Calc Function

    • Calcs that help predict probability of a diseaseDiagnosis
    • Subcategory of 'Diagnosis' designed to be very sensitiveRule Out
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    Chief Complaint


    Organ System


    Patent Pending

    CHIP (CT in Head Injury Patients) Prediction Rule

    Predicts intracranial traumatic CT findings in patients with minor head trauma.


    Use in patients at least 16 years old presenting within 24 hours of blunt head trauma and GCS 13–14 (or GCS 15 with at least one of the following: LOC, short-term memory deficit, amnesia, seizure, vomiting, severe headache, intoxication, anticoagulant use or history of coagulopathy, external evidence of injury above the clavicles, neurologic deficit). Note: We recommend using the Canadian CT Head Rule over other adult head trauma decision rules, as it is the most widely validated.

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    If ≥1 major criterion OR ≥2 minor criteria are present, CT head is required.

    Major criteria:

    • Pedestrian or cyclist versus vehicle.
    • Ejected from vehicle.
    • Vomiting.
    • Post-traumatic amnesia ≥4 hours.
    • Clinical signs of skull fracture*.
    • GCS <15.
    • GCS deterioration ≥2 points (1 hour after presentation).
    • Use of anticoagulant therapy.
    • Post-traumatic seizure.
    • Age ≥60 years.

    Minor criteria:

    • Fall from any elevation.
    • Persistent anterograde amnesia**.
    • Post-traumatic amnesia of 2 to <4 hours.
    • Contusion of the skull.
    • Neurologic deficit.
    • Loss of consciousness.
    • GCS deterioration of 1 point (1 hour after presentation)
    • Age 40–60 years.

    *Any injury that suggests a skull fracture, such as palpable discontinuity of the skull, leakage of cerebrospinal fluid, “raccoon eye” bruising, and bleeding from the ear.

    **Persistent anterograde amnesia is any deficit of short-term memory.

    Dr. Marion Smits

    About the Creator

    Marion Smits, MD, is an associate professor and neuroradiologist at Erasmus University Medical Center in Rotterdam, Netherlands. She is the principal investigator of applied physiological MR neuroimaging, focusing on the non-invasive, in vivo visualization of brain function. Dr. Smits is also an honorary consultant and reader at University College London Hospital NHS Foundation Trust in London.

    To view Dr. Marion Smits's publications, visit PubMed

    About the Creator
    Dr. Marion Smits