ABSTRACT
Venovenous extracorporeal membrane oxygenation (VV-ECMO) is a useful life support in severe acute respiratory distress syndrome (ARDS). Although prolonged mechanical ventilation (MV) before institution of ECMO is known to be a poor prognostic factor for outcomes of VV-ECMO, a reasonable deadline for this period has not been defined yet. To discover the answer, we reviewed a 9 year institutional experience of adult respiratory ECMO in VV configuration and investigate the relationship between the MV time before ECMO and in-hospital mortality. This retrospective study included 129 adult patients receiving VV-ECMO for ARDS in a single institution from 2007 to 2016. Important demographic and clinical data before ECMO intervention were collected for analyses of in-hospital mortality. The MV time before ECMO independently predicted hospital death in adult respiratory ECMO here. While compared to the patients receiving MV for 7 days or less, the patients receiving MV for more than 7 days before ECMO showed a higher in-hospital mortality rate (77% vs. 38%, p < 0.001). They also experienced a more significant deterioration in respiratory function during MV before the institution of ECMO. Therefore, from the clinical observation, we thought that a 7 day period might be an acceptable limit on MV time before institution of VV-ECMO. Integrating other respiratory parameters into the current PaO2/FiO2 (PF) ratio-based inclusion criteria of adult respiratory ECMO might be helpful to reduce the risk of prolonged MV in selected patients.
Subject(s)
Extracorporeal Membrane Oxygenation , Respiration, Artificial , Respiratory Distress Syndrome/therapy , Adult , Aged , Extracorporeal Membrane Oxygenation/mortality , Female , Hospital Mortality , Humans , Male , Middle Aged , Respiration , Respiratory Distress Syndrome/mortality , Retrospective Studies , Time FactorsABSTRACT
Despite a therapeutic option for severe acute respiratory distress syndrome (ARDS), the survival benefit of venovenous extracorporeal membrane oxygenation (VV-ECMO) is still controversial in adults. This study was aimed at investigating the prognostic factors for ECMO-treated ARDS in adult patients.From 2012 to 2015, 49 patients (median age: 57 years) received VV-ECMO in our institution and were included in this retrospective study. The indication of VV-ECMO was a severe hypoxemia (PaO2/FiO2 ratio <70âmmHg) under mechanical ventilation (MV) with a peak inspiratory pressure (PIP) >35âcmH2O and a FiO2 >0.8. To decrease the impact of pulmonary injuries associated with the high-pressure ventilation, the settings of MV on VV-ECMO were downgraded according to our protocol. Outcomes of this study were death on VV-ECMO and death in hospital. Important demographic and clinical data during the treatment were collected for outcome analyses.All patients experienced significant improvements in arterial oxygenation on VV-ECMO. Twenty-four hours after initiation of VV-ECMO, the median PaO2/FiO2 ratio increased from 58 to 172âmmHg (Pâ<â0.001) and the median SaO2 increased from 86% to 97% (Pâ<â0.001). In the meantime, the MV settings were also effectively downgraded. The median PIP decreased from 35 to 29âcmH2O (Pâ<â0.001) and the median tidal volume decreased from 7 to 5âml/kg/min (Pâ<â0.001). Twelve patients died during the treatment of VV-ECMO and 21 patients died before hospital discharge. Among all of the pre-ECMO variables, the pre-ECMO pulmonary dynamic compliance (PCdyn) <20âmL/cmH2O was identified to be the prognostic factor of death on VV-ECMO (odds ratio [OR]: 6, 95% confidence interval [CI]: 1-35, Pâ=â0.03), and the pre-ECMO duration of MV >90âhours was the prognostic factor of death before hospital discharge (OR: 7, 95% CI: 1-29, Pâ=â0.01).VV-ECMO was a useful salvage therapy for severe ARDS in adults. However, the value of PCdyn and the duration of MV before intervention with VV-ECMO may significantly affect the patients' outcomes.