Twenty four hour intragastric acidity analysis for the future.

Twenty four hour intragastric acidity analysis for the future Studies of 24 hour intragastric acidity have been useful in the investigation of effects of diet,' 2 and drugs on gastric acidity in ulcer patients 3 and normal volunteers.14-17 8] These conditions are easily reproduced and thus comparative studies are possible. The technique is labour intensive, however, and has some disadvantages. During the day only acidity is measured, as it is not possible to assess the volume of gastric secretion. Duodenogastric reflux almost certainly occurs, but cannot be estimated. Complete collections of gastric juice are sometimes made at night, to allow assessment of nocturnal secretion. Nocturnal acidity assessed in this way, however, poorly reflects 'real life' acidity because of continual aspiration of gastric contents. When small numbers of replicate studies have been done the results have been reasonable1 2 814 but the exact reproducibility and the magnitude of error implicit in the studies has not been accurately determined.