Whole-Body Trauma CT
Whole body trauma CT is a single rapid examination of a severely injured patient, covering the head to the pelvis (and often the proximal thighs), usually with an additional cervical spine reformat. It is performed in the resuscitation room or in an adjacent scanner after initial stabilisation.
A non-contrast CT head and cervical spine is followed by a contrast enhanced scan of the neck, chest, abdomen and pelvis.
In a single pass technique, one contrast bolus (100 to 150 mL of high concentration non-ionic medium at 3 to 5 mL each second, sometimes split in two portions) is injected. Arterial phase scanning of the chest and portal venous phase of the abdomen and pelvis are done in a single acquisition.
Delayed images (3 to 5 minutes) are added for suspected urinary tract injury, bowel injury, or vascular lesions with slow flow. The entire examination takes 10 to 15 minutes, and scanning itself under 2 minutes with a modern scanner. Effective dose is about 15 to 25 mSv for the whole body.
Trauma is a leading cause of death under 45 years, causing about 4.4 million deaths each year.
Whole body CT has a sensitivity of over 95% for major thoracic, abdominal and pelvic injury and over 98% for intracranial haemorrhage and unstable spine fractures. In randomised and observational studies it shortens time to diagnosis and may reduce mortality in severely injured patients, though the evidence for survival benefit across all trauma patients is mixed.
It replaces sequential radiographs, ultrasound and selective CT in many trauma centres.
Indications. Severe blunt trauma with high energy mechanism (high speed collision, ejection, fall from height, pedestrian or cyclist struck), physiological instability that has responded to resuscitation, altered consciousness, multiple injuries, or inability to assess clinically. Suspected life threatening haemorrhage that is not obvious from bedside tests. Penetrating trauma in a stable patient.
Polytrauma in children (selective use) and in older adults (lower threshold). Not for haemodynamically unstable patients who need immediate surgery or interventional radiology (bedside ultrasound, chest and pelvic radiographs are used), minor trauma with low risk features, or isolated limb injury.
Contraindications and precautions. Haemodynamic instability not responding to resuscitation: the patient goes to theatre or to angioembolisation. Pregnancy: a clinical decision with a low threshold in major trauma, as maternal survival comes first; the foetal dose from the abdominal scan is within 10 to 50 mGy. Children: use selective, size adjusted low dose techniques, and avoid routine whole body scanning.
Previous contrast reaction does not delay the scan in life threatening injury. Continuous monitoring of airway, breathing and circulation, and the trauma team stays with the patient. Cervical spine precautions are maintained. Metal objects and lines are positioned to avoid artefact.
Preparation and technique. The patient arrives intubated, immobilised on a spinal board or scoop, with cannulas in both antecubital veins (18 G or larger) and monitoring. Arms are raised over the head if possible. A topogram sets the range.
A non-contrast head and neck scan (4 to 5 mm, with thin cervical spine reconstructions) is followed by the contrast phase scan from the head or neck to the symphysis (or to mid-thigh if pelvic or femoral injury).
Arterial phase (bolus tracking in the descending aorta) covers the chest, with portal venous phase for the abdomen and pelvis, and a delayed phase (at 3 to 5 minutes) is added when kidneys, ureters, bladder or bowel injury, or slow bleeding are suspected.
Reformats of the spine are produced from chest and abdominal data in sagittal and coronal planes. Limb scans are added for suspected arterial injury. Initial reporting is done at the scanner by the trauma radiologist (the "hot" read, critical findings called immediately), followed by a full report.
