IN-VIVO EVALUATION OF A NEW-TYPE-I COLLAGEN HEMOSTATIC PLUG FOR HIGH-RISK, LARGE-CORE BIOPSIES

PURPOSE: To evaluate in a swine model the hemostatic properties of a n ew, expansile type I collagen plug for use in high-risk renal biopsies . MATERIALS AND METHODS: Highly purified bovine type I collagen was fo rmed into porous cylindrical plugs and compressed radially to fit into a 5-F delivery system. On hydration these collagen plugs demonstrated radial expansion with approximately 1,600% volumetric expansion ratio . Direct exposure of both kidneys was performed in a 25-kg swine, and a bolus of 3,000 U of heparin was administered to create a coagulopath ic state. A 14-gauge Temno coaxial biopsy gun was utilized in performi ng nine pairs of renal biopsies. The first biopsy of each biopsy pair represented the control biopsy (without collagen plug placement), wher eas the second biopsy of each pair represented the plugged biopsy. The presence and duration of hemorrhage from each biopsy site was monitor ed visually.RESULTS: The biopsy sites without collagen plug showed imm ediate hemorrhage in nine of nine cases (100%), and in two of nine cas es (22%) pulsatile bleeding was noted. With the use of the collagen pl ug, seven of nine (78%) sites showed immediate hemorrhage, but in no c ase was pulsatile bleeding noted. Mean bleeding duration was 156 secon ds for the control biopsies versus 73 seconds for the biopsy sites plu gged with collagen (P = .03, Mann-Whitney rank sum test). Bleeding dur ation was less than 1 minute in only one of nine (11%) control biopsie s compared to six of nine (67%) collagen plug biopsies. CONCLUSIONS: A recently developed, expansile collagen hemostatic plug significantly decreases the duration of hemorrhage at renal biopsy sites in an antic oagulated swine model.