48. GASTRO-OESOPHAGEAL REFLUX IN THE PRE-TERM INFANT

Abstract

As the incidence, severity, and natural history of gastro-oesophageal reflux (GOR) in preterm infants is unknown we have studied GOR in this population. Continuous intraoesophageal pH was monitored over 24 hours using a novel 1mm antimony pH electrode (Synectics Medical). Electrode position was determined following identification of the lower oesophageal sphincter (LOS) by maronetry and the LOS pressure (LOSP) measured. 51 measurements were made on 29 patients (post-conceptional age (PCA): median 31, range 26-39 weeks). Mean (± SEM) indices of GOR were as follows: 12.1±2 episodes of GOR per 24 h; pH was < 4 for 4% ±0.9% of the total time; the longest episode during each recording was 17 ±4.6 min. The effect of various events upon GOR was assessed by analysing the amount of QOR occurring during a 30 min period including and following that event. This was compared with GOR during periods of rest. GOR was most likely to occur at the time of physiotherapy, orcpharyngeal suction, and nappy change (each p<0.001), and was increased after feeds (0.05<p<0.1). Reflux was slightly increased in the left lateral position compared with right lateral and prone positions, but this was not significant. There was no correlation between GOR end PCA, gestation, or LOSP. Infants receiving xanthine for apnoea had a twofold increase in GOR (p<0.05). A subgroup of six infants with recurrent apnoea unresponsive to xanthine had markedly higher mean GOR indices than all other infante studied (p<0.001). A rapid reduction in the frequency of apnoea followed abolition of GOR with thickened feeds.