SCI Forum Report
Advances in Treatment of Urologic Conditions in the SCI Patient
Presented on November 14, 2006, by Elizabeth A. Miller, MD, Assistant Professor, Department of Urology, University of Washington. Read the summary report or watch the video from this page.
Please note: In order to continue offering videos of our SCI Forums, we need to show our funding sources that consumers are watching and benefiting from them. After watching the video, please complete our two-minute survey. Thank you!
(Mac users: to watch the video, you may have to download a program, which you can find at the following site: Microsoft Windows Media Components for QuickTime.)
-
Click here to view streaming video (50 minutes)
(This video contains captioning. To turn captions off, press "Ctrl+Shift+C" or follow the instructions on your Windows Media player.)
For a complete list of our videos, click here.
Summary Report
ANATOMY & DIAGNOSIS
"The neuroanatomy of the lower urinary tract is extremely complex,” said Elizabeth Miller, MD UW Assistant Professor of Urology. It consists of a great many nerve roots that branch off the spinal cord and come together in a network of neural pathways that govern the coordinated system of urination.
“But urologists like to simplify things, because we’re essentially glorified plumbers,” Miller joked. At the most basic level, our urinary system is a simple cycle of storage and voiding (urinating). When the bladder becomes full, nerve endings in the bladder wall send a message to the brain via the spinal cord. To void, the brain sends a message back to the bladder to contract (squeeze) the detrusor muscles (the muscles that make up the bladder wall) and relax the sphincter (a muscle that opens and closes) to release urine. After SCI, the neural pathways controlling this cycle no longer function normally.
“The recurrent theme in neurourology is not only to enhance quality of life for the patient, but to minimize bladder infections and protect the kidneys,” Miller stated. “And actually, the most important thing is to protect the kidneys.”
A urologic evaluation of an SCI patient includes a neurologic exam of the genitourinary system, focusing on the lower abdomen and genitalia; urinalyses and urine cultures; serum creatinine test to see how well the kidneys are functioning; and ultrasound or CT imaging of the kidneys and bladder.
“I like to do some kind of imaging pretty regularly in the first couple of years after injury because people are more prone to develop kidney and bladder stones in those early years,” Miller noted. Once she knows the kidney and bladder are stable, she does imaging every year or two.
“One of the most important components of the neurourology exam is the multichannel video urodynamic study,” she continued. “It sounds fancy and mysterious but it’s actually fairly simple.” Bladder, abdominal, and external sphincter pressures and activity are measured during filling and emptying of the bladder. X-rays are taken of the bladder during the study. This test shows, on both EMG tracings and on video, the activity of the abdomen, detrusor (bladder muscle), and urethra during bladder emptying.
Miller insists that standard single channel urodynamic studies without video cannot accurately diagnose the SCI patient. “A neurogenic patient needs video and multichannel,” she asserted. “Otherwise you won’t get all the information you need.”
UROLOGIC CONDITIONS & INJURY LEVEL
Different kinds of injuries result in different kinds of urinary dysfunction, Miller said, “and even though there are multiple levels of injury, we can classify them into two categories.”
Suprasacral injuries
These include all injuries above the sacral level of the spinal cord (includes lumbar, thoracic and cervical lesions). Most individuals fall into this category, and the most common condition is an overactive bladder.
- Detrusor hyperreflexia: involuntary contraction of the bladder, usually causing incontinence. “This is a storage problem,” Miller said. “The patient cannot hold his or her urine.”
- Detrusor external sphincter dyssynergia (DESD): Similar to hyperreflexia, but the external sphincter contracts at the same time the bladder is contracting so the bladder can’t empty. “This causes fairly dangerous conditions—high pressure bladder, autonomic dysreflexia (AD), bladder stones, recurrent urinary tract infections (UTIs)— all of which can ultimately result in renal damage,” Miller warned. “DESD needs to be diagnosed quickly and managed appropriately to avoid renal damage.”
- Detrusor internal sphincter dyssynergia (DISD): In this case, the internal sphincter, or the bladder neck, contracts at the same time the bladder is contracting. Like DESD, DISD results in high pressure bladder and renal damage.
Sacral injuries
These are injuries that involve the lowest part of the spinal cord. These injuries usually result in underactivity of the bladder.
- Areflexia: the bladder cannot contract, so the bladder cannot empty. “This is a voiding problem,” Miller said. “The bladder will fill and the pressure will rise to a dangerously high level.”
- Urethral deficiency: the urethral sphincter is weak and cannot keep urine from leaking out of the bladder. “This is a storage problem and can be very severe, to the point where the patient is always incontinent, or it can be very mild, to the point where only at certain volumes the patient begins to leak urine,” Miller explained. “Even though it doesn’t cause a dangerous situation in the bladder, it can be a health problem. Sitting in urine all the time can cause skin breakdown. And it’s a huge quality of life issue, so we take urethral deficiency very seriously.”
TREATMENTS
The management of neurogenic bladder problems will depend both on the diagnosis and on individual patient factors. For example, clean intermittent catheterization (CIC)— in which a catheter is inserted through the urethra into the bladder— is the preferred method for emptying the bladder in SCI patients, but individuals with limited upper extremity (arm and hand) function are often unable to do it themselves. CIC is also much harder for women to perform than men.
Treatments can be categorized by whether they address either a storage (holding urine) problem or a voiding (emptying urine) problem.
Storage problems
The bladder cannot store urine adequately, causing incontinence (leakage).
Detrusor hyperreflexia: the bladder muscle (detrusor) is contracting involuntarily, causing incontinence.
- Pharmacologic treatment: Antimuscarinic drugs (Ditropan, Detrol, Oxytrol patch, Enablex, Sanctura, Vesicare) reduce frequency and severity of incontinence episodes and increase voided volumes in 30-50% of cases. Common side effects are dry mouth, dry eyes, and constipation.
- Bladder injection of Botulinum Toxin A (Botox): When medications are ineffective, Botox may be considered. “This is a fairly new therapy,” Miller noted, “and we’ve found good success.” It is a minor surgical procedure (15 minutes), and patients go home the next day, but it needs to be repeated every six to nine months. This is a choice for patients who are comfortable performing intermittent catheterization or have indwelling Foley catheters. (Currently, Botox is not approved by the FDA for use treating bladder conditions.)
- Bladder augmentation: “When the more conservative measures fail, we go to what we call the ‘big guns,’” Miller said. This surgical procedure uses a segment of the bowel to reconstruct a larger bladder. It is a major surgery requiring a 7-10 day hospital stay.
Urethral deficiency: the urethra is weak and cannot keep urine from leaking out.
- Bladder outlet surgeries: Bladder neck closure, which involves disconnecting the bladder from the urethra and rechanneling urine to an outlet on the abdomen that can be catheterized; sling surgery, to compress the urethra; or artificial urinary sphincter, which keeps the urethra closed until the patient opens it using an implanted pump device.
Voiding problems
The patient cannot empty his or her bladder, causing increased bladder pressure and potential kidney damage.
Detrusor sphincter dyssynergia (DESD & DISD) and areflexia.
- Clean intermittent catheterization (CIC): Always the best management if the patient is able to do it.
- Urethral catheter: the catheter tube is inserted through the urethra and remains there, so the bladder drains constantly. Long-term use is not recommended due to risk of urethral erosion and recurrent UTIs.
- Suprapubic catheter: A surgical procedure that allows the patient to have a bladder catheter pass through an opening in the lower abdomen. “It brings the catheter away from a very dirty area—the perineum—up to a cleaner area and makes catheterizing very easy, particularly for women,” Miller said.
- Condom catheter and sphincterotomy (men only): Irreversible surgery in which the sphincter is cut so the urine passively drains into an external device (condom catheter) worn on the penis. Newer, non-surgical and reversible methods of accomplishing the same result include inserting a stent to keep the urethra open or injecting Botox into the sphincter.
- Urinary diversions: Usually done when bladder management does not lower bladder pressure enough to keep the kidneys safe. These are major surgeries in which a segment of the bowel—either colon, small bowel, or stomach—is sewn to the bladder to increase volume or allow urine to flow out of the body through a stoma.
Frequent UTIs
- “UTIs are a big problem for anyone who has an indwelling catheter or who needs to pass a catheter to empty the bladder, which is most SCI patients,” Miller said.
- Frequent UTIs (more than three per year, according to Miller) often require stronger antibiotics each time, leading to a situation in which the only option is IV antibiotics.
- Miller insists that only symptomatic infections should be treated. “Don’t let anyone run a culture on you unless you’re having symptoms,” she cautioned. An SCI patient’s urine culture will always show bacteria due to the constant use of catheters, but bacteria alone does not qualify as a UTI. Unnecessary use of antibiotics increases the risk of developing drug-resistant UTIs and should be avoided.
- To reduce the frequency of UTIs:
- Change indwelling catheters at least every four weeks, more often if necessary.
- For those using CIC, consider using single-use catheters if you are having frequent infections.
- Irrigate the bladder daily with 60-120cc of normal saline, “which disrupts all the mucous that can build up in the bladder,” Miller explained.
- Take Vitamin C (500mg twice daily), cranberry (800mg twice daily) or methanamine (Hiprex). While study results have been contradictory, Miller recommends these treatments based on the success she has seen in her own patients, and they can’t do any harm.
References
1. Riccabona M, et al. Botulinum-A toxin injection into the detrusor: a safe alternative in the treatment of children with myelomeningocele with detrusor hyperreflexia. J Urol 2004 Feb;171 (2 Pt 1):845-8.
2. Chartier-Kastler EJ, et al. A urethral stent for the treatment of detrusor-striated sphincter dyssynergia. BJU Int. 2000 Jul;86(1):52-7.