Effects of recruitment maneuvers on biomarkers and electrical impedance tomography in lung injury

• Main Authors: Yu, Hsiao-Min, 游小旻
• Other Authors: Chang, Hung
• Format: Others
• Language: zh-TW
• Published: 2017
• Online Access: http://ndltd.ncl.edu.tw/handle/10025373334615136632

碩士 === 國防醫學院 === 生理學研究所 === 105 === Backgrounds: Acute lung injury (ALI) is characterized by diffuse alveolar epithelial and endothelial injury leading to increased alveolar surface tension and atelectasis with resulting hypoxemia .One current ventilator strategy for patients with ALI includes recruitment maneuver (RM). RM with high positive-end expiratory pressure (PEEP) aims to open atelectatic alveoli, but improper ventilator settings may lead to high transpulmonary pressures which induce or aggravate lung injury. In this study, we investigated the global and regional ventilation and inflammation with non-invasive tools by electrical impedance tomography (EIT) and exhaled breath condensate (EBC) in a porcine model of ALI and effects of RM.Methods: Lung injury was induced with Tween-20, which randomized to into three groups: control group, ALI group and ALI with RM group. RM was applied by increasing the PEEP in a stepwise fashion first to 10 cm H2O (3 breaths), then to 15 cm H2O (3 breaths), and finally to 20 cm H2O (10 breaths) with peak inspiratory pressures up to 50 cm H2O. Regional ventilation during tidal breathing were identified in EIT images. ECB obtained lower respiratory tract samples that represent the composition of the alveolar lining fluid.Results: Arterial oxygen content (CaO2), ratio of PaO2 to inspiratory oxygen concentration (PaO2/FiO2), intrapulmonary shunt (Qs/Qt), partial pressure of carbon dioxide (PaCO2), pulmonary vascular resistance index (PVRI), respiratory system compliance (Crs) were significantly improved in the ALI+RM group. Cytokines in EBC revealed increase level of Interleukin (IL)-1β and IL-6 in the ALI+RM group. Cytokines in serum revealed increase level of IL-1β and IL-6 in the ALI and ALI+RMgroup. Cytokines in BALF revealed increase level of IL-1β, IL-6 and TNF-α in the ALI and ALI+RMgroup. Alveolar exudate were increased in the ALI group and ALI+RM group. Higher global inhomogeneity index (GI) and center of ventilation (CoV) value during RM. MicroRNA (miRNA) revealed increase level of miR-449b-3p, miR-144-5p, miR-451a, miR-449b-5p in the ALI and ALI+RMgroup.Conclusion: RM results in increased oxygenation, but did not improved the degree of lung tissue injury.