Received: 15 October 2019
Accepted: 23 December 2019
First Online: 13 January 2020
Ethics approval and consent to participate
: In unresponsive patients, informed consent was first obtained from the legal representatives. Consent for the use of the study data was asked at a later time if the patient recovered consciousness. If the patient died before consent was obtained, the study data was used, and the legal representatives were informed of the study. The study was approved by the local institutional review board (METc M15.168207).
: Not applicable
: The authors declare that they have no competing interests.