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Efficacy and safety of lower versus higher CO2 extraction devices to allow ultraprotective ventilation: secondary analysis of the SUPERNOVA study
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  • Published on:
    Response to Laura W Lund, and Jeremy D Kimmel ALung Technologies January 16, 2020
    • Vito Marco Ranieri, Anesthesia and Intensive Care Medicine Alma Mater Studiorum University of Bologna Policlinico di Sant'Orsola
    • Other Contributors:

    The SUPERNOVA trial was a prospective observational phase II study supported by an unrestricted grant from three companies (Alung, Maquet, and Novalung) and by the European Society of Intensive Care Medicine (ESICM). The three companies provided equipment and covered costs for data monitoring, site visits, and insurance fees. The grant (€171,000) was made available to ESICM that supported data collection and analysis, and all administrative costs. As owner of the data, ESICM appointed the two principal investigators (AC and VMR) and the independent Data and Safety Monitoring Board (Jukka Takala, Chair). The study included 95 patients. The proportion of patients who achieved ultra-protective settings by 24 hours was 82%. Number of patients that experienced severe and ECCO2R-related adverse events was 2 (2%) and 37 (39%)1. Retrospective analysis of these data showed that (a) efficacy of ECCO2R to facilitate further reduction of tidal volume was lower with smaller artificial lungs and running at lower blood flow than with larger artificial lungs and running at a higher blood flow2; (b) haemolysis and bleeding was higher with the former than with the latter2; (c) applying these data to a previously described theoretical model3 we predicted that incorporating higher CO2 removal rates as factors to design randomized clinical trial might substantially reduce screening and sample size requirements4.
    In her letter, Dr Lund, expressed several concerns about these findin...

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    Conflict of Interest:
    None declared.
  • Published on:
    Response to "Efficacy and safety of lower versus higher CO2 extraction devices to allow ultraprotective ventilation: secondary analysis of the SUPERNOVA study" (Combes et al,, 2019 Dec;74(12))
    • Laura W Lund, Vice President of Clinical Science ALung Technologies
    • Other Contributors:
      • Jeremy D Kimmel, Vice President of New Technology

    Dear Editor,

    We read with great interest the recently published article in Thorax by Combes and colleagues titled “Efficacy and safety of lower versus higher CO2 extraction devices to allow ultraprotective ventilation: secondary analysis of the SUPERNOVA study” [1]. In this article, the authors present brief, post-hoc analyses of safety and efficacy data derived from the SUPERNOVA trial, a single-arm, multi-center, pilot study assessing the feasibility and safety of extracorporeal carbon dioxide removal (ECCO2R) to facilitate ultra-protective ventilation in patients with moderate acute respiratory distress syndrome (ARDS) [2]. The study was conducted at 23 centers, each of which used one of three different ECCO2R devices.

    We wish to communicate significant concerns regarding improper categorization of ECCO2R device performance as well as important study limitations impacting interpretation and value of the presented data. The differentiation between devices based on the terms “higher CO2 extraction” and “lower CO2 extraction” is incorrect based on supporting evidence and engineering principles summarized in this letter. In addition, safety data was presented and statistically compared without including available associated data that would bring in to question the implications of the analyses. As the manufacturer of one of the ECCO2R devices used in the SUPERNOVA pilot study, we are strong believers in the life-saving potential of ECCO2R technology and its...

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    Conflict of Interest:
    Both authors are employed by ALung Technologies, the manufacturer of one of the medical devices used in the Supernova study, specifically, the Hemolung Respiratory Assist System.