Technology and Health Care - Volume 16, issue 5

Authors: Fette, A.

Article Type: Research Article

Abstract: Neck trauma in childhood resulting in trachea rupture lesions is an extremely rare but always life-threatening injury. Even if initial clinical signs are minimal, significant airway compromise always has to be considered. Mechanisms of accident and etiologies regarding especially the true impact forces of the trauma are various making standardized emergency management and health care difficult. Two opposite and exceptional case reports are presented and discussed in front of an extended literature overview.

Keywords: Trachea lesion, trauma impact, emergency management, children

DOI: 10.3233/THC-2008-16501

Citation: Technology and Health Care, vol. 16, no. 5, pp. 319-329, 2008

Authors: Souza, Catiuscia S. | Júnior, Jayme A. Mesquita | Melo, Pedro L.

Article Type: Research Article

Abstract: Physiological studies of swallowing and the diagnosis and treatment of dysphagia are crucially dependent of detailed information of respiratory and feeding events. However, this information has been obtained by indirect and/or expensive methods, as well as by methods demanding exposure to radiation. In this context, the purpose of this study was twofold: (1) describe a new low-cost system for the analysis of the respiratory events during swallowing using the Forced Oscillation Technique and (2) evaluate the performance of this device in the description of physiological events during water swallowing. The device consists of a personal computer adapted to measurement modules …able to characterize the soft palate movement, the elevation of the larynx, the duration of deglutition apnoea, and the direction of airflow at the end of the swallow apnoea. These parameters were studied in eight healthy subjects under conditions of saliva swallowing and three doses of water (5,10 and 20 mL). The system allowed a real time description of the respiratory and feeding events, which were in close agreement with physiological principles. Mean results showed an increase of the apnoea time that was not statistically significant. In contrast, a highly significant increase of respiratory impedance during swallowing was observed (p < 0.0001). The described instrument does not use radiation. It shows itself particularly well suited for studies of deglutition physiology, including mechanisms involved in airway protection during swallowing. It can also be potentially useful contributing to easy clinical bedside evaluations and biofeedback procedures for the rehabilitation of paediatric and elderly patients. Show more

Keywords: Medical instrumentation, respiration, forced oscillations, swallowing apnoea, deglutition, dysphagia

DOI: 10.3233/THC-2008-16502

Citation: Technology and Health Care, vol. 16, no. 5, pp. 331-341, 2008

Authors: Karmonik, Christof | Bismuth, Jean X. | Davies, Mark G. | Lumsden, Alan B.

Article Type: Research Article

Abstract: Objective: To demonstrate the potential role of computational fluid dynamics (CFD) in therapeutic decision making for treatment of vascular pathologies of the human aorta. Methods: CFD simulations with patient specific geometries and patient-specific inflow boundary conditions obtained with magnetic resonance imaging were performed in three cases: 1) mobile thrombus in the aortic arch in a patient with ischemic stroke 2) acute type II B aortic dissection 3) abdominal aortic aneurysm repaired with an endoluminal graft. Blood flow pathlines, wall shear stresses (WSS), dynamic pressures, blood velocities and flow particle resident times were calculated. Results: …Aortic thrombus was indicated as possible source of emboli by flowlines and elevated WSS (8% higher than average WSS at aortic wall) in case 1. This was not identified on conventional imaging. In case 2, the false lumen of the dissection showed elevated pressures and high blood velocities at systole but low pressures and stagnant flow at other times (blood velocity < 0.02 m/s and WSS < 0.1 Pa). Flow disturbances at the reentrance zone of blood from the false lumen were recognized. For case 3, elevated WSS at the landing zone of the endoluminal graft and at the right iliac section together with disturbed flow patterns and increased flow particle resident times were noted. Focal stenoses coincided with the flow disturbances. Measured velocity patterns were qualitatively in agreement with velocity patterns calculated with CFD. Conclusion: CFD simulations provide additional information of the hemodynamics in the diseased human aorta and may have potential in aiding the therapeutic decision making process. Show more

Keywords: Computational fluid dynamics, human aorta, patient specific, type B II aortic dissection, endoluminal graft

DOI: 10.3233/THC-2008-16503

Citation: Technology and Health Care, vol. 16, no. 5, pp. 343-354, 2008

Authors: Evrensel, Cahit A. | Khan, Raquib U. | Krumpe, Peter E.

Article Type: Research Article

Abstract: Basic interaction mechanism between the air flow and viscoelastic mucus layer lining a rigid tube is computationally studied. Linear wave instability theory is applied to the coupled air-mucus system to explore the stability of the interface. Primary velocity profile is taken to be the mean profile of turbulent flow and turbulent fluctuations are neglected. The model predicts that the instability initiates in the form of slow propagating waves on the mucus surface. Onset flow speed at which these waves initiate is very sensitive to mucus viscosity to elasticity ratio at lower range and it approaches to an asymptotic value for …higher values. The results indicate that while the wave length increases, wave speed decreases with increasing mucus viscosity to elasticity ratio. Model also predicts that the waves initiate at lower flow velocities for the turbulent case compared to the published laminar case. Turbulent onset flow speed is only 34% Flow is considered to be turbulent during forced expiration and coughing in central and upper airways. Model predicts that this flow behavior tends to favor wave initiation at lower flow rates and may facilitate cough clearance. Show more

DOI: 10.3233/THC-2008-16504

Citation: Technology and Health Care, vol. 16, no. 5, pp. 355-366, 2008

Authors: Yang, Mingjing | Zhang, Hui | Zheng, Huiru | Wang, Haiying | Lin, Qiang

Article Type: Research Article

Abstract: Dynamic electrocardiogram (ECG) plays an important role in the analysis of heart movement and cardio-diseases. In an attempt to obtain a better understanding of the mechanisms of patterns and differences found in dynamic ECGs, techniques based on different theories such as chaos and fractal theory have been used to extract nonlinear information encoding in dynamics ECG signals. In this paper, we propose an information theory approach to supporting the analysis of dynamic ECG recorded during different time of a day. Mutual information of R-R intervals extracted from four subject groups were calculated and analysed. Results indicate that heart movement is …similar to chaotic movement in many ways. Moreover, the mutual information of R-R intervals exhibits different patterns over different periods of a day and different subject groups, suggesting that it would be a useful tool to support classification analysis of heart movement and cardio related diseases. Show more

Keywords: Dynamic electrocardiogram, mutual information, chaos, coronary artery disease, diabetes

DOI: 10.3233/THC-2008-16505

Citation: Technology and Health Care, vol. 16, no. 5, pp. 367-375, 2008

Authors: Niederer, Peter

Article Type: Editorial

DOI: 10.3233/THC-2008-16506

Citation: Technology and Health Care, vol. 16, no. 5, pp. 379-379, 2008

Authors: McCullagh, P.J. | Zheng, H. | Black, N.D. | Davies, R. | Mawson, S. | McGlade, K.

Article Type: Research Article

DOI: 10.3233/THC-2008-16507

Citation: Technology and Health Care, vol. 16, no. 5, pp. 381-397, 2008

Article Type: Announcement

DOI: 10.3233/THC-2008-16508

Citation: Technology and Health Care, vol. 16, no. 5, pp. 399-399, 2008