Received: 4 September 2020
Accepted: 2 November 2020
First Online: 20 November 2020
Ethics approval and consent to participate
: All patients signed an informed consent and the study was performed in accordance with the declaration of Helsinki. The study design was approved by the Ethical Committee of Erasmus University Hospital, Brussels (ref P2017/348 on 21/06/2017).
: Not applicable.
: The authors have no disclosure for this research.Grünenthal GmbH provided our hospital with non-financial support. Specifically, this company offered a free rental of the zalviso administration device (sufentanil cartridge not included) without any compensation.