Impairment of lung and chest wall mechanics in patients with acute respiratory distress syndrome: role of abdominal distension. Am.J Respir.Crit Care Med. 156

Recent data have suggested that the elastic properties of the chest wall (CW) may be compromised in patients with ARDS because of abdominal distension (4). We partitioned CW and lung (L) mechan-ics, assessed the role of abdominal distension, and verified whether the underlying disease responsi-ble for ARDS affects the impairment of respiratory mechanics. Volume-pressure (V-P) curves (inter-rupter technique) were assessed in nine patients with surgical ARDS and nine patients with medical ARDS. Relative to nine patients undergoing heart surgery, V-P curves of the respiratory system (rs) and L of patients with surgical or medical ARDS showed a rightward displacement. V-P curves of the CW and the L showed an upward concavity in patients with medical ARDS and a downward concavity in patients with surgical ARDS. Although the CW and the abdomen (abd) V-P curves in patients with medical ARDS were similar to those obtained in patients undergoing heart surgery, they showed a rightward shift and a downward flattening in patients with surgical ARDS. In five of these patients, a reduction in static end-inspiratory pressure of the abd (69