Urologic Management of the Spinal Cord Injured Patient



- See:
      - Autonomic Dysfunction:
      - Management of the Spine Injured Patient:
      - UTI:

- Discussion:
    - it is rare to find a patient who has a single bladder dysfunction, nevertheless, somem generalizations can be made;
    - traumatic cord lesions above T12 usually result in a reflex neurogenic bladder (upper motor neuron) and lesions below that level, in
         mixed or lower motor neuron lesion;

- Acute Phase of Spinal Shock: (see spinal shock)
    - this variable period, which is manifested by a hypotonic, paresthetic areflexic bladder, usually lasts approximately 6-12 weeks;
         - more rapid recovery occurs with incomplete lesions;
    - treatment goal in the acute phase is simply the prevention of UTI and urosepsis;
    - intermittent sterile catheterization, small caliber (12-14 Fr) catheter is used every 4-6 hours to maintain a bladder volume < 500 ml;
         - in the chronic phase bladder volumes should be < 100 ml;
         - consider ascorbic acid and mandelamine
         - when used institutionally, intermittent catheterization requires strict sterile techniques, whereas outpatient intermittent
              catheterization only requires a clean technique;

- Failure of Bladder Emptying:
    - failure to maintain continence in patients with neurogenic bladder dysfunction may be due to uninhibited bladder contractions, decreased outlet resistance, overflow incontinence or iatrogenic causes related to pharmacologic or surgical intervention;
    - lower motor neuron bladder results in hypotonic detrussor function and failure to generate enough intravesical pressure for adequate emptying;
    - increased outlet resistance due to bladder neck hypertrophy, prostatic obstruction or increased resistance of external sphincter leads to
         incomplete emptying;
         - methods available to increase the intravesical pressure include external compression (Crede) and increased intra-abdominal pressure;
         - these methods require a low outet resistance and a patient who is physically able to perform these maneuvers;
         - application is usually limited to lower motor neuron bladders;
    - attempt to reduce bladder neck and external sphincter resistance using medications have met with some success;
    - alpha adrenergic agents (dibenzyline) and skeletal muscle relaxants (ie, diazepam, baclofen, dantrolene) have been used alone or in
         combination;
    - if increased outlet resistance is secondary to physical obstruction or fails to respond to pharmacologic methods, surgery may be indicated;
    - unless adequate drainage can be maintained, a neurologic bladder may become very large;

- Treatment:
     - persistent outlet obstruction can eventually decrease renal function and predispose to urinary infection;
     - consequently these patients are often left with urinary catheters;
     - vesical calcifications are not uncommon in paraplegic patients because stone formation is favored by urinary stasis;
     - in alkaline urine, calcification is favored and may even occur around foreign body;
          - any sold materal may become nidus for calcium salt encrustation;
     - oxbutynin chloride (ditropan):
          - may be effective in patients with upper motor neuron lesions;

- Bethanechol
    - parasympathomimetic agent that has a direct stimulating effect on the detrussor, causing increased intravesicular pressure;
    - in doses of 5-10 mg SC or in oral doses of 50 mg or more, it may be of use in treating some pts with neurogenic bladder dysfunction;
    - this med may cause sphincter detrussor dyssynergia;
    - impairment of bladder storage function:
         - pharmacologic manipulation using agents to competitviely block acetyl- choline receptors have been tried;
         - these agents, having an atropine like effect, act primarily at post ganglionic autonomic effector sites;
         - prophantheline bromide (Pro banthine) has been used to block unihibited contractions;
              - 15 mg PO q4-6 hrs in the adult;
              - side effects include dry mouth, blurred vision, constipation;

- Management of Post Void Residual:
    - in patients who void by reflex, the volume of residual urine after voiding should be less than 100 ml to confirm adequate emptying;
    - high-pressure reflex voiding can sometimes be improved by combination of alpha-adrenergic blockers and antispasticity agents to relax
         internal and external sphincters or by surgery;
    - intermittent catheterization, however, can be used in men or women and in patients with flaccid or reflex bladders


Undetected genito-urinary dysfunction in vertebral fractures.



Original Text by Clifford R. Wheeless, III, MD.

Last updated by Data Trace Staff on Thursday, May 24, 2012 10:48 am