Elective red cell transfusions for anemia of prematurity and development of necrotizing enterocolitis in previously well preterm neonates: Incidence and difficulties in proving a cause-effect relation

Abstract

Objectives: Study the incidence of the unexpected development of necrotizing enterocolitis (NEC) following an elective packed red blood cell (PRBC) transfusion for anemia of prematurity (AOP) in previously stable, growing preterm neonates.

Methods: Retrospective analysis (Jan 2001–July 2006) of data on all admissions to our tertiary neonatal unit who received a PBRC transfusion and/or had definite (Stage ⩾ II) NEC.

Results: 7935 neonates were admitted over the study period including 4833 (61%) with gestation <37 weeks (preterm). 793 preterm neonates received 2191 elective PRBC transfusions (median 2, range 1–12) for AOP. Definite NEC occurred in 37 (0.8%) preterm neonates with 7 developing it within 48 hours of a PRBC transfusion. Only 1/7 was a stable, and growing (without oxygen/respiratory assistance, full feeds, otherwise well except for symptomatic AOP) neonate.

Conclusion: Unexpected development of NEC following an elective PRBC transfusion in a previously well and stable neonate was rare in our population of high-risk neonates. Given the low incidence of NEC, and the range of possible risk factors (e.g. free radicals, mesenteric ischemia, hypovolemia, proinflammatory cytokines in the transfused product, prematurity, IGUR), designing and conducting large prospective observational studies is very difficult to prove a causal relation between PRBC transfusions and NEC.