Risk factors for deep infection in the surgical site after spinal operations

Introduction Despite significant steps in prevention and treatment of infectious complications after surgical treatment on the spine, many issues remain unsolved. There is a sufficient number of scientific reports on the treatment of postoperative infection, however, only a few studies present multivariate analysis of risk factors of developing deep infection after surgical intervention. In the domestic literature, such reports are rare. According to most sources, the rate of infection after spinal interventions ranges from 0.7 to 11.9 %. Material and methods We conducted a retrospective multivariate analysis of the data collected to determine the risk factors of deep surgical infection after spinal surgery at various levels and volumes. To fully determine the risk factors, not only surgical factors were evaluated, but also individual characteristics of patients contributing to the increase in infection rates. The purpose of this study was to compare patients who developed local deep infection after spine surgery, with a randomly selected group of patients who did not develop this complication, to identify modifiable risk factors. Results In the period from 2005 to 2016, we identified 79 cases of postoperative deep infection. The overall morbidity rate after 5564 operations (in 5328 patients) was 1.48 %. The most common causative agent of the infectious process was S. epidermidis MRSE. All patients underwent at least one revision intervention, with additional antibiotic therapy course. To reduce the number of infectious complications in patients at risk, preventive measures were carried out, including changes in the volume and type of surgery, prolonged administration of antibacterial drugs, etc. Of the surgical risk factors, the greatest differences between the groups were noted in the types of surgical interventions, implementation of spondylodesis, and previously performed operations on the spine. Also, the risk of purulent-septic complications increased in high BMI, diabetes and urinary tract infection. Conclusion The conducted multivariate analysis reliably confirms the significance of the risk factors identified.