1. Department of Anesthesiology and Reanimation, Ankara Ataturk Training and Research Hospital, 06800 Ankara, Turkey
2. Department of Anesthesiology and Reanimation, Ulus State Hospital, 06050 Ankara, Turkey
3. Department of Anesthesiology and Reanimation, Ankara Numune Training and Research Hospital, 06230 Ankara, Turkey
4. Department of Anesthesiology and Reanimation, Faculty of Medicine, Yildirim Beyazit University, 06800 Ankara, Turkey
5. Department of Pulmonology, Ankara Yenimahalle State Hospital, 06370 Ankara, Turkey