Gastro-oesophageal reflux--initial experience with a radiotelemetry system for prolonged oesophageal pH monitoring.

A radiotelemetry system has been used to monitor gastro-oesophageal reflux over a prolonged period in 27 asymptomatic control subjects and in 15 patients with reflux symptoms. In control subjects, the frequency of reflux episodes (pH < 5) ranged from 0.1 - 0.7 per hour of recording (median 0.36) by day, and from 0 - 1.0 per hour (median 0.12) by night. The duration of reflux (pH < 5) per hour of recording ranged from 0.4 - 5.4 minutes (median 2.1) by day and from 0 - 5.1 minutes (median 0.27) by night. Patients with reflux symptoms had more frequent episodes of daytime reflux and a longer duration of daytime reflux than control subjects. The frequency and duration of nocturnal reflux were similar in patients and in control subjects. Of two patients with Barrett's metaplasia of the lower oesophagus, one had markedly increased frequency and duration of both daytime and nocturnal acid reflux, while the other had only a moderate increase in the frequency of daytime reflux episodes.