A novel extracorporeal CO(2) removal system: results of a pilot study of hypercapnic respiratory failure in patients with COPD

Abstract

Background: Hypercapnic respiratory failure in patients with COPD frequently requires mechanical ventilatory support. Extracorporeal CO2 removal (ECCO2R) techniques have not been systematically evaluated in these patients.

Methods: This is a pilot study of a novel ECCO2R device that utilizes a single venous catheter with high CO2 removal rates at low blood flows. Twenty hypercapnic patients with COPD received ECCO2R. Group 1 (n = 7) consisted of patients receiving noninvasive ventilation with a high likelihood of requiring invasive ventilation, group 2 (n = 2) consisted of patients who could not be weaned from noninvasive ventilation, and group 3 (n = 11) consisted of patients on invasive ventilation who had failed attempts to wean.

Results: The device was well tolerated, with complications and rates similar to those seen with central venous catheterization. Blood flow through the system was 430.5 ± 73.7 mL/min, and ECCO2R was 82.5 ± 15.6 mL/min and did not change significantly with time. Invasive ventilation was avoided in all patients in group 1 and both patients in group 2 were weaned; PaCO2 decreased significantly (P < .003) with application of the device from 78.9 ± 16.8 mm Hg to 65.9 ± 11.5 mm Hg. In group 3, three patients were weaned, while the level of invasive ventilatory support was reduced in three patients. One patient in group 3 died due to a retroperitoneal bleed following catheterization.

Conclusions: This single-catheter, low-flow ECCO2R system provided clinically useful levels of CO2 removal in these patients with COPD. The system appears to be a potentially valuable additional modality for the treatment of hypercapnic respiratory failure.

Trial registration: ClinicalTrials.gov NCT00987740 NCT01021605.

Figures

Figure 1.

The Hemolung15.5F double-lumen extracorporeal CO2 removal (ECCO2R) catheter with an optional femoral or jugular configuration.

Figure 2.

Blood flow (mean ± SEM) and CO2 removal (mean ± SEM) through the catheter over time, where n = number of subjects at various time points.

Figure 3.

Changes in PaCO2 (mean ± SEM) and pH (mean ± SEM) with ECCO2R in patients in group 1 (acute exacerbation of COPD on noninvasive positive pressure ventilation [NIPPV]). n = number of subjects; 0 h on abscissa represents baseline values. See Figure 1 legend for expansion of other abbreviations.