title: Efficiency of gas transfer in venovenous extracorporeal membrane oxygenation: analysis of 317 cases with four different ECMO systems.
abstract: OBJECTIVE
  Polymethylpentene membrane oxygenators used in venovenous extracorporeal membrane oxygenation (vvECMO) differ in their physical characteristics. The aim of the study was to analyze the gas transfer capability of different ECMO systems in clinical practice, as the choice of the appropriate system may be influenced by the needs of the patient.
  
  
  METHODS
  Retrospective study on prospectively collected data of adults with severe respiratory failure requiring vvECMO support (Regensburg ECMO Registry, 2009-2013). Oxygen (O2) transfer and carbon dioxide (CO2) elimination of four different ECMO systems (PLS system, n = 163; Cardiohelp system (CH), n = 59, Maquet Cardiopulmonary, Rastatt, Germany; Hilite 7000 LT system, n = 56, Medos Medizintechnik, Stolberg, Germany; ECC.05 system, n = 39, Sorin Group, Mirandola (MO), Italy) were analyzed.
  
  
  RESULTS
  Gas transfer depended on type of ECMO system, blood flow, and gas flow (p ≤ 0.05, each). CO2 removal is dependent on sweep gas flow and blood flow, with higher blood flow and/or gas flow eliminating more CO2 (p ≤ 0.001). CO2 elimination capacity was highest with the PLS system (p ≤ 0.001). O2 transfer at blood flow rates below 3 l/min depended on blood flow, at higher blood flow rates on blood flow and gas flow. The system with the smallest gas exchange surface (ECC.05 system) was least effective in O2 transfer, but in terms of the gas exchange surface was the most effective.
  
  
  CONCLUSIONS
  Our analysis suggests that patients with severe hypoxemia and need for high flow ECMO benefit more from the PLS/CH or Hilite 7000 LT system. The ECC.05 system is advisable for patients with moderate hypoxemia and/or hypercapnia.
authors.affiliation: Department of Cardiothoracic Surgery, University Medical Center Regensburg, 93042, Regensburg, Germany.
authors.forename: Karla
authors.initials: K
authors.lastname: Lehle
authors.forename: Alois
authors.initials: A
authors.lastname: Philipp
authors.forename: Karl-Anton
authors.initials: KA
authors.lastname: Hiller
authors.forename: Florian
authors.initials: F
authors.lastname: Zeman
authors.forename: Dirk
authors.initials: D
authors.lastname: Buchwald
authors.forename: Christof
authors.initials: C
authors.lastname: Schmid
authors.forename: Christian
authors.initials: C
authors.lastname: Dornia
authors.forename: Dirk
authors.initials: D
authors.lastname: Lunz
authors.forename: Thomas
authors.initials: T
authors.lastname: Müller
authors.forename: Matthias
authors.initials: M
authors.lastname: Lubnow
mesh_terms: D000328:Adult; D000368:Aged; D002245:Carbon Dioxide / Q000378:metabolism*; D004867:Equipment Design; D015199:Extracorporeal Membrane Oxygenation / Q000295:instrumentation* / Q000706:statistics & numerical data*; D005260:Female; D005858:Germany; D006439:Hemodynamics / Q000502:physiology; D006801:Humans; D006935:Hypercapnia / Q000209:etiology / Q000517:prevention & control*; D000860:Hypoxia / Q000209:etiology / Q000517:prevention & control*; D007558:Italy; D008297:Male; D008875:Middle Aged; D010100:Oxygen / Q000378:metabolism*; D012131:Respiratory Insufficiency / Q000150:complications / Q000628:therapy*; D012189:Retrospective Studies
chemical_list: D002245:Carbon Dioxide; D010100:Oxygen