MATURATION OF THE LOWE OESOPHAGEAL SPHINCTER IN THE PRE-TERM NEONATE

Abstract

Gastro-oesophageal reflux (GOR) is a common problem in pre-term neonates, yet little is known about the maturation of the lower oesophageal sphincter (LOS). We have studied the development of the LOS using a manometric technique in non-ventilated neonates; post conceptional age (PCA) 26-40 wk, weighing 0.7-4.4 kg. Immediately before a feed an end opening 1.5mm external diameter catheter was passed per nasally into the oesophagus and the pressure measured as it was advanced through the LOS. “Effective sphincter pressure” (ESP) was calculated as LOS pressure minus gastric fundal pressure: In contrast to previous studies, there was a close correlation between ESP and PCA (p<<0.001). The correlation of ESP with post natal age and weight was less marked though still significant (p<0.01). These findings offer a rational explanation for the high incidence of GOR in pre-term infants.