Safety and Efficacy of a Novel Pneumatically Driven Extracorporeal Membrane Oxygenation Device

Abstract

Background: Extracorporeal membrane oxygenation (ECMO) is rapidly becoming a mainstream technology for lung or heart/lung support. Current ECMO devices mostly consist of a power-driven centrifugal pump and a dedicated oxygenator. We studied the safety and efficacy of a novel, fully pneumatically driven ECMO device, which could be used in both venovenous or venoarterial mode in an animal model.

Methods: Six healthy, awake sheep were treated with the Mobybox ECMO device (Hemovent, Aachen, Germany) over a 7-day period in a venovenous mode. Gas exchange, coagulation parameters, and safety were assessed.

Results: Using a blood flow rate of 2 L/min and a low sweep gas flow rate of 0.3 L/min, the PCO₂ ranged from 38 to 44 mm Hg pre oxygenator and dropped to 32 to 36 mm Hg post oxygenator, whereas the PaO₂ post oxygenator increased to 600 mm Hg. Higher levels of sweep gas flow resulted in cessation of spontaneous breathing in some animals, consistent with high-efficiency carbon dioxide removal; thus, the sweep gas flow rate was maintained at a low level. Platelets dropped from 177 ± 53/μL to 107 ± 28/μL on day 2, while returning to baseline by day 7 (180 ± 51/μL). Plasma-free hemoglobin remained low (2-9 mg/dL), whereas fibrinogen slightly increased, and then remained stable throughout the period. Neither the pump nor the oxygenator showed any visible clotting after 7 days.

Conclusions: The pneumatically driven ECMO device provided excellent safety and physiologic efficacy in a 7-day sheep experiment without visible clotting, hemolysis, or sustained reductions in fibrinogen or platelets.