Use of transcutaneous O2 monitoring in the intraoperative management of severe peripheral vascular disease.

Transcutaneous O2 (PtcO2) and CO2 (PtcCO2) monitoring has been used in infants, in critically ill adults, and more recently, in peripheral vascular disease. The present report compares values of centrally placed chest (PtcO2 and PtcCO2) sensors with values of peripherally placed calf (Ptc'O2 and Ptc'CO2) sensors in a patient with severe peripheral vascular disease during performance of an axillofemoral bypass graft. The calf Ptc'O2 values may be expressed as a ratio of their corresponding PaO2 values or as a percentage of the chest PtcO2, i.e., calf Ptc'O2/chest PtcO2 X 100. The ratio reflects local tissue perfusion in the face of fluctuating PaO2 and central PtcO2 values. The data demonstrate that PtcO2 sensors reflect tissue blood flow and oxygenation and, therefore, are useful measures of tissue perfusion, especially during limb revascularization.