Foley’s Catheter

The aim of any medical professional is always the wellbeing and good health of their patients. A good doctor will try their best to proceed with the treatment option that is the most comfortable and effective for the patient. 

The empathy and skill with which a doctor approaches their patient are essential for building trust. It is said that one must always be transparent with their doctor, even if it’s a problem related to your personal parts. Talking openly about any abnormalities regarding bladder problems or abnormalities in the urine, one must approach their doctor upfront. Dealing with various patient problems can require the use of catheters. Read on to learn more.

What is a catheter?

A Catheter is a soft, hollow tube meant to be inserted into the bladder so that urine can be withdrawn or collected. A catheter is often made up of silicone or natural latex. The coating of catheters is made up of polytetrafluoroethylene, hydrogel, or silicon elastomer depending on the duration of the use of the catheter. The process of inserting a catheter into the bladder of a person is known as catheterization. It is commonly used when a person undergoes surgery. 

Why does a person need a Catheter? 

There are several reasons why a person might need a catheter. They are as follows:

  1. When the urine flow of a person is blocked due to reasons like kidney stones, blood clots, etc. 
  2. Lack of voluntary control over one’s bladder.
  3. When there is a need for urine retention.
  4. To empty a patient’s bladder before or during surgery.
  5. For urinating when the patient is in recovery from surgery. 
  6. For measuring residual urine is a person’s bladder.
  7. To gain a sterile urine sample.
  8. For emptying the bladder for diagnostic exams.
  9. To prevent leakage from continuous bladder drainage. 
  10.  When there is an injury to the nerves of the bladder.

What are the different types of catheters?

The catheters can be divided into 3 types based on how they are inserted into the bladder. 

  1. External catheters

These are also known as condom catheters. Using one of these is common for people with functional or mental disabilities like dementia. There is no insertion made in this type of catheter. A condom-like device is placed over the penis and a tube protrudes outwards from the device to a drainage bag. 

The condom catheter must be changed every day. 

  1. Short term catheters

These are also known as intermittent catheters. The need for these catheters might arise after surgery where one might need a catheter to be inserted for emptying the bladder. The catheter is often removed after the bladder has been emptied. It can be inserted via the urethra or an incision with the help of a caregiver or healthcare professional.

  1. Indwelling catheters

They are also known as urethral or suprapubic catheters. This type of catheter is inserted into the urinary bladder via the urethra or through an incision in the abdomen. The catheter can be used for a short or long time, sometimes people have to live with indwelling catheters due to their health conditions. A tiny balloon is present at the inserted end of the tube to prevent the tube from falling out. 

A commonly used Indwelling catheter is the Foley catheter. Let’s learn more about it!

What is a Foley catheter?

A Foley catheter is a semi-rigid, flexible tube catheter that is meant to be inserted into the urethra or via an abdominal incision. The role of this catheter is to drain the bladder of urine and block the urethra. 

The history behind the Foley catheter

Did you know? The name of the Foley catheter can be traced back to its inventor and designer Dr. Frederic Foley who worked as a surgeon in Boston, Massachusetts during the early 1930s.

Structure of the  Foley catheter 

image: Foley catheter

The Foley catheter is a long tube-like structure with lumens at both ends. One lumen opens at both ends and collects the urine into a bag. The other lumen has a valve on the outside that is connected to a balloon on the inside end of the tube. The lumen on this opposite side is the one inserted into the bladder. This end is the one having a small balloon that prevents the catheter from falling out of the bladder. The infusion port for the balloon is labeled with the size of the balloon (5cc or 30 cc) and the size of the catheter.

Another type of Foley catheter is the 3-way catheter. In this catheter, the balloon containing lumen is inserted into the bladder. The opposite end has 3 lumens. One to manage the air pressure of the balloon inside the bladder, one for draining the urine, and one more for irrigation and medication of the bladder. This catheter is used when the patient has undergone urological surgery and needs either medication or cleaning from blood and debris or both.

This mechanism of the Foley catheter makes it easy to use and one of the most used indwelling catheters in healthcare.

image: 2 way Foley catheter

image: 3 way Foley catheter

The Foley catheters are available for use in varying sizes that serve different purposes. They are also color coordinated for better understanding. Let us know more about these specifications.

Color coding and sizes in a Foley’s catheter

The relative size of a Foley catheter is described in French units (Fr). 1 french unit or 1 Fr is equivalent to 0.33mm. This is equivalent to .013″ that is 1/77″ in diameter. Generally, the size of the urinary catheters ranges from 8Fr to 36Fr in diameter. The cross-sectional diameter of a urinary catheter is equal to three times the diameter.

Out body tissue and muscles have the capacity to shrink, expand and contract due to the property of elasticity. The mucosal tissue of our urethra is also elastic. When the catheter is inserted into the ureter the tissue surrounding it encloses on the tube. Considering this reason the catheter is chosen should always be the smallest one that will adequately drain urine. 

Using a large diameter catheter can cause The routine use of large-size catheters diameters can cause more erosion of the bladder neck and urethral mucosa, can cause the formation of stricture, and not allow adequate drainage of peri-urethral gland secretions, causing a buildup of secretions that may lead to irritation and infection later. 

Larger Fr sizes (e.g. 20-24 Fr) are most commonly used for drainage of blood clots post injury, surgery or cancer.  The most commonly utilized indwelling transurethral and suprapubic catheters range from 14 to 16Fr in both adult females and males. A 14 or 16 Fr is also the standard catheter in most commercially available IUC insertion kits or trays. For  adolescents, a catheter of size 14 Fr is often used. However for younger children, pediatric catheter sizes of 6-12 Fr are preferred.  Urological heath Conditions like Kidney stones, surgery on the prostate of genitals, Urinary incontinence may require the use of a Catheter. 

The color-coding on the Foley catheter ranges from yellow-green- 6Fr, Cornflower blue- 8Fr, Black- 10Fr, White- 12Fr, Green-14Fr, Orange- 16Fr, Red- 18Fr, Yellow- 20Fr, Purple- 22Fr, Blue-24 Fr, Black- 26Fr. Even those some colors might have been repeated, it can be considered as the dimensions in mm are usually mentioned. 

Complications related to Catheters

There is a possibility that some people might face some problems because of the material of the catheter, or by the way, it was inserted. Here are some common problems.

  1. Allergy or sensitivity to latex
  2. Urethral injury 
  3. Urinary tract infection
  4. Kidney infection
  5. Bladder stones
  6. Long-term kidney damage
  7. Haematuria (blood in the urine)
  8. Septicemia (blood infection)
  9. Bladder spasms
  10. Skin sores or infection around the suprapubic catheter

How to care for a person with a catheter

To clean an indwelling catheter make sure to keep the area around the catheter clean. The catheter exiting the body must be washed with soap and water to prevent any infections. After every bowel movement, proper hygiene must be maintained. 

For a suprapubic catheter, make sure to clean the area on your abdomen where the catheter is inserted with soap and water and dry it completely with clean gauze to avoid the risk of infections. 

Providing the right treatment and care for your patients is what makes a doctor so respectable and dear to their patients. So keep learning and growing ahead in your career. Good luck! 

References:

  1. Jahn P, Beutner K, Langer G. Types of indwelling urinary catheters for long-term bladder drainage in adults. Cochrane Database of Systematic Reviews 2012, Issue 10. Art. No.: CD004997. DOI: 10.1002/14651858.CD004997.pub3.Newman DK, Cumbee RP, Rovner ES. Indwelling (transurethral and suprapubic) catheters. In: Newman DK, Rovner ES, Wein AJ, editors. Clinical Application of Urologic Catheters and Products.  Switzerland: Springer International Publishing;2018,  47-77.
  2. Newman DK. Devices, products, catheters, and catheter-associated urinary tract infections. In: Newman DK, Wyman JF, Welch VW, editors. Core Curriculum for Urologic Nursing. 1st ed. Pitman (NJ): Society of Urologic Nurses and Associates, Inc; 2017, 439-66.
  3. Urinary catheters: MedlinePlus Medical Encyclopedia at https://medlineplus.gov/ency/article/003981.htm accessed on 3rd February 2022

FAQs

What is a catheter?

A Catheter is a soft, hollow tube meant to be inserted into the bladder so that urine can be withdrawn or collected.

Why does a person need a Catheter?

Reasons Catheter can be used:
1. When the urine flow of a person is blocked due to reasons like kidney stones, blood clots, etc. 
2. Lack of voluntary control over one’s bladder.
3. When there is a need for urine retention.
4. To empty a patient’s bladder before or during surgery.
5. For urinating when the patient is in recovery from surgery. 
6. For measuring residual urine is a person’s bladder.
7. To gain a sterile urine sample.
8. For emptying the bladder for diagnostic exams.
9. To prevent leakage from continuous bladder drainage. 
10. When there is an injury to the nerves of the bladder.

What are the different types of catheters?

Catheters are of 3 types:
1. External catheters
2. Short term catheters
3. Indwelling catheters

What is a Foley’s catheter?

A Foley catheter is a semi-rigid, flexible tube catheter that is meant to be inserted into the urethra or via an abdominal incision. The role of this catheter is to drain the bladder of urine and block the urethra. 

What are the color codes of Foley’s Catheter?