title: The new advanced membrane gas exchanger.
abstract: Current membrane oxygenators are constructed for patients with a body surface under 2.2 m(2). If the body surface exceeds 2.5 m(2), commercially available devices may not allow adequate oxygenation during cardiopulmonary bypass. To address this, a hollow-fiber oxygenator with an enlarged contact surface of 1.81 m(2) was tested. In an experimental set-up, six calves of mean weight 85.4 ± 3 kg were connected to cardiopulmonary bypass. They were randomly assigned to a standard oxygenator (n = 3; ADMIRAL, Euroset, Medola, Italy) with a surface of 1.35 m(2) or to an enlarged surface oxygenator (n = 3; AMG, Euroset). Blood samples were taken before bypass, after 10 min on bypass, and after 1, 2, 5 and 6 h of perfusion. Analysis of variance was used for repeated measurements. The mean flow rate was 6.5 l/min for 6 h. The total oxygen transfer at 6 h was significantly higher in the high-surface group (P < 0.05). Blood trauma, evaluated by plasma hemoglobin and lactate dehydrogenase levels, did not detect any significant hemolysis. Thrombocytes and white blood cell count profiles showed no significant differences between the two groups at 6 h of perfusion (P = 0.06 and 0.80, respectively). At the end of testing, no clot deposition was found in the oxygenator, and there was no evidence of peripheral emboli. The results suggest that the new oxygenator allows very good gas transfer and may be used for patients with a large body surface area.
authors.affiliation: Department of Cardiovascular Surgery, Centre Hospitalier Universitaire Vaudois, Lausanne, Switzerland. denis.berdajs@chuv.ch
authors.forename: Denis A
authors.initials: DA
authors.lastname: Berdajs
authors.forename: Eleonora
authors.initials: E
authors.lastname: de Stefano
authors.forename: Dominique
authors.initials: D
authors.lastname: Delay
authors.forename: Enrico
authors.initials: E
authors.lastname: Ferrari
authors.forename: Judith
authors.initials: J
authors.lastname: Horisberger
authors.forename: Quntin
authors.initials: Q
authors.lastname: Ditmar
authors.forename: Ludwig K
authors.initials: LK
authors.lastname: von Segesser
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000097:blood; D001830:Body Surface Area; D002245:Carbon Dioxide / Q000097:blood; D002315:Cardiopulmonary Bypass / Q000009:adverse effects / Q000295:instrumentation*; D002417:Cattle; D020099:Coated Materials, Biocompatible; D004867:Equipment Design; D006454:Hemoglobins / Q000378:metabolism; D007770:L-Lactate Dehydrogenase / Q000097:blood; D007958:Leukocyte Count; D008422:Materials Testing; D023421:Models, Animal; D010100:Oxygen / Q000097:blood*; D010107:Oxygenators, Membrane; D010976:Platelet Count; D011126:Polypropylenes; D013997:Time Factors
chemical_list: D015415:Biomarkers; D020099:Coated Materials, Biocompatible; D006454:Hemoglobins; D011126:Polypropylenes; D002245:Carbon Dioxide; D007770:L-Lactate Dehydrogenase; D010100:Oxygen