OBJECTIVES: : To evaluate the impact of re-usable surgical instruments management on the cost of performing Total Knee Arthroplasty (TKA) at a Japanese general hospital, in terms of time, personnel and financial resources.

METHODS: : A detailed process map was developed for the re-usable surgical instruments management cycle at our study site, from the time surgery was scheduled until instruments were used in the Operating Theatre (OT), to post-operative return to storage. The prospective study (conducted 1/7/2017-30/9/2017) included time-in-motion direct observations of 15 TKAs, supplemented by literature and 21 interviews with hospital staff. Time-Driven Activity Based Costing (TDABC) methodology was used to identify who performed each step, its duration, and associated costs. Personnel costs for each phase of instrument management were measured based on job category labour rates.

RESULTS: : To support a 117 minute surgery, instruments were processed over a 6 day span behind the scenes, taking a total of 1,129 minutes from scheduling each TKA to return of instruments to storage. The hospital required at least 6 types of staff to manage re-usable surgical instruments: doctors, OT nurses, scrub nurses, central supply nurse assistants, medical office assistants, and medical engineers. This labour cost amounted to ¥65,027, which was nearly on par with mobilizing the entire surgical team for the TKA procedure (¥80,792). Hospital cost was split across pre-surgery (18%), surgery (73%), and post-surgery (9%).

CONCLUSIONS: : The surgical instruments management process and their influence on the overall cost of the TKA procedure has been brought to light for the first time in Japan. This exploratory study has identified important opportunities for the hospital to improve efficiency, especially for this relatively complex process requiring a high burden of support activities from skilled hospital staff.