CPT® Code 85460

The CPT® Code 85460 refers to a laboratory test specifically designed to measure the percentage of fetal hemoglobin or red blood cells (RBCs) present in maternal blood, particularly in the context of fetomaternal hemorrhage (FMH). This test employs a differential lysis technique known as the Kleihauer-Betke test, which is crucial for distinguishing fetal hemoglobin from maternal hemoglobin. The process involves an acid elution method that effectively eliminates maternal hemoglobin, allowing fetal hemoglobin to remain intact and susceptible to staining. This is significant because during pregnancy and delivery, fetal blood can mix with maternal blood, leading to potential complications, especially in cases where an Rh-negative mother is carrying an Rh-positive fetus. Such mixing can result in maternal Rh immunization, which poses risks for future pregnancies. By quantifying the extent of FMH, healthcare providers can make informed decisions regarding the administration of Rh immune globulin (RhoGAM) to the mother, particularly postpartum or after a preterm fetal loss. The test is performed on a blood sample obtained through a separately reportable venipuncture, and the analysis is conducted on whole blood using a semi-quantitative acid elution eosin stain and microscopy to accurately assess the fetal hemoglobin levels.