Intraoperative risk factors for surgical site infection in posterior cervical surgery

English Keywords:Posterior cervical surgery  Surgical site infection  Risk factor

English Abstract:

  【Abstract】 Objectives: To investigate the intraoperative risk factors for surgical site infection(SSI) in posterior cervical surgery. Methods: A retrospective case-control study of patients following posterior cervical surgery was performed from January 2007 to December 2016. Diagnosis of patients included cervical spondylotic myelopathy, cervical trauma and ossification of posterior longitudinal ligament. Then patients developing deep SSI was compared with a randomly selected group of patients without deep SSI, in order to identify changable risk factors. The clinical data were recorded including gender, age, preoperative mJOA, diagnosis, surgery types, medical co-morbidity, body mass index, smoking, blood transfusion, number of surgical levels, duration of surgery, blood loss and number of drainage tubes. According to the univariate analysis, the significant factors were analyzed with the multifactor Logistic regression analysis. The receiver operating characteristic curve was conducted to identify the optimal cut-off point for the significant factors. Results: 13 cases were identified with deep SSI(CDC criteria) in the study and the overall rate of spinal surgical site infection was 0.35%(13 of 3720) during the ten years. Surgery employed in the study included unilateral open-door lamnioplasty, unilateral open-door lamnioplasty + lateral mass screw fixation and resection of spinal canal posterior wall + lateral mass screw fixation. The 13 cases included 3 females and 10 males with an average age of 58.38±2.52 years. According to the univariate analysis, smoking, number of surgical levels, duration of surgery, blood loss and number of drainage tubes were included for multivariate analysis. The multivariatelogistic regression identified blood loss and duration of surgery as the independent risk factors for SSI, while the optimal cut-off point for blood loss and duration of surgery were 180ml and 84.5min. Conclusions: Blood loss and duration of surgery are identified as the independent risk factors of SSI in posterior cervical operation.