Clinical and microcirculatory effects of transcutaneous CO2 therapy in intermittent claudication. Randomized double-blind clinical trial with a parallel design

Background: This randomized, double blind trial determined the short and long-term clinical and hemodynamic vasodilator effects induced by percutaneous applications of natural CO2 gas in patients with moderate Fontaine stage II. Patients and methods: 62 patients with intermittent claudication (100-500 meters) were randomized to 18 consecutive days of CO2 treatment or placebo (air). The gas fluids were applied at a constant temperature of 30°C on pre-humidified skin. The effects of the treatment were evaluated by total distance walked (primary criterion) and hemodynamic and microcirculatory findings. Patients also answered a quality of life questionnaire. Results: The Strandness test showed a significant increase in total distance walked (+ 131 meters, 66%; p = 0.001) and pain-free distance (+ 81 meters, 73%; p = 0.02) after 18 days of CO2 treatment. The improvement was maintained 3 and 12 months later. The systolic pressure index (ABI) increased by 37% (p = 0.001) 1 minute after treadmill walking and ABI ...