Pedestrian Versus Motor Vehicle Accidents: An Analysis of 5,000 Patients
RESULTS
There were a total of 37,110 patients in the trauma database between January 1, 1994, and December 31, 1996. Pedestrian cases represented 5,476 (15%). We excluded 476 patients either because the injury did not satisfy our search criteria (pedestrian injuries not due to motor vehicles were excluded) or because patient data were incomplete. The data on 5,000 hospitalized patients were available for review and constitute the study population of this report. The average age was 27.6±0.3 years. The majority were male (66%). There were 1,904 pediatric patients (38%), 2,696 adults (54%), and 400 elderly (8%). Hispanics were the major ethnic group (54%) (Table 1).
Table 1. Demographics
| Characteristic | n | % |
| Average age (±SEM) (y) | 27.6 ± 0.3 | -- |
| Gender | ||
| Male | 3,321 | 66.4 |
| Female | 1,679 | 33.6 |
| Age group | ||
| Pediatric | 1,904 | 38.1 |
| Adult | 2,696 | 53.9 |
| Elderly | 400 | 8.0 |
| Ethnicity | ||
| Hispanic | 2,699 | 54.0 |
| African American | 931 | 18.5 |
| White | 818 | 16.4 |
| Asian | 229 | 4.6 |
| Other | 323 | 6.5 |
Injury severity and hospital stay for the three age groups are detailed in Table 2. Overall, children had a significantly lower ISS and higher RTS among the three groups. Hospital and ICU stays were also shortest among these patients. The anatomic distribution of injuries is detailed in Table 3. Head and neck injuries constituted 30% of total injuries, 89% of which involved the cranium or the brain. Among musculoskeletal injuries, those involving the lower extremity were most common (58.9%), followed by the upper extremity (19.0%) and the pelvis (11.4%). Among abdominal injuries, the majority involved the solid organs (57.1%). Injuries of the gastrointestinal tract, abdominal blood vessels, and the genitourinary tract constituted 12.7% of abdominal injuries.
Table 2. Injury Severity
| Measure | Pediatric | Adult | Elderly | Total |
| ISS* | 6.8 ± 0.2 | 8.9 ± 0.2 | 12.3 ± 0.7 | 8.4 ± 0.1 |
| RTS † | 7.5 ± 0.9 | 7.3 ± 0.03 | 7.2 ± 0.1 | 7.4 ± 0.02 |
| GCS * | 13.9 ± 0.1 | 13.2 ± 0.1 | 12.5 ± 0.2 | 13.4 ± 0.1 |
| ICU (d) † | 4.6 ± 0.3 | 7.8 ± 0.5 | 6.8 ± 0.8 | 6.5 ± 0.3 |
| Hospital (d) † | 4.9 ± 0.2 | 8.8 ± 0.2 | 9.6 ± 0.6 | 7.4 ± 0.2 |
Data are presented as mean ± SEM.
* Significant difference observed between each and every age group; p<0.001.
† Values for the pediatric age group differ from either adults or elderly; p<0.001. No difference was observed between adults and the elderly.
GCS, Glasgow Coma Scale; ISS, Injury Severity Score; RTS, Revised Trauma Score.
Table 3. Injury Distribution
| Pediatric | Adult | Elderly | Total† | |||||
| Location | n | % | n | % | n | % | n | % |
| Head and neck | 1,592 | 34.6 | 1,810 | 26.7 | 361 | 31.0 | 3,763 | 30.0 |
| Intracranial | 1,433 | 31.1 | 1,605 | 23.7 | 327 | 28.1 | 3,365 | 26.8 |
| Face | 78 | 1.7 | 161 | 2.4 | 28 | 2.4 | 267 | 2.1 |
| Neck | 81 | 1.8 | 44 | 0.6 | 6 | 0.5 | 131 | 1.1 |
| Spine | 18 | 0.4 | 177 | 2.6 | 35 | 3.0 | 230 | 1.8 |
| Chest | 44 | 1.0 | 194 | 2.9 | 63 | 5.4 | 301 | 2.4 |
| Abdomen or pelvis | 145 | 3.0 | 306 | 4.5 | 39 | 3.4 | 490 | 3.9 |
| Musculoskeletal | 1,023 | 22.2 | 2,817 | 41.6 | 465 | 40.0 | 4,305 | 34.3 |
| Upper extremity | 166 | 3.6 | 537 | 7.9 | 117 | 10.1 | 820 | 6.5 |
| Lower extremity | 662 | 14.4 | 1,634 | 24.1 | 242 | 20.8 | 2,538 | 20.2 |
| Pelvis | 75 | 1.6 | 357 | 5.3 | 63 | 5.4 | 495 | 3.9 |
| Other | 120 | 2.6 | 289 | 4.3 | 43 | 3.7 | 452 | 3.5 |
| External | 1,678 | 36.4 | 1,223 | 18.0 | 162 | 13.9 | 3,063 | 14.0 |
| Other | 112 | 2.4 | 253 | 3.7 | 37 | 3.2 | 402 | 3.2 |
| Total | 4,612 | 100.0 | 6,780 | 100.0 | 1,162 | 100.0 | 12,554 | 100.0 |
*By number of injuries.
† % = percent of all injuries.
The most common injuries in the pediatric group, aside from abrasions and superficial injuries, involved the head and neck (34.6%), with musculoskeletal being the second most common (22.2%). In contrast, among adults, musculoskeletal injury (41.4%) was more common than head and neck injury (26.7%). Also among the elderly, musculoskeletal injury (40.0%) was more common than head and neck injury (31.0%). Within each age group, lower-extremity injuries occurred more often than upper-extremity injuries. Chest and abdominal injuries were less common than either head and neck or musculoskeletal injuries.
An operation was required in 11% of all patients. A total of 67% of the patients underwent orthopaedic procedures, 2% for thoracic, 11% for abdomen and pelvis, 46% for extremities, and 14% for other. For patients who underwent operative procedures, operation involving an extremity was most frequent (63.3%); procedures involving the spinal cord and spinal canal were least common (0.8%) (Table 4). Significantly (p<0.01) fewer pediatric patients (15.4%) required operation than adults (37.5%) or the elderly (37.3%). Head and neck injuries were less likely to require operation (9.3%) than chest (51.8%), abdominal (51.8%), or musculoskeletal injuries (52.6%).
Table 4. Operations: Anatomic Distribution
| Pediatric | Adult | Elderly | Total | |||||
| Location | n | % | n | % | n | % | n | % |
| Head and neck | ||||||||
| Intracranial | 54 | 8.1 | 168 | 6.6 | 52 | 13.9 | 274 | 7.7 |
| Face | 22 | 3.3 | 53 | 2.1 | 2 | 0.5 | 77 | 2.2 |
| Spine | 7 | 1.0 | 14 | 0.6 | 6 | 1.6 | 27 | 0.8 |
| Chest | 28 | 4.2 | 101 | 4.0 | 23 | 6.2 | 152 | 4.2 |
| Abdomen | 37 | 5.5 | 190 | 7.5 | 30 | 8.0 | 257 | 7.2 |
| Musculoskeletal | 382 | 57.3 | 1,675 | 66.0 | 207 | 55.5 | 2,264 | 63.3 |
| Other | 137 | 20.5 | 338 | 13.3 | 53 | 14.2 | 528 | 14.8 |
| Total | 667 | 100.0 | 2,539 | 100.0 | 373 | 100.0 | 3,579 | 100.0 |
Number of patients includes all patients who were admitted to the hospital and those who were seen only in the emergency room.
Blood alcohol status was recorded in 325 patients. Of those with a documented blood alcohol level, 85.2% had greater than 0.08%, which is the legal limit in California. Those with any blood alcohol detected had a higher ISS (12.7 ± 0.7 versus 10.8 ± 0.2; p<0.01) and a lower RTS (7.0 ± 0.01 versus 7.4 ± 0.01; p<0.01) than those without. No difference in the mortality rate was observed between those with and without blood alcohol detected.
Mortality was highest among the elderly (27.8%), followed by adults (8.1%) and children (3.1%) (p<0.01 for overall comparison; Table 5). Those patients who had a head injury had a higher mortality rate than those who did not (13.6% versus 4.8%; p<0.001).
Table 5. Mortality
| Measure | Pediatric | Adult | Elderly | Total |
| Mortality* (%) | 3.1 | 8.1 | 27.8 | 7.7 |
| ISS | ||||
| Lived | 6.1 ± 0.2† | 7.5 ± 0.2† | 8.3 ± 0.5† | 7.0 ± 0.1† |
| Died | 27.6 ± 2.7 | 25.0 ± 1.3 | 22.1 ± 1.7 | 24.5 ± 1.0 |
| RTS | ||||
| Lived | 7.6 ± 0.01† | 7.5 ± 0.02† | 7.7 ± 0.03† | 7.6 ± 0.01† |
| Died | 3.7 ± 0.3 | 4.4 ± 0.2 | 5.7 ± 0.2 | 4.7 ± 0.1 |
| GCS | ||||
| Lived | 14.2 ± 0.1† | 13.9 ± 0.1† | 14.3 ± 0.1† | 14.0 ± 0.03† |
| Died | 4.0 ± 0.4 | 5.8 ± 0.3 | 8.2 ± 0.5 | 6.2 ± 0.2 |
* p<0.01 for overall comparison of the three age groups.
† p<0.001 between survivors and nonsurvivors in each age group.
GCS, Glasgow Coma Scale; ISS, Injury Severity Score; RTS, Revised Trauma Score.
Nonsurvivors had a higher ISS (24.5 ± 1.0 versus 7.0 ± 0.1; p<0.001), a lower RTS (4.7 ± 0.1 versus 7.6 ± 0.01; p<0.001), and a lower GCS (6.2 ± 0.2 versus 14.0 ± 0.03; p<0.001) than survivors in each age group. There were 1,033 patients for whom the ISS was either zero or unavailable, in part because of patients with either minor injuries or without ISS recorded. Recalculation of the population ISS without these 1,033 patients produced an overall ISS higher than that previously computed (10.5 ± 0.2 versus 8.3 ± 0.1). Despite these ISS values, the relative outcomes among the age groups were not affected.
At the time of discharge, 78% of the patients had a temporary disability, 4% had a permanent handicap, and only 16% were functioning at preadmission capacity. Among those with an identifiable payer source, 45% were state or federal, 25% were cash or self-pay (indigent), 18% belonged to an HMO or had a group carrier, and 12% were compensated by other sources.
Introduction | Methods | Results | Discussion | References