title: A pilot study of a triple antimicrobial-bonded Dacron graft for the prevention of aortic graft infection.
abstract: OBJECTIVE
  Perioperative infection of an aortic graft is one of the most devastating complications of vascular surgery, with a mortality rate of 10% to 30%. The rate of amputation of the lower limbs is generally >25%, depending on the graft material, the location of the graft and infection, and the bacterial virulence. In vitro studies suggest that an antibiotic-impregnated graft may help prevent perioperative graft infection. In a pilot animal study, we tested a locally developed technique of bonding Dacron aortic grafts with three antimicrobial agents to evaluate the ensuing synergistic preventive effect on direct perioperative bacterial contamination.
  
  
  METHODS
  We surgically implanted a 6-mm vascular knitted Dacron graft in the infrarenal abdominal aorta of six Sinclair miniature pigs. Two pigs received unbonded, uninoculated grafts; two received unbonded, inoculated grafts; and two received inoculated grafts that were bonded with chlorhexidine, rifampin, and minocycline. Before implantation, the two bonded grafts and the two unbonded grafts were immersed for 15 minutes in a 2-mL bacterial solution containing 1 to 2 × 10(7) colony-forming units (CFU)/mL of Staphylococcus aureus (ATCC 29213). Two weeks after graft implantation, the pigs were euthanized, and the grafts were surgically excised for clinical, microbiologic, and histopathologic study.
  
  
  RESULTS
  The two bonded grafts treated with S aureus showed no bacterial growth upon explant, whereas the two unbonded grafts treated with S aureus had high bacterial counts (6.25 × 10(6) and 1.38 × 10(7) CFU/graft). The two control grafts (unbonded and untreated) showed bacterial growth (1.8 × 10(3) and 7.27 × 10(3) CFU/graft) that presumably reflected direct, accidental perioperative bacterial contamination; S cohnii ssp urealyticus and S chromogenes, but not S aureus, were isolated. The histopathologic and clinical data confirmed the microbiologic findings. Only pigs that received unbonded grafts showed histopathologic evidence of a perigraft abscess.
  
  
  CONCLUSIONS
  Our results suggest that bonding aortic grafts with this triple antimicrobial combination is a promising method of reducing graft infection resulting from direct postoperative bacterial contamination for at least 2 weeks. Further studies are needed to explore the ability of this novel graft to combat one of the most feared complications in vascular surgery.
authors.affiliation: Texas Heart Institute at St. Luke's Episcopal Hospital, Houston, Tex 77030, USA. iaboshady@heart.thi.tmc
authors.forename: Ibrahim
authors.initials: I
authors.lastname: Aboshady
authors.forename: Issam
authors.initials: I
authors.lastname: Raad
authors.forename: Aamir S
authors.initials: AS
authors.lastname: Shah
authors.forename: Deborah
authors.initials: D
authors.lastname: Vela
authors.forename: Tanya
authors.initials: T
authors.lastname: Dvorak
authors.forename: Hazim J
authors.initials: HJ
authors.lastname: Safi
authors.forename: L Maximilian
authors.initials: LM
authors.lastname: Buja
authors.forename: Kamal G
authors.initials: KG
authors.lastname: Khalil
mesh_terms: D000818:Animals; D000890:Anti-Infective Agents / Q000008:administration & dosage*; D001012:Aorta, Abdominal / Q000382:microbiology / Q000473:pathology / Q000601:surgery*; D001807:Blood Vessel Prosthesis; D019917:Blood Vessel Prosthesis Implantation / Q000009:adverse effects / Q000295:instrumentation*; D002710:Chlorhexidine / Q000008:administration & dosage; D020099:Coated Materials, Biocompatible; D004195:Disease Models, Animal; D004359:Drug Therapy, Combination; D008911:Minocycline / Q000008:administration & dosage; D010865:Pilot Projects; D011093:Polyethylene Terephthalates; D011474:Prosthesis Design; D016459:Prosthesis-Related Infections / Q000382:microbiology / Q000473:pathology / Q000517:prevention & control*; D012293:Rifampin / Q000008:administration & dosage; D013203:Staphylococcal Infections / Q000382:microbiology / Q000473:pathology / Q000517:prevention & control*; D013552:Swine; D013556:Swine, Miniature; D013997:Time Factors
chemical_list: D000890:Anti-Infective Agents; D020099:Coated Materials, Biocompatible; D011093:Polyethylene Terephthalates; D008911:Minocycline; D002710:Chlorhexidine; D012293:Rifampin