1. Department of Anesthesiology, Intensive Care Medicine and Pain Therapy, University Hospital Frankfurt, Goethe University, Frankfurt, Germany
2. Main-Kinzig-Clinic, Department of Anesthesia, Intensive Care Medicine and Pain Therapy, Herzbachweg 14, 63571 Gelnhausen, Germany
3. Evangelical Hospital Oldenburg, Department of Anesthesia, Intensive Care Medicine and Pain Therapy, Steinweg 13-17, 26122 Oldenburg, Germany
4. Asklepios Clinics Hamburg, Asklepios Clinic Wandsbek, Department of Anesthesiology, Intensive Care Medicine and Emergency Medicine, Alphonsstraße 14, 22043 Hamburg, Germany