Transcutaneous oxygen tensions in assessing the treatment of healed venous ulcers

Transcutaneous oxygen tension (Ptc,O2) was assessed as an indicator of risk of reulceration in 68 limbs with healed venous ulcers. Ptc,O2 was also used to assess two methods of ulcer prophylaxis. Measurements were made over the gaiter skin, the healed ulcer and the upper arm. The results were expressed as a ratio of the lower limb readings over those taken from the arm. Patients were randomized, after the ulcer had healed, to elastic stockings and stanozolol, or elastic stockings and surgical ligation of incompetent superficial veins. Patients who declined to participate in the study were prescribed elastic stockings only. Those limbs remaining healed at 12 months had Ptc,O2 ratios remeasured. The Ptc,O2 ratios from limbs that reulcerated were not significantly lower than those from limbs remaining healed. The Ptc,O2 ratio was significantly increased in limbs treated by stanozolol and elastic stockings (P less than 0.05) and by surgery and elastic stockings (P less than 0.05). There was no significant increase in Ptc,O2 in limbs treated by elastic stockings alone. In those treated by surgery and elastic stockings, there was a significant improvement in limbs with normal deep veins (P less than 0.01), but not in limbs with post-thrombotic changes on ascending phlebography. Although these two methods of ulcer prophylaxis improve the Ptc,O2 ratio, a high ratio has not been shown to be beneficial in preventing ulcer recurrence.