A prospective, observational study investigating the level of agreement between transcutaneous and invasive carbon dioxide measurements in critically ill emergency department patients

This study is comparing measurements of carbon dioxide levels in arterial blood (standard care for critically unwell patients) with measurements of carbon dioxide taken from a transcutaneous (skin surface) probe. Our study will look at the level of agreement between these two measurement methods to examine whether the skin probe is adequate to monitor carbon dioxide in the emergency department setting. If shown to be adequate, it could spare patients a painful procedure (arterial cannulation) which is currently required as the standard of care. Our intervention is the use of the Sentec Digital Monitor System to perform carbon dioxide level measurements at 4 time intervals for the study participants. Emergency department nursing staff will use the Sentec Digital Monitor System's sensor which is clipped to the patient's ear to perform transcutaneous measurement of carbon dioxide levels at 0mins, 30mins, 60mins and 90mins post enrolment in the emergency department resuscitation area.