Transcutaneous carbon dioxide monitoring: ready to be standard of care?

Tight control of respiratory gases is a tenant of good critical care, particularly in very low birth weight (VLBW) infants. In these infants, high and low oxygen (O 2 ) and carbon dioxide (CO 2 ) levels are associated with increased mortality and lung injury as well as preterm specific risks such as intraventricular haemorrhage (IVH), chronic lung disease and retinopathy of prematurity (ROP). 1 , 2 Achieving tight O 2 and CO 2 control requires knowing what values to target and having a method to monitor levels. Blood gas analysis remains the gold standard method of assessing O 2 and CO 2 but does not allow the frequency needed to address the dynamic nature of critical care, leave clinicians effectively blind to rapid fluctuations. Continuous monitoring of O 2 with peripheral oxygen saturation (SpO 2 ) has been standard of care in NICU for more than 20 years. Achieving the same with CO 2 has been less widely adopted despite the availability of end-tidal and transcutaneous CO 2 (TcCO 2 ) systems. 3