Development of a pH based tissue ischemia monitor: preliminary clinical results

The objective of the authors' research is to develop a pH measuring system which will be used for accurate postoperative monitoring of transplanted tissue. Currently, most pH monitors that are used for this purpose are difficult to operate by hospital personnel and do not possess sufficient long-term stability, resulting in false readings of tissue pH. To resolve these problems, an electronic multi-channel pH measuring device, that interfaces with a laptop computer, was constructed. The system makes use of an algorithm to compensate for instabilities that are inherent to pH measurements. This is accomplished using separate pH reference electrode channels from which multiple measurements are taken and averaged. Preliminary tests show that this system accurately measures tissue pH and remains stable during the 96 hour postoperative monitoring period.