Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Daniel Bolliger reports writing assistance was provided by University Hospital Basel. Daniel Bolliger reports a relationship with University Hospital Basel that includes: employment. Nuno Gomes reports a relationship with University Hospital Basel that includes: employment. No other relationship or activity to declare. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.