In spite of all the education, public awareness campaigns, and outreach programs, drinking and driving continues to be a problem that our society faces each day. According to the U.S. Department of Transportation National Highway Traffic and Safety Administration’s Traffic Safety Facts, an alcohol-impaired driving fatality occurred every 48 minutes in 2009. That same year, 10,839 people were killed in alcohol-impaired driving crashes, with the 21- to 24-year-old age group comprising more than one-third of all fatalities. Alcohol-related fatalities accounted for 32 percent of the total of all motor vehicle traffic fatalities that year.*
Alcohol-impaired drivers are defined as those drivers who have blood alcohol concentrations (BAC) of .08 grams per deciliter (g/dl) or greater and are the operators of any motor vehicle, including a motorcycle. In 2010, according to a Centers for Disease Control and Prevention press briefing, alcohol-impaired adults in the U.S. got behind the wheel 112 million times, which averages out to about 300,000 episodes of drinking and driving per day.† Whereas all of the above statistics are lower than those for previous years, alcohol-impaired driving remains a significant public health concern.
“Drinking alcohol”—also called ethanol, ethyl alcohol, pure alcohol, or grain alcohol—is a flammable, volatile drug with intoxicant properties. The alcohol in beverages is created through the process of fermentation, in which yeast fungus feeds on a substrate (sugar/starch) found in select plants, such as grapes or barley. During this process, ethyl alcohol is excreted along with carbon dioxide. The different tastes, colors, flavors, and strengths come from the use of various vegetables or fruits, as well as other additives, the diluting substances, and the by-products used. This fermentation process is one of the earliest biotechnologies undertaken by humanity that spans across time from the ancients through the moonshine stills, prohibition, and up to the sophisticated microbreweries of today. The standard measure for an alcoholic beverage in the U.S. is any drink that contains six-tenths of an ounce (14.0 grams or 1.2 tablespoons) of pure alcohol. This amount is found in 12 ounces of a regular beer or wine cooler, 8 ounces of malt liquor, 5 ounces of wine, or 1.5 ounces of 80 proof distilled spirits or liquor (such as rum, gin, vodka, or whiskey).‡
To examine the occurrence of alcohol-related injured drivers of motor vehicles in the National Trauma Data Bank® (NTDB) research dataset for 2010, admissions medical records were searched using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM). Specifically searched were external cause of injury E codes 810 (motor vehicle crash with train); 811 (motor vehicle crash with re-entrant motor vehicle); 812 (motor vehicle crash with another motor vehicle); 813 (motor vehicle crash with other vehicle); 814 (motor vehicle crash with pedestrian); 815 (motor vehicle crash with collision on highway); 816 (motor vehicle crash due to loss of control); and 819 (motor vehicle crash, unspecified nature). These records were searched by the E code post decimal value of .0 for driver of a car or .2 for driver of a motorcycle (motorcyclist).
A total of 128,047 records for drivers/motorcyclists were uncovered. In all, 103,816 records contained a hospital discharge status, including 79,598 patients discharged to home, 12,153 to acute care/rehab, and 8,687 sent to skilled nursing facilities; 3,378 died. These patients were 67.5 percent male, on average 41.5 years of age, had an average hospital length of stay of 6.0 days, an intensive care unit length of stay of 6.3 days, an average injury severity score of 12.2, and were on the ventilator for an average of 7.4 days.
A total of 73,942 drivers/motorcyclists were tested for alcohol, with 35 percent testing positive. Of the drivers/motorcyclists who died and were tested, 26 percent were legally impaired based upon their BAC (see Figures 1 and 2).
Web pages that boast BAC calculators are available and can help people determine whether it is safe to drive after drinking by analyzing weight, gender, number of drinks containing alcohol consumed, and the time over which they were consumed. However, many factors go into determining an individual’s specific blood alcohol level, including what and when the person may have eaten or if the individual is taking any medications. There are smartphone applications (apps) that have BAC calculators; one even uses the phone’s camera to assess eye movements for horizontal gaze nystagmus to determine BAC.
The best strategy is to be responsible and to know one’s personal limitations. When those limits have been exceeded, people should consider alternate modes of transportation or travel with designated drivers. In fact, instead of using that smartphone to calculate BAC, it’s probably best to use it to call a cab.
Throughout the year, we will be highlighting data through brief reports in the Bulletin. The NTDB Annual Report 2011 is available on the ACS website as a PDF file and as a PowerPoint presentation at www.ntdb.org. In addition, information regarding how to obtain NTDB data for more detailed study is available on the website. If you are interested in submitting your trauma center’s data, contact Melanie L. Neal, Manager, NTDB, at email@example.com.
Statistical support for this article has been provided by Chrystal Price, data analyst, NTDB.
*Department of Transportation (U.S.), National Highway Traffic Safety Administration (NHTSA). Traffic Safety Facts 2009: Alcohol-Impaired Driving. Washington (DC): NHTSA; 2010.
†Centers for Disease Control and Prevention. Vital signs: Alcohol-impaired driving among adults—United States, 2010. Available at: http://www.cdc.gov/media/releases/2011/t1004_alcohol_impaired.html. Accessed March 13, 2012.