Alcohol use among injured sets of drivers and passengers.

Crash report and blood alcohol concentration (BAC) data were linked for 109 injured driver/passenger pairs admitted to a Level I trauma center. Among those occupants, 47 drivers (43%) (mean BAC, 147 mg/dl) and 45 passengers (41%) (mean BAC, 127 mg/dl) were BAC+. No occupant was BAC+ in 57 crashes (52%); both were BAC+ in 40 (37%); and only one was BAC+ in 12 (11%). When both occupants were BAC+, the driver had the higher BAC in 68% of cases, and when one was BAC+, it was the driver 58% of the time. In 6 additional alcohol-related crashes with one driver and two passengers, the "wrong" occupant was driving on 5 occasions. Hence, in the 58 crashes involving BAC+ occupants, the least appropriate occupant was driving 67% of the time.

Lower extremity fractures in motor vehicle collisions: the role of driver gender and height.

In a previous study it was noted that there was a higher incidence of lower-extremity fractures among women drivers. Analyses were based on a linkage between trauma registry and police crash report data. The present study addresses the issue of whether the differences noted are attributed to driver gender or are merely a reflection of differences in driver height. An inverse association was noted between driver height and the incidence of lower-extremity fractures. Those shorter than average (5'7") for this population had a 64% increase in lower-extremity fracture, which can be mainly attributed to ankle/tarsal injuries. Thus, the incidence of these injuries appears to be a function of driver height, with an increase among shorter drivers, most of whom are women.

Effect of change in velocity on the development of medical complications in patients with multisystem trauma sustained in vehicular crashes.

Medical complications such as sepsis or multiple organ system failure increase the morbidity and mortality associated with injuries sustained in car crashes. This study addresses the question of the association, if any, between one crash characteristic, i.e. change in velocity (delta v), and subsequent medical complications. Data on seventy-six severely injured patients were obtained as part of an in-depth, trauma-center-based study of the biomechanics of vehicular trauma. Factors found to be predictive of the development of complications included patient age > or = 36 years, delta v > or = 30 mph, and injury severity score > or = 25. Vehicle occupants involved in crashes with a delta v > or = 30 mph had a risk of complications more than five times greater than for those in the lower delta v group. Better knowledge of the dynamics and severity of the crash could help clinical staff anticipate the development of complications and initiate timely prevention strategies.

Helmet use, patterns of injury, medical outcome, and costs among motorcycle drivers in Maryland.

A comprehensive study was conducted of all motorcycle traffic crashes occurring in Maryland during a one-year period. All available medical and cost data were linked with police crash reports. During the study period, 1,900 motorcycle drivers were involved in crashes. The data indicated that (i) helmet usage was 35% overall, 30% among fatally injured drivers, and only 16% among drivers with a history of drug/alcohol conviction, (ii) unhelmeted drivers seen at an emergency department were almost twice as likely to have sustained head injury (40%) as were helmeted drivers (21%) (the corresponding percentages for hospitalized drivers were 55% and 38%), and (iii) acute care cost for unhelmeted drivers was three times ($30,365) that of helmeted drivers.

Marijuana and other drug use among automobile and motorcycle drivers treated at a trauma center.

Serum from injured automobile and motorcycle drivers treated at a trauma center was tested for delta-9-tetrahydrocannabinol activity to determine precrash marijuana use. From June 1990 to March 1991, samples from approximately 20 automobile drivers per month and all motorcycle drivers were available for testing. Also, toxicology screens were performed for ethyl alcohol, cocaine, and phencyclidine (PCP) among the driver groups. Six (2.7%) of the 225 automobile (AUT) drivers and 34 (32.0%) of the 106 motorcycle (MTC) drivers were THC+ (p < .001). Compared with a prior study, the THC+ rate decreased significantly from 31.8% among AUT drivers (p < .001) but had not changed significantly from the 38.6% rate among MTC drivers. Positive toxicology rates were higher among the 261 MTC drivers compared to the 1,077 AUT drivers tested for ETOH, CO, and PCP, being 47.1% vs 35.2% (p < .001), 5.0% vs 8.0% (p < .08), and 1.5% vs 3.1% (NS), respectively.

Alcohol use, driving records, and crash culpability among injured motorcycle drivers.

Alcohol use, driving records, crash culpability, and crash conviction rates for 165 injured motorcycle drivers (MTCDs) were studied. Of the 165 MTCDs, 53.3% tested positive for alcohol (BAC+). Culpability determinations (n = 150) revealed that 83% of BAC+ and 46% of BAC-MTCDs caused their crashes (p < 0.001). Driving records (n = 145) revealed the following prevalence of one or more convictions for BAC+ and BAC-MTCDs: impaired driving (29% vs. 7%, p < 0.001); speeding (74% vs. 58%, p < 0.05); and reckless driving (68% vs. 44%, p < 0.002). Of the surviving culpable impaired MCTDs (n = 48), 16.7% received crash-related convictions, 12.5% received alcohol-related convictions. The reasons for the low conviction rates are probably multifactorial.

Alcohol/drug abuse, driving convictions, and risk-taking dispositions among trauma center patients.

The objective of this study was to evaluate the relationship between alcohol/drug abuse diagnoses, driving convictions (speeding, reckless driving, impaired driving, license violations), and risk-taking dispositions among a series of injured drivers admitted to a trauma center. The driving records of 778 patients were linked to diagnoses of psychoactive substance use disorders (PSUDs), admission blood alcohol concentration (BAC), mode of injury, and results of a risk-taking disposition survey. Twenty-nine percent of patients had one or more convictions in the 3 years before injury. Types of violation were not related to mode of injury. Although there was a positive association between prior impaired-driving convictions, current alcohol dependence, and a BAC + status, a consistent pattern relative to other violations, PSUDs, and BAC status was not apparent. Risk-taking disposition scale scores indicated that patients without PSUDs and without convictions tended toward less risk-taking behavior than patients with PSUDs and with convictions. The complex inter-relationships between PSUDs, risk-taking dispositions, and being convicted of driving dangerously require additional study so that intervention programs and injury prevention initiatives can be targeted effectively.

Lower limb response and injury in frontal crashes.

This article examines two observational and two experimental data sets that emphasize lower limb injuries in passenger car crashes. Statistics show that 60% of moderate-to-severe below-knee injuries sustained by front seat occupants in head-on crashes occur with > 3 cm of footwell intrusion. Moreover, crash tests and computer simulations of car-to-car frontal offset collisions show no causal relationship between the magnitude of footwell intrusion and the axial load measured in the dummy leg. This article correlates below-knee injuries with several factors that influence their frequency and severity, such as the vehicle change in velocity, the magnitude of footwell intrusion, the rate and timing of the intrusion and the size of the vehicle. The vehicle change in velocity and the intrusion rate and timing had the greatest influence on the risk of lower limb injury, while the other factors had much less of an effect.

Alcoholism at the time of injury among trauma center patients: vehicular crash victims compared with other patients.

A structured in-depth interview employing standardized criteria was used to determine the prevalence of lifetime and current alcohol dependence (alcoholism) in unselected consecutive patients admitted to a regional Level I trauma center. Of 629 patients, 157 (25.0%) were current alcoholics at the time of injury. An additional 87 (13.8%) were diagnosed as lifetime non-current alcoholics. There was no significant difference in the rates of current alcohol dependence among patients injured in vehicular crashes (23.5%), other unintentional trauma victims (29.3%), and those injured as a result of violence (24.6%). Of BAC+ (blood alcohol concentration positive) patients, 54.5% were current alcoholics. However, 14.4% of alcohol-negative patients were also diagnosed as alcohol dependent.

Police perception of intoxication among injured pedestrians.

To assess police officers' accuracy in perceiving alcohol or drug intoxication of injured pedestrians, blood test results from pedestrians struck by vehicles and admitted to a Level I trauma center for a 3-year period were linked to police reports of the crashes. Police officers were 64.5% sensitive and 99.3% specific in identifying alcohol use in injured pedestrians when blood tests were positive for alcohol, and 2.2% sensitive and 100% specific in identifying other drug use when blood tests were positive for drugs other than alcohol. Those with higher blood ethanol levels were more often correctly assessed to be under the influence. Injury Severity Score and the presence of head injuries had no apparent effect on police assessments. In conclusion, police assessment of substance abuse is extremely specific, but not particularly sensitive. Efforts are needed to improve police evaluations. The effect of increased legal actions on recurrent alcohol and drug-related injuries remains to be seen.

Characteristics of traffic crashes in Maryland (1996-98): differences among the youngest drivers.

Motor vehicle crashes (MVCs) are the leading cause of death among teenagers in the US. The present study examines how crash rates and crash characteristics differed among drivers aged 16, 17, 18, 19, 20, and 21 in the state of Maryland from 1996 through 1998. The results show that, based on police reports, the youngest drivers have the highest rate of MVC per licensed driver and per annual miles driven. Furthermore, crash characteristics suggest that inexperience rather than risky driving may account for the differing rates. Younger drivers had their crashes during the day in clear weather while drinking less.

Medical conditions and car crashes.

Most previous studies of medical conditions associated with driver safety have focused on specific diseases. This analysis is based on a linkage of police report and hospital discharge data, and correlates various medical diagnostic categories and specific conditions with police determinations of driver culpability for all drivers admitted to Maryland hospitals during a 3-year period. Using odds ratios, various conditions have been identified which are associated with an increased risk of crash culpability. Further research is needed to confirm these findings, and to determine the role of the conditions vs. the possible influence of medications prescribed to treat these conditions.

Causes and outcomes of mild traumatic brain injury: an analysis of CIREN data.

Approximately one-half of vehicle occupants with traumatic brain injury (TBI) have a mild TBI (admission Glasgow Coma Scale (GCS) score of 13-15 with transient loss of consciousness). However, despite the label of "mild", many of these injuries result in long-term consequences; frequently these sequelae go unrecognized, as the patients are lost to medical follow-up. The Crash Injury Research Engineering Network (CIREN) project affords us the opportunity to examine the crash circumstances, injury sources and outcomes of mild TBI cases in greater detail.

Consequences and costs of lower extremity injuries.

Lower extremity injuries resulting from motor vehicle crashes are common and have become relatively more important as more drivers with newer occupant restraints survive high-energy crashes. CIREN data provide a greater level of clinical detail based on coding guidelines from the Orthopedic Trauma Association. These detailed data, in conjunction with long-term follow-up data obtained from patient interviews, reveal that the most costly and disabling injuries are those involving articular (joint) surfaces, especially those of the ankle/foot. Patients with such injuries exhibit residual physical and psychosocial problems, even at one year post-trauma.

Quality control aspects of blood pressure measurements in the Multiple Risk Factor Intervention Trial.

Quality control of an ongoing study of blood pressure must be an active, dynamic process in which attempts are continually made to reduce error and bias and maintain comparability among clinics. Training is an important means of initiating and maintaining proper procedures. In addition, changes in procedures during the trial must be properly evaluated so that their impact upon the conduct of the trial is known and, if necessary, quantifiable. The monitoring of quality measurement of blood pressure in a large clinical trial such as MRFIT must be a two-pronged effort that considers observation and evaluation of methods of measuring blood pressure in actual clinical practice and evaluation of data resulting from these procedures.

Injured drivers and alcohol use: culpability, convictions, and pre- and post-crash driving history.

The culpability, crash-related traffic convictions, and pre- and post-crash driving records of a group of injured impaired (blood alcohol level greater than 80 mg/dl) drivers (N = 58) who were admitted to a Level I trauma center were compared with a group of admitted unimpaired drivers (N = 92). Both groups of drivers were 21 years of age or older, sustained moderate injuries (defined as having no injury of the brain, spinal column or cord, extremity, or pelvis with an Abbreviated Injury Score of greater than 2), and were discharged home. In the 140 crashes in which culpability was clearly defined, the impaired drivers caused a significantly greater percentage of their crashes (92.7%) compared to unimpaired (64.7%) drivers (p less than 0.001). Of the 55 unimpaired drivers who were considered culpable of causing their crashes, 12.7% received a traffic conviction compared with 39.2% of the 51 culpable impaired drivers. The mean number of total pre-crash traffic violations was higher for impaired drivers than for unimpaired drivers (p less than 0.01). While the mean number of total post-crash convictions for unimpaired and impaired was not significantly different, the mean number of pre- and post-crash alcohol convictions was significantly higher for impaired drivers compared to unimpaired drivers (p less than 0.02). The data suggest that injury protects from legal prosecution and does not alter impaired driving practices.

Injury patterns associated with direction of impact: drivers admitted to trauma centers.

Clinical data on the nature and severity of injuries was linked with data from police crash reports for 3675 car or truck drivers admitted to trauma centers. Different patterns of injuries were noted for drivers in frontal compared with left lateral collisions. Injuries to the face and lower extremities were significantly greater in frontal collisions; thorax, abdominal, and pelvic injuries were significantly greater in lateral collisions. In addition, drivers in lateral collisions were found to have significantly more multiple injuries to the abdomen and thorax. Despite no difference in mean injury Severity Score, drivers in left lateral collisions had a significantly higher mortality rate; moreover, this increased mortality was not merely a reflection of the increased incidence of lateral collisions among older drivers. In conclusion, information on direction of impact has potential use for clinical decision making, since drivers in lateral collisions have a higher incidence of occult abdominal and thoracic injuries.

Twenty-four-hour ambulatory blood pressure in normotensive adolescent children of hypertensive and normotensive parents.

Twenty-four-hour ambulatory blood pressure measurements were obtained during usual daily activities from two groups of normotensive adolescents: Cases had at least one hypertensive parent, and controls had both parents normotensive. Automatic measurements were programmed at 7.5-minute intervals. For each subject, within each of three time periods, the data were summarized by descriptors of the frequency distribution and the frequency spectrum. The time periods were sleep, school hours, and other waking hours. Regression analyses examined the relation between the blood pressure monitoring descriptors and case-control status adjusted for non-blood-pressure variables found to relate to case-control status. In stepwise logistic regression analysis with case-control status as the dependent variable, it was found that the mean level of diastolic pressure during school hours was significant, whereas the standard resting measurement was not. In linear regression analyses with blood pressure monitoring descriptors and standard resting measurements as dependent variables, several monitoring descriptors were found to be significantly related to the interaction between case-control status and certain variables that can affect blood pressure, such as weight and the presumed stress of school; no such relations were found for the standard resting measurements. These findings demonstrate the superiority of the ambulatory monitoring variables over the standard resting measurements in studying case-control differences.

Occupational exposure to electromagnetic fields and the occurrence of brain tumors. An analysis of possible associations.

To explore the association between occupation and the occurrence of brain tumor, an epidemiologic study was conducted using data from the death certificates of 951 adult white male Maryland residents who died of brain tumor during the period 1969 through 1982. Compared with the controls, men employed in electricity-related occupations, such as electrician, electric or electronic engineer, and utility company serviceman, were found to experience a significantly higher proportion of primary brain tumors. An increase in the odds ratio for brain tumor was found to be positively related to electromagnetic (EM) field exposure levels. Furthermore, the mean age at death was found to be significantly younger among cases in the presumed high EM-exposure group. These findings suggest that EM exposure may be associated with the pathogenesis of brain tumors, particularly in the promoting stage.

A quantitative method for cost reimbursement and length of stay quality assurance in multiple trauma patients.

OBJECTIVE: To develop a statistically valid method for trauma reimbursement and quality assurance (QA) length-of-stay filters. This is needed because diagnosis related group (DRG)-based trauma payment systems assume a random sampling of injury severities from a normally distributed population and thus result in economic disincentives to level I trauma centers. METHODS: 142 trauma patients with MVC blunt multisystem injuries (MSI) (ISS > or = 16) were studied concurrently during their hospital course. SETTING: Level I regional trauma center. OUTCOME MEASURES: Outcome measures were (dependent variables) length of stay (LOS) and state-approved hospital charges (COST). RESULTS: Mean acute care COST was $74,310, but the distribution of COST was log normal, rather than Gaussian normal as assumed by DRGs. The LOS for MSI was more than twice the average for all trauma (22 vs. 9 days), reflecting skewed severities of level I patients and was related to COST (r2 = 0.802; p < 0.0001). The ISS alone was a weak determinant of COST or LOS (r2 = 0.05; p < 0.0001). The best single determinant of COST and LOS was survival (r2 = 0.15; p < 0.0001): as it increased, it increased LOS. The most costly injuries (all p < 0.0001) involved the lower extremity (LE) or hip joint (HIP), whereas sepsis and pulmonary and surgical complications constituted the most costly complications (all p < 0.0001). Regression models that accounted for the log-normal distribution of the dependent variable and based on binary variables for survival, LE and HIP injuries, and the complications of sepsis, ARDS, pulmonary failure, MOFS, plus ISS, explained nearly two thirds of the variability in COST (r2 = 0.621; p < 0.0001) or LOS (r2 = 0.687; p < 0.0001) and the residuals were normally distributed. CONCLUSIONS: These models provide a valid method of reimbursement for MSI trauma for level I trauma centers, since the data imply that good care associated with survival from specific complications of MSI are the major determinants of COST, rather than the specific type of injury or the resultant ISS. Moreover, using survival and ISS plus the disease-related complications as determinants of LOS, this method can be applied to any U.S. region since local factors can be used to adjust hospital COST as a highly correlated function of LOS. This method also permits identification of LOS outliers for QA, taking into account the influence of injury complications.