Therapy with hyperbaric oxygen for experimental osteomyelitis due to Staphylococcus aureus in rabbits.

Hyperbaric oxygen (HBO) is used as adjunctive therapy of chronic osteomyelitis, but its efficacy remains controversial. A recently developed rabbit model for osteomyelitis due to Staphylococcus aureus was used to compare the results of treatment with HBO, cephalothin, a combination of both, or no treatment. Cultures of bone were positive in 10 (91%) of 11 control animals (untreated), five (36%) of 14 animals treated with HBO, eight (47%) of 17 treated with cephalothin, and six (40%) of 15 treated with HBO plus cephalothin. All three treatment groups differed significantly from untreated controls in the number of positive cultures obtained (P less than 0.01), but there were no significant differences among treatment groups. In vitro growth and killing curves (1.0 microgram of cephalothin/ml) constructed after exposure to HBO revealed no change from parallel control studies in ambient air. These data demonstrate that therapy with HBO is at least as effective as antibiotic therapy. The therapeutic effectiveness of HBO does not appear to be related to antibacterial activity.