End-tidal CO2 monitoring in the pre-hospital environment: more than just endotracheal tube placement confirmation

Ambulance clinicians can encounter critically ill and injured patients in many unpredictable and challenging environments. The delivery of care and optimising use of all available equipment is essential. Effective measurement and interpretation of end-tidal carbon dioxide (ETCO₂) monitoring in relation to a patient's clinical state may be one of the most valuable and potentially underused tools available to pre-hospital clinicians (Donald and Paterson, 2006). Clinicians have a professional responsibility to maximise and fully understand all tools available to them to assist with their delivery of patient care (Health and Care Professions Council, 2014).

Measurement of carbon dioxide in expired ventilation gases has been used in anaesthesia practice since the late 1970s (Sinclair, 1998) and is mandatory practice in anaesthesia departments across the UK (Birks et al, 2007). This practice now extends from full anaesthesia, to situations where patients are given procedural sedation to facilitate a clinical procedure, as powerful sedative drugs can cause respiratory depression or periods of apnoea (Friedrich-Rust et al, 2013). Both of these clinical settings occur in well lit, dry and relatively controlled hospital environments. In contrast, within the pre-hospital environment there any many more associated challenges from environmental factors, available equipment, resources and clinical expertise. This environment and various challenges highlight the potential extra value from regular use of ETCO₂ monitoring in situations with critically ill patients. With this in consideration, there may be a need for further guidance and policy relating to ETCO₂ to support current ambulance clinicians and pre-hospital practice.