Breath tests: preparation and implementation

Preparation and implementation of breath tests

• 13C breath test:  The patient must be fasting. He should not have eaten or smoked since 5:00 p.m. the day before, and had not drunk anything since 10:00 p.m. The breathing air is collected in a double-chamber bag, which the patient blows into using a mouthpiece. First, the initial value (“blank value”) is determined by blowing into the first chamber.
  Then 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 is sent to the laboratory. In the 13C-octanoic acid or sodium acetate breath test, the marked substance is administered in the form of a test meal and the exhaled air is collected every 15 minutes over a period of 4 hours.
• H2 breath test:  The patient must also be sober and a blank value is determined at the beginning. Then 200 ml of liquid is drunk with the corresponding test sugar. A breath sample is then taken every 10 minutes for a total of 3-4 hours, in which the hydrogen concentration is measured.

Further function test for gastrointestinal complaints

The time it takes for the contents of the intestine to pass through the large intestine can also be determined. This examination (Hinton test) can provide valuable information, especially in patients with chronic  constipation  and defecation disorders. Its advantage is that it is easy to carry out and relatively unstressful: the patient has to swallow 2 gelatine capsules at the same time each day for 6 days. They contain harmless, indigestible plastic beads that can be detected in an X-ray on the 7th day.

The number and distribution of these markers that have not yet been eliminated allow conclusions to be drawn about passage times and existing obstacles. In the case of specific suspected diagnoses such as bile acid loss syndrome,  vitamin B12 deficiency  or functional disorders of the  pancreas  , there are further special tests (e.g. Schilling test, 75SeHCat test, pancreolauryl test).