1. Department of Anaesthesiology, Intensive Care, Emergency and Pain Medicine, University Medicine of Greifswald, Greifswald, Germany
2. Department of Internal Medicine, University Medicine of Greifswald, Greifswald, Germany
3. Institute of Medical Psychology, University Medicine of Greifswald, Greifswald, Germany
4. Department of Anesthesia, McMaster University, Hamilton, Ontario, Canada