Assessment of perfusion in postoperative patients using tissue oxygen measurements.

Subcutaneous tissue oxygen tension was measured as an index of perfusion in 44 postoperative patients. Hypoperfusion was defined as suboptimal tissue oxygen tension unresponsive to increased inspired oxygen but becoming responsive after increased fluid infusion. Twelve of thirty patients who underwent major abdominal and flank operations were found to be suboptimally perfused by this definition despite adequate fluid maintenance according to standard clinical criteria including urine output. Apparently, a significant number of postoperative abdominal surgery patients are not optimally perfused, and this state is not recognized by the present clinical criteria. Tissue oximetry may be a useful objective method of assessing tissue perfusion.