Medical Cables: Often Overlooked

Medical cables are as important to a medical device as the device itself. Medical device designers many times focus on the device and overlook the wire and cables that is needed for the device to perform its function. Medical cables tend to be more specialized due to the many types of uses and environments it is subjected to. The wire and cable is many times not thought of until the end of the design process, which may be too late. Knowing your medical cable limitations and the options available to you in the beginning is important especially when designing housing or specifying connectors. Some things to keep in mind when specifying wire and cable for a medical device:

• Size- With the size of devices becoming smaller many times smaller gauge wire and cable is needed. Off the shelf wire and cable usually go as small as 28AWG. Fine wire and custom cable designs are usually needed.
• Flexibility- Handheld devices and medical robots require flexible cables which can withstand repetitive flexing. Higher stranded conductors and sometimes alloys are needed to achieve this.
• Sterilization- Sterilization can be done with alcohol, steam or gamma to name a few. Cable jackets need to withstand the sterilization process.
• Bio-compatibility- Medical grade cables are needed depending on the level of contact with the patient. Bio-compatible and implantable grade compounds are available for medical devices.
• Construction- Cables sending signals, power and even gas/fluid can be constructed in on jacket. Constructions can vary from the simple wire to complex hybrid cable.
• Unique- Medical devices are all unique in regards to application, requirements and environment. You should not use an off the shelf mass produced cable designed for to meet the generic needs of a variety of industries for a specialized medical device.
  

Considering your wire and cable needs from the early stages of your product design will prevent problems down the line in regards to failures in the field, design issues and time constraints. Designing custom medical cables for your application ensures you have a medical device that will exceed performance and longevity you require.

Depending on the type of use a variety of medical grade insulation materials are available. Reusable medical cables are built to endure constant flexing and extended cycles of sterilization. Insulation may be Teflon®, TPE or silicone rubber with TPR or silicone jackets. For disposable medical cables PVC and PE are the insulation most commonly used. Discuss your application with your custom cable manufacture in order to choose the right material for your medical device.

Working with a custom wire and cable manufacture is easier than you think. Custom wire and cable engineers work with you every step of the way to determine and suggest the best materials and construction for your medical application. It's like having a wire and cable expert on your team. Cable designs are usually modified throughout the design process to accommodate changes to the device design. Many custom wire and cable manufacturers are able to produce small quantities for prototypes and clinical trials.