Blood alcohol concentrations in seriously injured drivers of motor vehicle crashes and their comparison with forensic driving under the influence investigations.

INTRODUCTION

This study evaluated the prevalence of alcohol and the blood alcohol concentrations (BAC) among injured motor vehicle crash (MVC) patients admitted to a trauma center in Miami-Dade County, Florida. Results were compared with the BACs of driving under the influence (DUI) investigations in Miami-Dade County to determine whether there were significant differences in BAC among injured drivers and DUI investigations.

METHOD: Patients included in the 7-month study had a blood sample provided for testing. Forensic blood specimens from DUI investigations in Miami-Dade County with incident dates in the patient specimen collection period were reviewed. Trauma specimens were analyzed for ethanol utilizing a gas chromatograph-flame ionization detector. DUI blood specimens were analyzed for ethanol using the same or comparable methods.

RESULTS

Ethanol was detected in 23.8% of trauma patient drivers, with 19.6% having a BAC > 0.08 g/dL. Trauma patient BACs ranged from 0.023-0.388 g/dL (mean: 0.165 ± 0.073 g/dL). Among DUI investigations, 77.5% of subjects had ethanol detected, all with BAC > 0.08 g/dL, ranging from 0.125-0.358 g/dL (mean: 0.206 ± 0.062 g/dL). A significant main effect of driver type (p < 0.05) and significant interactions between type and sex and between type and age were observed.

CONCLUSION

Alcohol was frequently detected among seriously injured drivers of an MVC, with most exceeding the legal limit. Although DUI investigation subjects exhibited significantly higher mean BACs, trauma patients also demonstrated concentrations consistent with impairment. Differences between groups may reflect enforcement practices rather than a reduced prevalence of alcohol-impaired driving.