Current correction factors inadequately predict the relationship between transcutaneous (tc) and arterial PCO2 in sick neonates.
Despite widespread tcPCO2 monitoring the relationship between tcPCO2 and PaCO2 remains unclear. It has been assumed that after standard temperature correction, a constant metabolic factor can explain the elevation of tcPCO2 over PaCO2. Our data demonstrate a progressive increase in the difference between temperature corrected tcPCO2 and PaCO2 as PaCO2 increases. Thus a constant metabolic factor cannot account for the elevation of temperature corrected tcPCO2 over PaCO2. We speculate that as PaCO2 rises, CO2 production exceeds removal resulting in a progressive gradient between temperature corrected tcPCO2 and PaCO2.
D001785:Blood Gas Monitoring, Transcutaneous / Q000379:methods*; D002245:Carbon Dioxide / Q000097:blood; D004566:Electrodes; D006801:Humans; D007231:Infant, Newborn; D012127:Respiratory Distress Syndrome, Newborn / Q000097:blood*
D002245:Carbon Dioxide