1 Department of Anesthesiology, University of Oklahoma Health Sciences Center, 920 Stanton L. Young Blvd., WP1140, Oklahoma City, OK, 73104, USA.
2 College of Medicine, University of Oklahoma Health Sciences Center, Oklahoma City, USA.
3 Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, USA.
4 Department of Anesthesiology, University of Oklahoma Health Sciences Center, 920 Stanton L. Young Blvd., WP1140, Oklahoma City, OK, 73104, USA. [email protected].