177 So the Bone Flap Hit the Floor, Now What?

Abstract

INTRODUCTION: Dropping the free bone flap on the operating room floor during a neurosurgical procedure is a rare and poorly documented accident. In fact, it has been reported in up to 3 out of 1000 operations involving craniotomies. The literature guiding its management is insufficient: to date, there is no protocol for sterilization of an accidentally contaminated flap in order to reposition it safely on the patient's skull. METHODS: Cadaveric human bone flaps were collected and intentionally dropped onto the floor of a neurosurgical operating room. Bacterial contamination from these flaps was quantified in colony forming units (CFU) counted on culture plates inoculated with the fragments. Identified species were included in a mixed preparation of microorganisms used to artificially contaminate fragments from 29 other individual flaps in a standardized manner. All 29 contaminated flaps were previously cut into five pieces and the following five sterilization protocols were completed on a fragment per flap each: rinsing with saline, mechanical debridement with sterile gauze, rinsing with antibiotics, rinsing with alcoholic chlorhexidine and flash sterilization by autoclave. Decontamination was measured by inoculation onto culture plates and CFU count. RESULTS: The observed contamination from a flap dropped on an operating room floor can be significant (up to 120 CFU cultured per flap). All protocols tested decreased bacterial load of the bone flaps to different degrees: saline by 95.7%, mechanical debridement by 97.6%, antibiotic bath by 99.5%, alcoholic chlorhexidine by 99.9% and flash sterilization by 100.0%. CONCLUSIONS: In the event of the accidental fall of a bone flap, decontamination by rinsing in an alcohol-chlorhexidine solution, which seems to represent the best combination of effectiveness versus the risks and the complexity of the method, could be considered.