Core IMPACT Model — Validated for 6-month GOS prediction.
TBI Outcome Probe
Calculate the 6-month probability of favorable outcome by integrating core demographic and physiologic data points.
Guidelines & Evidence
Clinical Details
Section 1
When to Use
When to Use
Prognostic assessment of moderate to severe Traumatic Brain Injury (TBI).
Use in adult patients (Age > 14).
Calculating probabilities of 6-month mortality and unfavorable outcome (GOS 1–3).
Standardizing multidisciplinary discussion regarding Goals of Care.
Section 2
Formula & Logic
Core Prognostic Variables
Age: The strongest independent predictor of outcome.
GCS Motor Response: Determines the depth of traumatic coma.
Pupil Reactivity: Reflects brainstem integrity.
Secondary Insults: Hypoxia and hypotension significantly worsen the primary injury profile.
Section 3
Pearls/Pitfalls
The "Resuscitation" Rule
The IMPACT model relies on the POST-RESUSCITATION GCS. If the initial GCS was low due to shock or hypoxia that has since been corrected, use the improved GCS value for the model. Scoring a patient while they are hypoxic or hypotensive will produce an erroneously pessimistic prognosis.
Section 4
Evidence Appraisal
Primary Reference
Predicting outcome after traumatic brain injury: development and international validation of prognostic scores based on admission characteristics
