Assessment of the perfusion in peripheral tissue beds by subcutaneous oximetry and gastric intramucosal pH-metry in elective colorectal surgery.

Gastric intramucosal pH (pHi) and subcutaneous oxygen tension (PscO2) were compared with traditional perfusion parameters in patients undergoing elective colorectal surgery and were related to clinical outcome. Ten patients were studied per- and postoperatively and tissue oximetry studies were also performed in a group of 10 healthy volunteers. The response of PSCO2 to oxygen breathing proved to be the most sensitive predictor of clinical outcome. Of the 10 patients 8 failed to respond to an O2 challenge, while all 10 volunteers in the control group did so. Out of those 8 patients 6 presented with mainly infectious complications while only 3 had an inadequate perioperative urine output and none presented with signs of arterial or of gastric intramural acidosis. The present study suggests a possible relationship between clinical outcome and oxymetric signs of tissue hypoperfusion after O2 challenge in surgical patients, even in the presence of an adequate urine output and a normal gastric wall pH.