Despite their widespread and even integral use in many diagnostic, interventional and minimally-invasive surgical procedures, today’s catheters are often viewed primarily as a flexible tubing delivery system with little regard to the intricacies involved in their design and manufacture. But in fact, the design and fabrication processes used in their manufacture is quite complex. And considering the many different types of applications where catheters are used, it’s no wonder.
The Means to an End
When designing a catheter, the application is always a primary consideration. Depending on the procedure, a catheter may need to be more flexible, wider, slimmer or able to handle more pressure or torque. Features like an atraumatic tip or extra coils in the proximal end to promote “steerability” may also need to be incorporated. As a result, the design and manufacturing processes are closely related, and each step of the design process must take manufacturing restrictions into account in order to produce a quality product. At the same time, the manufacturing process must be carefully developed to support consistency and reproducibility from one catheter to the next.
The success of a catheter’s design and, ultimately, function is highly dependent on the materials used in its fabrication. Today, many catheters use cutting-edge polymer materials that are able to support increasing demands for greater tensile strength without a loss of flexibility. When selecting a material, design engineers must carefully evaluate the chemical and physical properties of the materials to meet the demands of novel, minimally-invasive procedures that rely on catheters for device delivery or to perform complex surgeries through tiny incisions.
In addition to the material itself, some of the factors that need to be considered during the design phase include whether or not to incorporate features like:
- braided wires or mono filaments to add strength and control while still preserving flexibility
- special exterior coatings and lining materials to increase lubricity and reduce friction
- atraumatic tips to prevent damage to the intimal tissues
- variations in flexibility and durometry (“hardness”) across the length of the catheter to suit specific needs
- radiopacity at the distal end and elsewhere for tracking and visibility throughout the procedure
Within each of these options, other variables exist which must be considered to achieve the highest levels of performance. For instance, in braided catheters features like the pick count (the number of times a braid crosses itself in a given space), the pattern of the braid and the shape of the wire can all affect the final product in profound ways.
The Extrusion Process
The extrusion process also has a significant bearing on the final product and on the material itself, and the need for precision in every phase of manufacturing can’t be overstated. Indeed, different materials react differently to the thermal effects of extrusion, and understanding how to manipulate these effects can play a critical role in features like flexibility and strength.
Once the tubing is extruded from the die head, the cooling process begins, and even here, slight variations can have a major bearing on the final product, causing changes in crystallization rates that have a direct effect on the catheter’s flexibility, strength and other key properties. It’s easy to see why maintaining close control over the extrusion process is essential to achieving the highest quality final product.
Via Biomedical: Meeting the Demand
With the introduction of new, minimally-invasive surgical techniques on the rise, the demand for catheters that are stronger, more flexible, more “steerable” and more kink-resistant is also increasing, and Via Biomedical is there to meet those challenges. As a leading global provider of state-of-the-art catheters, Via Biomedical is uniquely positioned to provide the most advanced solutions using state-of-the-art materials and technology for superior results. To learn more about Via Biomedical’s products or to request a quote, visit the Via Biomedical website or send an email to firstname.lastname@example.org.