In vitro characterization of PrismaLung+: a novel ECCO 2 R device

Background Invasive mechanical ventilation is lifesaving in the setting of severe acute respiratory failure but can cause ventilation-induced lung injury. Advances in extracorporeal CO 2 removal (ECCO 2 R) technologies may facilitate more protective lung ventilation in acute respiratory distress syndrome, and enable earlier weaning and/or avoid invasive mechanical ventilation entirely in chronic obstructive pulmonary disease exacerbations. We evaluated the in vitro CO 2 removal capacity of the novel PrismaLung+ ECCO 2 R device compared with two existing gas exchangers. Methods The in vitro CO 2 removal capacity of the PrismaLung+ (surface area 0.8 m 2 , Baxter) was compared with the PrismaLung (surface area 0.35 m 2 , Baxter) and A.L.ONE (surface area 1.35 m 2 , Eurosets) devices, using a closed-loop bovine blood–perfused extracorporeal circuit. The efficacy of each device was measured at varying pCO 2 inlet (p in CO 2 ) levels (45, 60, and 80 mmHg) and blood flow rates ( Q B ) of 200–450 mL/min; the PrismaLung+ and A.L.ONE devices were also tested at a Q B of 600 mL/min. The amount of CO 2 removed by each device was assessed by measurement of the CO 2 infused to maintain circuit equilibrium (CO 2 infusion method) and compared with measured CO 2 concentrations in the inlet and outlet of the CO 2 removal device (blood gas analysis method). Results The PrismaLung+ device performed similarly to the A.L.ONE device, with both devices demonstrating CO 2 removal rates ~ 50% greater than the PrismaLung device. CO 2 removal rates were 73 ± 4.0, 44 ± 2.5, and 72 ± 1.9 mL/min, for PrismaLung+, PrismaLung, and A.L.ONE, respectively, at Q B 300 mL/min and p in CO 2 45 mmHg. A Bland–Altman plot demonstrated that the CO 2 infusion method was comparable to the blood gas analysis method for calculating CO 2 removal. The resistance to blood flow across the test device, as measured by pressure drop, varied as a function of blood flow rate, and was greatest for PrismaLung and lowest for the A.L.ONE device. Conclusions The newly developed PrismaLung+ performed more effectively than PrismaLung, with performance of CO 2 removal comparable to A.L.ONE at the flow rates tested, despite the smaller membrane surface area of PrismaLung+ versus A.L.ONE. Clinical testing of PrismaLung+ is warranted to further characterize its performance.