Effects of positive end-expiratory pressure on hemodynamics and intra-abdominal pressure in patients with acute respiratory distress syndrome with and without intra-abdominal hypertension / 中华急诊医学杂志

ABSTRACT

Objective To investigate the effects of positive end-expiratory pressure (PEEP) on hemodynamics and intra-abdominal pressure in patients with acute respiratory distress syndrome (ARDS) with normal intra-abdominal pressure (IAP) and intra-abdominal hypertension (IAH) during mechanical ventilation under a incremental PEEP.Methods Eighteen ARDS patients with normal IAP or IAH treated in intensive care unit of Anhui Provincial Hospital were enrolled for study.At different PEEP levels (5,10,15,20 cmH2O),hemodynamic parameters including extravascular lung water index (EVLWI),intrathoracic blood volume index (ITBVI),stroke volume variation (SVV) and IAP were measured with PICCO technology.Results Compared with ARDS patients with normal IAP,the ARDS patients with IAH were characterized by(1) EVLWI was decreasing under the increment of PEEP,but there was no significant difference between 15 cmH2O and 20 cmH2O (t =0.593,P =0.572).As PEEP was gradually escalated,EWLVI had no significant changes in patients with normal IAP.(2) SVV increased as PEEP was being titrated to higher level in both groups but in normal IAP group such effect was observed till PEEP above 10cmH2O (PEEP5 vs.PEEP10,t=0.326,P=0.752; PEEP,10 vs.PEEP 15,t=-20.032,P＜ 0.01).(3) There was no statistical difference in ITBVI between two groups at varied levels of PEEP.(4) PEEP could increase IAP levels and had much more profound effects on patients with IAH.Conclusions PEEP is a contributing factor changing IAP.It is necessary to take the level of PEEP into account as IAP variation is interpreted in patients under mechanical ventilation.Different PEEP levels can significantly affect the EVLWI in patients with IAH but not do not in ones with nomal IAP.