Extracorporeal membrane oxygenation (ECMO) plays a significant role in the management of severe acute respiratory distress syndrome (ARDS) when conventional mechanical ventilation fails to maintain adequate oxygenation and ventilation.
Indications for ECMO in ARDS
- The British Thoracic Society (BTS) 2019 guidelines suggest ECMO with lung-protective mechanical ventilation in selected patients with severe ARDS, defined by a lung injury score ≥ 3 or pH < 7.20 due to uncompensated hypercapnia
- The Surviving Sepsis Campaign (SSC) 2021 guidelines recommend initiating venovenous ECMO in adult patients with sepsis-induced severe ARDS when conventional mechanical ventilation fails
- The Japanese Society of Intensive Care Medicine/Japanese Society of Respiratory Care Medicine (JSICM/JSRCM) 2022 guidelines recommend initiating ECMO in adult patients with severe ARDS
- The European Society of Intensive Care Medicine (ESICM) 2023 guidelines recommend initiating ECMO in patients with severe ARDS not due to COVID-19, as defined by the EOLIA trial eligibility criteria, in a specialized center meeting defined organizational standards. They also suggest ECMO in patients with severe ARDS due to COVID-19
Efficacy of ECMO in ARDS
- ECMO has been shown to significantly reduce in-hospital mortality in COVID-19-associated ARDS, which may be related to advances in ECMO-related techniques and increased clinician experience
- A systematic review and meta-analysis found that ECMO can provide a safe and effective alternative to lung-protective mechanical ventilation in carefully selected patients, facilitating participation in physical therapy and avoiding complications associated with mechanical ventilation
- ECMO has been used as a salvage treatment for patients with severe ARDS caused by SARS-CoV-2 pneumonia, with severe CO2 retention and acidosis prior to ECMO indicating a poor prognosis
Risks and complications of ECMO in ARDS
- ECMO is associated with risks such as bleeding, thrombosis, and infection, making patient selection critical.
- The use of ECMO can meaningfully increase the incidence of bleeding complications
- ECMO is frequently associated with significant complications such as bleeding and nosocomial infections
Economic evaluation of ECMO in ARDS
- Based on current data, venovenous ECMO is cost-effective for patients with severe ARDS. However, additional evidence on the efficacy of venovenous ECMO for ARDS and in different subgroups of patients will allow for greater certainty in its cost-effectiveness
In conclusion, ECMO plays a crucial role in the management of severe ARDS, particularly when conventional mechanical ventilation fails. However, due to the associated risks and complications, careful patient selection and management in specialized centers are essential.