Neurogenic bladder dysfunction | |
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A paraplegic patient with neurogenic bladder on regular ultrasound follow-up showing thickened bladder wall with trabeculations and sediments within the bladder. | |
Specialty | Urology |
Complications | Kidney stones, kidney failure, urinary tract infections, hydronephrosis |
Neurogenic bladder dysfunction, often called by the shortened term neurogenic bladder, refers to urinary bladder problems due to disease or injury of the central nervous system or peripheral nerves involved in the control of urination. [1] [2] There are multiple types of neurogenic bladder depending on the underlying cause and the symptoms. Symptoms include overactive bladder, urinary urgency, frequency, incontinence or difficulty passing urine. [3] A range of diseases or conditions can cause neurogenic bladder including spinal cord injury, multiple sclerosis, stroke, brain injury, spina bifida, peripheral nerve damage, Parkinson's disease, multiple system atrophy or other neurodegenerative diseases. Neurogenic bladder can be diagnosed through a history and physical as well as imaging and more specialized testing. [4] In addition to symptomatic treatment, treatment depends on the nature of the underlying disease and can be managed with behavioral changes, medications, surgeries, or other procedures. The symptoms of neurogenic bladder, especially incontinence, can severely degrade a person's quality of life. [2]
There are different types of neurogenic bladder depending on the underlying cause. Many of these types may have similar symptoms.
Uninhibited bladder is usually due to damage to the brain from a stroke or brain tumor. This can cause reduced sensation of bladder fullness, low capacity bladder and urinary incontinence. Unlike other forms of neurogenic bladder, it does not lead to high bladder pressures that can cause kidney damage. [5]
In spastic neurogenic bladder (also known as upper motor neuron or hyper-reflexive bladder), the muscle of the bladder (detrusor) and urethral sphincter do not work together and are usually tightly contracted at the same time. This phenomenon is also called detrusor external sphincter dyssynergia (DESD). This leads to urinary retention with high pressures in the bladder that can damage the kidneys. The bladder volume is usually smaller than normal due to increased muscle tone in the bladder. Spastic neurogenic bladder is usually caused by damage to the spinal cord above the level of the 10th thoracic vertebrae (T10). [5] [6]
In flaccid bladder (also known as lower motor neuron or hypotonic bladder), the muscles of the bladder lose ability to contract normally. This can cause the inability to void urine even if the bladder is full and cause a large bladder capacity. The internal urinary sphincter can contract normally, however urinary incontinence is common. This type of neurogenic bladder is caused by damage to the peripheral nerves that travel from the spinal cord to the bladder. [5]
Mixed type of neurogenic bladder can cause a combination of the above presentations. In mixed type A, the bladder muscle is flaccid but the sphincter is overactive. This creates a large, low pressure bladder and inability to void, but does not carry as much risk for kidney damage as a spastic bladder. Mixed type B is characterized by a flaccid external sphincter and a spastic bladder causing problems with incontinence. [5]
Neurogenic bladder can cause a range of urinary symptoms including urinary urgency, urinary incontinence or difficulty urinating (urinary retention). The first sign of bladder dysfunction may be recurrent urinary tract infections (UTIs).[ citation needed ]
Neurogenic bladder can cause hydronephrosis (swelling of a kidney due to a build-up of urine), recurrent urinary tract infections, and recurrent kidney stones which may compromise kidney function. [7] This is especially significant in spastic neurogenic bladder that leads to high bladder pressures. Kidney failure was previously a leading cause of mortality in patients with spinal cord injury but is now dramatically less common due to improvements in bladder management. [7]
Urine storage and elimination (urination) requires coordination between the bladder emptying muscle (detrusor) and the external sphincter of the bladder. This coordination can be disrupted by damage or diseases of the central nervous system, peripheral nerves or autonomic nervous system. [8] This includes any condition that impairs bladder signaling at any point along the path from the urination center in the brain, spinal cord, peripheral nerves and the bladder.[ citation needed ]
Damage to the brain or spinal cord is the most common cause of neurogenic bladder. Damage to the brain can be caused by stroke, brain tumors, multiple sclerosis, Parkinson's disease, multiple system atrophy or other neurodegenerative conditions. [8] Bladder involvement is more likely if the damage is in the area of the pons. Damage to the spinal cord can be caused by traumatic injury, demyelinating disease, meningitis-retention syndrome, vitamin B12 deficiency, syringomyelia, cauda equina syndrome, or spina bifida. Spinal cord compression from herniated disks, tumor, or spinal stenosis can also result in neurogenic bladder. [5] [8]
Damage to the nerves that travel from the spinal cord to the bladder (peripheral nerves) can cause neurogenic bladder, usually the flaccid type. Nerve damage can be caused by diabetes, alcoholism, vitamin B12 deficiency, or genital herpes. Peripheral nerves can also be damaged as a complication of major surgery of the pelvis, such as for removal of tumors. [5]
The diagnosis of neurogenic bladder is made based on a complete history and physical examination and may require imaging and specialized studies. History should include information on the onset, duration, triggers, severity, other medical conditions and medications (including anticholinergics, calcium channel blockers, diuretics, sedatives, alpha-adrenergic agonist, alpha 1 antagonists). [6] [8] Urinary symptoms may include frequency, urgency, incontinence or recurrent urinary tract infections (UTIs). Questionnaires can be helpful in quantifying symptom burden. [6] In children it is important to obtain a prenatal and developmental history. [9]
Ultrasound imaging can give information on the shape of the bladder, post-void residual volume, and evidence of kidney damage such as kidney size, thickness or ureteral dilation. [9] Trabeculated bladder on ultrasound indicates high risk of developing urinary tract abnormalities such as hydronephrosis and stones. [10] A voiding cystourethrography study uses contrast dye to obtain images of the bladder both when it is full and after urination which can show changes in bladder shape consistent with neurogenic bladder. [9]
Urodynamic studies are an important component of the evaluation for neurogenic bladder. Urodynamics refers to the measurement of the pressure-volume relationship in the bladder. The bladder usually stores urine at low pressure and urination can be completed without a dramatic pressure rise. Damage to the kidneys is probable if the pressure rises above 40 cm of water during filling. [6] Bladder pressure can be measured by cystometry, during which the bladder is artificially filled with a catheter and bladder pressures and detrusor activity are monitored. Patterns of involuntary detrusor activity as well as bladder flexibility, or compliance, can be evaluated. The most valuable test to test for detrusor sphincter dyssynergia (DESD) is to perform cystometry simultaneously with external sphincter electromyography (EMG). [8] Uroflowmetry is a less-invasive study that can measure urine flow rate and use it to estimate detrusor strength and sphincter resistance. [6] [11] Urethral pressure monitoring is another less-invasive approach to assessing detrusor sphincter dyssynergia. [11] These studies can be repeated at regular intervals, especially if symptoms worsen or to measure response to therapies. [9]
Evaluation of kidney function through blood tests such as serum creatinine should be obtained. [6]
Imaging of the pelvis with CT scan or magnetic resonance imaging may be necessary, especially if there is concern for an obstruction such as a tumor. The inside of the bladder can be visualized by cystoscopy.[ citation needed ]
Treatment depends on the type of neurogenic bladder and other medical problems. Treatment strategies include catheterization, medications, surgeries or other procedures. The goals of treatment focus on preserving the structure and function of the upper urinary tract, and on improving the quality of life for patients with neurogenic bladder. [2]
The first-line therapy for most patients is an anticholinergic medication. These are used for patients with over-active bladder muscles, who have lost the ability to hold their urine in. [2] Oxybutynin is a common anti-cholinergic medication used to reduce bladder contractions by blocking M3 muscarinic receptors in the detrusor muscle. [7] [2] Its use is limited by side effects such as dry mouth, constipation and decreased sweating. Patients must also be monitored for newly-developed difficulty emptying the bladder, which may result from excessive effects of the drug. [2] Tolterodine is a longer acting anticholinergic that may have fewer side effects. [9]
For urinary retention, cholinergics (muscarinic agonists) like bethanechol can improve the squeezing ability of the bladder. Alpha blockers can also reduce outlet resistance and allow complete emptying if there is adequate bladder muscle function. [9]
Use of a catheter is a standard approach for patients with difficulty voiding (emptying) the bladder. [2] For most patients, this can be accomplished with intermittent catherization which involves no surgery or permanently attached appliances. Intermittent catheterization involves using straight catheters (which are usually disposable or single-use products) several times a day to empty the bladder. [8] This can be done independently or with assistance. For people who are unable to use disposable straight catheters, a Foley catheter allows continuous drainage of urine into a sterile drainage bag that is worn by the patient, but such catheters are associated with higher rates of complications. [7]
Catheters are preferred over externally-applied pressure (such as with hands) or straining of the abdomen, even when these methods succeed in completely emptying the bladder. Those techniques can elevate the pressure inside the detrusor muscle of the bladder and cause additional bladder dysfunction, or even rupture the bladder. [2]
Botulinum toxin (Botox) can be used through two different approaches. For spastic neurogenic bladder, the bladder muscle (detrusor) can be injected which will cause it to be flaccid for 6–9 months. This prevents high bladder pressures and intermittent catherization must be used during this time. [9]
Botox can also be injected into the external sphincter to paralyze a spastic sphincter in patients with detrusor sphincter dyssynergia. [11]
There are various strategies to alter the interaction between the nerves and muscles of the bladder, including nonsurgical therapies (transurethral electrical bladder stimulation), minimally invasive procedures (sacral neuromodulation pacemaker), and operative (reconfiguration of sacral nerve root anatomy). [9]
Surgical interventions may be pursued if medical approaches have been maximized. Surgical options depend on the type of dysfunction observed on urodynamic testing, and may include:
The overall prevalence of neurogenic bladder is limited due to the broad range of conditions that can lead to urinary dysfunction. Neurogenic bladder is common with spinal cord injury and multiple sclerosis. [11] Rates of some type of urinary dysfunction surpass 80% one year after spinal cord injury. [7] Among patients with multiple sclerosis, 20–25% will develop neurogenic bladder although the type and severity bladder dysfunction is variable. [11]
In the United States, 40-90% of patients with multiple sclerosis, 37-72% of patients with Parkinsonism, and 15% of patients with stroke have neurogenic bladder. Dysfunction of the bladder is also frequently seen in patients with Spina Bifida, which affects 1 in 1000 births in the United States. It has been documented that about 61% of patients with Spina Bifida have some form of urinary incontinence. Around 70-80% of patients with spinal cord injury have degrees of bladder dysfunction. [26]
The burden of neurogenic bladder dysfunction on individuals and health care systems is substantial, but the actual costs of care are less understood. [1] [27] A recent systematic review of the literature assessed the global costs associated with the current state of care for neurogenic bladder and found that the annual costs of routine care can range from $2,039.69 to $12,219.07, with lifetime costs reaching up to $112,774 when complications are considered. [1] Catheters and absorbent aids are among the costliest categories of expenditure during routine care. [1] More invasive and reconstructive treatments were found to be even more costly, with costs ranging from $18,057 to $55,873. [1]
Urology, also known as genitourinary surgery, is the branch of medicine that focuses on surgical and medical diseases of the urinary-tract system and the reproductive organs. Organs under the domain of urology include the kidneys, adrenal glands, ureters, urinary bladder, urethra, and the male reproductive organs.
Urinary incontinence (UI), also known as involuntary urination, is any uncontrolled leakage of urine. It is a common and distressing problem, which may have a large impact on quality of life. It has been identified as an important issue in geriatric health care. The term enuresis is often used to refer to urinary incontinence primarily in children, such as nocturnal enuresis. UI is an example of a stigmatized medical condition, which creates barriers to successful management and makes the problem worse. People may be too embarrassed to seek medical help, and attempt to self-manage the symptom in secrecy from others.
Autonomic neuropathy is a form of polyneuropathy that affects the non-voluntary, non-sensory nervous system, affecting mostly the internal organs such as the bladder muscles, the cardiovascular system, the digestive tract, and the genital organs. These nerves are not under a person's conscious control and function automatically. Autonomic nerve fibers form large collections in the thorax, abdomen, and pelvis outside the spinal cord. They have connections with the spinal cord and ultimately the brain, however. Most commonly autonomic neuropathy is seen in persons with long-standing diabetes mellitus type 1 and 2. In most—but not all—cases, autonomic neuropathy occurs alongside other forms of neuropathy, such as sensory neuropathy.
Urinary retention is an inability to completely empty the bladder. Onset can be sudden or gradual. When of sudden onset, symptoms include an inability to urinate and lower abdominal pain. When of gradual onset, symptoms may include loss of bladder control, mild lower abdominal pain, and a weak urine stream. Those with long-term problems are at risk of urinary tract infections.
Transurethral resection of the prostate is a urological operation. It is used to treat benign prostatic hyperplasia (BPH). As the name indicates, it is performed by visualising the prostate through the urethra and removing tissue by electrocautery or sharp dissection. It has been the standard treatment for BPH for many years, but recently alternative, minimally invasive techniques have become available. This procedure is done with spinal or general anaesthetic. A triple lumen catheter is inserted through the urethra to irrigate and drain the bladder after the surgical procedure is complete. The outcome is considered excellent for 80–90% of BPH patients. The procedure carries minimal risk for erectile dysfunction, moderate risk for bleeding, and a large risk for retrograde ejaculation.
Prostatectomy is the surgical removal of all or part of the prostate gland. This operation is done for benign conditions that cause urinary retention, as well as for prostate cancer and for other cancers of the pelvis.
The Mitrofanoff procedure, also known as the Mitrofanoff appendicovesicostomy, is a surgical procedure in which the appendix is used to create a conduit, or channel, between the skin surface and the urinary bladder. The small opening on the skin surface, or the stoma, is typically located either in the navel or nearby the navel on the right lower side of the abdomen. Originally developed by Professor Paul Mitrofanoff in 1980, the procedure represents an alternative to urethral catheterization and is sometimes used by people with urethral damage or by those with severe autonomic dysreflexia. An intermittent catheter, or a catheter that is inserted and then removed after use, is typically passed through the channel every 3–4 hours and the urine is drained into a toilet or a bottle. As the bladder fills, rising pressure compresses the channel against the bladder wall, creating a one-way valve that prevents leakage of urine between catheterizations.
Stress incontinence, also known as stress urinary incontinence (SUI) or effort incontinence is a form of urinary incontinence. It is due to inadequate closure of the bladder outlet by the urethral sphincter.
Solifenacin, sold as the brand name Vesicare among others, is a medicine used to treat overactive bladder and neurogenic detrusor overactivity (NDO). It may help with incontinence, urinary frequency, and urinary urgency.
Bladder sphincter dyssynergia is a consequence of a neurological pathology such as spinal injury or multiple sclerosis which disrupts central nervous system regulation of the micturition (urination) reflex resulting in dyscoordination of the detrusor muscles of the bladder and the male or female external urethral sphincter muscles. In normal lower urinary tract function, these two separate muscle structures act in synergistic coordination. But in this neurogenic disorder, the urethral sphincter muscle, instead of relaxing completely during voiding, dyssynergically contracts causing the flow to be interrupted and the bladder pressure to rise.
The detrusor muscle, also detrusor urinae muscle, muscularis propria of the urinary bladder and muscularis propria, is smooth muscle found in the wall of the bladder. The detrusor muscle remains relaxed to allow the bladder to store urine, and contracts during urination to release urine. Related are the urethral sphincter muscles which envelop the urethra to control the flow of urine when they contract.
Overactive bladder (OAB) is a common condition where there is a frequent feeling of needing to urinate to a degree that it negatively affects a person's life. The frequent need to urinate may occur during the day, at night, or both. Loss of bladder control may occur with this condition. This condition is also sometimes characterized by a sudden and involuntary contraction of the bladder muscles, in response to excitement or anticipation. This in turn leads to a frequent and urgent need to urinate.
The urethral sphincters are two muscles used to control the exit of urine in the urinary bladder through the urethra. The two muscles are either the male or female external urethral sphincter and the internal urethral sphincter. When either of these muscles contracts, the urethra is sealed shut.
Sacral nerve stimulation, also termed sacral neuromodulation, is a type of medical electrical stimulation therapy.
Urodynamic testing or urodynamics is a study that assesses how the bladder and urethra are performing their job of storing and releasing urine. Urodynamic tests can help explain symptoms such as:
Overflow incontinence is a concept of urinary incontinence, characterized by the involuntary release of urine from an overfull urinary bladder, often in the absence of any urge to urinate. This condition occurs in people who have a blockage of the bladder outlet, or when the muscle that expels urine from the bladder is too weak to empty the bladder normally. Overflow incontinence may also be a side effect of certain medications.
Dyssynergia is any disturbance of muscular coordination, resulting in uncoordinated and abrupt movements. This is also an aspect of ataxia. It is typical for dyssynergic patients to split a movement into several smaller movements. Types of dyssynergia include Ramsay Hunt syndrome type 1, bladder sphincter dyssynergia, and anal sphincter dyssynergia.
An artificial urinary sphincter (AUS) is an implanted device to treat moderate to severe stress urinary incontinence, most commonly in men. The AUS is designed to supplement the function of the natural urinary sphincter that restricts urine flow out of the bladder.
A lumbar anterior root stimulator is a type of neuroprosthesis used in patients with a spinal cord injury or to treat some forms of chronic spinal pain. More specifically, the root stimulator can be used in patients who have lost proper bowel function due to damaged neurons related to gastrointestinal control and potentially allow paraplegics to exercise otherwise paralyzed leg muscles.
Neurogenic bowel dysfunction (NBD) is the inability to control defecation due to a deterioration of or injury to the nervous system, resulting in faecal incontinence or constipation. It is common in people with spinal cord injury (SCI), multiple sclerosis (MS) or spina bifida.