Shiu M. Ho

Abdominal injuries without hemoperitoneum: a potential limitation of focused abdominal sonography for trauma (FAST)

BACKGROUND Focused abdominal sonography for trauma (FAST) relies on hemoperitoneum to identify patients with injury. Blunt trauma victims (BTVs) with abdominal injury, but without hemoperitoneum, on admission are at risk for missed injury. METHODS Clinical, radiologic, and FAST data were collected prospectively on BTVs over a 12-month period. All patients with FAST-negative for hemoperitoneum were further analyzed. Examination findings and associated injuries were evaluated for association with abdominal lesions. RESULTS Of 772 BTVs undergoing FAST, 52 (7%) had abdominal injury. Fifteen of 52 (29%) had no hemoperitoneum by admission computed tomographic scan, and all had FAST interpreted as negative. Four patients with splenic injury underwent laparotomy. Six other patients with splenic injury and five patients with hepatic injury were managed nonoperatively. Clinical risk factors significantly associated with abdominal injury in BTVs without hemoperitoneum include: abrasion, contusion, pain, or tenderness in the lower chest or upper abdomen; pulmonary contusion; lower rib fractures; hemo- or pneumothorax; hematuria; pelvic fracture; and thoracolumbar spine fracture. CONCLUSIONS Up to 29% of abdominal injuries may be missed if BTVs are evaluated with admission FAST as the sole diagnostic tool. Consideration of examination findings and associated injuries should reduce the risk of missed abdominal injury in BTVs with negative FAST results.

The accuracy of the CAGE, the Brief Michigan Alcoholism Screening Test, and the Alcohol Use Disorders Identification Test in screening trauma center patients for alcoholism.

OBJECTIVE To evaluate the accuracy of questionnaire screening instruments to identify lifetime alcohol dependence among trauma center patients. METHODS The study was conducted at a Level I trauma center between September 1994 and November 1996. Patients meeting eligibility requirements (> or = 18 years old, admission from injury scene, > or = 2 days of hospitalization, intact cognition) were evaluated for alcohol abuse and dependence. Screening instruments consisted of the CAGE, the Brief Michigan Alcoholism Screening Test, and the Alcohol Use Disorders Identification Test. Screening results were compared with lifetime alcohol dependence diagnoses made using the in-depth Psychoactive Substance Use Disorders section of the Structured Clinical Interview. Accuracy was quantified as sensitivity, specificity, positive/negative predictive values, and receiver operating characteristic curves (used to calculate area under the curve). RESULTS Of the 1,118 patients studied, lifetime alcohol dependence was diagnosed by Structured Clinical Interview in 397 (35.5%), and abuse was diagnosed in 90 (8.1%) others. The CAGE was the best predictor of lifetime alcohol dependence, i.e., had the largest area under the curve (93%) and the highest sensitivity (84%), specificity (90%), positive predictive value (82%), and negative predictive value (91%). Among patients testing positive for alcohol, 63% had a lifetime alcohol dependence diagnosis. CONCLUSION The CAGE is an efficient screening test to detect alcohol dependence in trauma center populations. It should be used in combination with alcohol testing to identify patients at risk of alcohol use problems.

Life-altering outcomes after lower extremity injury sustained in motor vehicle crashes.

BACKGROUND Lower extremity injuries (LEIs) sustained in vehicular crashes result in physical problems and unexpected psychosocial consequences. Their significance is diminished by low Abbreviated Injury Scale scores. METHODS Drivers who sustained LEIs were identified as part of the Crash Injury Research and Engineering Network (CIREN) and interviewed during hospitalization, at 6 months, and at 1 year. All were occupants of newer vehicles with seatbelts and airbags. RESULTS Sixty-five patients were followed for 1 year. Injuries included mild brain injury (43%), ankle/foot fractures (55%), and bilateral injuries (37%). One year post-injury, 46% reported limitations in walking and 22% with ankle/foot fractures were unable to return to work. Depression (39%), cognitive problems (32%), and post-traumatic stress disorder (18%) were significant in the mild brain injury group. CONCLUSIONS Long-lasting physical and psychological burdens may impede recovery and alter the lifestyle of patients with LEI. These issues need to be addressed by trauma center personnel.

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.

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.

Occupant and Crash Characteristics for Case Occupants With Cervical Spine Injuries Sustained in Motor Vehicle Collisions

BACKGROUND Motor vehicle collisions (MVCs) are the leading cause of spine and spinal cord injuries in the United States. Traumatic cervical spine injuries (CSIs) result in significant morbidity and mortality. This study was designed to evaluate both the epidemiologic and biomechanical risk factors associated with CSI in MVCs by using a population-based database and to describe occupant and crashes characteristics for a subset of severe crashes in which a CSI was sustained as represented by the Crash Injury Research Engineering Network (CIREN) database. METHODS Prospectively collected CIREN data from the eight centers were used to identify all case occupants between 1996 and November 2009. Case occupants older than 14 years and case vehicles of the four most common vehicle types were included. The National Automotive Sampling Systems Crashworthiness Data System, a probability sample of all police-reported MVCs in the United States, was queried using the same inclusion criteria between 1997 and 2008. Cervical spinal cord and spinal column injuries were identified using Abbreviated Injury Scale (AIS) score codes. Data were abstracted on all case occupants, biomechanical crash characteristics, and injuries sustained. Univariate analysis was performed using a χ analysis. Logistic regression was used to identify significant risk factors in a multivariate analysis to control for confounding associations. RESULTS CSIs were identified in 11.5% of CIREN case occupants. Case occupants aged 65 years or older and those occupants involved in rollover crashes were more likely to sustain a CSI. In univariate analysis of the subset of severe crashes represented by CIREN, the use of airbag and seat belt together (reference) were more protective than seat belt alone (odds ratio [OR]=1.73, 95% confidence interval [CI]=1.32-2.27) or the use of neither restraint system (OR=1.45, 95% CI=1.02-2.07). The most frequent injury sources in CIREN crashes were roof and its components (24.8%) and noncontact sources (15.5%). In multivariate analysis, age, rollover impact, and airbag-only restraint systems were associated with an increased odds of CSI. Using the population-based National Automotive Sampling Systems Crashworthiness Data System data, 0.35% of occupants sustained a CSI. In univariate analysis, older age was noted to be a significant risk factor for CSI. Airbag-only restraint systems and both rollover and lateral crashes were also identified as risk factors for CSI. In addition, increasing delta v was highly associated with CSIs. In multivariate analysis, similar risk factors were noted. Of all the restraint systems, seat belt use without airbag deployment was found to be the most protective restraint system (OR=0.29, 95% CI=0.16-0.50), whereas airbag-only restraint was associated with the highest risk of CSI (OR=3.54, 95% CI=2.29-5.46). CONCLUSIONS Despite advances in automotive safety, CSIs sustained in MVC continue to occur too often. Older case occupants are at an increased risk of CSI. Rollover crashes and severe crashes led to a much higher risk of CSI than other types and severity of MVCs. Seat belt use is very effective in preventing CSI, whereas airbag deployment may increase the risk of occupants sustaining a CSI. More protection for older occupants is needed and protection in both rollover and lateral crashes should remain a focus of the automotive industry. The design of airbag restraint systems should be evaluated so that they are not causative of serious injury. In addition, engineers should continue to focus on improving automotive design to minimize the risk of spinal injury to occupants in high severity crashes.

Use of blood alcohol concentration and laboratory tests to detect current alcohol dependence in trauma center patients.

OBJECTIVE To assess the utility of laboratory markers of severe alcoholism in a cross-sectional population of male trauma center patients, who have a high rate of current alcohol dependence (CAD). METHODS A total of 684 men were assessed for CAD by using standard criteria, all of whom had complete laboratory data. The ability of tests to predict CAD was ascertained by using Students t test, sensitivity, specificity, and area under the curve (AUC) of receiver operating characteristic curves. RESULTS Mean values of five tests were individually associated with a CAD diagnosis. Gamma-glutamyltransferase, aspartate aminotransferase, and mean corpuscular volume had sensitivities less than or equal to 0.51 and AUC less than or equal to 0.67. Blood alcohol concentration (BAC) and serum osmolality had sensitivities of 0.64 and 0.74 and AUC of 0.74 and 0.76, respectively. Each marker, when combined with BAC, showed little improvement in AUC over BAC alone. CONCLUSIONS Laboratory tests are not highly predictive of CAD in male trauma patients. A combination of BAC tests and interview screens is suggested for use in this patient population.

LOWER EXTREMITY TRAUMA IN VEHICULAR FRONT-SEAT OCCUPANTS: PATIENTS ADMITTED TO A LEVEL 1 TRAUMA CENTER

This study involves development of a data collection instrument with which to capture detailed information on crash reconstruction, biomechanics, engineering, and orthopedic aspects of leg/foot fractures. Data are being collected on patients admitted to a Level 1 trauma center so that postulates can be developed regarding mechanisms of injury. To be included in this study, the patient must have been a front seat occupant (restrained or unrestrained) of a late-model passenger vehicle or light truck/van involved in a collision, must not have been the victim of a rollover or ejection type crash, and must have sustained a lower extremity fracture distal to the femur. To date, data have been obtained for 42 trauma patients (22 men and 20 women). The mean Injury Severity Score for this group was 16, with an average of 2.2 lower extremity fractures distal to the femur per patient. The mean change in velocity (delta V) was 28.4 mph (45.7 km/h) (n = 39). Preliminary findings, including postulated patterns for mechanism of injury, are described in this paper.

Sociodemographic Characteristics Associated with Substance Use Status in a Trauma Inpatient Population

Abstract Substance use is significantly associated with physical injury, yet relatively little is known about the prevalence of specific substance use disorders among trauma patients, or their associated sociodemographic characteristics. We evaluated these issues in an unselected sample of 1,118 adult inpatients at the University of Maryland Shock Trauma Center, Baltimore, MD, who were interviewed with the psychoactive substance use disorder section of the Structured Clinical Interview for DSM-III-R. Among trauma inpatients, lifetime alcohol users (71.8% of subjects) were more likely male; users of illegal drugs (45.3%) were also more likely to be younger, unmarried, and poor. Patients with current drug abuse/dependence (18.8%) were more likely to be non-white, less educated, and poor; those with current alcohol abuse/dependence (32.1%) were also more likely male, unmarried, and older. These findings highlight the need for screening for substance use disorders in trauma settings and referral of patients to substance abuse treatment programs.

Risk of Psychoactive Substance Dependence Among Substance Users in a Trauma Inpatient Population

Abstract One measure of a substances addictive risk is the proportion of users who become dependent. This study evaluates the lifetime and current risk of substance dependence among lifetime substance users among trauma inpatients and provides a relative ranking of addictive risk among the substances. Data on use of 8 substance groups (alcohol, opiates, cannabis, cocaines other stimulants, sedative-hypnotics, hallucinogens, other drugs) were obtained by interview (Structured Clinical Interview for the DSM-III-R) from 1,118 adult trauma inpatients. Prevalence of lifetime dependence among lifetime users ranged from 80.7% for opiates and 70.9% for cocaine to 33.3% for hallucinogens and 26.6% for sedative-hypnotics. The rank order of addictive risk was similar to that found in the general population. Trauma inpatients had a higher absolute addictive risk than the general population, comparable to the risk found in patients in treatment for substance use disorders, suggesting the importance of screening trauma inpatients for substance dependence.