An infection-resistant PTFE vascular graft; spiral coiling of the graft with ofloxacin-bonded PTFE thread.
OBJECTIVE
To develop an infection-resistant polytetrafluoroethylene (PTFE) vascular graft for potential clinical use in grafting in sites of bacterial contamination and in replacement of the infected grafts.


METHODS
Experimental study in rabbits.


METHODS
An antibiotic ofloxacin (OFLX) was bonded to a sheet of PTFE by impregnation, which was cut and twisted into fine threads. The in-vitro antibacterial activity of OFLX-PTFE thread was determined by measuring the zone of growth inhibition against Escherichia coli. The thread was spirally coiled around a ridged outerwall PTFE to make the OFLX-PTFE graft. OFLX-PTFE graft or control graft was interposed in the inferior vena cava (IVC) of rabbits and the entire graft was covered with fibrin containing a fixed number of E. coli. Three or 7 days after the grafting, the grafts with perigraft tissue were harvested and subjected to bacteriological studies.


RESULTS
In spite of early phase rapid elution of OFLX, a significant antibacterial activity was retained for more than 2 weeks. The antibacterial activity of OFLX-PTFE threads implanted in the subcutaneous space of rabbits decreased to 48% after 24 h and to approximately 1% after a week. The swab culture of all the control grafts was positive, while only one of 13 PTFE-OFLX grafts was positive. The number of viable bacteria in the perigraft tissue of OFLX-PTFE grafts was remarkably low in comparison with that of control grafts. Thus, the OFLX-PTFE grafts exhibited a marked in-vivo antibacterial activity.


CONCLUSIONS
By a unique method, it was possible to furnish PTFE graft with an excellent infection-resistant property, without affecting the original biological behaviour.
Okahara
K
K
Department of Surgery II, Osaka University Medical School, Japan.
Kambayashi
J
J
Shibuya
T
T
Kawasaki
T
T
Sakon
M
M
Dohi
Y
Y
Oka
Y
Y
Ito
S
S
Miyake
S
S
D000818:Animals; D001807:Blood Vessel Prosthesis / Q000382:microbiology*; D004926:Escherichia coli / Q000254:growth & development; D008826:Microbial Sensitivity Tests; D015242:Ofloxacin / Q000008:administration & dosage; D011138:Polytetrafluoroethylene; D016459:Prosthesis-Related Infections / Q000517:prevention & control; D011817:Rabbits; D013242:Sterilization
D011138:Polytetrafluoroethylene; D015242:Ofloxacin