View clinical trials related to Pulmonary Atelectasis.
Filter by:The purpose of this study is to measure the density of a temperature-sensitive protein, named TRPV1, in the airway mucosa tissue of both non-asthmatic and moderate to severe persistent asthmatic patients. This study may generate information for developing new therapeutic strategy.
During most types of heart surgery cardiopulmonary bypass (CPB) is used. CPB enables blood to be directed away from the heart and the lungs and pumped through the body while the heart is not beating. Surgery on the heart easier when it is not beating and bloodless area. Generally during CPB the lungs do not need to be ventilated, as no blood is flowing through the lungs and the body received oxygen from a machine (oxygenator) attached to the CPB pump. In this study we are investigating the difference in lung collapse after heart surgery in patient who did have their lungs ventilated during CPB, compared to patients who did not have their lungs ventilated during CPB. We will use lung ultrasound scans to determine the degree of lung collapse at various time periods before and after the heart surgery. We will also investigate if ventilation during CPB will affect: a.) the rate of lung infection or pneumonia after the operation b.) the time it takes for a patient to have the breathing tube removed in the intensive care unit after the operation c.) the time for a patient to be discharged home from the hospital d.) the concentration of oxygen in the blood after the operation.
Even though experimental lung injury in animal experiments is the best analogy for the changes in the patients, it has to be considered that kinetics may vary between species. An important question to answer is how common PaO2-oscillations occur in patients and how injurious they might be. A limitation to the detection of PaO2-oscillations is a sensing device that detects the oscillations at very high temporal resolution. In previous studies a fiberoptic probe was used, which was measuring PaO2 based on oxygen-sensitive fluorescence quenching with a time resolution up to 10 Hz (8, 13, 14). This method is not feasible in patients. Previous studies have shown that PaO2-oscillations are translated into the peripheral hemoglobin oxygen saturation (SpO2). Given a technology that has a time resolution that is high enough (i.e. >1 Hz), measurement of SpO2-oscillations would be a valid approach to detecting and quantifying cyclical recruitment and derecruitment in a non-invasive fashion in patients on the ICU. The Masimo Rad-8 pulse-oxymeter provides such a method. In the current study it is planned to deteted SpO2-oscillations in the post-operative patients on the ICU.
Atelectasis is common during and after general anesthesia. The investigators hypothesized that a ventilation strategy with a combination of 1) continuous positive airway pressure (CPAP) or positive end-expiratory pressure (PEEP) and 2) a reduced end-expiratory oxygen fraction (FETO2) before commencing mask ventilation with CPAP after extubation would reduce the area of postoperative atelectasis.