01OverviewDefinition, clinical context and the essential points that orientate the chapter.
Trauma imaging answers three sequential questions: is there an immediate clinical threat requiring treatment without imaging, is the patient physiologically suitable to leave the resuscitation area, and which acquisition will change management? This prevents both under-imaging and the equally dangerous reflex of scanning an unstable patient. The trauma leader integrates response to resuscitation, mechanism, examination and available source-control resources with radiology and surgical teams.
Whole-body CT is designed for rapid mapping of suspected multisystem blunt injury in adults who are stable enough or responding sufficiently. NICE specifies vertex-to-mid-thigh acquisition without repositioning; clinically required limb imaging follows. Local protocols determine contrast timing and whether arms remain down initially. The team accompanying the patient must be able to manage airway, chest, transfusion and sudden deterioration, with a rehearsed route from scanner to theatre or interventional radiology.
Selective imaging is safer when injury is isolated, the mechanism and examination are reliable, or radiation susceptibility is high. Children should not undergo routine adult-style whole-body CT: use clinical findings and senior paediatric radiology advice to choose regions and protocols. Penetrating injury is usually tract- and physiology-directed. In older or anticoagulated people, apparently low-energy mechanisms may warrant a lower threshold for head or spine imaging because examination and compensation are less reliable.
Bedside imaging is a decision aid during instability. A chest radiograph may support haemothorax or tube-position decisions; a pelvic radiograph can demonstrate ring disruption; eFAST can reveal pericardial or intraperitoneal fluid and pleural air. Each has important false negatives. Tension pneumothorax is treated clinically, and a negative eFAST does not clear the abdomen or retroperitoneum. Repeating a low-sensitivity test must not become a substitute for source control or definitive CT when appropriate.
Contrast planning matters. Arterial bleeding, blunt cerebrovascular injury, solid-organ trauma, urinary tract injury and bowel injury require different interpretation and sometimes phases. Communicate mechanism, wounds, physiology and suspected site to the radiologist. Do not delay urgent contrast-enhanced imaging solely to obtain a creatinine when the result is needed to treat a life-threatening injury. Record previous severe contrast reaction and prepare an alternative or emergency plan with radiology.
Pregnancy changes optimisation but not the principle that necessary diagnosis should proceed. Verify pregnancy when feasible without time-critical delay, shield only if it does not degrade the study, minimise repeated acquisitions and involve radiology or medical physics for dose questions. Ultrasound and MRI can avoid ionising radiation for suitable stable questions, but neither should replace a faster, more accurate CT when maternal haemorrhage, head injury or major thoracoabdominal injury is suspected.
The imaging process ends with action, not acquisition. A clinician should review critical images while the formal report is produced, communicate urgent findings directly and document the management consequence. Final reports and addenda must reach the responsible team after ward, hospital or specialty transfer. Incidental findings need a named owner, patient communication and follow-up route. If examination later conflicts with an earlier image, discuss re-review or additional imaging rather than treating the first report as immutable.
Key points
- Settle the destination during the primary survey: unstable non-responder to haemorrhage control, suitable responder to CT, and isolated stable injury to selective imaging.
- For adults with blunt major trauma and suspected multiple injuries, NICE recommends immediate whole-body CT from vertex to mid-thigh without repositioning during acquisition.
- Do not routinely use whole-body CT in children; image the body regions indicated by clinical assessment, using paediatric protocols and senior radiology input.
- Use chest or pelvic radiography and eFAST in an unstable patient only when the result will direct immediate intervention; negative bedside studies are not definitive exclusion tests.
- Plan intravenous contrast phase and any CT angiography with the radiologist from suspected vascular, organ and urinary injury rather than adding delayed phases indiscriminately.
- Pregnancy should prompt optimisation and documentation, not cancellation of necessary maternal imaging; maternal survival is the best immediate fetal intervention.
- Do not remove spinal protection or perform repeated limb movement merely to obtain images; secure tubes, drains, binder and monitoring before transfer.
- Review images and preliminary report promptly, then acknowledge the final report and assign ownership for every acute and incidental finding.
02AetiologyUnderlying causes, associations and risk factors, with why each one matters.
Multisystem blunt trauma
High-energy collisions, falls and crush mechanisms distribute injury across head, spine, trunk and limbs, making limited region-by-region imaging liable to miss occult damage.
Focused penetrating trauma
Stab and ballistic tracks often require targeted contrast imaging based on wounds and physiology rather than automatic blunt-trauma whole-body acquisition.
Low-energy high-risk trauma
Older age, frailty, osteoporosis and anticoagulation can produce important head, spine, chest or pelvic injury from mechanisms that initially appear minor.
03PathophysiologyThe causal sequence from the underlying abnormality to symptoms and harm.
- 1Occult anatomical injury
Deep cavities and retroperitoneal spaces accommodate blood or organ disruption without obvious external signs, so cross-sectional imaging can reveal otherwise silent threats.
- 2Physiological instability
Movement away from resuscitation during uncontrolled bleeding, airway failure or tension physiology can precipitate arrest before diagnostic information changes care.
- 3Contrast information
Arterial and portal-venous phases can distinguish active extravasation, vascular disruption and solid-organ injury, guiding embolisation, surgery or surveillance.
- 4Radiation susceptibility
Ionising radiation carries cumulative stochastic risk, particularly in children and fetal exposure, so acquisition should answer a defined clinical question without avoidable repeat studies.
04Clinical features and red flagsSymptoms, examination findings, patterns of presentation and time-critical warnings.
Persistent profound shock, active airway failure, clinical tension physiology or uncontrolled external bleeding requires immediate treatment and source control before conventional scanner transfer.
High-energy blunt mechanism with findings in several regions, reduced consciousness or unreliable examination supports rapid multisystem CT in a suitable adult responder.
A stable, reliable patient with convincing isolated injury and no concerning mechanism can undergo focused imaging rather than automatic whole-body exposure.
Pulse deficit, expanding haematoma, neurological signs, high-risk neck injury or active contrast loss indicates targeted CT angiography or direct vascular intervention depending on physiology.
Size, developmental examination and radiation sensitivity require senior review, weight-appropriate protocols and region-by-region justification rather than routine adult acquisition.
New pain, falling haemoglobin, ileus, neurological deficit or worsening physiology after negative imaging should trigger re-examination and radiology discussion for missed or evolving injury.
05InvestigationsWhat to request, why it matters and how to interpret it.
Read from the initial assessment onwards. Tests may run in parallel in urgent care; first-line, preferred, confirmatory, definitive and gold-standard labels appear only when the chapter explicitly states them.
- 01
Immediate whole-body CT in selected adultsFirst step - Why
- Define multisystem blunt injury in one coordinated acquisition.
- Interpretation and limitations
- Use vertex-to-mid-thigh CT without repositioning when multiple injuries are suspected and physiology allows; interpret active bleeding, organ injury, head and spinal findings together.
- 02
First-line selective radiographsFirst line - Why
- Evaluate a stable suspected isolated fracture or joint injury.
- Interpretation and limitations
- Obtain adequate orthogonal views with relevant adjacent joints; a technically poor or anatomically incomplete study cannot exclude injury suggested clinically.
- 03
eFAST - Why
- Look rapidly for pericardial, pleural and intraperitoneal findings during resuscitation.
- Interpretation and limitations
- A positive study may direct immediate care, but sensitivity varies with time, operator and injury site; negative results do not exclude significant haemorrhage.
- 04
CT angiography - Why
- Map suspected arterial injury and plan repair or embolisation.
- Interpretation and limitations
- Contrast extravasation, occlusion, pseudoaneurysm or intimal injury requires rapid specialist discussion; hard vascular signs with instability may justify direct operation.
- 05
MRI - Why
- Assess cord, ligament, occult bone or soft-tissue injury after initial stabilisation.
- Interpretation and limitations
- MRI provides detailed non-ionising tissue contrast but is slower, less accessible and unsafe with some devices; use when the answer changes specialist management.
- 06
Final-report review - Why
- Detect revised interpretation and incidental findings.
- Interpretation and limitations
- Compare the authorised report with preliminary decisions, document acknowledgment and assign follow-up; report addenda must cross specialty and hospital boundaries.
06Differential diagnosisRealistic alternatives and the features that help distinguish them.
Medical cause of collapse
Syncope, seizure, stroke, acute coronary syndrome or hypoglycaemia can cause trauma and may require targeted brain, cardiac or metabolic investigation alongside injury imaging.
Soft-tissue injury without fracture
Pain and functional loss may arise from ligament, tendon or muscle injury that plain radiography cannot show and later ultrasound or MRI may define.
Chronic imaging abnormality
Old fracture, degenerative change, vascular calcification and pre-existing spinal deformity can mimic acute injury unless compared with examination and prior studies.
Incidental disease
Tumour, aneurysm, infection or unrelated organ abnormality may appear on trauma CT and requires explicit communication without distracting from immediate injury treatment.
07ManagementImmediate care, first-line treatment, alternatives and escalation.
01TriageDecide stability before modalityFirst stepThe primary survey identifies possible major injury requiring imaging or immediate control.+
- 1Treat airway obstruction, tension pneumothorax and external catastrophic bleeding first, start blood resuscitation and assess response over time.
- 2For persistent non-response, use clinical and focused bedside findings to choose operative, endovascular or hybrid source control without routine CT delay.
- 3For a stable or sufficient responder, define whether injuries are multisystem or isolated and discuss acquisition and contrast with radiology.
- 4Secure airway devices, drains, access, monitoring, warming and escort capability before leaving the resuscitation area.
02AcquisitionPerform justified imaging efficientlyThe patient can safely undergo the chosen study and the clinical questions are explicit.+
- 1Use immediate vertex-to-mid-thigh whole-body CT for an appropriate adult with blunt suspected multiple injury, adding limb imaging according to clinical findings.
- 2Use targeted paediatric or isolated-region studies when whole-body imaging is not justified, with protocol adjustment for size and question.
- 3Maintain resuscitation and continuous monitoring in the scanner and stop or redirect if physiology deteriorates.
- 4Communicate critical images directly to the trauma leader and activate surgery or interventional radiology before the full report when necessary.
03ClosureTurn reports into treatmentPreliminary interpretation is available and care is moving to another area or team.+
- 1Reconcile examination, procedures and imaging, obtaining additional views or senior re-review when they disagree.
- 2Acknowledge the final report and every addendum, recording any change from the preliminary plan and informing the responsible specialty.
- 3Give each incidental finding a named owner, urgency category and communication plan rather than leaving it in a generic discharge summary.
- 4Re-image only for a defined new question such as physiological deterioration, evolving injury or inadequate original coverage.
08ComplicationsImportant consequences, why they occur and why they matter clinically.
Delay to source control
Unnecessary sequences, repeated transfers or imaging an unstable non-responder prolongs uncontrolled bleeding and substantially worsens survival.
Missed injury
Poor coverage, wrong contrast phase, motion, failure to image limb joints or failure to read scout and reformats can leave actionable pathology undetected.
Contrast-related harm
Hypersensitivity and extravasation occur acutely, while renal risk requires clinical context; emergency benefit usually outweighs theoretical delay for laboratory results.
Unowned result
Preliminary-final report discrepancy or incidental finding causes harm when no named clinician acknowledges it and arranges treatment or follow-up.
09Monitoring and follow-upTreatment response, safety checks and longer-term review.
- Continue ECG, oxygen saturation, pressure, temperature and waveform capnography for an intubated patient throughout scanner transfer and acquisition.
- Record physiology before leaving resus, during CT and immediately after, with a contingency destination for any deterioration.
- Inspect intravenous contrast sites for extravasation and monitor for acute hypersensitivity during and shortly after administration.
- Track preliminary, final and amended reports in the clinical record, naming who acknowledged each critical or incidental result.
- Repeat targeted examination after analgesia, waking or transfer because later clinical signs may expose an injury not apparent on the initial images.
10Special situationsVariants, exceptions and circumstances that change the usual approach.
CT is a destination decision
The key question is not whether CT is diagnostically useful, but whether the patient can reach and leave it safely.
FAST is not clearance
Focused ultrasound identifies some rapid targets but cannot reliably exclude retroperitoneal, bowel or early intraperitoneal injury.
Children need selective questions
Avoiding routine whole-body acquisition is compatible with decisive regional CT when a serious paediatric injury is suspected.
Contrast serves a hypothesis
Communicating the suspected vascular or organ injury allows radiology to choose phases that answer the clinical question.
A report requires an owner
Diagnostic quality is wasted when final changes and incidental findings do not reach someone responsible for action.
11Common pitfallsFrequent interpretation and management errors.
- 01
Taking a persistent non-responder to conventional CT because the mechanism was dramatic.
- 02
Using a negative eFAST examination to rule out all abdominal and retroperitoneal haemorrhage.
- 03
Applying an adult whole-body protocol routinely to a child without region-specific justification.
- 04
Withholding necessary maternal CT solely because pregnancy is possible or confirmed.
- 05
Failing to tell radiology about wounds, pulse deficits or the suspected bleeding source before acquisition.
- 06
Acting on a preliminary read but never checking the final report or addendum.