%0 Journal Article %A Gregory A Schmidt %T Monitoring Gas Exchange %D 2020 %R 10.4187/respcare.07408 %J Respiratory Care %P 729-738 %V 65 %N 6 %X Critical illness can threaten the adequacy of O2 delivery or CO2 excretion. Monitoring seeks to identify the adequacy of oxygenation and ventilation and to detect deterioration early. Advances in oximetry, capnography, and transcutaneous CO2 monitoring offer new opportunities for more accurate estimation of gas exchange, noninvasive monitoring of parameters previously not amenable (eg, total hemoglobin measurement), detection of disease, and prediction of fluid responsiveness. %U https://rc.rcjournal.com/content/respcare/65/6/729.full.pdf