Establishment of reference pressure of transcutaneous oxygen for the comparative evaluation of problem wounds

Seventy-two healthy males and females serially breathed air and 100% O2 at 1.0 atm abs (1.01 bar; AIR and O2, respectively), then 100% O2 at 2.36 atm abs (2.39 bar, HBO) to establish reference values for chest (CH), leg (LG), and foot (FT) PtcO2. Subjects sequentially a) rested supine with legs extended (baseline); b) elevated their monitored leg; c) returned to supine/extended position; d) assumed a seated, both legs dependent posture; and e) returned to supine/extended position. LG and FT PtcO2 decreased during leg elevation and increased when both legs were dependent during AIR, O2, and HBO (P < 0.0001, respectively). LG PtcO2 of females exceeded that for males in all conditions (P < 0.05 to P < 0.0001). Baseline CH PtcO2 also was greater than LG PtcO2 for all subjects in all conditions (P < 0.01 to P < 0.0001) and greater than FT PtcO2 for all conditions (P < 0.01 to P < 0.0001) except AIR. We conclude that: a) position and hyperoxygenation of an extremity significantly affect PtcO2; b) PtcO2 does not follow a decreasing CH to FT gradient in all conditions; c) a gender difference exists for LG PtcO2; and d) PtcO2 reference data are established for the comparative evaluation and clinical management of problem wounds.