YY/T 1770.1-2021Test method for thrombogenicity study - Part 1: Thrombogenicity study in dogs in vivo (English PDF)

Foreword

YY/T 1770 "Medical Device Thrombosis Test" is divided into the following parts.

---Part 1: Thrombosis test in dogs;

---Part 2: In vitro thrombosis test; ... This part is part 1 of YY/T 1770.

This section was drafted in accordance with the rules given in GB/T 1.1-2009.

Introduction

The evaluation of thrombosis of medical devices can be performed in vivo, semi-in vivo and in vitro tests. Vascular patch, intravascular catheter, etc. and circulation When evaluating the blood compatibility of medical devices in contact with blood, it is necessary to evaluate the thrombosis in the body. YY/T 1770 This part is the specific test method for thrombosis test in dogs, which can be used as GB/T 16886.4 Chinese medical device/material thrombosis test Supplement.

1 Scope

This part of YY/T 1770 specifies that dogs should be used for in vivo thrombosis tests when evaluating the blood compatibility of medical devices/materials. Empirical method.

This section is suitable for evaluating whether medical devices/materials cause thrombosis in the body.

2 Normative references

The following documents are indispensable for the application of this document. For dated reference documents, only the dated version applies to this document. For undated reference documents, the latest version (including all amendments) is applicable to this document.

GB/T 16886.1 Biological Evaluation of Medical Devices Part 1: Evaluation and Testing in the Process of Risk Management

GB/T 16886.4 Biological Evaluation of Medical Devices Part 4: Test Selection for Interaction with Blood

3 Terms and definitions

The terms and definitions defined in GB/T 16886.1 and GB/T 16886.4 apply to this document.

4 Test principle

When medical devices/materials come into contact with human blood, the surface of the material may cause plasma proteins (such as albumin and fibrinogen, etc.) to adhere and adhere.

The protein layer will activate the coagulation pathway and cause the adhesion of platelets, forming fibrin and platelet thrombus, respectively, and the two will promote each other.

Finally, a thrombus is formed. Therefore, the medical device/material is implanted in the body through appropriate procedures, and after a certain period of time, observe the device/material table The thrombosis of the surface, implantation site, and distal organs can comprehensively reflect the adhesion of medical devices/materials to proteins in the blood, and activate the blood clotting system.

The path and the conditions that cause platelet adhesion, so as to determine whether the medical device/material has the effect of inducing thrombosis or anti-thrombosis.

5 Experimental animals

The animal species selected in this experiment is dog, and Beagle is the preferred strain, and there is no restriction on male and female (if female animals are used, they should be non-pregnant). Push At least 2 experimental animals are recommended. It is advisable to select suitable experimental animals according to the size of the test samples. The general principle is to choose larger animals as much as possible.

In order to reduce the test error caused by the mismatch between the animal blood vessel and the test sample. All animal testing should be in line with the welfare of laboratory animals Tests are conducted in regulated laboratories.

Note. For intravascular implantation, it is recommended that the cross-sectional area of the implant occupies less than 50% of the vascular cavity. According to the sample size, animal anatomy characteristics, select other bodies The suitability of larger animals is explained.

6 Main instruments and test equipment

6.1 Electronic balance.