| Popis: |
Standardized reproducible tests have been developed to determine the biomechanical performance of cardiovascular needles. The parameters used to assess performance were sharpness, resistance to bending, and ductility. Three comparable groups of taper point cardiovascular needles were selected from different manufacturers for these biomechanical studies. The results of this testing demonstrated that needle geometry, needle composition, and the manufacturer were important determinants of needle performance. When needles of comparable size were evaluated, the biomechanical performance of cardiovascular needles manufactured by Ethicon, Inc., were superior to needles produced by other manufacturers. The superior performance characteristics of the cardiovascular needles produced by Ethicon, Inc., were related to their unique stainless steel alloy, American Society for Testing Materials 45500, which has greater yield and tensile strengths than the alloy used by the other manufacturers. Scanning electron microscopic photographs of the Ethicon, Inc., needle revealed a uniform taper point geometry without irregularities. The deformations of the points of cardiovascular needles produced by the other manufacturers could alter their performance. |
