Acid oro-pharyngeal secretions can predict gastro-oesophageal reflux in preterm infants

Acid gastro-oesophageal reflux (GOR) is common in preterm infants but there is a lack of a non-invasive technique to establish the diagnosis. The aim of this study was to identify whether the presence of acid in ore-pharyngea l secretions (OPS) was a valid indicator of clinically significant acid GOR in preterm infants. A total of 23 infants with suspected GOR were studied with 24 h lower-oesophageal pH monitoring and during this period the OPS we re tested for acid with litmus paper at 6 hourly intervals. Median (range) gestation was 28 weeks (24-31), birth weight 1023 g (480-1750) and age at s tudy 34 days (11-76). Significant GOR was defined as a reflux index > 5%. O f the investigated infants, 18 subjects (78%) had significant GOR. Of this group, 16 infants had acid in the OPS on at least one occasion. Five infant s did not demonstrate significant GOR and in four of these acid was not det ected in the OPS. Our data indicate that as a predictor for significant GOR , litmus-testing OPS for acid has a sensitivity of 89%, specificity of 80%, positive predictive value of 94% and a negative predictive value of 67%. T he difference in the incidence of acid OPS between the GOR and the No GOR g roup was significant (P < 0.03). Conclusion The presence of acid in the oropharyngeal secretions may help in the prediction of acid gastro-oesophageal reflux in preterm infants. The m ethod is simple, inexpensive cheap and involves minimal disturbance. We sug gest that it could aid clinical diagnosis and indicate a need for further i nvestigation of gastro-oesophageal reflux.