79 (CI95: 0.52 to 0.94) otherwise (P = 0.07), with a marked decrease of the visual overlap of baseline values of ��RESPPP between responders and nonresponders Vandetanib (Figure (Figure4A).4A). Dividing our whole population according to the median value of airway driving pressure (10 cmH2O) did not lead to marked difference in AUC and/or in the visual overlap (Figure (Figure4B4B).Figure 4Individual values of baseline ��RESPPP according to volume responsiveness status and to either respiratory change in PAOP (��PAOP) or airway driving pressure. For the purpose of this physiological analysis, patients with ultrasonographic …Overall, ��RESPPP performed similarly in the subgroups of patients according to respiratory system compliance, norepinephrine dosage, administration of neuromuscular blocking agents (n = 26), site of the arterial catheter (radial (n = 14) or femoral (n = 51)) (Additional file 1).

SPV (n = 65), dDown (n = 45), CVP (n = 65), PAOP (n = 33) and PAOPtm (n = 33) were associated with an AUC below 0.78 (Figure (Figure2).2). All the results were similar when using a 15% relative or a 300 ml/min/m2 absolute cutoff for volume expansion-induced increase in CO to define fluid responsiveness (Table (Table33 and Additional file 1, Figures S1 and S2). Among the 40 patients whose CVP increased by ��2 mmHg after 300-ml fluid loading, none of the 28 nonresponders after 300 ml responded to the additional 200-ml fluid loading.DiscussionThe main finding of this large multicenter study of 65 shocked ARDS patients with neither arrhythmia nor spontaneous respiratory activity is that the performance of ��RESPPP is poor in this clinical situation.

Because fluid responsiveness prediction is of utmost importance in ARDS, we attempted unsuccessfully to improve ��RESPPP performance by (1) its indexation, (2) analyzing different cutoffs for ��RESPPP or fluid responsiveness definition or (3) identifying subgroups where ��RESPPP may perform better.Huang et al.’s study [17], including 22 patients, specifically addressed the issue of ��RESPPP performance in ARDS and reported a similar AUC (0.77) for ��RESPPP as in our population (0.75 (CI95: 0.62 to 0.085)). In our study, the AUC was not good, as the lower bound of the 95% confidence interval was below 0.75 [27]. Partly because confidence intervals for AUCs were not reported in Huang et al.

‘s study [17], it was considered that these authors’ conclusion (that ��RESPPP remains a reliable predictor of fluid responsiveness for ARDS patients ventilated with low Vt and high PEEP) was a misinterpretation [28,29]. In a large, multicenter population of ARDS patients, our results are similar Entinostat to those of De Backer et al. [10], who found, in 33 patients (97% ARDS patients) receiving Vt <8 ml/kg, that ��RESPPP did not perform better than PAOP. Other authors also observed this low performance of ��RESPPP in case of low Vt.