Diagnostics with micro-components made of CYROLITE® reduce bleeding risks

Effectively reducing bleeding risks

All major surgical interventions are associated with bleeding risks. In case of bleeding, thromboelastometry is a comprehensive method for fast blood coagulation analysis and diagnosis. The tests are performed with the ROTEM® systems of the Munich-based company Instrumentation Laboratory. Thanks to the diagnostic information, bleeding that occurs during or after surgery can be correctly and promptly diagnosed for targeted treatment. This helps to avoid unnecessary transfusions with possible side effects and complications.

Protecting the blood as a precious asset

Depending on body weight, some 4 to 6 liters of vital blood flow through the vascular system of a typical adult. “When bleeding occurs during surgical interventions, doctors must take immediate action,” explains John Avila, Strategic Marketing Manager, of Instrumentation Laboratory. Quick and effective bleeding management is critical. Thromboelastometry provides physicians with a rapid in-vitro diagnostic assay for monitoring of blood coagulation. The speed and strength of the blood clotting is analyzed with a specific type of instrument which displays a series of measured variables that are characteristic for the formation of a blood clot. “The special feature of the Point of Care (POC) ROTEM® system is that these analyses can be performed near the patient,” John Avila continues. The whole-blood diagnostics generated by the ROTEM® system provide detailed information with which the required measures to treat the bleeding can be determined.

Precise measurement

Both the long established ROTEM® delta model and the fully automated, ROTEM® sigma, are based on a precise opto-mechanical measuring method. A whole-blood sample is placed into a small transparent cylindrical cup, into which a cylindrical pin is immersed. A blood-filled gap of just 1 mm remains between pin and cup. A motor attached to a flexible spring rotates the pin a few degrees to the left and right. The movement of the pin is unimpeded as long as no coagulation occurs. As soon as clotting forms between the cup and the pin, the rotating movement of the spring driven pin is increasingly restricted by the blood clot. The blood contact surfaces of cup and pin are not smooth, but feature microfine grooves. This creates a surface, in which blood clots can “get a hold” and interfere with the movement of the pin. These movement changes are recorded, calculated by an integrated computer, and displayed as a curve (TEMogram). The curves created by the different assays and their numeric values allow physicians to determine a differentiated diagnosis of the clotting abnormalities. “The precision of our method depends largely on the exact representation of the pin’s freedom of movement in the cup,” John Avila explains.

The disposable pin and cup components are made of the specialty plastic CYROLITE® G-20 HIFLO. This grade of the acrylic-based copolymer is specifically designed for medical and diagnostic applications requiring dimensional stability, good flow and processability. It allows for the economical manufacture of sophisticated, small and intricate injection molded parts. This specialty plastic product is, therefore, ideally suited for the precise components used in the ROTEM® system.

Special material for medical applications

Since the sensitive results of this diagnostic procedure significantly depend on component dimensions, a raw material with consistent high quality is essential. CYROLITE® copolymers are designed to meet the stringent requirements of medical and diagnostics devices and have proven successful in a wide range of applications for over 40 years. Typical application areas for CYROLITE® include disposable medical components such as infusion and catheter accessories, blood/plasma separators, chest drainage sets as well as filter and equipment housing. “Our CYROLITE® copolymers are the world's leading plastics for disposable medical and diagnostics devices” says Sergio Corbella, Senior Business Manager for CYROLITE® at Röhm GmbH. They can easily be sterilized with gamma radiation and EtO gas, are highly resistant to chemicals, and have excellent impact resistance with high transparency. All CYROLITE® product grades are BPA free and biocompatible in compliance with USP Class VI and ISO 10993-1.

These features also convinced Instrumentation Laboratory. “All materials that we use must meet the highest quality and safety standards to make sure our diagnostics devices contribute to improving patient care and reducing treatment costs,” John Avila notes. Thromboelastometry represents a crucial element of bleeding management, a building block in the discipline of patient blood management. Numerous studies have shown that unnecessary transfusions are associated with higher mortality, greater complication rates and an elevated risk of infections. Patient blood management therefore focuses on optimizing and conserving the patient’s own blood. Due to improved management – including micro-components made from CYROLITE®– patients typically require fewer allogenic blood transfusions and can, therefore, avoid the associated complications.