Manuel Á Gómez-Ríos1,2, Cesar Bonome3. 1. Department of Anesthesiology and Perioperative Medicine, University Hospital of A Coruña, A Coruña, Spain - magoris@hotmail.com. 2. Anesthesiology and Pain Management Research Group, Institute for Biomedical Research of A Coruña (INIBIC), A Coruña, Spain - magoris@hotmail.com. 3. Department of Anesthesiology and Perioperative Medicine, University Hospital of A Coruña, A Coruña, Spain.