Abstract
Introduction : The rate of surgical site infections (SSI) after spinal surgery is thought to be low. However, once this complication occurs, especially in instrumentation surgery, we require prolonged antibiotic therapy and repeated operations, such as wound debridement or removal of the instruments. In this paper, we investigate SSI occurring at Suita Municipal Hospital and Iseikai Hospital between January 2012 and December 2015 as well as the risk factors in each hospital using the Japan Nosocomial Infections Surveillance (JANIS) data.
Materials and methods : We experienced 753 cases of spinal surgery, including 482 cases of decompression with laminectomy (abbreviated as LAM in JANIS [Group L]) and 271 cases of spinal fusion with instrumentation (abbreviated as FUSN in JANIS [Group F]) for 4 years from 2012 to 2015. For baseline data, we compared the JANIS data released in the period containing 19,162 cases in Group L and 17,440 cases in Group F.
Results : Among the 753 cases, SSI occurred in 11 (1.4%) ; 3 cases (0.6%) in Group L and 8 cases (3.0%) in Group F. Compared to the JANIS data, the rate of SSI was identical in Group L (1.3%) but higher in Group F (1.9%). In our SSI cases, there were several factors affecting infection ; diabetes mellitus in 3 cases, immunosuppressive states in 5, severe atopic dermatitis in 2, and re-operation in 2. The risk index (RI) used in JANIS was RI : 0 in 2 cases and RI : 1 in 1 case in the 3 SSI cases of Group L, while it was RI : 1 in 6 cases and RI : 2 in 2 cases in the 8 SSI cases of Group F. The most important factor was found to be the long operation time ; 6 cases of 8 SSI cases in Group F exceeded 260 minutes, which is the time 75% of operations that registered in JANIS required to complete. As a result of the comparative analysis, we implemented a new protocols when we had to operate for long time period, which resulted in the suppression of postoperative infection.
Conclusion : We investigated the risk factors of SSI cases in spine surgery by using JANIS data. We made effective measures to longer operation time which was thought to be the most affected factors in our hospitals.
