadi, Marc Carrier, Francis Couturaud, Grégoire Le Gal, Pierre-Yves Salaun
INTRODUCTION: Single photon emission computed tomography ventilation/perfusion (SPECT V/Q) imaging has many proponents within the nuclear medicine community and has already largely replaced planar V/Q scintigraphy in daily practice for the diagnosis of pulmonary embolism (PE). However, the test is still described in clinical guidelines as an experimental test because of insufficient evidence. METHODS AND ANALYSIS: We will conduct a systematic review and a meta-analysis of diagnostic accuracy and management outcome studies involving patients evaluated with V/Q SPECT for suspected acute PE...
April 21, 2018: BMJ Open
https://www.readbyqxmd.com/read/29678310/grossly-abnormal-ventilation-perfusion-spect-study-in-idiopathic-pulmonary-arterial-hypertension-without-thromboembolism
#11
Kenneth Chan, John G Coghlan, Margaret Hall, Jamanda Haddock, Alan Bates, Benjamin E Schreiber
Pulmonary hypertension is a serious condition with multiple underlying aetiologies which require different treatment strategies. We present a case of severe idiopathic pulmonary arterial hypertension in a 20-year-old patient with ongoing breathlessness. She was initially diagnosed with asthma and panic attacks in community care. As the symptoms became progressively worse, she was referred for pulmonary hypertension clinic assessment. Ventilation/perfusion single-photon emission computed tomography (V/Q SPECT) showed grossly abnormal perfusion defects which were mismatched to the ventilation scan, suggestive of chronic thromboembolic disease...
January 31, 2018: Heart, Lung & Circulation
https://www.readbyqxmd.com/read/29659198/in-silico-modeling-of-oxygen-enhanced-mri-of-specific-ventilation
#12
Wendy Kang, Merryn H Tawhai, Alys R Clark, Rui C Sá, Eric T Geier, G Kim Prisk, Kelly S Burrowes
Specific ventilation imaging (SVI) proposes that using oxygen-enhanced 1H MRI to capture signal change as subjects alternatively breathe room air and 100% O2 provides an estimate of specific ventilation distribution in the lung. How well this technique measures SV and the effect of currently adopted approaches of the technique on resulting SV measurement is open for further exploration. We investigated (1) How well does imaging a single sagittal lung slice represent whole lung SV? (2) What is the influence of pulmonary venous blood on the measured MRI signal and resultant SVI measure? and (3) How does inclusion of misaligned images affect SVI measurement? In this study, we utilized two patient-based in silico models of ventilation, perfusion, and gas exchange to address these questions for normal healthy lungs...
April 2018: Physiological Reports
https://www.readbyqxmd.com/read/29599604/review-article-update-on-current-and-emergent-data-on-hepatopulmonary-syndrome
#13
REVIEW
Stergios Soulaidopoulos, Evangelos Cholongitas, George Giannakoulas, Maria Vlachou, Ioannis Goulis
Hepatopulmonary syndrome (HPS) is a frequent pulmonary complication of end-stage liver disease, characterized by impaired arterial oxygenation induced by intrapulmonary vascular dilatation. Its prevalence ranges from 4% to 47% in patients with cirrhosis due to the different diagnostic criteria applied among different studies. Nitric oxide overproduction and angiogenesis seem to be the hallmarks of a complicated pathogenetic mechanism, leading to intrapulmonary shunting and ventilation-perfusion mismatch. A classification of HPS according to the severity of hypoxemia has been suggested...
March 28, 2018: World Journal of Gastroenterology: WJG
https://www.readbyqxmd.com/read/29599070/postoperative-d-dimer-predicts-venous-thromboembolism-in-patients-undergoing-urologic-tumor-surgery
#14
An Shi, Jiwei Huang, Xun Wang, Mingyang Li, Jin Zhang, Yonghui Chen, Yiran Huang
PURPOSE: We examined the incidence of pulmonary thromboembolism (PE) and deep venous thromboembolism (DVT) in patients who underwent urologic tumor surgery. The aim of this study was to investigate the postoperative D-dimer for prediction of venous thromboembolism events (VTE), as well as to identify other risk factors associated with the occurrence of thromboembolisms. PATIENTS AND METHODS: This was a prospective observational cohort study, which included 1,269 patients who underwent major urologic tumor surgery, from August 2015 to February 2017, at our center...
March 26, 2018: Urologic Oncology
https://www.readbyqxmd.com/read/29563783/changes-in-ventilation-perfusion-during-and-after-an-copd-exacerbation-an-assessment-using-fluid-dynamic-modeling
#15
Bita Hajian, Jan De Backer, Wim Vos, Wouter H van Geffen, Paul De Winter, Omar Usmani, Tony Cahn, Huib Am Kerstjens, Massimo Pistolesi, Wilfried De Backer
Introduction: Severe exacerbations associated with chronic obstructive pulmonary disease (COPD) that require hospitalization significantly contribute to morbidity and mortality. Definitions for exacerbations are very broad, and it is unclear whether there is one predominant underlying mechanism that leads to them. Functional respiratory imaging (FRI) with modeling provides detailed information about airway resistance, hyperinflation, and ventilation-perfusion (V/Q) mismatch during and following an acute exacerbation...
2018: International Journal of Chronic Obstructive Pulmonary Disease
https://www.readbyqxmd.com/read/29504087/the-diagnostic-utility-of-d-dimer-and-other-clinical-variables-in-pregnant-and-post-partum-patients-with-suspected-acute-pulmonary-embolism
#16
Hyun Choi, Dinesh Krishnamoorthy
BACKGROUND: Pulmonary embolism (PE) during pregnancy remains one of the leading causes of maternal morbidity and mortality in the developed world. However, there is a paucity of high-quality evidence resulting in a lack of consensus in managing this group of patients. The aims of the study were to address the diagnostic utility of D-dimer for suspected PE in pregnant and post-partum patients and to identify any clinical presentation variables that are predictors of PE in this group of patients...
March 5, 2018: International Journal of Emergency Medicine
https://www.readbyqxmd.com/read/29502865/use-of-the-d-dimer-for-detecting-pulmonary-embolism-in-the-emergency-department
#17
Nancy Glober, Christopher R Tainter, Jesse Brennan, Mark Darocki, Morgan Klingfus, Michelle Choi, Brenna Derksen, Frances Rudolf, Gabriel Wardi, Edward Castillo, Theodore Chan
BACKGROUND: Assessment for pulmonary embolism (PE) in the emergency department (ED) remains complex, involving clinical decision tools, blood tests, and imaging. OBJECTIVE: Our objective was to examine the test characteristics of the high-sensitivity d-dimer for the diagnosis of PE at our institution and evaluate use of the d-dimer and factors associated with a falsely elevated d-dimer. METHODS: We retrospectively collected data on adult patients evaluated with a d-dimer and computed tomography (CT) pulmonary angiogram or ventilation perfusion scan at two EDs between June 4, 2012 and March 30, 2016...
May 2018: Journal of Emergency Medicine
https://www.readbyqxmd.com/read/29493500/-the-choice-of-diagnostic-modality-for-acute-pulmonary-embolism
#18
Jonas Munch Nielsen, Jann Mortensen
The diagnosis of pulmonary embolism (PE) relies on clinical assessment, D-dimer test and diagnostic imaging. Modern CT pulmonary angiography (CTPA), ventilation/perfusion  single-photon emission computed tomography (SPECT) and SPECT/CT are rather equal in terms of sensitivity, specificity and inconclusive results for the diagnosis of PE, outper-forming planar lung scintigraphy. Furthermore, SPECT/CT and CTPA can both provide important information regarding differential diagnoses. Thus, the choice of primary diag-nostic modality relies on local expertise, availability and special circumstances like radiation dose, contraindications and the clinical urgency...
February 19, 2018: Ugeskrift for Laeger
https://www.readbyqxmd.com/read/29481374/can-mathematical-modeling-explain-the-measured-magnitude-of-the-second-gas-effect
#19
Ben Korman, Ranjan K Dash, Philip J Peyton
BACKGROUND: Recent clinical studies suggest that the magnitude of the second gas effect is considerably greater on arterial blood partial pressures of volatile agents than on end-expired partial pressures, and a significant second gas effect on blood partial pressures of oxygen and volatile agents occurs even at relatively low rates of nitrous oxide uptake. We set out to further investigate the mechanism of this phenomenon with the help of mathematical modeling. METHODS: Log-normal distributions of ventilation and blood flow were generated representing the range of ventilation-perfusion scatter seen in patients during general anesthesia...
February 26, 2018: Anesthesiology
https://www.readbyqxmd.com/read/29452100/a-new-noninvasive-method-of-measuring-impaired-pulmonary-gas-exchange-in-lung-disease-an-outpatient-study
#20
John B West, Daniel R Crouch, Janelle M Fine, Dipen Makadia, Daniel L Wang, G Kim Prisk
BACKGROUND: It would be valuable to have a noninvasive method of measuring impaired pulmonary gas exchange in patients with lung disease and thus reduce the need for repeated arterial punctures. This study reports the results of using a new test in a group of outpatients attending a pulmonary clinic. METHODS: Inspired and expired partial pressure of oxygen (PO2 ) and Pco2 are continually measured by small, rapidly responding analyzers. The arterial PO2 is calculated from the oximeter blood oxygen saturation level and the oxygen dissociation curve...
February 13, 2018: Chest
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