Percutaneous extracorporeal arteriovenous CO2 removal for severe respiratory failure

Background. In previous animal studies, arteriovenous CO2 removal (AVCO2R) achieved significant reduction in ventilator pressures and improvement in the Pa 2 to fraction of inspired oxygen ratio during severe respiratory failure. For our initial clinical experience, 5 patients were approved for treatment of severe respiratory failure and CO2 retention to evaluate the feasibility and safety of percutaneous AVCO2R. Methods. Patients were anticoagulated with heparin (activated clotting time, 260 to 300 seconds), underwent percutaneous femoral cannulation (10F to 12F arterial and 12F to 15F venous catheters), and then were connected to a low-resistance, 2.5-m2 hollow-fiber oxygenator for 72 hours. Results. Mean AVCO2R flow at 24, 48, and 72 hours was 837.4 ± 73.9, 873 ± 83.6, and 750 ± 104.5 mL/min, respectively, with no vascular complications and no significant change in heart rate or mean arterial pressure. Removal of CO2 plateaued at an AVCO2R flow of 1086 mL/min with 208 mL/min CO2 removed. Average CO2 transfer at 24 and 48 hours was 142 ± 17 and 129 ± 16 mL/min. Use of AVCO2R allowed a significant decrease in minute ventilation from 7.2 ± 2.3 L/min at baseline to 3.4 ± 0.8 L/min at 24 hours. Conclusions. All patients survived the experimental period without adverse sequelae. Percutaneous AVCO2R can achieve approximately 70% CO2 removal in adults with severe respiratory failure and CO2 retention without hemodynamic compromise or instability.