Jejunal tonometry for the diagnosis of gastrointestinal ischemia. Feasibility, normal values and comparison of jejunal with gastric tonometry exercise testing.

Abstract

In most patients with chronic splanchnic syndrome the celiac artery is involved, enabling the use of gastric exercise tonometry as a diagnostic function test. In this study, we investigated the feasibility of combining gastric and jejunal exercise tonometry and determined the normal values. We investigated the potential diagnostic value of combining gastric with jejunal exercise tonometry.
Between 1998 and 2000, combined gastric and jejunal exercise tonometry tests were performed in a healthy volunteer and in patients suspected of chronic gastrointestinal ischemia. Using automated air tonometry, gastric (PgCO2) and jejunal PCO2 (PjCO2) were measured before, during and after 10-min of exercise. Luminal-arterial PCO2 gradients (DeltagPCO2 respectively DeltajPCO2) were calculated. In the patient cohort, final diagnosis of chronic ischemia was made by our institutional multidisciplinary working group on gastrointestinal ischemia.
Jejunal tonometry was possible in 25 of 27 participants. The healthy volunteer was tested twice, yielding a total of 26 combined tests. Mean normal basal PjCO2 was 0.9 kPa higher than PgCO2. The calculated upper threshold (mean+2SD) of normal DeltajPCO2 was 1.4 kPa. In five of eight patients with chronic gastrointestinal ischemia gastric exercise tonometry was abnormal, in one, both gastric and jejunal tonometry were abnormal, in two only jejunal exercise tonometry was abnormal.
Combined gastric and jejunal exercise tonometry is a feasible procedure that is relatively easy to perform. On the basis of this pilot study, jejunal tonometry seems to have a small additional value in the diagnosis of chronic gastrointestinal ischemia.