Sökning: "ventilation-perfusion ratio"

Visar resultat 1 - 5 av 6 avhandlingar innehållade orden ventilation-perfusion ratio.

  1. 1. The Effect of CO2-Pneumoperitoneum on Ventilation Perfusion Distribution of the Lung

    Författare :Christof Strang; Göran Hedenstierna; Suzanne Odeberg-Wernerman; Uppsala universitet; []
    Nyckelord :lung; atelectasis; computed tomography; multiple inert gas elimination technique; model; pig; Pa–ECO2 ratio; surgery; laparoscopy; lung; blood flow; single photon emission computed tomography; ventilation perfusion distribution; gas exchange; hypoxic pulmonary vasoconstriction; MEDICINE; MEDICIN;

    Sammanfattning : Laparoscopic operations are a common and popular way for abdominal procedures. They are usually performed by insufflation of carbon dioxide (CO2) into the abdominal cavity. However, insufflation of CO2 may interfere with cardiac and circulatory as well as respiratory functions. The CO2-pneumoperitoneum (PP) may cause hypercarbia and acidosis. LÄS MER

  2. 2. Ventilation and Lung Volume During Sleep and in Obstructive Sleep Apnea

    Författare :Jonas Appelberg; Göran Hedenstierna; Christer Janson; Karl Franklin; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Physiology; Sleep; Ventilation; Sleep apnea syndromes; Snoring; Lung volume; Respiration; Computed tomography; Ventilatory response; Ventilation-perfusion; Airway closure; Fysiologi; Physiology; Fysiologi; klinisk fysiologi; Clinical Physiology;

    Sammanfattning : Obstructive sleep apnea (OSA) appears to affect up to 5% of the population. The extent to what pulmonary function awake and during sleep relates to obstructive breathing and hypoxemia during sleep in these patients is unclear. LÄS MER

  3. 3. Attenuation correction in pulmonary and myocardial single photon emission computed tomography

    Författare :Helén Almquist; Lund Klinisk fysiologi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Klinisk fysiologi; tomography; medical instrumentation; radiology; Clinical physics; downscatter; myocardial perfustion; ventilation-perfusion ratio; radiologi; pulmonary density; pulmonary perfusion; attenuation correction; SPECT; transmission measurement; tomografi; medicinsk instrumentering;

    Sammanfattning : The objective was to develop and validate methods for single photon emission computed tomography, SPECT, allowing quantitative physiological and diagnostic studies of lung and heart. A method for correction of variable attenuation in SPECT, based on transmission measurements before administration of an isotope to the subject, was developed and evaluated. LÄS MER

  4. 4. Gas Exchange in the Normal Lung : Experimental studies on the effects of positive end-expiratory pressure and body position

    Författare :Mats J. Johansson; Sten Walther; Gunnar Nicolaysen; John-Peder Escobar Kvitting; Stefan Lundin; Linköpings universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES;

    Sammanfattning : BACKGROUND: The principal function of the lung is gas exchange requiring adequate ventilation and perfusion at the level of the alveoli. The efficiency of gas exchange is depending on the distributions of regional ventilation (V) and pulmonary blood flow (Q) and their correlation. LÄS MER

  5. 5. The bone cement implantation syndrome - epidemiology, pathophysiology and prevention

    Författare :Mathias Hård af Segerstad; Göteborgs universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; bone cement implantation syndrome; femoral neck fracture; cemented hip hemiarthroplasty; pulmonary haemodynamic; right ventricle ejection fraction; pulmonary vascular resistance; hemiarthroplasty;

    Sammanfattning : Bone cementation implantation syndrome (BCIS) has significant morbidity and mortality for patients who are undergoing cemented hip hemiarthroplasty or arthroplasty. The aim of this thesis is to contribute with information of the epidemiological parameters of BCIS and identify risk factors. LÄS MER