ANEMIA OF PREMATURITY
Anemia of prematurity, anemia in preterm infants, or neonatal anemia is defined as a low hemoglobin or hematocrit concentration of more than two standard deviations below the mean for postnatal age. It is a major problem encountered in neonatal intensive care units (NICUs; Colombatti, Sainati, & Trevisanuto, 2016). Blood transfusions and administration of iron and erythropoiesis-stimulating agent are common nursing care measures in NICUs to address this clinical issue. There is also a role for the nurse in the promotion of delayed cord clamping for the prevention of anemia in this cohort of patients (Colombatti et al., 2016).
Anemia of prematurity is an exaggerated drop in the hemoglobin (Hb)/hematocrit (Hct), more than that expected physiologically in these infants. Preterm infants are those at less than 37 weeks gestation (American Academy of Pediatrics and the American College of Obstetricians and Gynecologists, 2012). All infants experience a drop in their Hb/Hct levels after birth in the first few weeks of life. This is called physiologic anemia of the newborn and it may go unnoticed. In preterm infants, the anemia is more pronounced and the drop is faster, often presenting with symptoms, including pallor, tachypnea, poor feeding, poor growth, lethargy, and tachycardia, and frequently requiring treatment (Gardner, Carter, Hines, & Hernández, 2016). Anemia of prematurity is present in all preterm infants, but may not cause symptoms. Infants equal to or less than 32 weeks gestation often require blood transfusions; one citation estimates 80% of infants less than 32 weeks gestation require transfusion (Colombatti et al., 2016).
Anemia of prematurity presents with normocytic, normochromic, hyporegenerative anemia and this can be determined when evaluating the results of the complete blood count (CBC). The reticulocyte count is the index that reveals the bone marrow’s response to anemia; a higher count would indicate that more new red blood cells are being manufactured.
Preterm infants, particularly those at 32 weeks and less, frequently require a myriad of medical interventions to assist them in breathing, digesting nutrients, and maintaining homeostasis. These medical interventions require frequent blood sampling to assess their adequacy. The preterm infant is ill equipped to respond to this demand for blood sampling. Preterm infants frequently are iron deficient, nutritionally deficient, and suffer from other chronic illnesses that contribute to their anemia.
Erythropoiesis or the making of new red blood cells in a newborn infant is a complex phenomenon and quite different from that of an adult. During human 122gestation, blood formation occurs initially in the yolk sac; during the second trimester, this changes to the liver, spleen, and lymph nodes. Finally, in the last half of gestation, the bone marrow takes over (Colombatti et al., 2016