Evaluation of catheter thrombogenicity in vivo with indium-labeled platelets

Platelets labeled with a lipid-soluble indium-111 8-hydroxyquinoline (oxine) complex were evaluated as an agent to measure the rate and degree of in vivo platelet accumulation on catheters. Polyethylene catheters and Teflon-coated guidewires were inserted into the femoral arteries or veins of dogs that had been injected with indium-labeled platelets. The catheters were passed to either the abdominal aorta or inferior vena cava and left in situ for 30 minutes to three hours. Images were obtained every five minutes with a gamma camera. This labeling technique is reproducible, allows multiple testing with a single preparation, and is relatively noninvasive. The results are easily quantitated to allow testing of different materials and coatings.