Funding for this research was provided by:
Received: 27 July 2020
Accepted: 16 October 2020
First Online: 30 October 2020
Ethics approval and consent to participate
: The study was approved by the ethics board of the Radboud University Medical Center (METC 2016-2366) and locally approved by participating centers (Amsterdam UMC, location VUmc: METC 2016.514; Canisius Wilhelmina Ziekenhuis: METC 128-2017). As patients were lacking the capacity to provide consent, written informed consent was provided by the substitute decision-maker prior to study procedures.
: Not applicable.
: AJM is employed by Liberate Medical, a medical device company that is developing an expiratory muscle stimulator. AHJ, TF, LMAH have received personal fees from Liberate Medical, outside of the submitted work. The other authors do not declare competing interests.