Fetal Hemoglobin

Abstract

Abstract Fetal hemoglobin (HbF) is a physiologic variant of the adult hemoglobin (HbA) protein. It is primarily present in the fetus. HbA has a lower oxygen affinity than HbF. A newborn’s hemoglobin transitions from HbF to HbA with 70% HbF at 40 weeks’ gestational age to almost 0% at 6 months after birth. Transfusion with HbA blood or premature birth can affect the rate and timing of this transition. The change in proportion of HbF will affect the degree of oxygen saturation of hemoglobin for a given partial pressure of oxygen due to the difference in the oxygen-hemoglobin dissociation curve. A thorough history and careful evaluation of monitoring devices allow the anesthesiologist to optimize oxygen delivery perioperatively.