eComment. Ambulatory veno-venous extracorporeal membrane oxygenation

We read with great interest the article by Nosotti et al. [1]. The authors presented their experience with the use of veno-venous extracorporeal membrane oxygenation (ECMO) in 11 patients with severe end-stage lung failure awaiting lung transplantation. Seven patients were awake, while 4 patients required invasive mechanical ventilation. The authors describe significant improvements in the 1-year survival rate in non-sedated patients. In addition, the authors found a tendency to shorter duration of mechanical ventilation, intensive care unit stay and overall in-hospital stay for spontaneous breathing patients on ECMO after lung transplantation.

Although we applaud the efforts of Nosotti et al. and recognize the value of ECMO in non-intubated patients to overcome the drawbacks of long-term mechanical ventilation, we believe that the use of the currently available dual-lumen Avalon Elite cannula (Avalon Laboratories, LLC, Los Angeles, CA, USA) offers many advantages in awake, spontaneously breathing patients and should be the preferred approach for patients with acute respiratory failure, and for those being considered for a bridge-to-lung transplantation [2, 3]. Traditional veno-venous ECMO uses a two-cannula technique that requires bed rest and, in most circumstances, necessitates the patient to remain sedated and mechanically ventilated. The Avalon Elite cannula is the first Food and Drug Administration-approved device for single-site veno-venous ECMO in adults. The catheter is usually inserted into the right jugular vein and has 2 lumens; one lumen drains deoxygenated blood from the superior and inferior vena cava, and the other lumen returns oxygenated blood to the right atrium. Due to its unique design, this single-site cannula avoids recirculation of blood and increases the efficacy of ECMO. Additional advantages include not only the possibility to extubate the patient but also to permit ambulation. By allowing the patient to ambulate and to participate in physical therapy, the risk of ventilator-associated pneumonia and deconditioning is significantly decreased [4].

To further reduce the inconvenience of the cannula for awake patients, Shafii et al. described an alternative site to implant the Avalon Elite cannula [5]. Through the left subclavian vein and under fluoroscopic guidance, the cannula can be securely introduced and positioned. The subclavian access was shown to be more comfortable for patient ambulation and easier for nursing care.

In patients requiring prolonged support and specifically for those bridged to lung transplant, veno-venous ECMO with single site cannulation can be an excellent alternative to current cannulation strategies.

Conflict of interest: none declared