Doctor’s Passport

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Educational draft · awaiting clinical reviewUse Rapid for revision, not patient-care decisions. Check current national and local guidance and the BNF or BNFC before acting.
Rapid

Choosing the right imaging test

Essential points for quick revision.

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Time-critical diagnostic decision

When delay threatens life, limb, or immediate treatment, escalate directly to the relevant imaging team.

Action: Stabilise concurrently, state the decision deadline and suspected emergency, and agree the fastest adequate protocol.

Synopsis

Choose an examination that answers a defined clinical question, can alter management, and balances diagnostic yield against patient-specific harms and practical constraints.

  • Begin with one explicit clinical question and the management decision the result could change.
  • Review relevant previous imaging and reports before exposing the patient or duplicating an examination.
  • Match modality, anatomical coverage, contrast phase, urgency, and patient factors to that question.

Key red flags

Physiological instability or rapidly evolving neurology makes routine booking unsafe and demands immediate escalation.

A negative examination with limited sensitivity must not overrule persistent high clinical suspicion.

Unexpected contrast, pregnancy, renal, infection-control, or implanted-device issues require protocol review before acquisition.

Urgency mismatch

A clinically correct test scheduled too late may be the wrong test for the current decision and should trigger direct discussion.

Reasoning priorities

01
Clinical question and examination

Define the diagnosis or complication being tested.

A vague request produces a poorly targeted study; include the decision the result will change.

Worked reasoning

Worked caseStable focal abdominal pain

A stable adult has recurrent focal pain without shock or peritonism.

  1. Context: define whether the working question concerns gallstones, inflammation, obstruction, a mass, or another process.
  2. Reasoning: review examination, laboratory results and prior imaging, then compare ultrasound and CT performance for that question.
  3. Outcome: agree the study and protocol that can change management while avoiding redundant or poorly targeted phases.
  4. Verification: read the report, check whether it answered the question, and reassess if symptoms and imaging remain discordant.
Emergency routeEscalate a time-critical request

The diagnosis will alter immediate treatment and routine scheduling creates unsafe delay.

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Sources and review status3 sources · checked 13 Sept 2026 · clinical review pending
Sources

Sources and review status

National guidance is shown before implementation-dependent detail. Apply principles in context and verify current guidance when a decision affects care. Source check completed 13 Sept 2026; clinical approval remains outstanding.

Authoring stateRapid draftClinical stateAwaiting reviewJurisdictionUnited Kingdom