Tissue oxygen and carbon dioxide tensions in healing rabbit tibias

Tissue gas tensions were measured in healing rabbit tibias by means of an implanted Silastic tonometer. During the course of the healing, tissue oxygen tensions increased progressively and carbon dioxide tensions underwent a gradual decline. In all phases of repair, bone tissue gases responded to systemic hyperoxia and hypercarbia. Occlusion of local circulation resulted in tissue anoxia and accumulation of carbon dioxide. Acetazolamide, an inhibitor of carbonic anhydrase, elevated the carbon dioxide tension in the bone but not in the blood which supports earlier data indicating the presence of a functional carbonic anhydrase system in actively metabolizing bone tissue.