A 2-year multicenter, observational, prospective, cohort study on extracorporeal CO2 removal in a large metropolis area

Background

Extracorporeal carbon dioxide removal (ECCO₂R) is a promising technique for the management of acute respiratory failure, but with a limited level of evidence to support its use outside clinical trials and/or data collection initiatives. We report a collaborative initiative in a large metropolis.

Methods

To assess on a structural basis the rate of utilization as well as efficacy and safety parameters of 2 ECCO₂R devices in 10 intensive care units (ICU) during a 2-year period.

Results

Seventy patients were recruited in 10 voluntary and specifically trained centers. The median utilization rate was 0.19 patient/month/center (min 0.04; max 1.20). ECCO₂R was started under invasive mechanical ventilation (IMV) in 59 patients and non-invasive ventilation in 11 patients. The Hemolung Respiratory Assist System (Alung) was used in 53 patients and the iLA Activve iLA kit (Xenios Novalung) in 17 patients. Main indications were ultraprotective ventilation for ARDS patients (n = 24), shortening the duration of IMV in COPD patients (n = 21), preventing intubation in COPD patients (n = 9), and controlling hypercapnia and dynamic hyperinflation in mechanically ventilated patients with severe acute asthma (n = 6). A reduction in median V_T was observed in ARDS patients from 5.9 to 4.1 ml/kg (p <0.001). A reduction in PaCO₂ values was observed in AE-COPD patients from 67.5 to 51 mmHg (p< 0.001). Median duration of ECCO₂R was 5 days (IQR 3–8). Reasons for ECCO₂R discontinuation were improvement (n = 33), ECCO₂R-related complications (n = 18), limitation of life-sustaining therapies or measures decision (n = 10), and death (n = 9). Main adverse events were hemolysis (n = 21), bleeding (n = 17), and lung membrane clotting (n = 11), with different profiles between the devices. Thirty-five deaths occurred during the ICU stay, 3 of which being ECCO₂R-related.

Conclusions

Based on a registry, we report a low rate of ECCO₂R device utilization, mainly in severe COPD and ARDS patients. Physiological efficacy was confirmed in these two populations. We confirmed safety concerns such as hemolysis, bleeding, and thrombosis, with different profiles between the devices. Such results could help to design future studies aiming to enhance safety, to demonstrate a still-lacking strong clinical benefit of ECCO₂R, and to guide the choice between different devices.