Mucosal saturation measurements in patients suspected for chronic gastrointestinal ischemia

The diagnosis chronic gastrointestinal ischemia (CGI) is often made a late
phase of the disease. This is explained by the fact that it is relatively rare
disease (in the Netherlands 50 - 150 patients / year), also diagnostics to
evaluate patients with possible CGI are cumbersome, special equipment is
required and some experience is necessary. The past decade, gastrointestinal
tonometry has proved to be of major importance in the diagnosis of CGI. The
principle of tonometry is the measurement of intraluminal CO2, which is
elevated in patients with CGI. Combined with anatomical investigation (CT- or
MR-angiography) the diagnosis CGI can be made with an acceptable sensitivity
and specificity. The major disadvantage of tonometry are invasive (2 catheters
have to be placed in stomach and jejunum) and longer durations (upto 24 hours).
Furthermore, is tonometry cumbersome: some experience with the technique is
necessary. The tonometry technique is relatively unknown, also it does not
resemble any technique currently used in the field of gastroenterology. This,
and the forementioned disadvantages, make that tonometry is still not accepted
as a common diagnostic technique and is only used in a few clinics for this
purpose.

Recently, a new endoscopic technique for measurement of mucosal oxygen
saturation has become available. This mucosal saturation of stomach and small
bowel mucosa seems directly related to the overall bloodflow in these organs.
In a recent article this technique proves of value in a small number of
patients with CGI.

Evaluation of the diagnostic value of stomach and small bowel mucosal oxygen
saturation measurements in patients suspected for chronic gastrointestinal
ischemia.
Determination of normal mucosal oxygen saturation values in patients without
chronic gastrointestinal ischemia or a gastrointestinal vascular stenosis.

Prospective; comparison of results of mucosal saturation measurements with the
results of the standard work-up (tonometry, CT/MR-angiography and consensus
diagnosis of the workinggroup on chronic gastrointestinal ischemia).

1) the duration of the gastroduodenoscopy will be a few minutes longer; the
overall risk of the measurements is very low (almost zero).
2) patients having a control gastroduodenoscopy after treatment:
- burden: repeated gastroduodenoscopy
- risks: comparable to the overall risk of a diagnostic gastroduodenscopy (very
low; 1 : 3000).

Duplex ultrasound in patients without chronic gastrointestinal ischemia or a
gastrointestinal vascular stenosis is a non-invasive procedure without risks.