Lessons learned from intragastric pH monitoring

Management of gastroesophageal reflux disease (GERD) is based on the concept that gastric contents, principally acid and pepsin, are responsible for esophageal injury and symptoms of reflux disease. Pharmacologic management in the year 2001 revolves around the basic principle that control of intragastric pH correlates with esophageal healing and, subsequently, symptom relief. Although the majority of patients respond to a single daily dose of a proton pump inhibitor, many patients with reflux disease are "refractory" even to twice daily doses of these drugs. Potential reasons for this less than optimal response can be found when carefully examining the intragastric pH responses of healthy subjects and patients with GERD to these agents when taken at various times of the day, in proximity to meals, and in higher doses. In the past several years, we have explored many of these issues in attempting to understand the mechanisms behind incomplete response to proton pump inhibitors, using combined intragastric and intraesophageal pH monitoring. The "lessons learned" from these and supportive studies are the subject of this review.