Pro-inflammatory cytokine levels. In the second set of experiments IL-6 and KC levels in the BAL fluid were highest in the PEEP6_noRM group, followed by the PEEP6_RM5 group (Fig. 11A, B) . Both mediators were lowest in the PEEP6_noRM group. IL-6 in the blood serum was not significantly different between these three groups (Fig. 11C) . KC levels were highest in the group ventilated without RM, but differed only slightly between the groups ventilated with RM5 and RM60 Fig. 11D ).