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Gastric Analysis


Jonathan Gotfried

, MD, Lewis Katz School of Medicine at Temple University

Last full review/revision Apr 2021| Content last modified Sep 2022
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Gastric acid analysis is rarely done in current practice. When conducted, samples of stomach contents obtained via nasogastric tube are used to measure gastric acid output in a basal and stimulated state. This information may be useful in a patient who develops a recurrent ulcer Surgery Surgery after surgical vagotomy for peptic ulcer disease. In this case, a positive acid response to stimulation (sham feeding) indicates an incomplete vagotomy.

To do gastric analysis, a nasogastric tube is inserted and the gastric contents are aspirated and discarded. Gastric juice is then collected for 1 hour, divided into four 15-minute samples. These samples represent basal acid output.

Complications of gastric analysis are very rare.

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