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Experience with sham feeding as a test for vagotomy
Gastroenterology
|November 1, 1980
Summary
Sham feeding can assess vagotomy effectiveness. A low ratio of sham feeding-stimulated to peak acid output suggests successful vagotomy, while a normal ratio indicates persistent vagal innervation.
Area of Science:
- Gastroenterology
- Surgical Efficacy Assessment
Background:
- Vagotomy is a surgical procedure to reduce gastric acid secretion.
- Sham feeding is believed to stimulate gastric acid secretion exclusively through vagal pathways.
Purpose of the Study:
- To determine if sham feeding can serve as a reliable test for evaluating the success of vagotomy.
- To establish a quantitative measure for assessing vagal innervation after surgery.
Main Methods:
- Established a ratio of sham feeding-stimulated acid output to peak acid output (SF/PAO) in non-vagotomized subjects.
- Defined a SF/PAO ratio of 0.10 or less as abnormally low with 95% confidence.
- Applied this ratio to assess vagotomy success in duodenal ulcer patients.
Main Results:
- A low SF/PAO ratio (≤0.10) was observed in 68% of vagotomized patients without recurrent ulcers, indicating effective vagotomy.
- A normal SF/PAO ratio (>0.10) was found in 73% of vagotomized patients with recurrent ulcers, suggesting incomplete vagotomy.
- Reproducibility of the SF/PAO ratio was confirmed in repeated tests on the same patients.
Conclusions:
- A SF/PAO ratio greater than 0.10 after vagotomy suggests incomplete denervation.
- A SF/PAO ratio of 0.10 or less provides a reliable indicator (≥95% confidence) of successful vagotomy.
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