title: Characterization of anorectal pressure and the anorectal inhibitory reflex in healthy preterm and term infants.
abstract: OBJECTIVE
  To evaluate anorectal motor function in healthy premature and term infants with the use of micromanometric techniques.
  
  
  METHODS
  Anorectal manometry was performed in 22 healthy neonates (9 female) with a mean postmenstrual age of 32 weeks (range, 30 to 38 weeks) with a micromanometric anorectal assembly (od 2.0 mm). The assembly incorporated a 2-cm-long sleeve sensor for measurement of resting anal sphincter pressures and relaxation, and 4 sideholes recorded anal and rectal pressures. Rectal distension was performed with a latex balloon or direct air insufflation to elicit the anorectal inhibitory reflex (AR).
  
  
  RESULTS
  The mean anal sphincter pressure, rectal pressure, and rhythmic wave frequency were 40 mm Hg (range, 7 to 65 mm Hg), 11 mm Hg (range, 1 to 27 mm Hg), and 10/min (range, 8 to 14/min), respectively. A normal AR could be elicited in 21 of the 22 infants studied.
  
  
  CONCLUSIONS
  An anorectal micromanometric sleeve catheter is suitable for use in evaluating anorectal pressures in preterm and term neonates. Insufflation of air without the use of a balloon to elicit the AR is reliable and suitable for use in infants <34 weeks. Premature infants older than 30 weeks' postmenstrual age have normal anorectal pressures and a normal AR.
authors.affiliation: Department of Pediatric Gastroenterology & Nutrition, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: M A
authors.initials: MA
authors.lastname: Benninga
authors.forename: T I
authors.initials: TI
authors.lastname: Omari
authors.forename: R R
authors.initials: RR
authors.lastname: Haslam
authors.forename: C P
authors.initials: CP
authors.lastname: Barnett
authors.forename: J
authors.initials: J
authors.lastname: Dent
authors.forename: G P
authors.initials: GP
authors.lastname: Davidson
mesh_terms: D001003:Anal Canal / Q000502:physiology*; D000704:Analysis of Variance; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008297:Male; D008365:Manometry / Q000295:instrumentation / Q000379:methods*; D011312:Pressure; D012018:Reflex