rifampin and indium-oxine

Every effort to reduce synthetic graft infection is welcome and when designing antibiotic-bonded grafts it is important not to increase graft thrombogenicity. In order to study the acute thrombogenicity of rifampicin-soaked gelatin-sealed Dacron grafts compared with untreated gelatin-sealed Dacron grafts, an experimental carotid artery sheep model was used. Twenty sheep were anaesthetised and 7-cm-long 5-mm-wide externally supported gelatin-sealed knitted Dacron grafts were sutured end to end into each carotid artery after excising a portion of that vessel. Test grafts had previously been immersed for 15 min in a rifampicin solution (1 mg ml-1) while control grafts were immersed in physiological saline for 15 min. There were two groups with 10 sheep in each. In one group the blood flow through the grafts was unrestricted but in the second the flow was restricted to 25 ml min-1. Platelets from sheep labelled with 111In and sheep fibrinogen labelled with 125I were injected intravenously. The isotope activities were continuously measured proximally and distally over the grafts for 4 h. With unrestricted flow 4 out of 10 rifampicin-soaked grafts occluded compared with 2 out of 10 control grafts (N.S.). Time to occlusion, thrombus weight, platelet and fibrinogen activity did not differ. In the restricted flow group 9 out of 10 rifampicin-soaked grafts occluded compared with 6 out of 10 control grafts (N.S.). The time to occlusion did not differ. The thrombus weight in the rifampicin group was significantly higher compared with the control group.(ABSTRACT TRUNCATED AT 250 WORDS)

Topics: Animals; Blood Flow Velocity; Blood Vessel Prosthesis; Carotid Arteries; Female; Fibrinogen; Gelatin; Graft Occlusion, Vascular; Indium Radioisotopes; Iodine Radioisotopes; Male; Organometallic Compounds; Oxyquinoline; Platelet Adhesiveness; Polyethylene Terephthalates; Radionuclide Imaging; Rifampin