Prognostic Value Of The Driving Pressure In Patients During The Early Phase Of Acute Respiratory Distress Syndrome

Objective:To investigate the association between driving pressure and the prognosis of patients with early acute respiratory syndrome（ARDS）.Methods:A single center,prospective,observation study was performed.Patients with early ARDS（<3 days）with stable hemodynamics and under invasive mechanical ventilation were enrolled.The following baseline characteristics were recorded:age,gender,height,weight,etiology of ARDS,APACHEII score,Murray lung injury score,and the survival status of 28 days.The following blood gas parameters within24h after patient enrolled were collected:PH,PaCO2,PaO2/FiO2 ratio and arterial lactate level.Adequate sedation and analgesia were performed after patients included,All ARDS patients under lung protective ventilation,adjust mechanical ventilation parameters to reach a steady state of the blood oxygen saturation,the following parameters were:breathing rate,minute ventilation,tidal volume（TV）,PEEP,Pplat（inspiratory pause for 2 seconds to obtain platform pressure）,ΔP was calculated as Pplat minus PEEP.All included patients were followed up to 28 days and were classified into the survival group or the death group according to their clinical outcomes.Results:A total of 46 patients with early ARDS was enrolled.The death group included20 patients,the survival group included 26 patients.The 28-day mortality rate was43.5%.The mean value ofΔP for all ARDS patients was13.74±1.97cmH₂O.ΔP in the death group was significantly higher than that in the survival group[（15.30±2.26）VS.（12.85±1.05）,P<0.05].The areas under ROC curve（AUC）ofΔP for predicting28-day mortality was 0.843（P<0.05）,which was better than those of AUC of APACH II,Pplat and Murray score.Using aΔP cut-off value of>13.77cmH₂O to predict 28-day mortality,the sensitivity and specificity was 0.692 and 0.870,respectively.Conclusions:The ΔP level is significantly higher in the death group than that of the survival group.Compared with APACH II,Pplat and Murray score,ΔP is a better prognostic indicator for patients with early ARDS.TheΔP,age,APACHEII score were related with the 28-day moetality of ARDS patients.