Abstract

Measurement of gastro intestinal intramucosal pH (pH_im) has been recognised as an important factor in the detection of hypoxia induced dysfonctions. However, current pH measurement techniques are limited in terms of time and spatial resolutions. A major advance in accurate pH measurement was the development of the ratiometric fluorescent indicator dye, 2',7'-bis(carboxyethyl)-5,6-carboxyfluorescein (BCECF). BCECF which pK_a is in the physiological pH range is suitable for in vivo pH tissue measurement. This study aimed to develop and evaluate an endoscopic imaging system for real time pH measurement in the stomach in order to provide to ICU a new tool for gastro intestinal intramucosal pH (pH_im) measurement. This fluorescence imaging technique should allow the temporal exploration of sequential events, particularly in ICU where the pHim provides a predictive information of the patient' status. The experimental evaluations of this new and innovative endoscopic fluorescence system confirms the accuracy of pH measurement using BCECF.

© 2003 SPIE