Peter E Spronk1,2,4
, Jos NM Barendregt3
, Guus Crooijmans3
, Yolande M Vermeeren3
and Johannes H Rommes1 
1
Department of Intensive Care Medicine, Gelre Hospitals, Apeldoorn, The Netherlands
2
Department of Intensive Care Medicine, Academic Medical Center, Amsterdam, The Netherlands
3
Department of Internal Medicine, Gelre Hospitals, Apeldoorn, The Netherlands
4
Hermes critical care group, Amsterdam, The Netherlands