Diffuse axonal injury in patients with head injuries: an epidemiologic and prognosis study of 124 cases.

BACKGROUND: Diffuse axonal injury (DAI) is usually associated to severe trauma. Recent imaging advances made its diagnosis easier. Its prognosis impact is not yet well established. The aim of this article is to describe the epidemiologic, clinical, and radiologic features of posttraumatic DAI and to study its prognosis impact on mortality and outcome according to Glasgow Outcome Scale.

METHODS: This is a retrospective study over a 4-year period (2004-2007) of 124 patients admitted for head trauma. Demographic, clinical, biological, and radiologic findings were recorded at admission and during intensive care unit stay.

RESULTS: Mean age (±standard deviation) was 28 years±15.8 years. Cranial computed tomography scan was sufficient enough to diagnose DAI in 31 patients. Magnetic resonance imaging was performed in 105 patients with a delay of 7.7 days±8.6 days. Most patients were classified as stage II (49.5%) or stage III (44.8%) according to Gentry's classification. In a multivariate analysis, factors associated with higher mortality were dysautonomia (p=0.018; odds ratio [OR]=4.17), hyperglycemia≥8 mmol/L (p=0.001; OR=3.84) on intensive care unit admission, and subdural hematoma (p=0.031; OR=3.99), whereas factors associated to poor outcome according to Glasgow Outcome Scale score were Glasgow Coma Scale score<8 (p=0.032, OR=3.55), secondary systemic injuries score≥3 (p=0.034, OR=2.83), hyperglycemia≥8 mmol/L (p=0.002, OR=5.55), and DAI count≥6 (p=0.035, OR=3.33). In patients with pure DAI, the absence of consciousness recovery was the unique independent factor of mortality (p<0.001, OR=116.4), whereas only transfusion need was an independent factor of poor outcome (p=0.017, OR=4.44).

CONCLUSION: Dysautonomia, hyperglycemia, and subdural hematoma are the main factors associated to higher mortality when DAIs are diagnosed, whereas a DAI count≥6 is associated to poor outcome. Magnetic resonance imaging classification did not have a prognosis value even in patients with pure DAI.