title: CO2 removal for ventilatory support: a comparison of dialysis with and without carbonic anhydrase to a hollow fiber lung.
abstract: All CO2 in blood is in equilibrium, catalyzed by carbonic anhydrase (CA). This has prompted some investigators to consider treating ventilatory failure by using dialysis to remove HCO3-. Since there is at least 18 times more CO2 in the form of HCO3- than dissolved CO2, theoretically, lower blood flows could be used than with current extracorporeal support with artificial membrane lungs. HCO3- removal for ventilatory support has required alkalinization to compensate for the resulting acidosis and has been capable of removing 26 to 38 ml CO2/100 ml blood flow, compared to 14 ml CO2/100 ml for clinically employed silicone membrane lungs. We designed a HCO3- removal system using recirculation of dialysate through a membrane lung to remove CO2, rather than alkalinization of blood, and removed 8.8 ml CO2/100 ml. Adding CA improved this to 12.2 ml CO2/100 ml, but a conventional hollow fiber lung removed 30 ml CO2/100 ml. We conclude that the complexities of an HCO3- removal system may not be necessary with the advent of more efficient hollow fiber lungs.
authors.affiliation: Department of Surgery, Wayne State University, Detroit, Michigan.
authors.forename: P
authors.initials: P
authors.lastname: Mancini
authors.forename: G C
authors.initials: GC
authors.lastname: Whittlesey
authors.forename: J Y
authors.initials: JY
authors.lastname: Song
authors.forename: S O
authors.initials: SO
authors.lastname: Salley
authors.forename: M D
authors.initials: MD
authors.lastname: Klein
mesh_terms: D001639:Bicarbonates / Q000097:blood*; D002245:Carbon Dioxide / Q000097:blood*; D002256:Carbonic Anhydrases / Q000097:blood*; D003956:Dialysis / Q000295:instrumentation*; D004867:Equipment Design; D015199:Extracorporeal Membrane Oxygenation / Q000295:instrumentation*; D006801:Humans; D006863:Hydrogen-Ion Concentration; D008955:Models, Cardiovascular; D010100:Oxygen / Q000097:blood; D010107:Oxygenators, Membrane
chemical_list: D001639:Bicarbonates; D002245:Carbon Dioxide; D002256:Carbonic Anhydrases; D010100:Oxygen