Individualization of Positive End-Expiratory Pressure Setting in Patients with Acute Respiratory Distress Syndrome under Extracorporeal Membrane Oxygenation Inputs from Electrical Impedance Tomography

摘要

In the most severe cases of acute respiratory distress syndrome (ARDS), extracorporeal membrane oxygenation (ECMO) can be a life-saving supportive therapy. Some countries use ECMO at a high rate (1), but overall it was shown that the setting of the concomitant ventilator support is not standardized (2-4). The overall goal of mechanical ventilation under ECMO is to rest the lung by using low (and even very low) tidal volume and low respiratory rate, and to maintain sufficient positive end-expiratory pressure (PEEP). These settings aim at minimizing dynamic strain (5) and mechanical power generated against the lung (6). The issue of PEEP setting is, however, still a matter of debate whether or not patients are receiving ECMO. In patients with ARDS under ECMO, the median PEEP reported so far was close to 12 cm H_2O, with 25% of the patients receiving a level greater than 14.5 cm H_2O (2-4). The rationale for setting PEEP in patients with ARDS under ECMO is uncertain because the pathophysiological characteristics of the ARDS lung are largely unknown and no specific strategies/targets have been rigorously tested in this setting. Furthermore, there is a strong will to personalize therapeutic approaches in medicine in general and this applies as well to patients in the intensive care unit. This is particularly important in a condition like ARDS where a large heterogeneity exists across the patients.