2025 – PAGE 280 – HEMATOLOGY & ONCOLOGY

NEWBORN ANEMIA 

Anemia in a newborn is defined as a hemoglobin of less than 13 (KNOW THIS)! The table below provides you with some average hemoglobin values at different ages.

RBC MCV

• NEWBORNS may have an RBC MCV up to 110. That is considered NORMAL.
• 6 MONTHS – 2 YEARS: At this age, the normal range is 70-90. Note that this is a LOWER range than older children and adults (80-100).

POLYCYTHEMIA

Neonatal polycythemia is defined by a hematocrit greater than 65%, but treatment is not required unless the HCT is greater than 70% by a VENOUS blood sample. Patients are at risk for problems associated with hyperviscosity. Potential signs and symptoms include hypoglycemia, thrombocytopenia, joint pain, clots (deep vein thrombosis or pulmonary embolus), stroke, hemoptysis, lethargy, and hypotonia. Risk factors include intrauterine growth retardation (IUGR), delayed clamping of the umbilical cord, twin-to-twin transfusion, infant of a diabetic mother (IDM), Down Syndrome, and chronic hypoxia (which refers more to an older child). Treat with partial volume exchange transfusion. Note that polycythemia in older children is rare.

PEARLS: If the patient is hypoglycemic due to polycythemia, the blood glucose may not correct as expected with the usual dextrose infusion.

MNEMONIC: Assume the RBCs are sucking up all the glucose!

PRBC TRANSFUSIONS

A standard packed red blood cell (PRBC) transfusion is 10-20 cc/kg.

PEARLS: Massive PRBC transfusions and exchange transfusions both have similar complications: Hypocalcemia, hyperkalemia, and thrombocytopenia.

MNEMONICS: Regarding the 10-20 cc/kg, think of it as giving a “bolus” of PRBCs. A bolus of IVF is 20 cc/kg. Regarding complications, think of calcium precipitating out as the two different bloods mix (actually it’s a citrate toxicity). For the hyperkalemia, imagine RBCs hemolyzing as they get sheared through the IV. For thrombocytopenia, assume it’s a hemodilutional effect!

NORMOCYTIC ANEMIA

PHYSIOLOGIC ANEMIA

The phrase “physiologic anemia” refers to a normal process. Fetal hemoglobin has a high affinity for oxygen. It slowly gets replaced by adult hemoglobin (A1), which has a lower affinity for oxygen. Since A1 doesn’t hold on to oxygen very well, it allows the release of O2 into the tissues. As more A1 is made and more O2 is released, there is a decreased need for erythropoietin. This results in decreased RBC production and a “physiologic anemia.” The Hgb nadir (low point) occurs sometime between 6 and 16 weeks. It should not be lower than a hemoglobin of 9 for term infants and 7 for premature infants. That is about the level at which erythropoietin production increases again, resulting in a rise in A1 hemoglobin production. There is no iron deficiency or structural problem. Everything is normal, so it will be a NORMOCYTIC anemia.