The Major factors which continue to favour its use
are:
-
Transparency
- Range of flexibility
- Low toxicity
- Chemical stability
- Ease of fabrication
- Biocompatibility performance
- Sterilization performance
- Cost effectiveness
Some of the major specific component applications for PVC
include blood and blood-component storage bags, cannulae, catheters, drip
chambers, enema packs, endotracheal tubes, haemodialysis sets, heart-lung
by-pass sets, needle hubs, urology products and x-ray opaque tracer filaments.
The range of material properties catered for in this list includes a wide
range of flexibility for transparent tubings, rigid compositions for check
valves & needle hubs and barium sulphate grades for x-ray traceability.
CATHETERS AND CANNULAE
Products range from relatively simple tubing with a
virtual gravity feed application to sophisticated cardiovascular catheters,
which permit a full scope of diagnostic, monitoring and therapeutic procedures.
The traditional method of by-pass involved invasive
surgical procedures. By
comparision, the use of “angioplasty” catheter techniques has proved
beneficial as it avoids surgery and is therefore cheaper than coronary artery
by-pass and is much less traumatic for the patient.
The bulk of catheters sold are still basic, low
specification products offered by well-established specialist companies who have
little opportunity to achieve product differentiation on the basis of
technology. They look to branding,
packaging and pricing as the main strategies used in gaining market growth
assisted by the versatility of PVC as the major material choice.
RENAL CARE PRODUCTS
The world market for renal dialysis products is still
growing strongly, developing new treatment modes and demonstrates continuing
scope for new innovations.
There are currently 460,000 dialysis patients throughout
the world and numbers are increasing by 7 to 8 percent annually.
During the 1990’s technology will develop mainly
through the improvement in product efficiency and by advances in manufacturing
process which will in turn lead to lower production costs. These positive trends within the dialysis market towards cost
reduction and greater patient comfort are expected to support continuing demand
for PVC biomaterials throughout this decade. PVC materials in the form of flexible containers, tubings, connectors,
fistulas and cannulae form the major polymer components in the product design.
Haemodialysis is the most common form of dialysis
treatment and is currently employed in 85% of cases where blood is transported
outside the body using flexible PVC tubing, with the addition of an
anticoagulant.
Peritoneal dialysis is an alternative form of dialysis,
which differs from haemodialysis in that the blood purification does not occur
outside the body. PVC compositions
have and will continue to play a principle role in effectively introducing these
treatments with considerable benefit to the patients concerened.
TRANSFUSION SUPPLIES
This sector of the market which represents almost 10% of
world-wide demand for disposable medical devices can be signled out as the most
critically demanding and perhaps the most successful in employing the unique
properties of flexible PVC compositions for the collection, storage, separation
and delivery of blood and blood components.
The introduction of a system of PVC packs with integral
tubing for collection processing and storage and the development of high speed
refrigerated centrifugation has provided the means of preparing sterile blood
components.
The use of flexible PVC compounds has provided enormous
benefits to transfusion services. Without
these materials, present techniques for the separation of blood components,
plasmapheresis, would be more difficult and costly to perform.
(Ref: Courtesy: Mr. C.R. Blass, Hydro Polymers
Ltd.UK.(PVC Conference – Institute of Materials as published in IPI
Transactions, July/August 1993)
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