The effect of local application of vancomycin powder after posterior lumbar interbody fusion surgery on prevention of surgical site infection and fusion rate

English Keywords:Lumbar spine surgery  Vancomycin  Topical administration  Surgical site infection  Fusion

English Abstract:

  【Abstract】 Objectives: To assess the effect of local application of vancomycin powder after posterior lumbar interbody fusion surgery on prevention of surgical site infection(SSI) and fusion rate. Methods: From January 2013 to December 2014, 569 cases undergoing posterior lumbar interbody fusion surgery in PLA General Hospital were analyzed retrospectively. Exclusion criteria included mimimally invasive surgeries without implants, spinal deformity surgeries refered to thoracolumbar vertebrae, previous history of infections in three months before hospitalization, patients allergic to vancomycin or cephalosporin antibiotics, patients with a postoperative follow-up of less than 12 months, lack of postoperative X-ray and computed tomography(CT) examination. Patinents receiving the routine scheme for preventing SSI were assigned into non-vanco group(group A, n=363). There were 195 males and 168 females; the average age was 51.5±19.4 years, with 162 cases ≥55 years and 201 cases ＜55 years; the average BMI was 28.1±6.7kg/m2; there were 80 smokers and 283 non-smokers. Patients in group B received the routine scheme and local application of vancomycin powder 1g(n=206). There were 98 males and 108 females; the average age was 53.7±18.6 years, with 99 cases ≥55 years and 107 cases ＜55 years; the average BMI was 30.2±7.1kg/m2; there were 37 smokers and 169 non-smokers. There was no statistical difference in sex, age, BMI, smoking, comorbidities(diabetes, hypertension, cardiovasculardisease, respiratory disease), history of lumbar surgery, operation time, blood loss, hemovac drain usage, hemovac drain time, volume of drainage, number of levels instrumented or number of days hospitalization between the two groups(P＞0.05). The situations of SSI and fusion were compared between the two groups. Results: Total SSI decreased to 8 cases(3.88%) in vanco group(group B) compared with 30 cases(8.26%) in non-vanco group(P=0.044). Staphylococcal infection presented in 4 patients(1.94%) with deep methicillin-resistant staphylococcus aureus(MRSA) infection in 1 patient(0.49%) in group B, which decreased statistically significantly compared with 20 patients(5.51%) and 13 patients(3.58%) in group A(P＜0.05). There was no statistically significant difference in non-staphylococcal infection between 4 patients(1.94%) in group B and 10 patients(2.75%) in group A(P=0.547). There was no significant difference in fusion rate between the two groups at 12 months postoperatively(P＞0.05). No complications such as renal toxicity and ototoxicity were observed in vanco group. Conclusions: SSI rate decreases significantly through the local application of intrawound vancomycin powder after posterior lumbar interbody fusion surgery. Meantime, no effect on fusion rate is observed.