One of the most common complications associated with long-term catheterisation is blockage. Some people are more at risk of catheter blockage than others. The reason for this are unknown.
A blockage is when urine fails to drain from the catheter. This may result in the urine bypassing the catheter (draining from the urethra or around the catheter itself) or retention of urine in the bladder.
Blockage may lead to immediate problems such as autonomic dysreflexia which needs to be managed quickly, or more long term problems such as urinary retention.
Why blockage occurs
A blockage may have a simple cause. These include constipation, kinked tubing, tight clothing, incorrect placement of the drainage bag, a full drainage bag, or blocking of the catheter by mucous from the bladder wall.
Around 50% of people with IDC or SPC catheters will experience blockages due to encrustation. Encrustation is caused by bacteria that produce an enzyme called urease. Urease makes the urine less acidic and more alkaline. Alkaline urine is the ideal environment for crystal formation and these crystals can stick to the inside of the catheter. As the bacteria multiply, more crystals may form which may impair or even stop the flow of urine out of the catheter.
If you want to know more see: Urinary catheter blockage
If your catheter becomes blocked, change the catheter. If this is not possible you will need to perform a bladder washout. This practice is not recommended routinely but may be necessary in the event of autonomic dysreflexia caused by bladder distension.
If your catheter blocks at a regular interval, such as every 4 weeks, you should change your catheter routinely before it blocks, such as every 3 weeks.
Sometimes you may need a good washout of your bladder to help clear any debris. This is done in hospital. Speak to the spinal urology nurse if you are having regular blockages.