Objectives
To guide military healthcare workers in the recognition and management of patients with urinary retention.
Scope
This guideline describes the management of patients with urinary retention in military settings from forward medical locations through to deployed hospital facilities.
There is a separate guideline for insertion of urinary catheters (link).
Definitive treatment (surgery) is not within the scope of this guideline but is covered in specialist guidance.
Audience
This guideline is intended for use by registered healthcare professionals fulfilling a general role in forward medical locations or in an emergency department in a deployed hospital setting.
Initial Assessment & Management
Urinary retention is defined as the inability to voluntarily void the bladder. It may be acute or chronic in onset.
Common signs and symptoms include:
- Inability to urinate despite urge
- Lower abdominal pain or discomfort
- Palpable suprapubic mass: a distended bladder is usually midline and dull to percussion.
- Dribbling or overflow incontinence
- Agitation or confusion (especially in elderly patients)
Always suspect urinary retention in trauma patients with pelvic, perineal, or spinal injuries.
Be aware that acute urinary retention can form part of the anticholinergic syndrome seen after exposure to certain CBRN incapacitating agents (such as BZ) or as a result of atropine administered as a CBRN countermeasures.
Definitive treatment of urinary retention depends on the underlying cause.
1. Conduct an initial primary survey and vital signs assessment.
Ensure full exposure and conduct a thorough primary survey, including vital signs.
Examine the suprapubic and genital regions.
Inspect the perineum and urethral meatus for bleeding or trauma.
Perform a digital rectal examination to assess prostate size (in males), anal tone and perineal sensation (especially if spinal injury or cauda equina syndrome are suspected). This should be performed after catheterisation and with patient consent and a chaperone present (if available).
In females, careful bi-manual pelvic examination with consent and a chaperone can be considered to assess for cystocele, pelvic malignancy or other anatomical abnormalities. However, the outcome of this examination may not affect immediate management so it may be appropriate to defer until a specialist assessment.
2. Perform bladder decompression using catheterisation to relieve acute painful urinary retention.
Confirm the diagnosis. This is usually clinical but if there is uncertainty, urinary retention can be confirmed with point of care ultrasound or bladder scanner (if available).
Insert a urinary catheter. See the Urinary Catheter Insertion Emergency Procedure CGO (link to follow) for details.
Record:
Time of catheterisation
Volume of saline inserted into the catheter balloon
The volume of urine drained 15mins after catheterisation (the retention volume)
Urine characteristics; colour, clarity, or frank haematuria.
Replacement of the patient’s foreskin (if present)
Details of catheter inserted (e.g. size/long-term or short term/lot number)
3. Investigations in forward locations
If available, perform urine dipstick at the time of catheterisation. If positive for nitrates or leukocytes, infection is probable and treatment should commence early with antibiotics (as per DMS antimicrobial guidelines). Formal urine culture should follow when facilities are available.
Point of care blood testing (if available) may be helpful to identify renal failure or electrolyte abnormalities related to urinary retention.
4. Treat the suspected underlying cause of urinary retention.
See accordion content below for details.
5. Observe for and treat complications
See accordion content below for details.
6. Evacuate to higher level of care.
All patients will need further investigation and treatment for the underlying cause and most will need a Trial Without Catheter (TWOC).
Advanced Assessment & Management
Ensure all measures outlined in Initial Management (above) are undertaken
Investigations in deployed hospital settings
- Bladder scan to measure pre-catheterisation volume +/- point of care ultrasound to assess bladder volume and structure.
- Urinalysis (dipstick, microscopy, and culture if infection suspected). Treat as per current DMS antimicrobial guidelines if positive for nitrates and/or leukocytes.
- Blood tests: renal function (U&Es), infection markers (FBC, CRP, ESR)
- CT abdomen and pelvis +/- contrast: should identify stones causing obstruction, associated hydronephrosis, masses in ureter/pelvis/bladder.
- If available, urethrogram (contrast X-ray) to evaluate urethral injuries, strictures, or fistulae, and renal tract ultrasound if any renal impairment identified on blood tests.
- MRI is unlikely to be available in the deployed setting so evacuation to a higher level of care for imaging will be required if a spinal cord lesion is suspected.
Refer to specialty specific guidance for definitive management of urinary retention (e.g. urological surgery) in deployed hospital settings.
Prolonged Casualty Care
Maintain catheter drainage and daily meatal hygiene.
Secure catheter to leg or bed to prevent dislodgement.
Use aseptic technique when cleaning or changing catheter bags.
Monitor urine output; if unstable, record hourly and chart fluid balance.
Observe for complications of urinary retention and catheterisation (see accordion content).
Short-term catheters may remain in place for up to 28 days but should be removed as soon as clinically unnecessary. If use is expected beyond 14 days, exchange for a long-term catheter.
Paediatric Considerations
Urinary retention in children is rare, usually due to infection, constipation, trauma, or neurological causes. Management is similar to adults but ensure appropriate catheter size (6–10 Fr for infants/small children).
