YY/T 0872-2013 Test methods for ureteral stents English
1 Scope
This standard covers the referee test methods for evaluating the performance characteristics of a single-use ureteral stent with retaining means at both ends, during short term use for drainage of urine from the kidney to the bladder. These stents are typically available in diameters of 3.7 Fr to 14.0 Fr, and lengths of 8 cm to 30 cm, and are made of silicone, polyurethane, and other polymers. They are provided non-sterile for sterilization and sterile for single-use.
Long-term indwelling usage (over 30 days) is encountered with this product, but not commonly, and is therefore considered an exception to this standard. Similarly, the use of ureteral stents for non-ureteral applications such as nephrostomy and ileostomy is excluded from the scope of this standard. Non-sterile ureteral stents are also excluded due to the variability of hospital sterilization equipment and processes and the resulting effects on ureteral stent characteristics.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB/T 528 Rubber, vulcanized or thermoplastic - Determination of tensile stress-strain properties
GB/T 16886 (all parts) Biological evaluation of medical devices
YY/T 0586 Medical polymer products - Test methods of radiopacity
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
artificial urine
a solution of organic and inorganic compounds that closely simulates the chemical and physical properties of normal human urine. Artificial urine will be used as a substitute for human urine to simulate the effects of human urine on ureteral stents.
3.2
bladder retention means
physical feature of bladder end of stent that prevents movement of stent out of bladder
3.3
break strength
peak tensile load required to break stent
3.4
cross section
view of stent tube when cut in a plane perpendicular to length of stent
3.5
distal
situated away from the point of origin. The distal end of a stent is the end that resides in the bladder, also known as the bladder end
3.6
drainage holes
holes in wall of stent tubing that allow flow of urine into and out of lumen of stent
3.7
dynamic frictional force
resistance to relative motion between two surfaces during motion. This force is defined as the coefficient of kinetic friction multiplied by the force acting on the surface of the material in a plane perpendicular to the surface.
3.8
elongation
expressed as a percent, is equal to the change in length of a sample of tubing at failure divided by its original length. Stretching of the tubing is produced by tensile loading.
