Prone Position in Acute Respiratory Failure :Responsiveness and Changes in Chest Radiographic Pattern

초록

목적:The prone position is increasingly applied to the treatment of acute respiratory distress syndrome (ARDS). Although, the recruitment of dorsal lung units and decreased V/Q mismatching is the main reason why prone positioning improves gas exchange, the exact mechanism and the reasonable methods predicting responsiveness are not completely revealed. We analyzed and compared the chest radiographic patterns between the responsive group and unresponsive group. 방법:We reviewed the supine and prone chest radiographs of 41 patients who were diagnosed with ARDS. On supine and prone chest radiographs, we scored the presence and extent of each finding (ground-glass opacity, consolidation, reticular opacity, pleural effusion, and obliteration of cardiac and paraspinal borders). PaO2/FiO2 ratio increased by more than 20% after prone position, in 24 patients (responsive group). PaO2/FiO2 ratio decreased or increased by less than 20% in 17 patients (unresponsive group). Provoking causes of ARDS were pulmonary disease in 29 patients, and extrapulmonary diseases in 12 patients. 결과:The extent of ground-glass opacity of both group slightly decreased on prone position in 55% of patients, but reticular opacities did not resolve in 71%. The consolidation in extrapulmonary ARDS tended to resolve completely (82%), but the consolidation in pulmonary ARDS was persistent or progressed even in prone position (75%). The obscured borders of both paravertebral stripes and descending aorta on supine chest radiographs changed to more recognizable lines on prone chest radiographs of responsive group (71%) than on prone chest radiographs of unresponsive group (35%) (p=0.023). However, the change of the obliterated cardiac borders did not show any difference between two groups. All of five patients with pleural effusion did not respond to prone position. 결론: The posterior mediastinal borders are more recognizable in responsive group. These findings correspond to the recruitment o