Funding for this research was provided by:
Sundhed og Sygdom, Det Frie Forskningsråd (4183-00540)
Received: 16 April 2018
Accepted: 14 August 2018
First Online: 22 August 2018
: The extrasystoles method was previously protected by a patent application owned by Aarhus University (PCT/DK2014/050094; STV as sole inventor). The application did, however, not lead to the granting of a patent at priority expiry date.TWLS is an associate editor of the Journal of Clinical Monitoring and Computing. TWLS received honoraria for consulting from Edwards Lifesciences and Masimo Corp. TWLS is currently the Chair of the Section Cardiovascular Dynamics of the European Society of Intensive Care Medicine as well as the Chair of the Scientific Subcommittee 14 (Monitoring, Ultrasound, and Equipment) of the European Society of Anaesthesiology.Apart from this, all other authors declare that they have no competing interests.
: This study was exclusively observational and approved as such by the Danish authorities.
: Not applicable
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