Blood-handling materials

These results support the argument that heparinization can be an important means of preparing the materials needed for the development of improved cardiocirculatory-assist devices and blood handling procedures. 

X Biomaterials has reiterated the need for the development of blood-compatible materials since progress in this field is a condition for advances in the application of cardiocirculatory-assist devices and other procedures which require continuous or intermittent handling of blood (I). For example, the task force has specifically identified the development of small-diameter blood vessel prostheses and chronic blood access catheters as priority applications of blood-compatible materials. Both of these devices are used in low-flow situations where red thrombus formation (i.e., intrinsic clotting system activation) predominates (2). 

While materials that lose heparin at a controlled rate can be clinically acceptable in short-term applications, the long-term use of heparinized materials requires materials that do not lose heparin, yet retain the biological function of the heparin. This investigation and others indicate that these requirements are not mutually exclusive, and that bound heparin can potentially retain its biological activity over the long term. Heparinization can be an important means of preparing the materials needed for the development of improved cardiocirculatory-assist devices and blood handling procedures. 

Blood and body fluids include bulk laboratory specimens of blood tissue, sanen, vaginal secretions, cerebrospinal fluid, synovial fluid, pleural fluid, peritoneal fluid, pericardial fluid, and amniotic fluid. Precautions do not apply to feces, nasal secretions, sputum, sweat, tears, urine, or vomit unless they contain visible blood. Handle free-flowing materials or items saturated to the point of dripping liquids containing visible blood or blood components. Pathological waste includes all discarded waste from renal dialysis contaminated with peritoneal fluid or blood visible to the human eye. Consider solid renal dialysis waste as medical waste if saturated and demonstrate the potential to drip/splash blood or other regulated body fluids. Waste sharps include any used or unused discarded article that may cause punctures or cuts. 

Natural rubber s utility as a blood pump material however was shortlived because of its short fatigue life and its tendency to promote blood clotting and hemolysis. Polyvinyl chloride was used in total artificial hearts (4,5), but this also was soon abandoned because it was cumbersome to handle and the surface was very thrombogenic. 

The rubbers are also used for such diverse applications as blood transfusion tubing capable of sterilisation, antibiotic container closures, electric iron gaskets, domestic refrigerators and non-adhesive rubber-covered rollers for handling such materials as confectionery and adhesive tape. The cold-curing rubbers are of value in potting and encapsulation. 

I I heology is an integral part of life, from decorative paint and movement of volcanic lava to the flow of blood in our veins. This book describes, without the use of complex mathematics, how atoms and molecules interact to control the handling properties of materials ranging from simple ionic crystals through polymers to colloidal dispersions. 

In the absence of a catalyst, the disproportionation is too slow to be observed at room temperature. Rapid, exothermic, and potentially explosive decomposition of hydrogen peroxide is initiated, however, by heat and by a broad range of catalysts, including transition metal ions, certain anions (such as I-), metal surfaces, blood (Figure 14.9), and even tiny particles of dust. Because decomposition is accelerated by light, hydrogen peroxide is stored in dark bottles. It is best handled in dilute aqueous solutions concentrated solutions and the pure liquid are extremely hazardous materials. 

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