Hemocompatibility testing

Hemocompatibility of blood contacting medical devices has to be evaluated before their intended application. We offer hemocompatibility testing in accordance with ISO 10993-4.

Haemobile

To assess hemocompatibility, blood flow models are often used and can either consist of in vivo animal models or in vitro blood flow models. Given the disadvantages of animal models, such as higher costs, more variability, more time consuming, and insensitivity due to overwhelming short-term effects of tissue injury, in vitro blood flow models are more attractive. We have developed our own in vitro blood flow model [4], see video below, which offers several important advantages:

Use of fresh human blood (within 30 minutes after blood withdrawal).
Pulsatile flow with physiological (wall) shear stress.
The model has a low background for thrombosis.
Low concentration of anticoagulatns, typically 1.5 IU/mL Heparin.
No blood-air interaction (as is the case in the Chandler model).

Basic research

Still having a strong connection with academia, HaemoScan is committed to advancing the Blood-Biomaterial interface research and hemocompatibility testing. In recent years it has done so by reviewing literature and identifying the obstacles of hemocompatibility testing [1] and by describing the state-of-the-art blood–biomaterial interface research [2]. Moreover, we have investigated the necessity of using fresh blood for hemocompatibilty testing [3] and have developed our own in vitro model for hemocompatibilty testing which utilizes pulsatile flow and physiological wall shear stress [4]. Besides intrinsically driven research we perform (basic) contract research, which varies from simple hemolysis testing to custom build in vitro blood flow models. Please feel free to contact us to see if we can be of assistance to your project.

Pre-clinical testing

Application of biomaterials in direct blood contact results in activation of the blood coagulation system and in an inflammatory reaction. These responses of blood are due to the natural response of the host defense mechanism against foreign surfaces. Inadequate control by natural inhibitors results in pathological processes, such as microthrombi generation or thrombosis, bleeding complications, hemodynamic instability, fever, edema, and organ injury. These adverse events can manifest themselves during prolonged and intensive foreign material contact, such as vascular implants and extracorporeal blood circulation.
We are specialized in assessing blood compatibility. Blood compatibility relates to specific interactions between (bio)materials and circulating blood. We perform in vitro tests with fresh whole human blood to determine the hemocompatibility of materials, devices, or material structures using our unique blood circulating model (Haemobile).

ISO 10993-4

Hemocompatibility of blood contacting medical devices has to be evaluated before their intended application. The International Standard ISO 10993-4, for biological evaluation of medical devices (ISO 10993: Biological evaluation of medical devices—Part 4: Selection of tests for interactions with blood), can be used as a directive to evaluate these hemocompatible characteristics.
The standard is applicable to external communicating devices, either with an indirect blood path (e.g. blood collection devices, storage systems) or in direct contact with circulating blood (e.g. catheters, extracorporeal circulation systems), and implant devices (stents, heart valves, grafts). Testing should be performed for five categories, based on primary processes: thrombosis, coagulation, platelets, hematology and complement. In this system all relevant aspects of blood activation are taken into consideration, but, and this is most important, testing should simulate clinical conditions as much as possible.
As one of our experts, Dr Wim van Oeveren, is a member of the ISO committee that drafts and revises the ISO 10993-4 standard, we are very well qualified to help you perform hemocompatibility testing to achieve CE or FDA certification regarding blood compatibility.

References
[1] van Oeveren W. Obstacles in haemocompatibility testing. Scientifica (Cairo) 2013;2013:392584.
[2] Reviakine I, Jung F, Braune S, et al. Stirred, shaken, or stagnant: What goes on at the blood-biomaterial interface. Blood Rev 2017;31:11–21.
[3] Blok SLJ, Engels GE, van Oeveren W. In vitro hemocompatibility testing: The importance of fresh blood. Biointerphases 2016;11:29802.
[4] Engels GE, Blok SLJ, van Oeveren W. In vitro blood flow model with physiological wall shear stress for hemocompatibility testing-An example of coronary stent testing. Biointerphases 2016;11:31004.