Identical 24-hour gastric pH profiles when using intragastric antimony or glass electrodes or aspirated gastric juice.

Intragastric pH was continuously measured over 24 h with a monocrystalline antimony electrode system and was compared with pH measured in simultaneously aspirated gastric juice and with pH measured by using a conventional intragastric glass electrode. There was a marked correlation between the pH readings obtained with the monocrystalline antimony electrode and the pH values measured in aspirated gastric juice (r = 0.92, p less than 0.001) and with the pH readings obtained with the intragastric glass electrode (r = 0.92, p less than 0.001). Both readings of pH with glass electrode and of pH after aspiration can be predicted by readings of pH with antimony electrode by using linear regression lines with slopes close to 1. Intragastric pH measurement is an alternative to aspiration of gastric juice, and the result obtained with an electrode of monocrystalline antimony is comparable to that obtained with a conventional glass electrode.