To get a better idea of the importance of New England Catheter’s capabilities for medical device customers, Medical Design Briefs spoke with Mike Boivin, manufacturing manager at New England Catheter.

Medical Design Briefs: Let’s start where customers often start, with a need for help getting a great new product configuration past the design stage and into development. What kinds of resources can NEC bring to these early-stage challenges?

Mike Boivin: NEC is proud of having a very good in-house engineering staff with extensive experience in developing product and bringing it to fruition. Added to our knowledge from being in the business for so long — more than 30 years — we also use 3D drawing software and fluid dynamic analysis software, both of which help us to reduce development time for our customers.

Prototyping and getting customers’ product onto the market as soon as possible is a very big part of our business. In the past, completing an extrusion project often involved something of a trial and error approach, and it could take many iterations to get everything right. But using today’s sophisticated software tools, we’re now able to model many of our projects before ever producing a prototype. This helps to reduce the number of iterations, which in turn gets the customers’ product to the market faster.

We’re also able to do most of our own tool making. We build the majority of our own extrusion tooling in-house, and when it’s needed we can fabricate our own production equipment. We also have a very extensive testing laboratory.

MDB: From the customer’s point of view, what’s the advantage of having such extensive in-house machine shop and testing facilities?

Boivin: Having all these facilities available in one location enables us to support customers’ needs much more efficiently. When a customer’s job requires the fabrication of extrusion tooling, we can do it right here, and sometimes turn it around in less than a week. If needed for the requirements of a special job, we can also fabricate or modify our own equipment.

The same kind of efficiencies apply to our in-house testing capabilities. The nice thing about testing in-house is that we’re able to characterize the results of our own development processes, so that we can rapidly optimize the design characteristics of a customer’s project. Typical types of testing that we perform in-house include torque testing, tensile and elongation testing, flexibility testing, and crush-resistance testing. Customers are often seeking to achieve a specific level of a certain attribute; our in-house testing facility makes it much quicker for us to help optimize key product characteristics.

MDB: How broad is the variety of catheter tubing types manufactured by NEC?

Boivin: We manufacture an extremely wide variety of both single- and multilumen tubing, in sizes ranging from less than 2 French to more than one inch. The multilumen extrusions that we produce can incorporate everything from basic geometries using simple round lumens to more challenging geometries that might result in oval or crescent-shaped lumens.

We’re also very proud of our capabilities for producing reinforced tubing — and especially complex braided reinforcement of multimen tubes. We can reinforce with many different materials, including stainless steel, monofiliments, and high-strength filaments. Our reinforcing operations offer some strong benefits to our customers, and it seems that there has been a little more activity in that area lately.

We can also produce tubing that employs multiple layers of materials. Using different kinds of plastics to create multilayer tubing enables us to precisely match our customers’ requirements for characteristics such as lubricity, hardness, softness, or temperature requirements.

MDB: In terms of functionality, how does reinforcement contribute to the characteristics of tubing?

Boivin: In many cases, reinforcement is needed to improve the torque response of a particular type or size of tubing. But it is also used to increase overall column strength. Adding reinforcement can make for a more robust tube, which is necessary for some applications.

MDB: What kinds of configurations are available for reinforced tubing, and what applications are they typically suited for?

Boivin: Typically, the need for reinforcement has a lot to do with how tortuous a path the catheter will be expected to follow, and how sharp the bends that it will encounter. We provide reinforcement either through braiding or spiral wrapping. Braiding tends to increase overall column strength as well as the torque response of the shaft, depending on the design of the braid. Spiral wrapping is used to make a shaft more robust by improving its crush resistance, or what we call “hoop strength.”

We also make hybrid tubing, which permits conductors to be integrated into the tubing. Conductors permit current to be transmitted down the shaft in order to energize an electrosurgical device. We can also incorporate signal wires that can be used to initiate connectivity with other microelectromechnical (MEMS) devices, such as ultrasonic sensors.

MDB: Do today’s catheters require more complex extrusions than those of the past?

Boivin: It seems we receive more complex orders all the time. One common denominator among such orders is a desire to achieve smaller overall diameters while maintaining the inner diameter of the channel. Naturally, this means that the wall of the tubing will be much thinner, so any reinforcing that we perform also needs to use materials of a smaller size.

Some of the more complex orders we’ve fulfilled have called for varying the stiffness or the flexibility of the tubing over the length of the shaft. Typically, the body of a catheter’s shaft is relatively stiff, while the distal end tends to be more flexible, with a soft, atraumatic tip. This kind of configuration is commonly needed because the physician will be inserting or moving the shaft through a tortuous path to the area of interest.

We achieve these complex configurations by either varying the resin compounds or the durometers that are used in the shaft, or varying the way that we configure reinforcement materials over the length of the shaft. Taken together, such variations in design and processing enable us to supply customers with exactly the column strength and flexibility their applications require.

MDB: Is the increased complexity of the catheters you’re seeing representative of companies trying to provide access to parts of the body that in the past would not have been accessible by catheters?

Boivin: Yes. Naturally, surgeons would prefer to use the body’s natural openings, such as the mouth or nasal passages, to reach their target of interest. In recent years, there has been a lot of interest in developing sophisticated catheters for use in natural orifice transluminal endoscopic surgery (NOTES). And surgeons are also trying to reach previously inaccessible areas of the body, such as the peripheral arteries and smaller cavities of the hands and feet.

MDB: There’s a lot more going on at the distal end of a catheter than most people usually think about.

Boivin: That’s right. We’ve witnessed a tendency for companies to want to integrate even more capabilities into their catheters—especially with regard to electrical conductors. And meanwhile, they also want to keep the overall package at the same size—or to make it even smaller.

MDB: What does NEC offer with regard to finishing operations?

Boivin: We can perform quite a variety of specialized value-added operations on tubing. One area of expertise is the thermal bonding of radiopaque tips and flared hubs to tubing shafts.

Sometimes a customer requires delivery of tubing shafts in a very specific shape that will permit access to a certain geometry of the human body. To meet such needs, we are able to build fixtures and perform thermoforming in-house.

We can also perform laminating. That’s especially useful if we’re called upon to add a reflow capacity to a preexisting catheter design.

MDB: Do customers often ask for additional post-processing services?

Boivin: Yes. Among the post-processing services we provide are centerless grinding, cutting tubing to precision lengths, and heat treatment of shafts in order perform annealing or stress relief. We also offer parylene coating, which imparts a lubricious coating to the surface of the tubing.

MDB: What is the biggest challenge for companies designing catheters? What is the one issue that arises repeatedly, suggesting that companies are really struggling with it?

Boivin: Very often, a company’s biggest challenge is how to match their tubing requirements to the actual needs of their product’s application. In many cases, companies are uncertain what the most important characteristics of their tubing may be, or precisely what levels of those characteristics need to be achieved.

For instance, a company may know that it wants a catheter that can provide access to the abdomen, but it may not know how stiff the tubing needs to be, or what diameter may be needed to give their device free passage. In such a case, it might take one or two prototyping iterations before the tubing can be fully characterized for production.

MDB: It seems there’s still a little bit of trial and error there. What’s NEC’s process for helping companies find the information they need? Are companies still producing prototypes and doing animal testing?

Boivin: Yes, companies do create prototypes for testing on animal or cadaver anatomies. This enables them to see how the product works initially, before the design is refined and finalized.

But of course companies want to minimize the amount of such testing they conduct, and to move to final product configurations as quickly as possible. And that’s why we encourage companies to engage us as early as possible when they’re trying to develop products. We like to be involved on the front side of product development so that our customers can make the best use of our expertise in the field.

No matter what kind of catheter tubing is being considered, it’s highly likely that we’ve previously created products for very similar applications.

MDB: So NEC can offer shortcuts based on its experience in the field?

Boivin: We hope so. And we have an extensive in-house inventory of samples. So if a company is looking for tubing of a certain size or material, there’s a good chance we can provide a sample that is close enough for testing. Using such actual samples at least enables companies to conduct preliminary testing, to determine if the sample is close to meeting the requirements for their application.

MDB: What kinds of customers typically need NEC’s services?

Boivin: Our core business is delivering components to original equipment manufacturers (OEMs) or contract manufacturers of medical devices.

We also deliver a lot of custom-braided tubing to endoscopic device repair facilities. Custom braiding is an important service that we can provide to those customers.

And we have always been involved with academic institutions. Our customers in those settings include many of the nation’s leading experts in performing healthcare research.

MDB: How do you expect catheter designs and applications to evolve in the future, and what role do you see NEC playing in supporting those changes?

Boivin: I’m sure they’re only going to become more demanding. Building on current trends, it’s likely that manufacturers will continue seeking to increase the functionality of each shaft and tube, typically by integrating more lumens or adding electrical conductivity. And they’re also going to continue attempting to reduce the overall package size.

Correspondingly, NEC is always increasing its technical capabilities and trying to push the limits of what we can do. We’ll continue to work directly with our customers to provide them with the products they need — efficiently designed, developed, manufactured, and delivered — just as we’ve always done.

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