A comparative study of PTT and CT tests for coagulation evaluation of cardiovascular system external communicating devices / 生物医学工程学杂志

Based on GB/T16886.4-2003 Standard, the coagulation effects of 5 cardiovascular system external communicating devices made consist of metal and polymer were assessed using the partial thromboplastin time (PTT) and Lee-White coagulation time (CT) tests. The results indicate that PTT test is a stable and valuble method for evaluating the coagulating pathway disturbance of the devices. In line with GB/T 16886.4-2003 Standard, PTT test is a recommendable method for evaluating the external communicating devices Based on GB/T14233.2-2005 Standard, CT test is a method more liable to variation, compared with PTT test. This is due to the complex relativity in the test itself, due to all the factors of coagulating cascade, and due to the individual difference of animal. The question of how to select proper negative control for coagulation evaluation of the Cardiovascular System External Communicating Devices in clinical setting for CT test should be addressed and studied.

A comparative study on dual-magnetic circuit beads and scattering nephelometry coagulometers in coagulational evaluation of blood-contact medical devices / 中国医疗器械杂志

Dual-magnetic circuit beads and scattering nephelometry dual channel semiautomatic coagulometers are used for the coagulational evaluation of the 5 blood contact medical devices which consist of metals and polymers. The partial thromboplastin time(PTT) and prothrombin time(PT) tests are made based on the GB/T 16886.4-2003 standard. The results indicate that the coefficient of variation in the two groups is in the identical order of magnitude. In the PTT tests, they give the similar evaluational results. With the smaller numerical values of the PT tests, the different coagulometers give the high consilience results. So, both of dual-magnetic circuit beads and scattering nephelometry coagulometers are acceptable in the medical devices' coagulational evaluations. But the interpretation and analysis of the results of the small numerical value tests, PT tests for example, should be noticed.