Toxic Effects of Wound Irrigation Solutions on Cultured Tibiae and Osteoblasts

Irrigating wounds with solutions of antiseptic or antibiotic agents is routinely performed in orthopaedic surgery to reduce the incidence of microbial infection. The effects of these agents on healthy bone tissue is unknown. Three commonly employed antiseptic agents (hydrogen peroxide, Betadine solution, Betadine scrub) and one antibiotic solution (bacitracin) were tested on tibiae and osteoblasts isolated from embryonic chicks. Osteoblast function was evaluated by glycolytic energy metabolism (lactate production), cell number (DNA content), and collagen synthesis ([H]proline hydroxylation). Two series of experiments were performed. To study concentration-related effects, tibiae or cells were exposed to a range of concentrations of the agents (diluted in saline, 0.9% NaCl) for 2 min, rinsed with saline, and incubated for 24 h in medium containing [H]proline. For the recovery study, the cells were exposed to an effective, but nonlethal, concentration of the antiseptic agents for 2 min, rinsed with saline, and the incubation was continued in complete culture medium for 6, 12, 24, 48, or 72 h with [H]proline added for the final 6 h. Solutions containing the antiseptic agents were cytotoxic to both bones and cells at concentrations well below those used clinically in irrigation solutions. In contrast, bacitracin at the concentrations tested was safe for osteoblasts and tibiae. These results suggest that the use of irrigation solutions containing H2O2, Betadine solution, or Betadine scrub on exposed bone tissue should be considered with caution