Tonometry. A review of clinical studies

In the quest for a better monitor of end-organ injury in the critically ill patient, gastrointestinal tonometry to measure intramucosal pH (pHi) and PCO2 has been advocated by several investigators. The authors discuss the principles and practice of gastric tonometry. In addition, the clinical applications of the technique are discussed with close attention to the use of pHi as an indicator of mucosal ischemia, ICU morbidity rates, and ICU mortality rates in surgical and medical patient populations. Although prognostic capability is an important role for tonometry, the principal benefit of the technology is its efficacy as an index of tissue resuscitation and as a guide to medical intervention. Given recent technical advances, gastrointestinal tonometry may gain increasing use in the assessment of tissue perfusion and oxygen metabolism.