The visible damage associated with spinal cord injury (SCI) is very apparent, but the unseen damages often have an even greater impact on the individual
The loss of sexual functionality, bladder and bowel control, the antics of autonomic dysreflexia and the difficulties with temperature regulation are additional disabilities that mess with our self-esteem, self-confidence and perception of quality of life – often more so than the actual paralysis.
It’s useful for caregivers to know how the Autonomic Nervous System (ANS) works; how damage to it plays havoc with our bladders; and how to manage this condition. Readers, please note: I have taken some liberties with describing the very complex nature of the ANS and the consequences of damage on the organs and systems regulated by this system.
However, I trust that caregivers will be left with an understanding of why things are a certain way and
will feel a deeper empathy for the people for whom they are caring.
The ANS
The ANS includes all the nerves that regulate the function of our organs, such as the heart and blood vessels, lungs (breathing, coughing and sneezing), digestive and urinary system (swallowing, vomiting, bowel movement and bladder function) as well as our sexual functionality. It has two components that work together, but largely with opposite functions.
The sympathetic system is responsible for quick responses and is commonly known as the “fright, fight or flight” system; the parasympathetic system is the more laid-back, “breed and feed” or “rest and digest” system. The sympathetic system is, thus, the action component of the ANS, while the parasympathetic system tends to look after the ongoing, quiet processes.
With SCIs, the parasympathetic component (which comes directly from the brain) largely tends to survive, while the sympathetic system is damaged in various ways, as the different sympathetic nerves leave the spinal cord between the first thoracic and the second lumbar vertebra. The extent of sympathetic nerve damage depends on the level of the SCI.
The result is that while the parasympathetic nerves continue to function as usual, the sympathetic system is either non-existent or functions partially or erratically. The interactive functionality of the two components of the ANS is disrupted, often with dramatic consequences for the organs, including the neurogenic bladder.
Impact on the neurogenic bladder
The physiology of the bladder is an extremely complex interplay between the brain, the peripheral nerves (that manage our muscles and movement) and the autonomic nerves. In a nutshell, the bladder has two important muscles that interact with one another in normal bladder function.
The detrusor muscle is in the wall of the bladder and the sphincter muscle is at the opening of the bladder, where it joins the urethra (the pipe through which the urine flows out). In normal bladder function, when the bladder is empty or partially filled, the detrusor is relaxed and the sphincter is contracted.
This allows the bladder to fill up without urine leaking out. When the bladder is full, it sends a message to the brain and the brain tells the detrusor to contract and the sphincter to relax. (This message can be voluntarily held back if you are not close to a toilet.) With SCIs, this messaging system is broken.
Depending on the level at which the damage occurs, there are a number of possible malfunctions essentially disrupting the coordination between the sphincter and the detrusor muscles. If the detrusor contraction is stronger than the sphincter, for example, there is a tendency to incontinence. If, on the other hand, the sphincter is stronger, there is a tendency to urinary retention.
Apart from the obvious embarrassment and discomforts of urinary incontinence and urinary retention, what are the dangers? The three important complications are urinary tract infections (UTI), strictures of the urethra (a result of poor hygiene, inappropriate catheterisation techniques and inappropriate catheters) and hydronephrosis. This third complication is caused by urine retention, where a persistently overfull bladder pushes urine up the ureters into the kidneys and destroys the kidney structure. This can eventually cause kidney failure.
The type of bladder management will depend on the nature of each individual’s neurogenic manifestations. If the problem is incontinence without evidence of urinary retention, the choices are a schedule of bladder emptying (around every three to four hours), incontinence wear or condom catheters.
If the problem is urinary retention, the gold standard is intermittent clean catheterisation, preferably with a sterile pre-lubricated (hydrophilic) catheter. Surgically inserted suprapubic catheters must be kept as a last resort. Indwelling catheters are usually not recommended, as they can cause complications in the long term.
While bladder percussion is a popular and often effective way to stimulate the voiding or draining of the bladder, it is not without dangers. It can push urine up into the kidneys and can aggravate hydronephrosis. The goals of bladder management are:
• To maintain continence and boost the injured person’s self-esteem, self-confidence and quality of life;
• To prevent UTIs;
• To achieve regular, controlled bladder emptying, and to prevent hydronephrosis;
• To select a technique that fulfils the required purpose, but also suits the preference of the patient. It is their life after all.
I always joke that I have three bosses: God, my wife and my bladder. However, our bladders should never control our lives. We must take charge of and manage them. If persons with a SCI are not able to do this for themselves, the caregiver must step in and perform bladder management while respecting the dignity of the patient. This is not a pleasant task, but if done with compassion and empathy, you will be blessed for it.
