516 CHAPTER 13 Neuropathic bladder

Catheters and sheaths and the neuropathic patient

Many patients manage their bladders by intermittent catheterization (IC) done by themselves (intermittent self-catheterization, ISC) or by a caregiver if their hand function is inadequate, as is the case with most tetraplegics. Many others manage their bladders with an indwelling catheter (urethral or suprapubic). Both methods can be effective for managing incontinence, recurrent UTIs, and bladder outlet obstruction causing hydronephrosis.

Intermittent catheterization

IC requires adequate hand function. The technique is a clean one (simple handwashing prior to catheterization) rather than a sterile one.

Gel-coated catheters become slippery when in contact with water, thus providing lubrication. IC is usually done every 3–4 hours.

Problems

•Recurrent UTIs

•Recurrent incontinence: check technique (adequate drainage of last few drops of urine). Suggest increasing frequency of ISC to minimize volume of urine in the bladder (reduces bacterial colonization and minimizes bladder pressure). If incontinence persists, consider intravesical botulinum toxin.

Long-term catheterization

Some patients and clinicians prefer the convenience of a long-term catheter. Others regard it properly as a last resort when other methods of bladder drainage have failed.

The suprapubic route (suprapubic catheter [SPC]) is preferred over the urethral because of pressure necrosis of the ventral surface of the distal penile urethra in men (acquired hypospadias—“kippering” of the penis) and pressure necrosis of the bladder neck in women, which becomes so wide that urine leaks around the catheter (“patulous” urethra) or frequent expulsion of the catheter occurs with the balloon inflated.

Problems and complications of long-term catheters

Recurrent UTIs: colonization with bacteria provides a potential source of recurrent infection.

Catheter blockages are common due to encrustation of the lumen of the catheter with bacterial biofilm. Proteus mirabilis, Morganella, and Providencia species secrete a polysaccharide matrix. Within this, ureaseproducing bacteria generate ammonia from nitrogen in urine, raising the urine pH and precipitating magnesium and calcium phosphate crystals. The matrix–crystal complex blocks the catheter.

518 CHAPTER 13 Neuropathic bladder

Management of incontinence in the neuropathic patient

Causes

These include high-pressure bladder (detrusor hyperreflexia, reduced bladder compliance); sphincter weakness; UTI; bladder stones; and rarely, bladder cancer (ask about UTI symptoms and hematuria).

Hyperreflexic peripheral reflexes suggest that the bladder may be hyperreflexic (increased ankle jerk reflexes, S1–2 and a positive bulbocavernosus reflex indicating an intact sacral reflex arc—i.e., S2–4 intact).

Absent peripheral reflexes suggest that the bladder and sphincter may be areflexic (i.e., sphincter is unable to generate pressures adequate for maintaining continence).

Initial investigations

These include urine culture (for infection); KUB X-ray for bladder stones; bladder and renal ultrasound for residual urine volume and to detect hydronephrosis; cytology and cystoscopy if bladder cancer is suspected.

Empirical treatment

Start with simple treatments. If the bladder residual volume is large, regular ISC may lower bladder pressure and achieve continence. Try an anticholinergic drug (see p. 511).

Many SCI patients are already doing ISC and simply increasing ISC frequency to every 3–4 hours may achieve continence. ISC more frequently than every 3 hours is usually impractical, particularly for paraplegic women who usually have to transfer from their wheelchair onto a toilet and then back onto their wheelchair. See Table 13.1.

Management of failed empirical treatment

This is determined by cystometrogram, sphincter EMG, and VCUG to assess bladder and sphincter behavior.

Detrusor hyperreflexia or poor compliance

High-pressure sphincter (i.e., DSD)

Treating the high-pressure bladder is usually enough to achieve continence.

•Bladder treatments—intravesical botulinum toxin, detrusor myectomy (autoaugmentation), bladder augmentation (ileocystoplasty). All of these will usually require ISC for bladder emptying.

•Long-term suprapubic catheter

•Sacral deafferentation + ISC or Brindley implant (SARS—sacral anterior root stimulator)

Low-pressure sphincter

Treat the bladder first (as above). If bladder treatment alone fails, consider a urethral bulking agent, urethral sling procedure, or bladder neck closure in women (last resort) or an artificial urinary sphincter in either sex (Fig. 13.5).