Carbon dioxide infusion is a non surgical procedure applied via percutaneous, transdermal and subcutaneous. Increase in the concentration of carbon dioxide decreases pH activating local nitric oxide that stimulates collateral vessels formation, vascular endothelial growth factor and basic fibroblast growth factor. Carbon dioxide infusion restores the blood flow in chronic wounds of the lower limbs.

Ten patients with chronic wounds caused by venous insufficiency at both lower limbs were distributed into groups. Group I was composed by wounds in the right lower limb that received carbon dioxide and group II by wounds in the left lower limb that not received carbon dioxide, both related to the same patient. Carbon dioxide infusion was performed with the needle pointed toward the granulation tissue, 5cm distant from each one at intervals of 4 days. Biopsies were collected from the wounds before carbon dioxide infusion and after the 3rd, 5th and 10th application. Statistical analysis of the data was performed using Wilcoxon's test and Friedman's variance analysis and multiple comparisons test.

Inclusion Criteria:

• chronic wounds caused by venous insufficiency

Exclusion Criteria:

• other diseases of the lower limbs

10 patients with chronic wounds on both lower limbs