Time-Dependent Effects of Chlorhexidine Soaks on Grossly Contaminated Bone
Journal of Orthopaedic Trauma
Objective: The purpose of this study was to quantify the reduction in the bacterial burden of grossly contaminated bone segments using different chlorhexidine (CHL) solutions. We hypothesized that 4% CHL would be the most efficient decontaminate. Methods: Fifty four bone segments were harvested from fresh frozen porcine legs. Each specimen was dropped onto a Mueller Hinton medium that was inoculated with Staphylococcus aureus (lux). These genetically engineered bacteria emit photons in propor
... photons in propor tion to their number, allowing for quantification. The segments were retrieved after 5 seconds of exposure. Baseline imaging provided the initial bacterial load. An equal number of specimens were soaked in normal saline (NS), 2%CHL, or 4%CHL. Specimen reimaging was completed at the 5 , 10 , 20 , 30 , and 60 minute marks. Results: The average bacterial count on the bone segments were 2.18 · 10 7 for NS, 2.31 · 10 7 for 2%CHL, and 2.00 · 10 7 for 4%CHL. The percent reduction in bacterial counts at the 5 , 10 , 20 , 30 , and 60 minute marks were NS: 0%, 0%, 0%, 29.84%, 72.23%; 2%CHL: 93.09%, 98.16%, 99.21%, 99.63%, 99.81%; 4%CHL: 94.32%, 97.60%, 99.25%, 99.63%, 99.82%. At all time intervals, there was a significant difference between the 2%CHL and 4%CHL groups compared with the NS group (P , 0.0001) and no difference between the 2%CHL and 4%CHL groups. Conclusions: This study provides new data supporting the use of CHL to decontaminate grossly soiled bone segments. To maximize efficiency and decrease potential untoward effects, the authors recom mend 20 minute soaks using 2% CHL for contaminated bone segments. (J Orthop Trauma 2012;26:574 578) Reprints: Public reporting burden for the collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing this burden, to Washington Headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington VA 22202-4302 Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to a penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number FIGURE 3. Average percentage of bacteria remaining on bone segments for each solution.