Fatores associados à transfusão de concentrado de hemácias em recém-nascidos prétermo de muito baixo peso

Abstract

Red blood cell transfusion is a frequent intervention in very low birth weight preterm newborns and is associated with hematologic immaturity and greater clinical severity in these patients. Objective: to identify maternal, obstetric, and neonatal factors associated with red blood cell transfusion in very low birth weight preterm newborns, including the evaluation of a possible association with oropharyngeal colostrum immunotherapy. Method: an exploratory retrospective observational study was conducted using secondary analysis of data from 85 mother-infant dyads previously collected in a public neonatal hospital unit. Very low birth weight preterm newborns (VLBW-PTNB) with birth weight ≤ 1,500 g and gestational age < 37 weeks were included. Sociodemographic, maternal, and neonatal characteristics were described and compared according to the occurrence of red blood cell transfusion within the first 28 days of life, and prevalence ratios (PR) were estimated in the bivariate analysis. To identify factors independently associated with the outcome, multivariate binary logistic regression was performed, including birth weight (continuous variable), duration of mechanical ventilation ≥ 7 days, use of total parenteral nutrition > 10 days, and oropharyngeal colostrum immunotherapy, with adjustment for potential confounding factors. Analyses were performed using IBM SPSS Statistics software, version 22.0. Results: among the 85 newborns evaluated, 30 (35.3%) received at least one red blood cell transfusion within the first 28 days of life. In the bivariate analysis, gestational age < 28 weeks (PR = 2.81; 95%CI: 1.61–4.91), birth weight < 1,000 g (PR = 2.86; 95%CI: 1.57–5.21), mechanical ventilation ≥ 7 days (PR = 4.51; 95%CI: 1.73–11.75), late-onset sepsis (PR = 1.86; 95%CI: 1.05–3.27), and mortality (PR = 2.17; 95%CI: 1.22–3.84) were associated with higher prevalence of transfusion. In the multivariate analysis, higher birth weight was the only factor independently associated with lower probability of transfusion (adjusted OR = 0.996 per gram; 95%CI: 0.993–0.999; p = 0.017), indicating a progressive reduction in transfusion probability as birth weight increased. Prolonged use of total parenteral nutrition (> 10 days) showed greater magnitude of association with the outcome (adjusted OR = 2.20; 95%CI: 0.91–5.32; p = 0.080), although without statistical significance after adjustment. Prolonged mechanical ventilation (≥ 7 days) (adjusted OR = 3.02; 95%CI: 0.69–13.13; p = 0.141) and oropharyngeal colostrum immunotherapy (adjusted OR = 0.77; 95%CI: 0.24–2.45; p = 0.658) were not independently associated with the outcome. Conclusion: higher birth weight was the main independent protective factor against the need for red blood cell transfusion in very low birth weight preterm newborns, whereas oropharyngeal colostrum immunotherapy was not associated with this outcome. As technical products of the study, an educational booklet and a clinical flowchart were developed for neonatal healthcare professionals, aiming to support decision-making regarding transfusion in very low birth weight preterm newborns.