Urinary symptoms are common in nursing homes and can be complicated by frailty, reduced mobility, constipation, cognitive impairment, neurological disease, and medicines that affect bladder function. A portable ultrasound bladder scanner provides a quick, non-invasive estimate of bladder volume and post-void residual (PVR) urine at the bedside. Used correctly, bladder scanning strengthens elderly bladder assessment, supports continence care plans, and can help avoid unnecessary catheterisation and its complications.
This article summarises bladder scanner nursing home best practices for trained healthcare staff. Always follow local policies and the device manufacturer’s instructions for use (IFU), and seek medical review when results do not match the clinical picture.
Key takeaways
Scan for a clear indication and document the clinical question.
Measure PVR soon after voiding and repeat if readings are inconsistent.
Interpret results in context; persistent large PVR (often >200-300 mL) warrants review.
Escalate urgently if acute retention is suspected.
Clean and low-level disinfect external probes between residents.
Maintain competency-based training and consistent documentation.
Why bladder scanning matters in nursing homes
Bladder scanning is most useful when it answers a specific clinical question within a structured assessment. In a nursing home it can help clinicians:
Identify urinary retention (acute or chronic) and overflow incontinence.
Quantify PVR after voiding to support observation, toileting support, medication review, or escalation.
Support catheter decisions (for example, trials without catheter) and troubleshoot suspected catheter blockage.
Reduce avoidable catheterisation, which is a key CAUTI prevention strategy.
Bladder scanning is not a test for urinary tract infection (UTI). It should be used to assess bladder emptying, not to diagnose infection.
Clinical indications for bladder scanning in a nursing home
Perform a nursing home bladder scan when there is a clear clinical indication and the result will change management. Common indications include:
Suspected acute retention (urgent): inability to pass urine, suprapubic pain/discomfort, visible distension, or rapid deterioration with lower abdominal discomfort.
Suspected chronic retention / overflow incontinence: frequent small voids or dribbling, sensation of incomplete emptying, weak/intermittent stream (where reported), or persistent wet pads despite toileting support.
PVR measurement in continence assessment: lower urinary tract symptoms where incomplete emptying is possible, including prior to starting or reviewing medicines that can worsen retention (for example, antimuscarinics) when this is part of your service protocol.
Trial without catheter (TWOC): monitor voiding and PVR after catheter removal using a predefined pathway and escalation thresholds.
Catheter troubleshooting: poor drainage or bypassing where a scan can help determine whether the bladder is distended.
Document the indication before scanning (what you are assessing and what you will do with the result).
Post-void residual in older adults: what it means
PVR is the volume of urine left in the bladder at the end of micturition. The International Continence Society notes there is no universally accepted cut-off for a “significant” PVR; interpretation must consider symptoms and the wider assessment. Persistently large PVR values (often discussed in the >200 to 300 mL range) may indicate marked bladder dysfunction and warrant clinical review.
Measure PVR as soon as practical after voiding to minimise normal refilling (for example, within 10 to 15 minutes, and ideally no later than 30 minutes if possible).
PVR interpretation guide (context-dependent)
Note: There is no universally accepted “significant PVR” threshold. Use this table as a practical guide and follow local policy and clinical judgement.
PVR (mL) | Possible interpretation | Examples of nursing home actions |
<100 | Usually low residual in many adults; interpret in context. | Continue holistic continence assessment. If symptoms persist, consider other causes and seek review as appropriate. |
100–200 | Borderline/mildly elevated in some cases; may be acceptable in some older adults. | Confirm timing and technique. Consider repeat measurement, bowel review, toileting support and medication review. |
200–300 | Often considered elevated; may indicate incomplete emptying or bladder dysfunction. | Re-scan for confirmation. Escalate for clinical review per protocol, especially if symptomatic or persistent. |
>300 or rising rapidly | Large residual; higher concern for significant retention/bladder dysfunction. | Escalate promptly. Follow local urgent assessment/catheter pathway if authorised and trained. |
Contraindications and common sources of error
Bladder scanning is safe for most residents, but results can be unreliable in certain situations.
Do not scan (or seek advice first) if:
Consent is not obtained (or capacity/best-interest requirements are not met).
There is non-intact skin, severe pain, or an open wound over the suprapubic area.
Pregnancy is known or suspected (follow local policy and device settings).
Use caution interpreting results if there is ascites/free abdominal fluid, large pelvic masses (for example, ovarian cysts), or altered anatomy, as scanners may misread other fluid collections as bladder volume. If results do not fit the clinical picture, repeat the scan, check settings/positioning, and escalate for review rather than acting on a single questionable reading.
Step-by-step technique: how to perform a high-quality bladder scan
Follow your organisation’s competency checklist and the device IFU. These steps reflect common NHS-style protocols.
Preparation
Explain the procedure, obtain consent, and maintain privacy and dignity.
Perform hand hygiene and prepare the scanner (battery, settings such as male/female; pregnancy mode if applicable).
Position the resident supine with head slightly raised. Expose the lower abdomen while preserving dignity.
Scanning technique
Apply sufficient ultrasound gel.
Palpate the pubic symphysis and place the probe midline about 3 finger widths (around 1 inch) above the pubic bone.
Angle slightly towards the coccyx and initiate the scan.
Review the image (if available) and repeat until you have consistent readings (for example, three similar measurements).
PVR measurement
If measuring PVR, scan as soon as practical after voiding.
Record the scan time, voiding time, symptoms, and measured volumes (including voided volume if collected during a voiding trial).
Aftercare
Remove gel, settle the resident, and clean/disinfect the probe and device surfaces according to IFU and local infection prevention policy.
Interpreting results and next steps: a practical clinical framework
Interpret bladder scan results alongside symptoms, abdominal examination, bowel status (constipation), fluid intake/output, recent catheter changes or removal, and medicines that may impair emptying.
Practical actions by result category (guide only)
Low volume / low PVR: continue broader continence assessment; consider other causes of symptoms (for example, dehydration, constipation, irritation, delirium).
Moderate PVR: confirm timing/technique, consider conservative measures (toileting posture/support, privacy, double voiding), address constipation, and request medication review if retention-promoting medicines are present.
Large or rising PVR / suspected retention: escalate promptly for clinical review. Follow local pathways for intermittent catheterisation or urgent catheterisation where staff are trained and authorised.
When to treat as urgent
If a resident cannot pass urine and has significant discomfort/distension or rapidly worsening symptoms, treat as suspected acute urinary retention and escalate urgently according to local emergency arrangements.
Using bladder scanning to support continence care and catheter reduction
Embed bladder scanning into a structured continence pathway to make elderly bladder assessment consistent and actionable:
- Use a bladder diary (often 3 days) to understand voiding patterns and triggers.
- For TWOC, define monitoring frequency and escalation thresholds in advance, and consider PVR trends across several voids rather than a single reading.
- For suspected catheter blockage or bypassing, use a scan to determine whether the bladder is distended and managed according to catheter policy.
Consistent, protocol-led scanning supports safer catheter decisions and can contribute to reducing CAUTI risk by avoiding unnecessary indwelling catheters.
Infection prevention: cleaning and reprocessing between residents
Even though the scan is non-invasive, the probe and scanner are shared patient-care equipment and must be reprocessed between residents.
- External probes used on intact skin generally require cleaning plus low-level disinfection between patients, following the manufacturer’s IFU.
- Remove gel and disinfect the probe head, cable, and high-touch device surfaces.
- Use approved, compatible disinfectant wipes and follow contact times.
- Store the scanner clean and dry, and report damage or faults promptly.
Training, documentation, and governance in nursing homes
Bladder scanning should be competency-based in nursing homes.
Training should cover: indications/contraindications and consent, correct probe placement and settings, PVR timing, interpretation in context (including the lack of a universal cut-off), escalation pathways, and infection prevention/device care.
Documentation should record: indication, voiding and scan times, volumes (pre-void/PVR as relevant), symptoms, actions taken, and confirmation that equipment was cleaned.
When introducing or updating a bladder scanner nursing home protocol, build in periodic audit of catheter use, documentation quality, and competency renewal to sustain safe practice.
