Canadian CT Head Injury / Trauma Rule

Intended for alert patients with blunt head trauma (commonly taught with GCS 15 for the medium-risk limb). Check any features that apply.

High risk (neurosurgical intervention risk on teaching rule)

GCS score <15 at 2 hours after injury Suspected open or depressed skull fracture Any clinical sign of basilar skull fracture Two or more episodes of vomiting Age 65 years or older

Medium risk (brain injury on CT risk — still warrants CT in teaching rule)

Retrograde amnesia ≥30 minutes before the event Dangerous mechanism (pedestrian struck, thrown from vehicle, fall >1 m / 5 stairs, rollover, high-speed crash, bicycle vs vehicle)

Educational tool only—not for diagnosis or treatment decisions.

Canadian CT Head Injury / Trauma Rule

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