Gastro-oesophageal reflux monitoring: Review and consensus report on detection and definitions of acid, non-acid, and gas reflux

Abstract

To date, most concepts on the frequency of gastro-oesophageal reflux episodes and the efficiency of the antireflux barrier have been based on inferences derived from measurement of oesophageal pH. The development of intraluminal impedance monitoring has highlighted the fact that pH monitoring does not detect all gastro-oesophageal reflux events when little or no acid is present in the refluxate, even if special pH tracing analysis criteria are used. The total rate of reflux episodes is an important indicator of the competence of the antireflux barrier and is therefore relevant when evaluating the effect of therapies directed at improving antireflux barrier function. In November 2002, a workshop took place at which 11 specialists in the field of gastro-oesophageal reflux disease (see list of contributors at the end of this article) discussed and criticised all currently available techniques for measurement of reflux. This paper presents a synthesis of their conclusions and recommendations of how to achieve the best results from the various techniques now available for reflux measurement. It was concluded that intraluminal impedance monitoring is the only recording method that can achieve high sensitivity for detection of all types of reflux episodes while pH-metry is required for characterisation of reflux acidity. However, the role of intraluminal impedance in the management of patients with gastro-oesophageal reflux disease still needs to be defined from appropriately designed clinical trials. The impact of new techniques on the definition of different types of reflux was also discussed extensively at the workshop, and new or slightly amended definitions are proposed - namely, "acid reflux", "superimposed acid reflux", "weakly acidic reflux", and "weakly alkaline reflux".