Gastric aspiration technique for pH recording: a critical evaluation of this method.

The most often used methods for the measurement of intragastric acidity are repeated mostly hourly aspirations of gastric contents or continuous pH measuring with an electrode. Intragastric pH, volume of aspirated gastric juice and total acid secretion have been tested over relatively short periods of time (2-12 h) and through an entire 24-hour period. Nearly every clinical antiulcer drug which neutralizes acidity or inhibits acid secretion has been investigated with this method. pH monitoring with the gastric aspiration procedure is a reliable and reproducible method. There is a remarkable global agreement in the results. While pH electrodes provide an alternative means of measuring pH, they have the disadvantage of not allowing measurement of volume and/or acid secretion.