title: Intra-Wound Antibiotics and Infection in Spine Fusion Surgery: A Report from Washington State's SCOAP-CERTAIN Collaborative.
abstract: BACKGROUND
  Surgical site infection (SSI) after spine surgery is classified as a "never event" by the Centers for Medicare and Medicaid. Intra-wound antibiotics (IWA) have been proposed to reduce the incidence of SSI, but robust evidence to support its use is lacking.
  
  
  METHODS
  Prospective cohort undergoing spine fusion at 20 Washington State hospitals (July 2011 to March 2014) participating in the Spine Surgical Care and Outcomes Assessment Program (Spine SCOAP) linked to a discharge tracking system. Patient, hospital, and operative factors associated with SSI and IWA use during index hospitalizations through 600 days were analyzed using a random effects logistic model (index), and a time-to-event analysis (follow-up) using Cox proportional hazards.
  
  
  RESULTS
  A total of 9,823 patients underwent cervical (47%) or lumbar (53%) procedures (mean age, 58; 54% female) with an SSI rate of 1.1% during index hospitalization. Those with SSI were older, more often had diabetes mellitus, and more frequently underwent lumbar (versus cervical) fusion compared with those without SSI (all p < 0.01). Unadjusted rates of SSI during index hospitalization were lower in patients who received IWA (0.8% versus 1.5%). After adjustment for patient, hospital, and operative factors, no benefit was observed in those receiving IWA (odds ratio [OR] 0.65, 95% confidence interval [CI]: 0.42-1.03). At 12 mo, unadjusted rates of SSI were 2.4% and 3.0% for those who did and did not receive antibiotics; after adjustment there was no significant difference (hazard ratio [HR] 0.94, 95% CI: 0.62-1.42).
  
  
  CONCLUSIONS
  Whereas unadjusted analyses indicate a nearly 50% reduction in index SSI using IWA, we did not observe a statistically significant difference after adjustment. Despite its size, this study is underpowered to detect small but potentially relevant improvements in rates of SSI. It remains to be determined if IWA should be promoted as a quality improvement intervention. Concerns related to bias in the use of IWA suggest the benefit of a randomized trial.
authors.affiliation: 1 Department of Surgery, University of Washington , Seattle, Washington.
authors.forename: Anne P
authors.initials: AP
authors.lastname: Ehlers
authors.affiliation: 2 Surgical Outcomes Research Center, University of Washington , Seattle, Washington.
authors.forename: Sara
authors.initials: S
authors.lastname: Khor
authors.affiliation: 3 Rainier Orthopedic Institute, Proliance Surgeons, Inc. , Puyallup, Washington.
authors.forename: Neal
authors.initials: N
authors.lastname: Shonnard
authors.affiliation: 4 Swedish Neuroscience Institute, Swedish Medical Center , Seattle, Washington.
authors.forename: Rod J
authors.initials: RJ
authors.lastname: Oskouian
authors.affiliation: 5 Department of Neurosurgery and Orthopaedics, Virginia Mason Medical Center , Seattle, Washington.|6 Department of Health Services, University of Washington , Seattle, Washington.
authors.forename: Rajiv K
authors.initials: RK
authors.lastname: Sethi
authors.affiliation: 7 Department of Orthopaedics and Sports Medicine, University of Washington , Seattle, Washington.
authors.forename: Amy M
authors.initials: AM
authors.lastname: Cizik
authors.affiliation: 8 Department of Orthopaedic Surgery, University of Chicago Medical Center , Chicago, Illinois.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Lee
authors.affiliation: 9 Department of Orthopaedic Surgery, University of California , Irvine, California.
authors.forename: Samuel
authors.initials: S
authors.lastname: Bederman
authors.affiliation: 10 Department of Orthopedics and Rehabilitation, University of Wisconsin , Madison, Wisconsin.
authors.forename: Paul A
authors.initials: PA
authors.lastname: Anderson
authors.affiliation: 1 Department of Surgery, University of Washington , Seattle, Washington.
authors.forename: E Patchen
authors.initials: EP
authors.lastname: Dellinger
authors.affiliation: 1 Department of Surgery, University of Washington , Seattle, Washington.
authors.forename: David R
authors.initials: DR
authors.lastname: Flum
mesh_terms: D000287:Administration, Topical; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D013122:Spinal Diseases / Q000601:surgery*; D013514:Surgical Procedures, Operative / Q000009:adverse effects*; D013530:Surgical Wound Infection / Q000453:epidemiology* / Q000517:prevention & control*; D016896:Treatment Outcome; D014861:Washington / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents
references.citation: J Clin Epidemiol. 2013 Aug;66(8 Suppl):S122-9
references.pmid: 23849146
references.citation: J Neurosurg Spine. 2013 Sep;19(3):331-5
references.pmid: 23848350
references.citation: Biomaterials. 2013 Apr;34(13):3174-83
references.pmid: 23391496
references.citation: Eur Spine J. 2012 Jun;21 Suppl 4:S476-82
references.pmid: 22160172
references.citation: J Bone Joint Surg Am. 2012 Feb 15;94(4):335-42
references.pmid: 22336972
references.citation: Am J Infect Control. 2009 Dec;37(10):783-805
references.pmid: 20004811
references.citation: N Engl J Med. 2009 Jun 4;360(23):2388-90
references.pmid: 19494212
references.citation: Am J Infect Control. 2009 Jun;37(5):387-97
references.pmid: 19398246
references.citation: BMC Musculoskelet Disord. 2006;7:53
references.pmid: 16787537
references.citation: Stat Med. 2005 May 30;24(10):1563-78
references.pmid: 15706581
references.citation: Am J Epidemiol. 1998 Apr 1;147(7):694-703
references.pmid: 9554609
references.citation: J Spinal Disord. 1997 Dec;10(6):482-7
references.pmid: 9438812
references.citation: Spine (Phila Pa 1976). 1997 Oct 15;22(20):2444-50; discussion 2450-1
references.pmid: 9355228
references.citation: Orthop Clin North Am. 1996 Jan;27(1):171-82
references.pmid: 8539047
references.citation: Orthop Clin North Am. 1996 Jan;27(1):47-52
references.pmid: 8539052
references.citation: World Neurosurg. 2015 May;83(5):816-23
references.pmid: 25535069
references.citation: Spine (Phila Pa 1976). 2015 Mar 1;40(5):332-41
references.pmid: 25901980
references.citation: Eur Spine J. 2015 Mar;24(3):533-42
references.pmid: 24838506
references.citation: Spine J. 2015 Feb 1;15(2):336-47
references.pmid: 25264181
references.citation: J Neurosurg Spine. 2014 Dec;21(6):974-83
references.pmid: 25259555
references.citation: Spine (Phila Pa 1976). 2013 Dec 1;38(25):2149-55
references.pmid: 24048091
references.citation: Spine J. 2013 Oct;13(10):1387-92
references.pmid: 23988461
references.citation: Eur J Orthop Surg Traumatol. 2013 Jul;23 Suppl 1:S35-40
references.pmid: 23744092