scholarly journals Bayesian inference of multi-sensors impedance cardiography for detection of aortic dissection

Author(s):  
Vahid Badeli ◽  
Sascha Ranftl ◽  
Gian Marco Melito ◽  
Alice Reinbacher-Köstinger ◽  
Wolfgang Von Der Linden ◽  
...  

Purpose This paper aims to introduce a non-invasive and convenient method to detect a life-threatening disease called aortic dissection. A Bayesian inference based on enhanced multi-sensors impedance cardiography (ICG) method has been applied to classify signals from healthy and sick patients. Design/methodology/approach A 3D numerical model consisting of simplified organ geometries is used to simulate the electrical impedance changes in the ICG-relevant domain of the human torso. The Bayesian probability theory is used for detecting an aortic dissection, which provides information about the probabilities for both cases, a dissected and a healthy aorta. Thus, the reliability and the uncertainty of the disease identification are found by this method and may indicate further diagnostic clarification. Findings The Bayesian classification shows that the enhanced multi-sensors ICG is more reliable in detecting aortic dissection than conventional ICG. Bayesian probability theory allows a rigorous quantification of all uncertainties to draw reliable conclusions for the medical treatment of aortic dissection. Originality/value This paper presents a non-invasive and reliable method based on a numerical simulation that could be beneficial for the medical management of aortic dissection patients. With this method, clinicians would be able to monitor the patient’s status and make better decisions in the treatment procedure of each patient.

2020 ◽  
Vol 11 (1) ◽  
pp. 38-48
Author(s):  
V. Badeli ◽  
G. M. Melito ◽  
A. Reinbacher-Köstinger ◽  
O. Bíró ◽  
K. Ellermann

AbstractImpedance cardiography (ICG) is a non-invasive method to evaluate several cardiodynamic parameters by measuring the cardiac-synchronous changes in the dynamic transthoracic electrical impedance. ICG allows us to identify and quantify conductivity changes inside the thorax by measuring the impedance on the thorax during a cardiac cycle. Pathologic changes in the aorta, like aortic dissection, will alter the aortic shape as well as the blood flow and consequently, the impedance cardiogram. This fact distorts the evaluated cardiodynamic parameters, but it could lead to the possibility to identify aortic pathology. A 3D numerical simulation model is used to compute the impedance changes on the thorax surface in case of the type B aortic dissection. A sensitivity analysis is applied using this simulation model to investigate the suitability of different electrode configurations considering several patient-specific cases. Results show that the remarkable pathological changes in the aorta caused by aortic dissection alters the impedance cardiogram significantly.


2021 ◽  
Vol 51 (1) ◽  
pp. 10-15
Author(s):  
Kenneth V Iserson ◽  
Sri Devi Jagjit ◽  
Balram Doodnauth

Acute thoracic aortic dissection is an uncommon, although not rare, life-threatening condition. With protean signs and symptoms that often suggest more common cardiac or pulmonary conditions, it can be difficult to diagnose. Ultrasound has proven useful in making the correct diagnosis. This case demonstrates that training gained using standard ultrasound machines can be easily and successfully adapted to newer handheld ultrasound devices. The examination technique using the handheld device is illustrated with photos and a video.


Measurement ◽  
2021 ◽  
Vol 174 ◽  
pp. 108992
Author(s):  
Adriana Machado Malafaia da Mata ◽  
Bruno Furtado de Moura ◽  
Marcio Ferreira Martins ◽  
Francisco Hernán Sepúlveda Palma ◽  
Rogério Ramos

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mark Campbell ◽  
Roslyn Dakin ◽  
Symon Stowe ◽  
Kira Burton ◽  
Brianna Raven ◽  
...  

AbstractRestraint asphyxia has been proposed as a mechanism for some arrest-related deaths that occur during or shortly after a suspect is taken into custody. Our analysis of the literature found that prone positioning, weight applied to the back, recovery after simulated pursuit, and restraint position have led to restrictive, but non life-threatening respiratory changes when tested in subsets. However, the combined effects of all four parameters have not been tested together in a single study. We hypothesized that a complete protocol with high-sensitivity instrumentation could improve our understanding of breathing physiology during weighted restraint. We designed an electrical impedance tomography (EIT)-based protocol for this purpose and measured the 3D distribution of ventilation within the thorax. Here, we present the results from a study on 17 human subjects that revealed FRC declines during weighted restrained recovery from exercise for subjects in the restraint postures, but not the control posture. These prolonged FRC declines were consistent with abdominal muscle recruitment to assist the inspiratory muscles, suggesting that subjects in restraint postures have increased work of breathing compared to controls. Upon removal of the weighted load, lung reserve volumes gradually increased for the hands-behind-the-head restraint posture but continued to decrease for subjects in the hands-behind-the-back restraint posture. We discuss the possible role this increased work of breathing may play in restraint asphyxia.


mSphere ◽  
2019 ◽  
Vol 4 (5) ◽  
Author(s):  
Suresh Ambati ◽  
Emma C. Ellis ◽  
Jianfeng Lin ◽  
Xiaorong Lin ◽  
Zachary A. Lewis ◽  
...  

ABSTRACT Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus cause life-threatening candidiasis, cryptococcosis, and aspergillosis, resulting in several hundred thousand deaths annually. The patients at the greatest risk of developing these life-threatening invasive fungal infections have weakened immune systems. The vulnerable population is increasing due to rising numbers of immunocompromised individuals as a result of HIV infection or immunosuppressed individuals receiving anticancer therapies and/or stem cell or organ transplants. While patients are treated with antifungals such as amphotericin B, all antifungals have serious limitations due to lack of sufficient fungicidal effect and/or host toxicity. Even with treatment, 1-year survival rates are low. We explored methods of increasing drug effectiveness by designing fungicide-loaded liposomes specifically targeted to fungal cells. Most pathogenic fungi are encased in cell walls and exopolysaccharide matrices rich in mannans. Dectin-2 is a mammalian innate immune membrane receptor that binds as a dimer to mannans and signals fungal infection. We coated amphotericin-loaded liposomes with monomers of Dectin-2’s mannan-binding domain, sDectin-2. sDectin monomers were free to float in the lipid membrane and form dimers that bind mannan substrates. sDectin-2-coated liposomes bound orders of magnitude more efficiently to the extracellular matrices of several developmental stages of C. albicans, C. neoformans, and A. fumigatus than untargeted control liposomes. Dectin-2-coated amphotericin B-loaded liposomes reduced the growth and viability of all three species more than an order of magnitude more efficiently than untargeted control liposomes and dramatically decreased the effective dose. Future efforts focus on examining pan-antifungal targeted liposomal drugs in animal models of fungal diseases. IMPORTANCE Invasive fungal diseases caused by Candida albicans, Cryptococcus neoformans, and Aspergillus fumigatus have mortality rates ranging from 10 to 95%. Individual patient costs may exceed $100,000 in the United States. All antifungals in current use have serious limitations due to host toxicity and/or insufficient fungal cell killing that results in recurrent infections. Few new antifungal drugs have been introduced in the last 2 decades. Hence, there is a critical need for improved antifungal therapeutics. By targeting antifungal-loaded liposomes to α-mannans in the extracellular matrices secreted by these fungi, we dramatically reduced the effective dose of drug. Dectin-2-coated liposomes loaded with amphotericin B bound 50- to 150-fold more strongly to C. albicans, C. neoformans, and A. fumigatus than untargeted liposomes and killed these fungi more than an order of magnitude more efficiently. Targeting drug-loaded liposomes specifically to fungal cells has the potential to greatly enhance the efficacy of most antifungal drugs.


2021 ◽  
Vol 19 ◽  
Author(s):  
Jianing Wu ◽  
Ilgiz Gareev ◽  
Ozal Beylerli ◽  
Albert Mukhamedzyanov ◽  
Valentin Pavlov ◽  
...  

Aim: Intracranial aneurysms (IAs) are characterized by abnormal dilation and thinning of the cerebral vessels wall, leading to rupture and life-threatening aneurysmal subarachnoid hemorrhage (aSAH) condition. This dictates the need to find new biomarkers that predict the presence of IAs and the risk of their rupture. The aim of this study was to measure circulating miR-126 at various time points post-aSAH to identify the timing of peak levels. Methods: Plasma samples from 62 patients with unruptured IAs (UIAs), 80 patients with aSAH at various time points (1, 3, 7, and 14 days post-event), and 47 healthy control were collected and subjected to qRT-PCR analyses for the expression levels of circulating miR-126. ROC curve and AUC were used to evaluate the diagnostic value of circulating miR-126. Results: The expression levels of circulating miR-126 were increased in patients with UIAs than in the healthy control. Furthermore, the expression levels of circulating miR-126 rose substantially from day 1 to day 7, but with a moderate decrease from day 7 to day 14 in plasma of patients with aSAH. The peak was observed on day 7. The AUC for miR-126 was 0.75, 0.75, 0.82, 0.87, and 0.79, respectively, and demonstrated that circulating miR-126 displayed considerable accuracy in discriminating plasma of patients with UIAs and patients after aSAH at various time points from a healthy control. Conclusion: Our results indicated that circulating miR-126 in plasma samples could be served as a potential non-invasive biomarker in IAs detection and prevention IAs with a high risk of rupture.


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