Effect Of Different Positive End-expiratory Pressure Levels On The Patients With Severe ARDS

Objectives To observe and compare the effect of different levels of PEEP in the treatment of invasive mechanical ventilation of patients with severe ARDS,and to provide reference for the selection of ventilator parameters for patients.Methods 160 patients with severe ARDS admitted to the ICU in the Hospital of North China University of Science and Technology from October 2015 to December 2020 were collected as the research subjects,including endogenous pulmonary ARDS（ARDSp,n=72）and exogenous pulmonary ARDS（ARDSexp,n=88）.Then according to the PEEP level（5cm H₂O,10cm H₂O,15cm H₂O,20cm H₂O）,ARDSp was divided into N1,N2,N3 and N4group,with 18 cases in each group,and ARDSexp was divided into W1,W2,W3 and W4group,with 22 cases in each group.To observe and compare two types patients of each group with mechanical ventilation before（T0）,after mechanical ventilation parameter and stable30 min（T1）,6 h（T2）,12 h（T3）,24 h（T4）,48 h（T5）at the same time different group of arterial blood gas analysis index(PH,Pa CO₂,Pa O₂,Pa O₂/Fi O_2,c Lac),hemodynamic indexes（HR,MAP,CVP）,T1-T5 respiratory mechanics index（Ppeak,Raw,Cst）,and corresponding index change in the same group of different points.The time of invasive mechanical ventilation,indwelling time of endotracheal catheter and ICU hospitalization time of the patients were recorded and compared.Results There were no significant differences in gender,age,BMI,onset time and APACHEⅡscore on the day of diagnosis among different groups of ARDSp and ARDSexp（P>0.05）.Comparison within groups:PH and c Lac at T1-T5 were lower than those at T0,and Pa CO₂,Pa O₂,Pa O₂/Fi O₂,MAP,HR,CVP were higher than those at T0;Ppeak and Raw at T2-T5 were lower than those at T1,while Cst were higher than those at T1,with statistical significance（P<0.05）.Comparison between groups:in ARDSp and ARDSexp patients,Pa O₂ and Pa O₂/Fi O₂ increased with PEEP increasing after T2 and T1respectively,and increased significantly at 15cm H₂O in ARDSp and 10cm H₂O in ARDSexp patients respectively,with statistical significance（P<0.05）,and at T3-T5,Cst increased significantly when PEEP was 15cm H₂O and 10cm H₂O respectively while the mechanical ventilation time,endotracheal intubation indwelling time and ICU stay time were shortened when the PEEP was 15cm H₂O and 10cm H₂O respectively,with statistical significance（P<0.05）.The changes of PH,Pa CO₂ and MAP in different groups at the same time were not statistically significant in all patients（P>0.05）.At T1-T5,Ppeak increased with the increase of PEEP,while at T3-T5,when PEEP was higher than 15 cm H₂O,HR,CVP and Raw increased significantly,and c Lac decreased significantly,and the difference was statistically significant（P<0.05）.Conclusions Patients with severe ARDSp and severe ARDSexp has better prognosis when PEEP is 15cm H₂O and 10cm H₂O respectively.Figure 0;Table8;Reference 151...