[Clinical usefulness of gastric tonometry in anesthesiology and intensive care medicine]

Abstract

Gastric tonometry is relatively non-invasive technique to assess gastric perfusion and to monitor oxygen metabolism in visceral system. The technique utilizes the PCO2 of the gastric fluid to calculate intramucosal pH (pHi). The calculation is assessed by a modified Henderson-Hasselbalch equation. The combination of a high intramural PCO2 and mucosal acidosis may result from decreased splanchnic perfusion. The values of pHi and regional PCO2 (PrCO2) based on gastric tonometry reflect indirect index of visceral blood flow. In clinical practice the PCO2 of the gastric fluid is collected from saline sampled in the penetrable by carbon dioxide balloon. The silicon balloon is a part of tonometric probe placed in the gastric lumen. Device TONOCAP (Datex-Ohmeda, Helsinki, Finland) allows for full automatic measurement of the carbon dioxide regional pressure (PrCO2). Presented experimental and clinical studies confirmed the usefulness of gastric tonometry in visceral blood perfusion assessment during perioperative and critical ill stage. Finally, the technique allows to decrease the number of complications, treatment expenses and mortality.