General Purpose Tubing
For many single-use medical tubing applications, such as intravenous (IV) lines, transparent polymers are required for clinicians to assess fluid or gas flow through the tube. These tubes require polymers that are resistant to a wide range of cleaning agents and sterilization methods, and must be readily bondable to injection molded fitting and connectors. Common applications for such tubing include:
- Intravenous (IV) tubing
- Umbilical artery catheters
- Infusion tubing
- Nasogastric tubes
- Peritoneal dialysis tubing
- Hemodialysis tubing
The two most commonly used catheters in the medical device market are the urinary catheter and the vascular catheter.
- Urinary catheters are used to collect and drain urine from the bladder, diagnose disorders in the lower urinary tract, monitor urine output, and introduce medication. For maximum flexibility, low durometer polymers, such as soft TPU, Pebax, and styrenic block copolymers are all candidates for these applications.
Vascular catheters are used to gain access to the blood vessels of the human circulatory system in order to perform a variety of diagnostic and therapeutic procedures depending on the type of device.
- Central Venous Catheters are used when patients need IV medicines and fluids. The catheter can be placed at a number of defined strategic locations in the body and can remain for several weeks. For improved patient comfort, low durometer polymers, such as Isothane 5075A, are considered for these applications.
- Diagnostic Catheters are short term use devices used to diagnose artery disease. For optimal rigidity to push the catheter to the designated site while still maintaining flexibility to navigate vascular pathways, Pebax® 7033 SA 01 MED and 7233 SA 01 MED are often considered. For improved rigidity and pushability Rilsan® BMNO and Rilsamid® AMNO are considered.
- Guiding Catheters are used to navigate to a designated site and then allow the physician to pass a variety of instruments through the catheter for treatment. Guide catheters are often complex constructions with braid reinforcements, lubricious liners and varying materials along the length. Lubricous lines may use low friction fluoropolymers, such as Kynar Rx® 752 or Pureflon HC-20 MED. Outer layers of these catheters may use Pebax® 7233 SA 01 MED at the proximal end for pushability and Pebax® 3533 SA 01 MED at the distal end for flexibility.
- Angioplasty Catheters, also known as PTCA catheters (percutaneous transluminal coronary angioplasty), include balloon dilation catheters and stent delivery catheters. Balloon dilation catheters are used to compress the blockage or stenosis against the artery wall. Stent delivery catheters are used to install a stent inside the artery to support arteries that are weakened by the stenosis. Pebax® 7033 SA 01 MED and Pebax® 7233 SA 01 MED provide flexibility to navigate the vascular pathways to the blocked region and the necessary mechanical strength for transmission of insertion forces and resistance to internal pressure to inflate balloons.
Catheter constructions are often comprised on multi-layer extrusions to enable complex devices with a unique hybrid of material properties. However, often times materials used within these multi-layer constructions (such as Pebax®, TPU and HDPE), are not compatible. Tie-layers are therefore designed to bond materials that typically will not adhere to each other during processing. These tie layers can be accomplished with SK Orevac tie layer materials or copolymer blends containing EVA.