Color Doppler Blood Flow Indices of the Superior Mesenteric Artery as an Early Predictor of Necrotizing Enterocolitis in Preterm Neonates

Abstract

Abstract:Background: Necrotizing enterocolitis is the most common sever gastrointestinal emergency that affects premature newborns. It is often has a rapid onset with few signs that can be used to predict its occurrence. Its rapid onset and progression to morbidity and mortality initiates the researchers for seeking early diagnostic tools helping in detection infants at risk for development of the disease, for whom early preventive measures could be targeted. Previous studies have shown that high resistance patterns of mesenteric arterial Doppler flow velocimetry are associated with a significantly reduced tolerance to enteral feeding. Moreover, groups of infants deemed to be at increased risk of necrotizing enterocolitis tended to have high resistance patterns of flow in the superior mesenteric artery. AIM: To evaluate the Doppler blood flow indices of the superior mesenteric artery (SMA) in pre-term neonates at risk for developing necrotizing enterocolitis (NEC). Materials and Methods: This prospective study included 52 preterm neonates, whose gestational age was less than 34 weeks. All of the neonates were subjected to clinical assessments, laboratory investigations and color Doppler flow evaluation of the SMA (including PSV, EDV, RI and PI) on the first day of life. Necrotizing enterocolitis was diagnosed and classified based on Bell's staging criteria with Walsh and Kliegman's modifications. Clinical management and diagnosis of NEC were performed blind to the Doppler results. Statistical analysis was performed using the Mann-Whitney U test, and P-values less than or equal to 0.05 were statistically significant. Receiver operating characteristic (ROC) curves were used to determine the optimal threshold values of PSV, EDV, RI and PI, using MedCalc software, version 12.7.8.0. Results: The study included 52 preterm neonates, whose gestational age was less than 34 weeks. Twelve neonates (23%) developed NEC and were designated as group I, and the remaining 40 neonates (77%) were designated as group II. The median birth weights in groups I and II were 1000 and 1870 g, respectively, with a statistically significant difference of P < 0.05. Doppler indices of the SMA, peak systolic velocity (88.9 ±17 and 53 ±8.5 cm/s), end diastolic velocity (18.75±11.3 and 14.9±5.6 cm/s), resistive index (0.78±0.09 and 0.67±0.1) and pulsatility index (1.53±0.73 and 0.67 ± 0.15) were higher in group I than in group II, with statistically significant differences. Conclusion: Preterm infants with high resistance patterns of blood flow velocity in the SMA on the first day of life were at increased risk for developing necrotizing enterocolitis.

Doppler flowmetry of the superior mesenteric artery and portal vein: impact for the early prediction of necrotizing enterocolitis in neonates

“…Recently several studies found that neonates with NEC have a significant increase in flow velocity in the SMA in comparison with the healthy ones during the first day of life [1,5]. However, our results did not reveal a significant difference in SMA flowmetry parameters.…”

“…However, our results did not reveal a significant difference in SMA flowmetry parameters. The same studies have shown that infants with risk factors for NEC tend to have higher resistance pattern [1,5]. This supports the role of the decreased intestinal blood flow in the pathogenesis of NEC.…”

“…Necrotizing enterocolitis (NEC) is the most common serious gastrointestinal disorder affecting preterm infants [1]. It affects 1-8 % of all infants admitted to the neonatal intensive care unit and its mortality rate can reach 10-50 % [2].…”

A systematic review and meta-analysis of the role of Doppler ultrasonography of the superior mesenteric artery in detecting neonates at risk of necrotizing enterocolitis

“…Overall, a total of 494 neonates were included, among whom 126 developed NEC, while 368 neonates comprised the control group. Neonates in four studies were both term and preterm [ 11 , 13 , 20 , 24 ], whereas four studies only examined preterm neonates [ 12 , 18 , 21 , 22 ]. In four studies [ 11 , 20 – 22 ], there were no differences in gestational age or birth weight between the neonatal groups examined; in two studies [ 13 , 18 ], gestational age was similar, but birth weight was significantly lower in neonates with NEC compared to those without NEC; two studies [ 12 , 24 ] did not report P -values for either gestational age or birth weight.…”

“…Neonates in four studies were both term and preterm [ 11 , 13 , 20 , 24 ], whereas four studies only examined preterm neonates [ 12 , 18 , 21 , 22 ]. In four studies [ 11 , 20 – 22 ], there were no differences in gestational age or birth weight between the neonatal groups examined; in two studies [ 13 , 18 ], gestational age was similar, but birth weight was significantly lower in neonates with NEC compared to those without NEC; two studies [ 12 , 24 ] did not report P -values for either gestational age or birth weight. Furthermore, two studies [ 12 , 22 ] reported no difference in the incidence of patent ductus arteriosus, whereas the remaining six studies [ 11 , 13 , 18 , 20 , 21 , 24 ] provided no data regarding the hemodynamic parameters between the aforementioned groups of neonates.…”