title: Surgical site infections among high-risk patients in clean-contaminated head and neck reconstructive surgery: concordance with preoperative oral flora.
abstract: BACKGROUND
  Salivary contamination of surgical wounds in clean-contaminated head and neck surgery with free flap reconstruction remains a major cause of infection and leads to significant morbidity. This study investigates the correlation between intraoral flora and surgical site infections (SSIs) among high-risk head and neck cancer patients undergoing resection and free flap reconstruction.
  
  
  METHODS
  One hundred twenty-nine patients were identified as being at high risk for infective complications based on cancer stage, tumor size, comorbid factors, and extent of reconstruction. All patients had intraoral swab cultures before surgery. Patients with culture-confirmed SSI after surgery were chosen for analysis, using the κ index and its 95% confidence interval for concordance analysis. All patients received clindamycin and gentamicin for antibiotic prophylaxis for 5 days. Antibiotic susceptibility testing of all isolates was obtained and analyzed.
  
  
  RESULTS
  Thirty-seven patients experienced SSI, or an infection rate of 28.3%, occurring at a mean of 9.3 postoperative days. The overall concordance between oral flora and SSI was fair to moderate (κ index of 0.25), but detailed analysis shows a higher concordance for known and opportunistic pathogens, such as Pseudomonas aeruginosa and Enterococcus faecalis, compared to typical oral commensals. Antibiotic susceptibility tests show rapid and significant increases in resistance to clindamycin, indicating a need for a more effective alternative.
  
  
  CONCLUSIONS
  Predicting pathogens in SSI using preoperative oral swabs did not demonstrate a good concordance in general for patients undergoing clean-contaminated head and neck surgery, although concordance for certain pathogenic species seem to be higher than for typical intraoral commensals. The rapid development of resistance to clindamycin precludes its use as a prophylactic agent.
authors.affiliation: From the *Department of Plastic and Reconstructive Surgery, Chang Gung Memorial Hospital-Kaohsiung Medical Center, Chang Gung University College of Medicine, Kaohsiung, Taiwan; †Department of Plastic, Reconstructive and Aesthetic Surgery, KK Women's and Children's Hospital, Singapore; and ‡Department of Surgery, University of Cincinnati College of Medicine, Cincinnati, OH.
authors.forename: Ching-Hsiang
authors.initials: CH
authors.lastname: Yang
authors.forename: Khong-Yik
authors.initials: KY
authors.lastname: Chew
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Solomkin
authors.forename: Pao-Yuan
authors.initials: PY
authors.lastname: Lin
authors.forename: Yuan-Cheng
authors.initials: YC
authors.lastname: Chiang
authors.forename: Yur-Ren
authors.initials: YR
authors.lastname: Kuo
mesh_terms: D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D019072:Antibiotic Prophylaxis; D002294:Carcinoma, Squamous Cell / Q000382:microbiology / Q000601:surgery; D002981:Clindamycin / Q000008:administration & dosage; D005260:Female; D058752:Free Tissue Flaps; D005839:Gentamicins / Q000008:administration & dosage; D006258:Head and Neck Neoplasms / Q000382:microbiology / Q000601:surgery*; D006801:Humans; D007012:Hypopharyngeal Neoplasms / Q000382:microbiology / Q000601:surgery; D008297:Male; D008875:Middle Aged; D009055:Mouth / Q000382:microbiology*; D057234:Preoperative Period; D019651:Plastic Surgery Procedures / Q000379:methods*; D018570:Risk Assessment; D012463:Saliva / Q000382:microbiology*; D000077195:Squamous Cell Carcinoma of Head and Neck; D013530:Surgical Wound Infection / Q000382:microbiology* / Q000517:prevention & control; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents; D005839:Gentamicins; D002981:Clindamycin