title: Influences of breast milk composition on gastric emptying in preterm infants.
abstract: OBJECTIVE
  The aim of the present study was to determine whether specific biochemical and energy concentrations influence gastric emptying of unfortified and fortified mother's own milk (MOM) in stable preterm infants, and whether gastric emptying differs between feeds of unfortified MOM and feeds fortified with S-26 or FM 85 human milk fortifier (HMF) when infants are fed the same volume under similar conditions. Influences of infant gestation, age, and weight, and feed characteristics were also explored.
  
  
  METHODS
  Stomach volumes of 25 paired unfortified and fortified MOM feeds were monitored prefeed and postfeed delivery and at 30-minute intervals thereafter. For each feed, MOM samples were analyzed to determine concentrations of total protein, casein, whey, carbohydrate, lactose, fat, and energy. Fortified feed compositions were calculated by adding fortifier biochemical and energy concentrations to unfortified MOM concentrations. Ultrasound images were used to calculate infant stomach volumes. Statistical comparisons were made of paired stomach volume measurements.
  
  
  RESULTS
  Higher feed concentrations of casein were associated with faster gastric emptying during feed delivery (P = 0.007). When compared with unfortified MOM, S-26 fortified feeds emptied similarly, whereas FM 85 fortified feeds emptied more slowly both during feed delivery and during the postprandial period (P = 0.002, <0.001, respectively). Gastric emptying was slower for 2-hourly feeds compared with that for 3-hourly feeds (P = 0.003) and in supine position compared with that in prone (P = 0.001).
  
  
  CONCLUSIONS
  Breast milk composition influences gastric emptying in stable preterm infants, with feeds of higher casein concentration emptying faster during feeding than otherwise equivalent feeds, and FM 85 fortified MOM emptying more slowly than unfortified MOM.
authors.affiliation: *School of Chemistry and Biochemistry †Centre for Neonatal Research and Education, School of Paediatrics and Child Health, the University of Western Australia, Crawley, WA, Australia.
authors.forename: Sharon L
authors.initials: SL
authors.lastname: Perrella
authors.forename: Anna R
authors.initials: AR
authors.lastname: Hepworth
authors.forename: Karen N
authors.initials: KN
authors.lastname: Simmer
authors.forename: Donna T
authors.initials: DT
authors.lastname: Geddes
mesh_terms: D002364:Caseins / Q000032:analysis / Q000494:pharmacology; D004435:Eating / Q000502:physiology; D004750:Enteral Nutrition; D005260:Female; D005527:Food, Fortified; D005746:Gastric Emptying / Q000187:drug effects; D005865:Gestational Age; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology*; D008297:Male; D008895:Milk, Human / Q000737:chemistry*; D009929:Organ Size; D019518:Postprandial Period; D016684:Prone Position / Q000502:physiology; D013270:Stomach / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D016683:Supine Position / Q000502:physiology; D013997:Time Factors; D014463:Ultrasonography
chemical_list: D002364:Caseins