Perinatal Hemolytic Disorders and Identification Using End Tidal Breath Carbon Monoxide

Hemolytic disorders can cause severe morbidity or can be life-threatening. Before the recent development of practical and inexpensive testing for hemolysis by quantifying carbon monoxide in end-tidal breath, some hemolytic disorders in perinatal patients were not detected until severely problematic hyperbilirubinemia and/or anemia occurred. Here we review studies aimed at establishing the normal reference intervals for end tidal breath carbon monoxide (ETCO) in various perinatal populations. We also review reports, and new theories, about using this methodology to diagnose and quantify hemolytic disorders in term and premature neonates, anemic pregnant women, and fetuses in utero. The purposes of making these measurements are to; (1) identify patients who have hemolytic disorders, (2) characterize the severity of the hemolysis in each hemolytic patient, and (3) predict and prevent co-morbidities, thereby improving outcomes.