Sökning: "electrical impedance tomography"

Visar resultat 1 - 5 av 8 avhandlingar innehållade orden electrical impedance tomography.

  1. 1. Pulmonary ventilation and perfusion assessed by electrical impedance tomography - Experimental studies in pigs

    Författare :Anneli Fagerberg; Göteborgs universitet; []
    Nyckelord :electrical impedance tomography; V Q matching; pig; endotoxinaemic ALI; ACE inhibitor;

    Sammanfattning : Pulmonary ventilation and perfusion and ventilation/perfusion (V/Q) matching determine gas exchange in every lung unit in the healthy state and in the pathologically altered lung. Mismatch of V and Q lead to hypoxaemia and hypercapnia and monitoring of V/Q relations are thus important in critical illness. LÄS MER

  3. 2. Sensitivity Analysis and Material Parameter Estimation using Electromagnetic Modelling

    Författare :Therese Sjödén; Sven Nordebo; Börje Nilsson; Margaret Cheney; Linnéuniversitetet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sensitivity analysis; material parameter; Fisher information; Cramér-Rao bound; electromagnetic modelling; grain angle; wood; electrical impedance tomography; inverse problems; känslighetsanalys; estimering; materialparameter; Fisher- information; Cramér-Rao-gränsen; elektromagnetisk modellering; fibervinkel; trä; elektrisk impedanstomografi; inversa problem; Waves; Signals and Systems; Vågor; signaler och system;

    Sammanfattning : Estimating parameters is the problem of finding their values from measurements and modelling. Parameters describe properties of a system; material, for instance, are defined by mechanical, electrical, and chemical parameters. Fisher information is an information measure, giving information about how changes in the parameter effect the estimation. LÄS MER

  4. 3. Titrating Open Lung PEEP in Acute Lung Injury : A clinical method based on changes in dynamic compliance

    Författare :Fernando Suarez Sipmann; Göran Hedenstierna; Hans Hedenström; Stefan Lundin; Uppsala universitet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; PEEP; open lung; recruitment; dead space; electrical impedance tomography; ARDS.; Medicine; Medicin;

    Sammanfattning : The recognition that supportive mechanical ventilation can also damage the lung, the so called ventilation induced lung injury (VILI), has revived the more than 40 year long debate on the optimal level of PEEP to be used. It is established that the prevention of VILI improves patient outcome and that PEEP exerts protective effects by preventing unstable diseased alveoli from collapsing. LÄS MER

  5. 4. Transpulmonary pressure during mechanical ventilation

    Författare :Christina Grivans; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Mechanical ventilation; Acute lung injury; Acute respiratory distress syndrome; Lung volume measurements; Electric Impedance diagnostic use; Lung elastance; Transpulmonary pressure; Esophageal pressure;

    Sammanfattning : Background: Mechanical ventilation can aggravate lung injury by repetitive opening and closing of lung units, overdistention and undue pressure on pulmonary structures. Guidelines exist for lung protective ventilation, but individualized ventilator settings, based on partitioning of respiratory mechanics in pulmonary and chest wall complex components, would be beneficial. LÄS MER

  7. 5. Topology Optimization for Wave Propagation Problems

    Författare :Eddie Wadbro; Martin Berggren; Steven J. Cox; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Scientific Computing; Beräkningsvetenskap;

    Sammanfattning : This thesis considers topology optimization methods for wave propagation problems. These methods make no a priori assumptions on topological properties such as the number of bodies involved in the design. The performed studies address problems from two different areas, acoustic wave propagation and microwave tomography. LÄS MER