Differences in PaO
ratio, CDP and OI insurvivors (open circles) and non-survivors (filled circles). X-axisindicates time (hours) on HFOV. Baseline is the time on CMV immediatelypreceding the change to HFOV. 'Last' is the last measurement on HFOV prior toreturning to CMV. A: Differences PaO2/FiO2 ratioover time between survivors (open circles) versus non-survivors (filledcircles). B: Trends of change in CDP between survivors andnon-survivors. Data are displayed as mean and error bars represent SEM at eachtime-point. The number of patients (survivors - S; and non-survivors -NS) atdifferent time- points were: at baseline (S, n = 45; NS, n =57); 12 hours (S, n = 44; NS, n = 38); 24 hours (S, n = 39; NS, n = 28); 48 hours (S, n = 31; NS, n =24); 72 hours(S, n = 25; NS, n = 19). * = P <0.01- comparisons at each timepoint versus baseline. CDP, continuousdistending pressure; CMV, conventional mechanical ventilation; FiO2, fraction of inspired oxygen; HFOV, high-frequency oscillatoryventilation; SEM, standard error of the mean.