Serial Doppler velocimetry of mesenteric and portal flow in very-low-birth-weight preterm neonates with and without patent ductus arteriosus

Efficacy of bowel ultrasound to diagnose necrotizing enterocolitis in extremely low birthweight infants

BACKGROUND

Bowel ultrasound (US) is one of the methods used to enhance diagnostic accuracy of necrotizing enterocolitis (NEC) and its associated complications in premature newborns.

AIM

To explore the diagnostic accuracy of bowel US in extremely low birth weight (ELBW) infants with NEC.

METHODS

A single-center retrospective case-control study included 84 extremely low birth weight (ELBW) infants. The infants were divided into three groups: Group 1 -infants with NEC (n = 26); Group 2 -infants with feeding problems (n = 28); Group 3 -control group (n = 30).

RESULTS

The specific bowel US findings in premature newborns with NEC (stage 3) included bowel wall thinning, complex (echogenic) ascites, and pneumoperitoneum, p < 0.05. The diagnostic effectiveness of these sonographic signs was 96.8% (sensitivity 75.0% and specificity 97.6%), p < 0.05. These findings with high specificity were associated with the need for surgical intervention, poor outcomes, or increased mortality. Stage 2 NEC which did not require surgery showed impaired differentiation of the bowel wall layers, absent or decreased bowel peristalsis, pneumatosis intestinalis, portal venous gas, or simple ascites, with a diagnostic accuracy of 82.9% (sensitivity 55.6%, specificity 91.4%, p < 0.05).

CONCLUSIONS

Bowel US can be used as an adjunct to abdominal radiography to aid in the diagnosis of infants with suspected NEC by providing more detailed evaluation of the intestine.

Nutrition of the preterm infant with persistent ductus arteriosus: existing evidence and practical implications

The persistence of a patent ductus arteriosus (PDA) is a common condition in preterm infants with a prevalence inversely proportional to gestational age. PDA is associated with mild-to-severe gastrointestinal complications such as feeding intolerance, gastrointestinal perforation, and necrotizing enterocolitis, which represent a major challenge for the nutritional management in preterm infants. In this context, the Section on Nutrition, Gastroenterology and Metabolism and the Circulation Section of the European Society for Pediatric Research have joined forces to review the current knowledge on nutritional issues related to PDA in preterm infants. The aim of the narrative review is to discuss the clinical implications for nutritional practice. Because there is little literature on postnatal nutrition and PDA in preterm infants, further research with well-designed studies on this topic is urgently needed. Guidelines should also be developed to clearly define the implementation and course of enteral nutrition and the target nutritional intake before, during, and after pharmacologic or surgical treatment of PDA, when indicated. IMPACT: Persistent ductus arteriosus (PDA) is associated with gastrointestinal complications such as feeding intolerance, gastrointestinal perforation, and necrotizing enterocolitis, which pose a major challenge to the nutritional management of preterm infants. In PDA infants, fluid restriction may lead to inadequate nutrient intake, which may negatively affect postnatal growth and long-term health. The presence of PDA does not appear to significantly affect mesenteric blood flow and splanchnic oxygenation after enteral feedings. Initiation or maintenance of enteral nutrition can be recommended in infants with PDA.

Neonatal anemia relates to intestinal injury in preterm infants

BACKGROUND

Anemia is associated with decreased tissue oxygenation in preterm infants and may contribute to developing necrotizing enterocolitis (NEC). We aimed to investigate whether hemoglobin level is associated with intestinal injury, by comparing anemic infants 10 days prior to red blood cell (RBC) transfusion with non-anemic controls.

METHODS

A nested case-control study in which we matched anemic preterms (gestational age (GA) < 32 weeks) with non-anemic controls (1:1), based on GA, birth weight (BW), and postnatal age. We measured urinary intestinal fatty acid-binding protein, I-FABP, marker for intestinal injury, twice weekly. Simultaneously, we assessed splanchnic oxygen saturation (r_sSO₂) and r_sSO₂ variability.

RESULTS

Thirty-six cases and 36 controls were included (median GA 27.6 weeks, BW 1020 grams). Median I-FABP level was higher in cases from 6 days to 24-h before transfusion (median ranging: 4749-8064 pg/ml versus 2194-3751 pg/ml). R_sSO₂ and r_sSO₂ variability were lower in cases than controls shortly before transfusion. Hemoglobin levels correlated negatively with r_sSO₂ and r_sSO₂ variability in cases, and negatively with I-FABP in cases and controls together.

CONCLUSIONS

Urinary I-FABP levels were higher in anemic infants before RBC transfusion than in non-anemic matched controls, suggesting intestinal injury associated with anemia. This may predispose to NEC in some anemic preterm infants.

IMPACT

Anemia is a common comorbidity in preterm infants and may lead to impaired splanchnic oxygen saturation and intestinal tissue hypoxia, a proposed mechanism for NEC. Lower hemoglobin level is associated with higher urinary I-FABP levels, a marker for intestinal injury, both in anemic preterm infants and in cases and controls together. Lower splanchnic oxygen saturation and reduction of its variability are associated with higher urinary I-FABP levels in anemic preterm infants before their first RBC transfusion. These results support the hypothesis that anemia in very preterm infants results in intestinal cell injury, which may precede NEC development in some.