1. Faculty of Medicine, Riga Stradins University, 1007 Riga, Latvia
2. Anesthesiology, Intensive Care and Pain Department, Riga 1st Hospital, 1001 Riga, Latvia
3. Department of Anesthesiology and Intensive Care, Riga Stradins University, 1007 Riga, Latvia
4. Clinic of Anesthesiology and Reanimatology, Paul Stradins Clinical University Hospital, 1002 Riga, Latvia