153 - Impacts of Red Blood Cell Transfusion and Enteral Feeding on Mesenteric Regional Tissue Oxygenation Dynamics in Very Preterm Infants

Publication Number: 2147.153

Anand Salem, Emory University School of Medicine/Children's Healthcare of Atlanta, Atlanta, GA, United States; Joshua Lukemire, Emory University, Atlanta, GA, United States; Jocelyn Ou, Emory/Children's Healthcare of Atlanta, Atlanta, GA, United States; Maria E. Barbian, Emory University School of Medicine, Decatur, GA, United States; Natia Saakadze, Emory University School of Medicine, Atlanta, GA, United States; Jeanne E. Hendrickson, Emory University School of Medicine, DECATUR, GA, United States; Kirk A. Easley, Emory University, Atlanta, GA, United States; Cassandra Josephson, Medtronic, St. Petersburg, FL, United States; Ravi M. Patel, Children's Healthcare of Atlanta and Emory University, Atlanta, GA, United States

Background: Fecal calprotectin is an established biomarker of intestinal inflammation and is elevated in conditions such as necrotizing enterocolitis. Recent studies show that red blood cell (RBC) transfusion increases fecal calprotectin in anemic preterm infants, while also influencing tissue oxygenation measured by near infrared spectroscopy (NIRS).

Objective: The objective of this study was to characterize how RBC transfusion and enteral feeding perturb mesenteric regional oxygenation (mes-rSO2) variability and if these is associated with intestinal inflammation, as measured by fecal calprotectin.

Design/Methods: We conducted a secondary analysis of prospectively collected data from a cohort of infants with a birth weight ≤1250 g, over a 4-year period (2017-2021), across 3 hospitals in Atlanta. Infants underwent mes-rSO2 monitoring prior to and up to 48 hours after RBC transfusion with an FDA-cleared NIRS device. We used regression analysis to evaluate the relationships between the volume of enteral feeding prior to RBC transfusion, the variability of mes-rSO2 characterized by mean sample entropy, and post-transfusion fecal calprotectin levels (ug/g).

Results: We analyzed a cohort of 61 infants with a mean ( SD) gestational age of 26.8  1.9 weeks and birthweight of 827  170 g. We found no significant correlation between pre-transfusion volume of enteral feeding and post-transfusion mean mes-rSO2 sample entropy (R= 0.13, P= 0.21). We found a significant correlation between post-transfusion mean mes-rSO2 sample entropy and post-transfusion fecal calprotectin (R= 0.76, p=0.00068, Figure 1). The strength of this relationship was greatest 1 to 2 days post-transfusion (and attenuated with increasing days post-transfusion (Figure 2). We found no significant associations between post-transfusion mean mes-rSO2 saturation (MAUC) and post-transfusion fecal calprotectin (R= -0.016, p= 0.92, Figure 3).

Conclusion(s): Post-transfusion mesenteric oxygenation variability, as measured by mean sample entropy, is associated with post-transfusion intestinal inflammation. There does not appear to be an association between pre-transfusion enteral feeding volume and post-transfusion mesenteric oxygenation sample entropy. These findings highlight potential importance of physiologic time series data, rather than mean saturations, to characterize the effects of RBC transfusion on mesenteric oxygenation dynamics.

Figure 1. Relationship between Post-Transfusion Sample Entropy and Fecal Calprotectin
Post-transfusion sample entropy was significantly associated with post-transfusion log fecal calprotectin levels that was strongest up to two days post RBC transfusion (R=0.76, p=0.0068). The shaded region represents the 95% confidence interval for the mean.

Figure 2. Association between Post-Transfusion Sample Entropy and Fecal Calprotectin over Time
Association between Post-transfusion sample entropy and post-transfusion log Fecal Calprotectin level showing attenuation over time from transfusion. Panel A (left). 3-day window post transfusion (R= 0.41, p=0.042). Panel B (middle). 4-day window post transfusion (R= 0.31, p =0.09). Panel C (right). 6-day window post transfusion (R=0.19, p= 0.18). Shaded regions represent 95% confidence intervals for the mean.

Figure 3. Post-Transfusion Mean Mes-rSO2 not associated with Post-Transfusion Fecal Calprotectin
There is no association between Post-Transfusion mean Mes-rSO2 and post-transfusion log fecal calprotectin levels (R= -0.016, p= 0.92).