* [https://www.clinicalkey.com/#!/content/playContent/1-s2.0-S0749070409001274?returnurl=https:%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0749070409001274%3Fshowall%3Dtrue&referrer=https:%2F%2Fpubmed.ncbi.nlm.nih.gov%2F A paper] from 2010 showing continuous CO monitor applied to both ICU and OR environments using a Fick rebreathing technique. | * [https://www.clinicalkey.com/#!/content/playContent/1-s2.0-S0749070409001274?returnurl=https:%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS0749070409001274%3Fshowall%3Dtrue&referrer=https:%2F%2Fpubmed.ncbi.nlm.nih.gov%2F A paper] from 2010 showing continuous CO monitor applied to both ICU and OR environments using a Fick rebreathing technique. |