YY/T 1814-2022Implants for surgery-Synthetic non-absorbable patch-Hernia repair patch (English PDF)

3.1 Hernia

Any organ or tissue that has departed from its original location and entered another site by passing through normal or abnormal - whether congenital or acquired - weak points, defects, or orifices within the human body.

3.2 Hernia repair

This method utilizes synthetic materials as patches to reinforce weak points, defects, or gaps where a hernia has formed. It overcomes the disruption to normal anatomical structures inherent in traditional surgery (i.e., suture-only repair without the use of a patch) and features distinct anatomical layering.

3.3 Non-absorbable material

Materials that are not absorbed by the human body after implantation (currently, those commonly used in clinical practice include polypropylene, polyester, polyvinylidene fluoride, etc.).

4.1 Physical properties

4.1.1 Appearance

It shall be free of stains or foreign matter, as well as tears, abrasions, and particulate matter.

4.1.2 Thickness

It shall comply with the manufacturer's specifications.

4.1.3 Tensile strength

The longitudinal and transverse tensile strengths shall be >= 16 N/cm.

4.1.4 Tensile elongation

The tensile elongation at a tensile strength of 16 N/cm - both in the longitudinal and transverse directions - shall comply with the manufacturer's specifications.

4.1.5 Seam strength

The seam strength shall be >= 16 N.

4.1.6 Bursting strength

The bursting strength shall be >= 20 kPa.

4.1.7 Tear strength

The tear strength shall be >= 16 N.

4.1.8 Pore size

The manufacturer shall describe the pore size of the hernia repair patch. The pore size of the hernia repair patch shall fall within the range specified by the manufacturer.

4.1.9 Connection force

For multi-layer hernia repair patches, the manufacturer shall clearly specify the method of connection, and the connection strength shall be >= 16 N.

4.2 Chemical properties

4.2.1 General provisions

The chemical properties of the hernia repair patch shall be subjected to the following tests in the supplied state. If substances that may affect the pass/fail determination of the test results specified in 4.2.3, 4.2.4, 4.2.5, and 4.2.6 have been introduced during the product manufacturing process, such test items shall be specifically identified, subject to additional requirements, and tested in accordance with the provisions of 4.2.8.

4.2.2 pH

The difference between the pH value of the hernia repair patch test solution and that of the blank solution shall not exceed 1.5.

4.2.3 Trace elements and total heavy metals

The content of nickel, cobalt, copper, arsenic, mercury, lead, chromium, cadmium, and other elements introduced during the manufacturing process - as well as the total heavy metal content - in hernia repair patches shall be less than the specified limit values (µg/g).

NOTE. The maximum limits for trace elements may be established by [2-6] in Bibliography.

4.2.4 Reducing substances

The difference between the volumes of 0.002 mol/L potassium permanganate solution consumed by the hernia repair patch test solution and the blank solution shall not exceed 2.0 mL.

4.2.5 UV absorbance

The absorbance of the hernia repair patch test solution shall not exceed 0.1 within the wavelength range of 220 nm~340 nm.

4.2.6 Evaporation residue

The residue in 50 mL of the test solution shall not exceed 5 mg.

4.2.7 Infrared spectroscopy

The manufacturer shall provide a standard infrared spectrum corresponding to the hernia repair patch and clearly identify the positions of the characteristic peaks. The deviation of the measured absorption band wavenumbers from the specified wavenumbers shall be less than 0.5%.

4.2.8 Supplementary test items

Manufacturers shall provide a detailed description of any unique chemical substances utilized during the product manufacturing process (e.g., polymerization aids, coatings, pharmaceutical ingredients, etc., that would significantly impact the test results of the aforementioned inspection items), and shall additionally specify the corresponding inspection parameters (including sample preparation methods, test methods, result calculation procedures, etc.).

4.2.9 Ethylene oxide residue

For hernia repair patches sterilized with ethylene oxide, the residual ethylene oxide content shall not exceed 10 µg/g.

4.3 Biological properties

4.3.1 General principles

It shall comply with the relevant requirements of GB/T 16886.1.

4.3.2 Sterility test

It shall comply with sterility requirements.

4.3.3 Bacterial endotoxin test

It shall be less than 0.5 EU/mL.

4.3.4 Biological evaluation

Biological evaluation is conducted in accordance with the principles of GB/T 16886.1.

5.1 Physical test

5.1.1 Appearance

Visual inspection. The results shall comply with the requirements of 4.1.1.

5.1.2 Thickness

Measure using general-purpose measuring instruments. The results shall comply with the requirements of 4.1.2.

5.1.3 Tensile strength

The procedure shall be carried out in accordance with the method specified in GB/T 3923.1.The results shall comply with the requirements of 4.1.3.

5.1.4 Tensile elongation

The procedure shall be carried out in accordance with the method specified in GB/T 3923.1.The results shall comply with the requirements of 4.1.4.

5.1.5 Seam strength

A suture of sufficient tensile strength is passed through the hernia repair patch at a point 5 mm~10 mm from one edge, forming a semi-loop. The suture is then withdrawn at a speed of 50 mm/min~200 mm/min. The type of suture used shall be recorded. The magnitude of the tensile force required to either pull the suture out of the patch or cause damage to the patch constitutes the patch's suture strength. The results shall comply with the requirements specified in 4.1.5.

5.1.6 Bursting strength

The procedure shall be conducted in accordance with the method specified in A.5.3.5 of YY/T 0500-2021.The results shall comply with the requirements of 4.1.6.

5.1.7 Tear strength

The procedure shall be carried out in accordance with the method specified in GB/T 3917.2.The results shall comply with the requirements of 4.1.7.

5.1.8 Pore size

The procedure shall be conducted in accordance with the method specified in A.5.2.1 of YY/T 0500-2021.The results shall comply with the requirements of 4.1.8.

5.1.9 Connection force

Secure the connecting sections of the multilayer hernia repair system separately within the grips of a materials testing machine. Apply tension at a speed of 100 mm/min. The tensile force required to cause the connection point to rupture constitutes the connection strength of the multilayer hernia repair system. The results shall comply with the requirements specified in 4.1.9.