Chapter 45 Geriatric Trauma

The Impact of Trauma

The number of Americans aged 65 years and over is expected to increase from the current level of 36.3 million to 86.7 million by 2050.¹ Trauma, once considered predominately a disease of the young, has long been the leading cause of death in the United States for individuals between the ages of 1 and 44 years.² Although the incidence of major traumatic injury remains lower in the geriatric population than in any other group, dramatic longevity gains and increasingly active lifestyles have contributed to rising injury rates among senior citizens.³ In some areas of the United States, the number of elderly women hospitalized for injury now exceeds that of young men.⁴ These trends are substantially altering long-standing patterns of injury demographics. More than 900,000 seniors require hospitalization for trauma each year, and half of these patients have one or more fractures.⁵ As the population continues to age, trauma care providers need to be cognizant of these trends and shift care to match.

There are significant differences between older and younger patients related to both injury patterns and the frequency and type of complications experienced following trauma. Despite a typically less severe mechanism of injury, older adults experience a greater number of post-injury complications than do their younger counterparts.

In older adults, poor outcomes following traumatic injury are related to both the normal changes of aging and the prevalence of preexisting comorbid conditions. As a consequence of reduced physiologic reserves and chronic disease, injured geriatric patients are hospitalized for trauma at a rate twice that of the general population.⁶ On average, trauma care expenditures for geriatric patients are two and a half times those for younger individuals.⁶ These higher costs are attributed to greater frequency and duration of critical care admissions, an increased number of complications, and overall longer hospital stays.⁷ It is difficult to determine whether the incidence of trauma is a surrogate for preexisting fragility in the elderly or the actual cause of decline, but studies of isolated single-system trauma in older individuals have documented serious outcomes after injuries as minor as a closed radial fracture.⁸

The incidence of fatal injury increases markedly with aging. Trauma is the eighth leading cause of mortality in those over the age of 55 years and the ninth most common cause of death in persons 75 years and older.⁹ Although seniors comprise only 12.5% of the population, almost one third of injury deaths occur in the 65-years-plus age group.⁶ Following major trauma, geriatric patients experience in-hospital mortality rates two to six times greater than younger adults with equivalent injuries.¹⁰ Even minor trauma may result in substantial mortality among older adults.

Barriers to Trauma Care in the Older Adult

Researchers examining prehospital data have identified high rates of geriatric trauma center undertriage compared to younger adults. A statewide Pennsylvania study found that 47% of younger patients were correctly identified in the field and triaged to a designated trauma center but only 36% of those over age 65 years were triaged to the appropriate level of care.¹¹

In-hospital trauma team activation criteria (e.g., heart rate >100 beats per minute; systolic blood pressure <90 mm Hg) are not sensitive to the physiology of injured elders. Seniors often fail to exhibit the same vital signs, symptoms, and pain levels found in their younger counterparts.⁶

Trauma team activation criteria have been deliberately selected to overtriage patients in order to avoid missing those in need of special care. However, one study documented 16% mortality among geriatric trauma patients who failed to meet even a single activation criterion and an alarming 50% mortality in those who met only one.¹² Such findings have prompted some authors to argue that older individuals with apparently minor or moderate injuries should be initially triaged as trauma patients and given the benefits of full trauma team activation at a designated center.¹²

Mechanisms of Injury

Falls

Falls, most of which occur at home, are the leading trauma mechanism among persons over age 65 years.⁶^,⁹ In this population even low-energy, same-level falls frequently produce significant fractures, craniocerebral trauma, and visceral injury. In the 75-years-plus age group, falls outnumber motor vehicle crashes as the primary cause of traumatic death.² Many factors associated with aging contribute to the high incidence of falling:

Motor Vehicle Crashes

Currently, motor vehicle crashes account for 21.5% of injuries in the geriatric population,⁹ but this number is likely to climb. By 2020, the number of drivers in the United States over age 65 years will total 33 million.¹⁰ Age-related declines in cognitive function, decreased auditory acuity, changes in direct and peripheral vision, impaired coordination, limited neck mobility, and increased reaction time all contribute to crashes involving elderly motorists.⁷ Although the annual number of miles driven decreases after age 55 years, seniors have a total motor vehicle crash rate second only to that of 16- to 25-year-olds.⁶ Unfortunately, the elderly (particularly those 75 years or older) sustain a post-crash fatality rate greater than any other age group.¹³

In contrast to younger motorists, seniors are more likely to crash during daylight hours, in good weather, and close to home. Older adults are also more prone to crashes involving another vehicle, intersections, left turns, traffic sign violations, and right-of-way decisions. Yet, compared to younger cohorts, the older driver is less likely to have ingested alcohol.⁶