Method of bladder management

Trial of void and voiding

A trial of void (TOV) tests the bladder function, enabling medical staff to assess whether a catheter is necessary or whether it can be permanently removed.

Indicators that a TOV might be worthwhile include:

  • Favourable signs for voiding are a rectal examination with normal sensation in S4/S5 dermatomes and the ability to voluntarily contact and relax the anal sphincter (see – Anorectal examination).
  • The presence of bladder sensation, as well as a possible desire to urinate.

Potential barriers against a TOV:

  • A suspected or confirmed urinary tract infection (UTI) will delay a TOV.
  • The risk of autonomic dysreflexia. Consider education on autonomic dysreflexia and management for those with a neurological level of T6 or above.
  • Screening for constipation. Constipation can increase the frequency of voiding and cause bladder outlet obstruction.
  • Assess functional skills, such as mobility and independence with dressing.
  • Cognition or memory issues.
  • Medication review. For example, anticholinergics may impair the ability to void.
  • Relevant medical and surgical history e.g. prostatic enlargement and pelvic floor issues.

TOV Process

Abbreviations

PVR: post void residual
TOV: trial of void
ICSC: intermittent clean self-catheterisation

Bladder Scanning:

  • It is important to measure the post-void residual immediately after voiding for accuracy, as the renal output can be 1-14ml per minute.
  • Use ample gel on the probe and scan around two finger widths above the symphysis pubis, direct probe towards the bladder.
  • Make sure the appropriate settings are selected.

Examination of the Bladder via Ultrasound at U of SC School of Medicine

Be aware of:

  • Trigger volumes: some people may require a larger volume of urine to trigger a void. It is best to avoid over-distention of the bladder. The maximum volume of urine in a bladder should be 500ml. The bladder has also been on a continuous drain with an indwelling catheter, and may not be able to effectively hold large volumes of urine.
  • Over-distension of the bladder. This may reduce blood flow to the bladder wall, making it more susceptible to infection from bacterial growth. Overstretching the bladder. This can cause long-term damage to the muscle and nerves.
  • Ureteric reflux can occur with an upper motor neurone (UMN) bladder. This can sometimes be a ‘silent’ issue.
  • Deferring the trial of void or doing intermittent catheters won’t delay recovery of bladder function. Intermittent catheterisation will help mimic normal bladder function with filling and emptying. This may also assist with planning for future attempts with TOV, if there is an improvement in sensory feedback and control.

References

Hsieh JTC, McIntyre A, Loh E, Ethans K, Mehta S, Wolfe D, Teasell R. (2019). Epidemiology of Pediatric Spinal Cord Injury. In Eng JJ, Teasell RW, Miller WC, Wolfe DL, Townson AF, Hsieh JTC, Connolly SJ, Noonan VK, Loh E, Sproule S, McIntyre A, Querée M, editors. Spinal Cord Injury Rehabilitation Evidence. Version 7.0. Vancouver: p 1-274 bladder-management_final_v7-1.pdf

State of Queensland (Queensland Health) ‘Preventing CAUTI – Catheter-Associated Urinary Tract Infection eLearning Program’