title: Intestinal blood flow by Doppler ultrasound: the impact of gestational age and time from first enteral feeding in preterm neonates.
abstract: OBJECTIVE
  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.
  
  
  METHODS
  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.
  
  
  RESULTS
  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.
  
  
  CONCLUSIONS
  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.
authors.affiliation: Division of Neonatology, Department of Pediatrics, Children's Hospital at Montefiore (Weiler Division), Bronx, New York.
authors.forename: Alecia
authors.initials: A
authors.lastname: Thompson
authors.affiliation: Division of Pediatric Imaging, Department of Diagnostic Radiology, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Cicero Torres
authors.initials: CT
authors.lastname: Silva
authors.affiliation: Division of Newborn Medicine, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: A Semih
authors.initials: AS
authors.lastname: Gork
authors.affiliation: Division of Biostatistics, Department of Epidemiology and Population Health, Albert Einstein College of Medicine, Bronx, New York.
authors.forename: Dan
authors.initials: D
authors.lastname: Wang
authors.affiliation: Division of Newborn Medicine, Department of Pediatrics, Yale University School of Medicine, New Haven, Connecticut.
authors.forename: Richard A
authors.initials: RA
authors.lastname: Ehrenkranz
mesh_terms: D001783:Blood Flow Velocity; D015331:Cohort Studies; D004750:Enteral Nutrition / Q000706:statistics & numerical data*; D005260:Female; D005865:Gestational Age; D006801:Humans; D062071:Infant, Extremely Premature; D007231:Infant, Newborn; D007234:Infant, Premature; D007422:Intestines / Q000098:blood supply*; D008297:Male; D017538:Mesenteric Artery, Superior / Q000000981:diagnostic imaging*; D011446:Prospective Studies; D012039:Regional Blood Flow; D018608:Ultrasonography, Doppler