Pediatric Critical Care Fellow University of California San Francisco University of California San Francisco San Francisco, California, United States
Background: In 1953, Abraham Rudolph described patients with cyanotic congenital heart disease (CCHD) at risk for “relative anemia” with polycythemia (elevated red blood cell count, RBCC), low normal hematocrit (Hct), and low mean corpuscular volume (MCV), responsive to iron supplementation (30 mg/d). The American Academy of Pediatrics (AAP) recommends 1 mg/kg/d of supplemental iron for breastfed infants and an iron intake of 4-12 mg/d for formula fed, but there are no guidelines specific to children with CCHD.
Objective: To investigate the iron status in infants and children with CCHD in relation to age and iron supplementation.
Design/Methods: Patients 2 months to 6 years undergoing cardiac catheterization or cardiac surgery for CCHD with saturations <90% and on enteral feeds were prospectively enrolled (Oct 2019 – Dec 2020). Patients were excluded if they had a blood transfusion or known infection within 8 weeks, genetic or extracardiac anomaly known to be associated with anemia, hemoglobinopathies. Complete blood cell count, ferritin, serum iron, transferrin and transferrin saturation were examined. Chart was reviewed for demographics, anthropometrics, cardiac/surgical history, nutrition, past blood counts and transfusions, and hemodynamics.
Results: Nineteen subjects consisting of 1 Tetralogy of Fallot, 10 Glenns, 4 Norwoods, and 4 pulmonary artery band were included. None of the patients were anemic based on Hct, hemoglobin (Hgb), MCV, and RBCC was elevated (median 85, range 75-93) . All subjects had iron studies including ferritin, serum iron, transferrin, and transferrin saturation within the normal range. 9/19 (47%) subjects were on supplemental iron with a median supplemental iron intake of 9 (IQR 6.8, 10.5) mg/day or 1.7 (IQR 0.9, 2.7) mg/kg/day. Patients on supplementation were younger [5 (IQR 4, 10) vs 36.5 (IQR 18.3, 44.8) months, p = 0.02] and had higher ferritin (p=0.02) and MCV (Table). There was no difference in oxygen saturation, Hgb, Hct, serum iron, or transferrin between patients on and not on iron supplementation though the age difference between groups and potential for dietary iron variation in older children may be obscuring a difference. Conclusion(s): Routine AAP guideline iron supplementation is associated with adequate iron stores with increased ferritin and transferrin saturation and no relative anemia in infants with CCHD vs. largely unsupplemented older children. Whether CCHD patients would benefit from continued supplementation in childhood remains to be studied.
Authors/Institutions: Anyir Hsieh, University of California San Francisco, San Francisco, California, United States; Christiana Tai, University of California San Francisco, San Francisco, California, United States; Jessica Thai, University of California San Francisco, San Francisco, California, United States; Holly Stevens, University of California San Francisco, San Francisco, California, United States; Anita J. Moon-Grady, University of California San Francisco School of Medicine, Mill Valley, California, United States