Intestinal Blood Flow by Doppler Ultrasound: The Impact of Gestational Age and Time from First Enteral Feeding in Preterm Neonates

Abstract

To explore whether superior mesenteric artery (SMA) peak systolic velocity (PSV) on Doppler ultrasound varies by gestational age (GA) and time from first enteral feeding and has an impact on feeding intolerance. Preterm neonates were assigned to three GA groups at birth, group I: 31 to 356/7 weeks, group II: 27 to 306/7 weeks, and group III: ≤ 266/7 weeks. SMA PSV and clinical and feeding parameters were assessed before and after enteral feed, with the first enteral feed designated as time 1, time 2 = 1 to 4 days (after first feed), time 3= 5 to 7 days, time 4 = 8 to 14 days, and time 5 = 15 to 28. Forty-one patients completed the study (group I: n = 17, group II: n = 12, group III: n = 12). There was no significant difference in SMA PSV change after feeding between groups at the start of enteral feeding (p = 0.12). There were differences in change in SMA PSV after feeding at times 2, 3 and 5 (p = 0.003, p = 0.004, p = 0.009, respectively). Patients with feeding intolerance exhibited a smaller increase in SMA PSV after feeding. There were significant differences in PSV by GA group. SMA PSV change after feeding was lower in patients who had feeding intolerance compared with those who did not.