Fig. 2
The impacts of positive end-expiratory pressure in animals with normovolemia and intracranial hypertension (Series II, n = 6 per group). Data were presented as mean and standard deviation. RM-ANOVA was used. The corresponding changes of mean arterial pressure were presented in grey lines (showing means only), solid line: control group, dash line: chest wall strapping group. A ICP significantly increased when PEEP was increased (p < 0.001 for both groups), and the magnitude was significantly higher in the chest wall strapping group than in the control group (p = 0.022). B PtiO2 significantly decreased when PEEP was increased (p < 0.001 for both groups), but the magnitude was similar between groups (p = 0.333). C CO significantly decreased with PEEP increment (p < 0.001 for both groups), while no difference was observed between groups (p = 0.649). D CPP significantly decreased with PEEP increment (p < 0.001 for both groups), no difference was observed between groups (p = 0.367). ICP intracranial pressure, PEEP positive end-expiratory pressure, PtiO2 brain tissue O2 tension, CO cardiac output, CPP cerebral perfusion pressure