Dual lumen catheter cannulation for venovenous ECMO

Dear Editor, The recent availability of the Avalon Elite bicaval dual lumen catheter offers a potentially less invasive approach for the extracorporeal membrane oxygenation (ECMO) treatment of severe respiratory insufficiency as compared to the femorojugular approach [1]. Nevertheless, Avalon cannula placement is more demanding and no data have been published about its effectiveness in improving oxygenation and safety concerning hemolysis, which is also an important issue, being reported in 27 % of ECMO patients [2]. In the last 2 years, we systematically adopted the bicaval dual lumen jugular approach for venovenous (VV)-ECMO treatment. Data about oxygenation and hemolysis have been collected and compared with an historical group of patients treated with the femorojugular approach (Table 1). Patients were supported with ECMO in case of severe hypoxia refractory to conventional treatment. During cannulation and 6 h after, patients were sedated. After cannulation, a respiratory rate of 10 breaths per minute, a 40 % FiO2, and a maximum tidal volume of 6 ml/kg were established. Early awakening with spontaneous ventilation and mobilization was attempted whenever possible. All recent patients were cannulated with an Avalon Elite bicaval dual lumen catheter 27 or 31 Fr under transesophageal echocardiography (TEE) imaging. No complications were observed during the procedure and all patients underwent a correct cannula placement. Moreover, most of the patients were extubated and mobilized before ECMO removal, without any issue on the cannula. Similarly, the previously used femorojugular approach with an HLS cannulae set (15–19 and 21–25 Fr) showed a correct placement under TEE imaging and no complications related to the procedure. Data in Table 1 about gas exchange refer to the first 6 h of VVECMO treatment. We considered blood flow as the major determinant of oxygenation [3]. Hemolysis was observed during the VV-ECMO support, and peak values of free hemoglobin and lactic dehydrogenase are reported. At similar pump flow (mean 3.3 vs 3.6 l/min, P = 0.106), no significant difference was observed in oxygenation parameters and hemolysis in the two groups. In our view, we cannot identify any drawbacks to the use of the Avalon Elite bicaval dual lumen catheter for VV-ECMO because oxygenation improvement and hemolysis parameters were similar to those observed with the femorojugular approach. In the light of these data, we advise that TEE-guided Avalon Elite bicaval dual lumen catheter implantation is safe and, as it allows for safe mobilization (either for