Control of respiratory drive by extracorporeal CO removal in acute exacerbation of COPD breathing on non-invasive NAVA.

BACKGROUND

Veno-venous extracorporeal CO removal (vv-ECCOR) and non-invasive neurally adjusted ventilator assist (NIV-NAVA) are two promising techniques which may prevent complications related to prolonged invasive mechanical ventilation in patients with acute exacerbation of COPD.

METHODS

A physiological study of the electrical activity of the diaphragm (Edi) response was conducted with varying degrees of extracorporeal CO removal to control the respiratory drive in patients with severe acute exacerbation of COPD breathing on NIV-NAVA.

RESULTS

Twenty COPD patients (SAPS II 37 ± 5.6, age 57 ± 9 years) treated with vv-ECCOR and supported by NIV-NAVA were studied during stepwise weaning of vv-ECCOR. Based on dyspnea, tolerance, and blood gases, weaning from vv-ECCOR was successful in 12 and failed in eight patients. Respiratory drive (measured via the Edi) increased to 19 ± 10 μV vs. 56 ± 20 μV in the successful and unsuccessful weaning groups, respectively, resulting in all patients keeping their CO and pH values stable. Edi was the best predictor for vv-ECCOR weaning failure (ROC analysis AUC 0.95), whereas respiratory rate, rapid shallow breathing index, and tidal volume had lower predictive values. Eventually, 19 patients were discharged home, while one patient died. Mortality at 90 days and 180 days was 15 and 25%, respectively.

CONCLUSIONS

This study demonstrates for the first time the usefulness of the Edi signal to monitor and guide patients with severe acute exacerbation of COPD on vv-ECCOR and NIV-NAVA. The Edi during vv-ECCOR weaning was found to be the best predictor of tolerance to removing vv-ECCOR.