End-Tidal Breath Carbon Monoxide Measurements: Current Directions

Abstract

Because heme catabolism leads to the formation of equimolar amounts of carbon monoxide (CO) and bilirubin, a variety of techniques have been developed to correlate CO production rates as indices of bilirubin production. The use of end-tidal breath CO measurements for estimating rates of bilirubin production in infants has been well documented and validated in a number of clinical studies for its use and predictive value in identifying infants who are high producers of bilirubin and hence at risk for developing pathologic neonatal hyperbilirubinemia. Recently, end-tidal breath CO has been suggested as a marker for chronic lung disease and developmental problems. Trace gas analysis remains an area for interesting investigation in the future.