Effects Of End-expiratory Transpulmonary Pressure Changes On Oxygenation And Respiratory Mechanics In ARDS Patients

Purpose:To determine the optimal end-expiratory transpulmonary pressure?PtpPEEP?for improving oxygenation and lung compliance in patients with ARDS.Methods:A prospective self-control study was conducted.Sixteen patients with acute respiratory distress syndrome?ARDS?undergoing mechanical ventilation?defined within36 hours after diagnosis?were enrolled in the Department of Critical Care Medicine?ICU?,the First Affiliated Hospital of Xinjiang Medical University from December 2016 to October 2017.After adequate lung recruitment was given,the head of the bed was raised30 degrees,placed into the esophageal varicose vein after adequate sedation and analgesia,and the PEEP value was gradually increased to maintain PtpPEEP separately by positive end expiratory pressure?PEEP?At 3cmH₂O,6cmH₂O and 9cmH₂O levels,PtpPlat<25cmH₂O was monitored at the same time and ventilated for 1 hour respectively.To observe the optimal level of PtpPEEP with oxygenation and respiration mechanics improvement on ARDS patients.Result:A total of 16 patients with ARDS were enrolled in this study.There were 9 males and 7 females,mean age?58.7±14.2 years?,APACHE?score?20.3±3.7?,when PtpPEEP was 3cmH₂O,oxygenation index?PaO₂/FiO₂?was?140.5±41.9?mmHg?1mmHg=0.133 kPa?.PEEP was?11.5±2.4?cmH₂O;PaO₂/FiO₂?258±72mmHg?and?50±8?ml/cmH₂O was observed for static pulmonary compliance.PEEP was?17.1±2.5?cmH₂O when PtpPEEP was 6cmH₂O;PaO₂/FiO₂?289±99mmHg?and?41±9?ml/cmH₂O was observed for static pulmonary compliance.PEEP was?22±2.6?cmH₂O when PtpPEEP was 9 cmH₂O;PaO₂/FiO₂?312±86mmHg?and?37±8?ml/cmH₂O was observed for static pulmonary compliance.There was no significant difference in improvement of PaO₂/FiO₂ between PtpPEEP of 3cmH₂O and 6cmH₂O;9cmH₂O of PtpPEEP of 3cmH₂O compared with basal state,PtpPEEP 6cmH₂O and 9cmH₂O.However,Compared with oxygenation significantly improved P<0.05.There was no significant differencein hemodynamic changes between groups.Conclusions:Maintaining PtpPEEP of 3 cmH₂O not only prevented alveolar collapse,but also improved oxygenation and lung compliance in ARDS patients with no significant effect on patient hemodynamics.