Catheter manufacturing

Raw materials that are commonly used for Catheter manufacturing?

• Polyethylene
• Polypropylene
• Polyurethane
• Polycarbonate
• Polyethermide
• Pebax
• Nylons

How is a catheter made? Let’s take a look at the step by step process by which the most basic of catheters, namely the Foley catheter, is made. Most catheters are still made using this process, with added procedures for improved flexibility, the addition of special instruments, radioactivity for visualization through x-rays, CT scan, MRI and other imaging procedures, etc.

What is a catheter?

A catheter is a tube that is inserted into your bladder, allowing your urine to drain freely.

The most common reasons for using a catheter are:

• To rest the bladder following an episode of urinary retention
• To rest the bladder after surgery – most commonly bladder, bowel or urinary tract surgery
• For conditions such as stroke or multiple sclerosis
• Due to complications of diabetes
• Because of spinal injury
• For conditions which affect the nerves that supply the bladder.
• If you don’t fully understand why you have to have this procedure or how the equipment is used discuss it with your doctor or nurse.

It is important that you let your doctor or nurse know if you are taking blood-thinning medications such as:

• Aspirin
• Wayfaring
• Clopidogrel 

Different types of catheters

There are different types of catheters available.

Self-intermittent catheterization

Self-intermittent catheterization is a non-sterile clean procedure which has a low risk of infection when performed in your own home.

Urinary and suprapubic

Urinary and suprapubic catheters can stay in place for a short time For a few days or weeks A longer period of time to manage your bladder.

The drainage system used may be one of the following:

• A leg bag on continual drainage which is connected to a larger volume drainage bag/bottle at night time
• A catheter valve which is drained every 2 to 3 hours during the day and can be attached to a drainage bag/bottle at night.
• Don’t be afraid to ask your nurse questions about your catheter and the drainage system being used.
• It is important that you let your doctor or nurse know if you have a latex allergy (an allergy to rubber). For example, you may react to rubber bands, gloves or condoms.

Catheters are made from both rubber and non-rubber materials such as silicone. It is important to use the correct type of catheter and a non-rubber catheter is used if you are allergic to latex.

Raw Materials

Foley catheters are made from either silicone or latex rubber, depending on the use.

Design

Foley catheters are made of latex or silicone rubber. Silicone rubber catheters are believed to be superior to latex catheters, as silicone is more biocompatible, causes less cell death, less likely to become encrusted, and more resistant to bacterial colonization. The catheter can either have two or three outlets. In a two-way catheter, one outlet acts a urine output and the other inflates the balloon. A three-way Foley catheter has the same function as a two-way catheter, but uses the third outlet for bladder irrigation.

Foley catheters vary in size from 12 fr to 30 fr (4 to 10 mm) in diameter, with the standard being 14 fr (4.6 mm). The balloon itself varies in size from 5 cc to 30 cc, depending on the needed use. The balloon can either be filled with sterile water or air. The catheter can also be attached to a drainage bag.

The catheter Manufacturing Process

The first step in the manufacturing of a Foley catheter is the production of the long, thin tube that will be inserted into the bladder. The liquid rubber silicone is poured into a room temperature vulcanization (RTV) rubber mold. The mold is shaped like the desired catheter with either two or three outputs.

The silicone is then heat cured. This procedure can take anywhere from 0.5 to 40 hours. Once cooled, the tube is withdrawn from the mold. A small opening is then punched in the distal end of the tube furthest away from the two outputs.

A thin band of cured latex is slipped over the tube by hand to form a sheath around the tube. It is positioned so that the latex covers the opening that has been punched in the tube.

To form the balloon, the entire length of the tube is dipped in latex, which creates an overcoat layer and bonds the band to the tube proximate to the distal and proximal ends of the band, forming the balloon. This A Foley catheter.

A Foley catheter.

adds to the thickness of the balloon and is used to adjust the outer diameter of the tube to the desired size. The catheter is then transported to the packaging center where it is put into a kit with a needleless syringe (to fill the balloon) and a drainage bag.

Quality Control

Quality control is built into each step of the manufacturing process. The machine operations check the final product of each stage in the process. The thermoplastic materials are immersed in liquid to ensure that defects are not present and that there will not be any leakage.

Byproducts/Waste

Any material deemed to be defective is either discarded or recycled depending on the severity of the damage. Since the product is directly related to human health, the materials must be of the highest quality.

The Future

A new use of the catheter is being tested in medical facilities for the purpose of dissolving clots or blockages in the coronary arteries. Once the catheter is positioned in the coronary artery, the tip of the catheter acts much like a showerhead, spraying six jets of saline around the clot. These saline streams break down the clot and the vacuum-like natures of the pumps force the debris out of the artery. With the clot gone, doctors can proceed with balloon angioplasty to repair the fatty blockage, which caused the clot to lodge there in the first place.