The Effect of Amaemia and Red Blood Cell Transfusion on Gut Tissue Injury in Preterm Infants

Background Necrotising enterocolitis (NEC) is an intestinal inflammatory disease with significant morbidity and mortality. The pathophysiology is multifactorial and both red blood cell transfusion (RBCT) and, more recently, severe anaemia has been linked with NEC. Primary Objectives 1. Investigate the association between Haemoglobin and RBCT with intestinal tissue injury. 2. Establish whether changes in gut tissue biomarkers could predict NEC onset. 3. Establish whether cerebral and splanchnic oxygenation differ in infants with NEC. Secondary objectives 1. Measure cerebral oxygenation simultaneously with gut oxygenation. 2. Establish normal ranges for gut and cerebral oxygenation, and gut tissue biomarkers. 3 Methods Prospective observational study of 50 preterm infants born at <30 weeks gestation. Exclusion factors: Intrauterine Growth Restriction (IUGR), abnormal antenatal dopplers or significant congenital malformations. Each infant was monitored weekly until 36 weeks post conceptional age or discharge with 60 minute Near Infrared Spectroscopy (NIRS) measurements of splanchnic (sTOI) and cerebral (cTOI) oxygenation, stool calprotectin, urine intestinal (I-FABP) and liver (L-FABP) fatty acid binding protein, and trefoil factor 3 (TFF-3), and blood for Haemoglobin and Haemoglobin F (HbF). Weekly clinical status was recorded; NEC defined as ≥ Bells stage 2. Results • Mean cTOI (56.8-65.4%) was significantly higher (p<0.001) than mean sTOI (36.7-46%). • There was a wide variation in normal ranges of all four gut biomarkers. • There was no significant effect of Haemoglobin or RBCT on NIRS measurements or gut biomarkers. • There was no significant difference in any gut biomarker between those infants with and without NEC. • Infants with NEC had significantly lower sTOI and cTOI. 4 Conclusion Haemoglobin and RBCT had no effect on gut biomarkers or NIRS measurements, emphasising the complex relationship between Haemoglobin, perfusion and oxygenation. No gut tissue biomarkers were identified to predict NEC, but continuous NIRS monitoring could benefit clinicians by alerting them to the onset of NEC sooner.