title: A novel pump-driven veno-venous gas exchange system during extracorporeal CO2-removal.
abstract: OBJECTIVE
  Pump-driven veno-venous extracorporeal CO2-removal (ECCO2-R) increasingly takes root in hypercapnic lung failure to minimize ventilation invasiveness or to avoid intubation. A recently developed device (iLA activve(®), Novalung, Germany) allows effective decarboxylation via a 22 French double lumen cannula. To assess determinants of gas exchange, we prospectively evaluated the performance of ECCO2-R in ten patients receiving iLA activve(®) due to hypercapnic respiratory failure.
  
  
  METHODS
  Sweep gas flow was increased in steps from 1 to 14 L/min at constant blood flow (phase 1). Similarly, blood flow was gradually increased at constant sweep gas flow (phase 2). At each step gas transfer via the membrane as well as arterial blood gas samples were analyzed.
  
  
  RESULTS
  During phase 1, we observed a significant increase in CO2 transfer together with a decrease in PaCO2 levels from a median of 66 mmHg (range 46-85) to 49 (31-65) mmHg from 1 to 14 L/min sweep gas flow (p < 0.0001), while arterial oxygenation deteriorated with high sweep gas flow rates. During phase 2, oxygen transfer significantly increased leading to an increase in PaO2 from 67 (49-87) at 0.5 L/min to 117 (66-305) mmHg at 2.0 L/min (p < 0.0001). Higher blood flows also significantly enhanced decarboxylation (p < 0.0001).
  
  
  CONCLUSIONS
  Increasing sweep gas flow results in effective CO2-removal, which can be further reinforced by raising blood flow. The clinically relevant oxygenation effect in this setting could broaden the range of indications of the system and help to set up an individually tailored configuration.
authors.affiliation: Department of Medicine I, Intensive Care Unit 13i2, General Hospital Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Alexander
authors.initials: A
authors.lastname: Hermann
authors.affiliation: Department of Medicine I, Intensive Care Unit 13i2, General Hospital Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Katharina
authors.initials: K
authors.lastname: Riss
authors.affiliation: Department of Medicine I, Intensive Care Unit 13i2, General Hospital Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Peter
authors.initials: P
authors.lastname: Schellongowski
authors.affiliation: Department of Medicine I, Intensive Care Unit 13i2, General Hospital Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Andja
authors.initials: A
authors.lastname: Bojic
authors.affiliation: Department of Medicine I, Intensive Care Unit 13i2, General Hospital Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Philipp
authors.initials: P
authors.lastname: Wohlfarth
authors.affiliation: Department of Medicine I, Intensive Care Unit 13i2, General Hospital Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Oliver
authors.initials: O
authors.lastname: Robak
authors.affiliation: Department of Medicine I, Intensive Care Unit 13i2, General Hospital Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria.
authors.forename: Wolfgang R
authors.initials: WR
authors.lastname: Sperr
authors.affiliation: Department of Medicine I, Intensive Care Unit 13i2, General Hospital Vienna, Medical University of Vienna, Waehringer Guertel 18-20, 1090, Vienna, Austria. thomas.staudinger@meduniwien.ac.at.
authors.forename: Thomas
authors.initials: T
authors.lastname: Staudinger
mesh_terms: D000328:Adult; D000368:Aged; D001317:Austria; D001784:Blood Gas Analysis / Q000295:instrumentation*; D002245:Carbon Dioxide / Q000097:blood*; D003653:Decarboxylation; D004867:Equipment Design; D015199:Extracorporeal Membrane Oxygenation / Q000009:adverse effects* / Q000295:instrumentation*; D005260:Female; D005858:Germany; D006801:Humans; D006935:Hypercapnia / Q000097:blood* / Q000209:etiology* / Q000628:therapy; D008171:Lung Diseases / Q000628:therapy*; D008297:Male; D008875:Middle Aged
chemical_list: D002245:Carbon Dioxide
keywords: Decarboxylation; ECCO2-R; Extracorporeal circulation; Hypercapnia; iLA activve®