title: Bacterial wound contamination during simple and complex spinal procedures. A prospective clinical study.
abstract: BACKGROUND
  Spinal procedures have a potential of intraoperative contamination. C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) have been used to diagnose postoperative infections after spinal surgery. However, it has not been demonstrated if there is an association between surgical site contamination and clinical manifestation of postoperative infection based on inflammatory markers and patients' clinical course.
  
  
  OBJECTIVE
  The purpose of this prospective study was to evaluate the association between surgical site contamination and the development of a postoperative infection in simple and complex surgical procedures. C-reactive protein and ESR levels were observed. The correlation between their values, surgical time, type of surgical procedures, and contaminated surgical sites was investigated.
  
  
  METHODS
  Prospective clinical study.
  
  
  METHODS
  The study consisted of 40 patients divided into two groups. Group A included 20 patients (mean age, 46.2 years; 12 women and 8 men) who underwent an open discectomy for a lumbar herniated disc. Group B consisted of 20 patients (mean age, 67.9 years; 11 women and 9 men) who underwent a decompression and instrumented fusion for lumbar spinal stenosis. They were followed up for an average of 26.7 months (range, 11-40 months).
  
  
  METHODS
  Samples were obtained for cultures in standard time intervals during surgery. The types of bacteria cultured were evaluated, and CRP and ESR levels were measured.
  
  
  METHODS
  Simple lumbar discectomy (Group A, 20 patients) and instrumented lumbar decompression for degenerative lumbar stenosis (Group B, 20 patients) were performed in a prospective consecutive series of patients. All patients were operated by the same surgeon in the same operating room. Surgical site preparation in each patient was done by a standard manner. Samples were obtained for cultures in standard time intervals during surgery. C-reactive protein and ESR levels were measured preoperatively on the 3rd, 7th, and 21st postoperative days, and the clinical course of each patient was recorded.
  
  
  RESULTS
  From 40 patients, three patients in Group A and five patients in Group B, a total of eight patients (20%) had positive cultures for bacteria. There was no statistical significance between contamination and duration of surgery in both groups. None of the patients with positive intraoperative cultures developed any clinical signs of superficial or deep postoperative spinal infection, and no additional antibiotic treatment was administered. Three patients with negative cultures developed a postoperative infection. There were no differences in CRP and ESR values between patients with contamination and noncontamination in both groups. C-reactive protein and ESR levels were significantly elevated in complex procedures (Group B) than in simple procedures (Group A). Statistical analysis of CRP and ESR values in both groups and types of bacteria cultured intraoperatively are presented.
  
  
  CONCLUSIONS
  The results of this study demonstrate that intraoperative contamination can occur during simple and complex spinal procedures. In the absence of postoperative signs of infection in patients with intraoperative contamination, there is no need of continuing antibiotic treatment. Postoperative kinetics of CRP and ESR showed to be the same in patients with and without intraoperative contamination. Higher levels of inflammatory markers were noted in complex spinal procedures where instrumentation was applied.
authors: Department of Orthopaedics, University of Ioannina, School of Medicine, 11 Pantazidi St, Ioannina 45221, Greece. idgelalis@gmail.com
authors: Ioannis D
authors: ID
authors: Gelalis
authors: Christina M
authors: CM
authors: Arnaoutoglou
authors: Angelos N
authors: AN
authors: Politis
authors: Nikolaos A
authors: NA
authors: Batzaleksis
authors: Pavlos G
authors: PG
authors: Katonis
authors: Theodore A
authors: TA
authors: Xenakis
mesh_terms: D000328:Adult; D000368:Aged; D001424:Bacterial Infections / Q000097:blood / Q000453:epidemiology* / Q000209:etiology; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000032:analysis; D019299:Decompression, Surgical / Q000009:adverse effects*; D017586:Diskectomy / Q000009:adverse effects*; D005260:Female; D006801:Humans; D007405:Intervertebral Disc Displacement / Q000601:surgery; D008159:Lumbar Vertebrae; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013123:Spinal Fusion / Q000009:adverse effects*; D013130:Spinal Stenosis / Q000601:surgery; D013530:Surgical Wound Infection / Q000097:blood / Q000453:epidemiology*
chemical_list: D002097:C-Reactive Protein