title: Extracorporeal CO2 Removal by Respiratory Electrodialysis: An In Vitro Study.
abstract: We previously described a highly efficient extracorporeal CO2 removal technique called respiratory electrodialysis (R-ED). Respiratory electrodialysis was composed of a hemodiafilter and a membrane lung (ML) positioned along the extracorporeal blood circuit, and an electrodialysis (ED) cell positioned on the hemodiafiltrate. The ED regionally increased blood chloride concentration to convert bicarbonate to CO2 upstream the ML, thus enhancing ML CO2 extraction (VCO2ML). In this in vitro study, with an aqueous polyelectrolytic carbonated solution mimicking blood, we tested a new R-ED setup, featuring an ML positioned on the hemodiafiltrate after the ED, at increasing ED current levels (0, 2, 4, 6, and 8 A). We measured VCO2ML, electrolytes concentrations, and pH of the extracorporeal circuit. Raising levels of ED-current increased chloride concentration from 107.5 ± 1.6 to 114.6 ± 1.3 mEq/L (0 vs. 8 A, p < 0.001) and reduced pH from 7.48 ± 0.01 to 6.51 ± 0.05 (0 vs. 8 A, p < 0.001) of the hemodiafiltrate entering the ML. Subsequently, VCO2ML increased from 27 ± 1.7 to 91.3 ± 1.5 ml/min (0 vs. 8 A, p < 0.001). Respiratory electrodialysis is efficient in increasing VCO2ML of an extracorporeal circuit featuring an ML perfused by hemodiafiltrate. During R-ED, the VCO2ML can be significantly enhanced by increasing the ED current.
authors.affiliation: From the *Dipartimento di Scienze della Salute, Università degli Studi di Milano Bicocca, Monza (MB), Italy; †Dipartimento di Anestesia e Rianimazione, Ospedale San Gerardo, Monza (MB), Italy; ‡Laboratorio Analisi Chimico Cliniche, Ospedale San Gerardo, Monza (MB), Italy; §Dipartimento di Anestesia, Rianimazione ed Emergenza Urgenza Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; and ¶Dipartimento di Fisiopatologia medico-chirurgica e dei trapianti Università degli Studi di Milano, Milan, Italy.
authors.forename: Alberto
authors.initials: A
authors.lastname: Zanella
authors.forename: Luigi
authors.initials: L
authors.lastname: Castagna
authors.forename: Salua
authors.initials: S
authors.lastname: Abd El Aziz El Sayed Deab
authors.forename: Vittorio
authors.initials: V
authors.lastname: Scaravilli
authors.forename: Daniela
authors.initials: D
authors.lastname: Ferlicca
authors.forename: Federico
authors.initials: F
authors.lastname: Magni
authors.forename: Marco
authors.initials: M
authors.lastname: Giani
authors.forename: Domenico
authors.initials: D
authors.lastname: Salerno
authors.forename: Marco
authors.initials: M
authors.lastname: Casati
authors.forename: Antonio
authors.initials: A
authors.lastname: Pesenti
mesh_terms: D002245:Carbon Dioxide / Q000097:blood*; D006801:Humans; D066298:In Vitro Techniques; D016060:Sorption Detoxification / Q000295:instrumentation / Q000379:methods*
chemical_list: D002245:Carbon Dioxide