Preparation and execution of breath tests
- 13C breath test: The patient must be fasted. He had not eaten and smoked since 17:00 the day before, since 22:00 clock have drunk nothing. The breathing air is collected in a double-chamber bag, into which the patient blows with a mouthpiece. First, the initial value ("blank value") is determined by blowing into the first chamber.
Thereafter, the capsule containing the labeled urea is dissolved in 200 ml of apple or orange juice and drunk. After half an hour, the other side of the bag is inflated. The carefully sealed bag will be sent to the laboratory. In the 13C octanoic acid or sodium acetate breath test, the labeled substance is administered as a test meal and the exhaled air is collected every 15 minutes for 4 hours.
- H2 breath test: Again, the patient must be fasting and at the beginning of a blank is determined. Then 200 ml of liquid are drunk with the corresponding test sugar. Subsequently, a breath sample is obtained every 10 minutes for a total of 3-4 hours, in which the hydrogen concentration is measured.
Further functional test for gastrointestinal complaints
Also, the time it takes for the intestinal contents to pass through the colon can be determined. This study (Hinton test) can provide valuable information, especially in patients with chronic constipation and defecation disorders. Its advantage is that it is easy to perform and relatively inexpensive: the patient must swallow 2 gelatin capsules at the same time for 6 days at a time. They contain harmless, indigestible plastic globules, which are detected on the 7th day in an X-ray.
Due to the number and distribution of these not yet eliminated markers conclusions about passage time and existing obstacles are possible. For specific suspected diagnoses such as bile acid loss syndrome, vitamin B12 deficiency or dysfunction of the pancreas, there are further specific examinations (eg shilling test, 75SeHCAt test, pancreolauryl test).