Paradoxical impact of body positioning on gastroesophageal reflux and gastric emptying in the premature neonate.
OBJECTIVE
To combine manometry and impedance to characterize the mechanisms of gastroesophageal reflux (GER) and to explore their relation to the rate of gastric emptying (GE) and body position.


METHODS
Ten healthy preterm infants (35 to 37 weeks' postmenstrual age) were studied with the use of a micromanometric/impedance assembly. Episodes of GER were identified by impedance, and the mechanism(s) of GER triggering and GER clearance were characterized. GE was determined with a C13Na-octanoate breath test.


RESULTS
Gastroesophageal reflux episodes (n=89) were recorded, consisting of 74% liquid, 14% gas, and 12% mixed. Transient lower esophageal sphincter relaxation (TLESR) was the predominant mechanism of reflux, triggering 83% of GER. Of 92 TLESRs recorded, 27% were not associated with reflux. Infants studied in the right lateral position had significantly (P <.01) more GER, a higher proportion of liquid GER (P <.05), and faster GE (P <.005) when compared with infants studied in the left lateral position.


CONCLUSIONS
In healthy preterm infants, GER is predominantly liquid in nature. Right-side positioning is associated with increased triggering of TLESR and GER despite accelerating GE.
Department of Paediatrics, University of Adelaide, Center for Paediatric and Adolescent Gastroenterology, Neonatal Medicine Unit, Women's and Children's Hospital, North Adelaide Australia. taher.omar@adelaide.edu.au
Taher I
TI
Omari
Nathalie
N
Rommel
Esther
E
Staunton
Ros
R
Lontis
Louise
L
Goodchild
Ross R
RR
Haslam
John
J
Dent
Geoffrey P
GP
Davidson
D017097:Electric Impedance; D005260:Female; D005746:Gastric Emptying; D005764:Gastroesophageal Reflux / Q000503:physiopathology*; D006801:Humans; D007231:Infant, Newborn; D007235:Infant, Premature, Diseases / Q000503:physiopathology*; D008297:Male; D008365:Manometry; D011187:Posture; D013997:Time Factors