Fig. 3

The top panels in this figure represent data from the patient cohort included in this study and the bottom panels represent data from animal studies comparing control animals to animals treated with endotoxin (i.e., LPS, lipopolysaccharide). The upper left panel compares PdiTw and Pimax values for noninfected patients (black symbols) to infected patients (red symbols). Both PdiTw and Pimax values for infected patients were significantly lower than values for noninfected patients, but the relative infection-induced reductions were substantially greater for twitch measurements than for Pimax levels. As a result, the Pimax/twitch ratio for noninfected patients was significantly lower than for infected patients (right top panel, ^*indicates a significant difference, p < 0.001). The same pattern of findings was observed for animal studies, with both diaphragm twitch and maximal force (i.e., force in response to150 Hz) for endotoxin-treated animals significantly lower than for control animals (left lower panel). In addition, the 150 Hz/twitch force ratio was significantly lower for control than for endotoxin-treated animals (p = 0.042). PdiTw transdiaphragmatic twitch pressure in response to bilateral magnetic stimulation of the phrenic nerves, Pimax maximum inspiratory pressure