title: Modular extracorporeal life support: effects of ultrafiltrate recirculation on the performance of an extracorporeal carbon dioxide removal device.
abstract: The combination of extracorporeal carbon dioxide removal (ECCO2R) and hemofiltration is a possible therapeutic strategy for patients needing both lung and renal support. We tested the effects of the recirculation of ultrafiltrate on membrane lung (ML) CO2 removal (VCO2ML). Three conscious, spontaneously breathing sheep were connected to a commercially produced ECCO2R device (Hemolung; Alung Technologies, Pittsburgh, PA) with a blood flow of 250 ml/min and a gas flow of 10 L/min. A hemofilter (NxStage, NxStage Medical, Lawrence, MA) was interposed in series after the ML. Ultrafiltrate flow was generated and recirculated before the ML. We tested four ultrafiltrate flows (0, 50, 100, and 150 ml/min) for 25 min each, eight times per animal, resulting in 24 randomized test repetitions. We recorded VCO2ML, hemodynamics and ventilatory variables, and natural lung CO2 transfer (VCO2NL) and collected arterial and circuitry blood samples. VCO2ML was unchanged by application of ultrafiltrate recirculation (40.5 ± 4.0, 39.7 ± 4.2, 39.8 ± 4.2, and 39.2 ± 4.1 ml/min, respectively, at ultrafiltrate flow of 0, 50, 100, and 150 ml/min). Minute ventilation, respiratory rate, VCO2NL, and arterial blood analyses were not affected by ultrafiltrate recirculation. In the tested configuration, ultrafiltrate recirculation did not affect VCO2ML. This modular technology may provide a suitable platform for coupling CO2 removal with various forms of blood purification.
authors.affiliation: From the *Comprehensive Intensive Care Research Task Area, Battlefield Health and Trauma Research Institute, U.S. Army Institute of Surgical Research, Fort Sam Houston, San Antonio, Texas; †Department of Experimental Medicine, University Milano-Bicocca, Monza (MB), Italy; ‡Department of Anesthesiology and Intensive Care Medicine, University Hospital Bonn, Bonn, Germany; §Pediatric Department, University Hospital Bonn, Bonn, Germany; ¶Department of Perioperative Medicine and Intensive Care, San Gerardo Hospital, Monza (MB), Italy; and ‖Department of Trauma & Critical Care, San Antonio Military Medical Center, San Antonio, Texas.
authors.forename: Vittorio
authors.initials: V
authors.lastname: Scaravilli
authors.forename: Stefan
authors.initials: S
authors.lastname: Kreyer
authors.forename: Katharina
authors.initials: K
authors.lastname: Linden
authors.forename: Slava
authors.initials: S
authors.lastname: Belenkiy
authors.forename: Bryan
authors.initials: B
authors.lastname: Jordan
authors.forename: Antonio
authors.initials: A
authors.lastname: Pesenti
authors.forename: Alberto
authors.initials: A
authors.lastname: Zanella
authors.forename: Kevin
authors.initials: K
authors.lastname: Chung
authors.forename: Jeremy
authors.initials: J
authors.lastname: Cannon
authors.forename: Leopoldo C
authors.initials: LC
authors.lastname: Cancio
authors.forename: Andriy I
authors.initials: AI
authors.lastname: Batchinsky
mesh_terms: D000818:Animals; D001784:Blood Gas Analysis; D002245:Carbon Dioxide / Q000737:chemistry*; D004867:Equipment Design; D005112:Extracorporeal Circulation / Q000379:methods*; D015199:Extracorporeal Membrane Oxygenation / Q000379:methods*; D005260:Female; D005440:Fluid Therapy / Q000379:methods; D006339:Heart Rate; D006439:Hemodynamics; D006440:Hemofiltration / Q000295:instrumentation; D012121:Respiration, Artificial / Q000295:instrumentation; D012131:Respiratory Insufficiency / Q000628:therapy; D012756:Sheep; D013997:Time Factors
chemical_list: D002245:Carbon Dioxide