Old age is a risk factor for poor outcome in trauma patients, as a result of undertriage and the presence of occult life-threatening injuries. The mechanisms of injury for geriatric trauma differ from those in younger patients, with a much higher incidence of low-impact trauma, especially falls from a low height. Frailty is a risk factor for severe injury after minor trauma, and caring for these patients require a multidisciplinary team with both trauma and geriatric expertise. With early recognition and aggressive management, severe injuries can still be associated with good outcomes, even in very elderly patients.
Key points
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Geriatric trauma is different in terms of mechanisms of injury and injuries sustained, which leads to delays in diagnosis and treatment.
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In the geriatric patient, low-impact trauma can be associated with severe injury.
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Elderly trauma patients can have good outcomes with high quality of life, with early interventions and prevention of complications.
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Standard trauma care is based on evidence where the elderly are underrepresented.
What is geriatric trauma and why does it matter?
Trauma is traditionally considered a disease of young men after motor vehicle collisions and interpersonal violence. The acute trauma chain of care has been organized to identify and transport the severely injured patient to high-level trauma centers for life-saving interventions. This strategy has been highly effective, positively impacting the traditional trimodal distribution of mortality (immediate, early, and late) through early recognition and treatment of life-threatening conditions to reflect fewer early and late deaths.
Just as trauma care evolves, so does the population of traumatically injured patients. As life expectancy increases, geriatric patients are more likely to suffer significant injuries later in life. The typical geriatric trauma patient, however, is distinctly different from the typical young and healthy male involved in high risk activities. Geriatric trauma patients are more likely to be female, have multiple comorbidities, and be described as “frail”: a biologic syndrome of decreased reserve and resistance to stressors, resulting from cumulative declines across multiple physiologic systems. Frailty is a condition that requires a multidisciplinary team effort to prevent deterioration and adverse outcomes after injuries or illnesses that would not otherwise pose serious health threats to nonfrail patients.
The frail geriatric patient who has fallen from standing does not succumb to exsanguination during the golden hour of trauma, but rather dies of pneumonia in the recovery phase or enters the trajectory of rapid functional decline after a hip fracture.
Elderly patients with both low- and high-energy trauma are less likely than younger patients to be sent to a trauma center, despite their higher rates of poor outcomes. New recommendations attempt to address this discrepancy by directing more elderly patients to advanced trauma care. To optimize outcomes, accurate risk stratification, evidence-based treatment options, and clear goals of care are needed. Even among elderly patients, different priorities exist depending on age, frailty, and mechanism of injury. The 94-year-old nursing home patient who fell out of bed is distinctly different from the 67-year-old motorcyclist injured in a crash, even though they both may have sustained life-threatening injuries.
What is geriatric trauma and why does it matter?
Trauma is traditionally considered a disease of young men after motor vehicle collisions and interpersonal violence. The acute trauma chain of care has been organized to identify and transport the severely injured patient to high-level trauma centers for life-saving interventions. This strategy has been highly effective, positively impacting the traditional trimodal distribution of mortality (immediate, early, and late) through early recognition and treatment of life-threatening conditions to reflect fewer early and late deaths.
Just as trauma care evolves, so does the population of traumatically injured patients. As life expectancy increases, geriatric patients are more likely to suffer significant injuries later in life. The typical geriatric trauma patient, however, is distinctly different from the typical young and healthy male involved in high risk activities. Geriatric trauma patients are more likely to be female, have multiple comorbidities, and be described as “frail”: a biologic syndrome of decreased reserve and resistance to stressors, resulting from cumulative declines across multiple physiologic systems. Frailty is a condition that requires a multidisciplinary team effort to prevent deterioration and adverse outcomes after injuries or illnesses that would not otherwise pose serious health threats to nonfrail patients.
The frail geriatric patient who has fallen from standing does not succumb to exsanguination during the golden hour of trauma, but rather dies of pneumonia in the recovery phase or enters the trajectory of rapid functional decline after a hip fracture.
Elderly patients with both low- and high-energy trauma are less likely than younger patients to be sent to a trauma center, despite their higher rates of poor outcomes. New recommendations attempt to address this discrepancy by directing more elderly patients to advanced trauma care. To optimize outcomes, accurate risk stratification, evidence-based treatment options, and clear goals of care are needed. Even among elderly patients, different priorities exist depending on age, frailty, and mechanism of injury. The 94-year-old nursing home patient who fell out of bed is distinctly different from the 67-year-old motorcyclist injured in a crash, even though they both may have sustained life-threatening injuries.
Age as a risk factor in trauma: when do you get old?
Several studies have shown that trauma in the geriatric population is associated with increased acute and long-term mortality.
Advancing age is an independent predictor of mortality after trauma; however, there is no well accepted threshold or cutoff for what constitutes a “geriatric” patient nor is there a definite cutoff that accurately predicts outcome. Various age values have been proposed, ranging between 45 and 80. Adams and colleagues found that age 45 years and older was associated with increased mortality after trauma, whereas Pandya and colleagues found a significant increase in mortality among patients 55 years and older involved in motor vehicle collisions. Other studies found an increased mortality in patients older than 60 years and 65 years of age. In a cross-sectional study of 75,658 trauma patients, Caterino and colleagues found a threshold value of 70 to 74 years for mortality rate stratified by Injury Severity Score (ISS). The range of cutoffs are more likely related to study limitations or statistical nuances than inherent differences among the study populations. These studies simply highlight the importance of advanced age on morbidity and mortality after trauma.
Interestingly, Friese and colleagues found that the risk of death after injury is proportional to patient age until 84 years, after which the mortality rates actually decline. This trend may be related to survivor bias, whereby a greater proportion of those living past 84 years of age are in better health, contributing to this somewhat paradoxic finding. A study by Adams and associates suggests that variance in mortality for younger and older trauma patients was minimal (4%–7%) after patients with active do not resuscitate orders were excluded from analysis.
The elderly are not just old adults: frailty as a risk factor
Elderly patients have a higher incidence of medical comorbidities and lower physiologic reserves, increasing their susceptibility to even minor trauma. In fact, age may be an overly simplistic measure to understand outcomes in geriatric trauma patients and better predictor may be the degree of frailty.
Frailty is composed of both the degree of loss of physiologic reserve and increased incidence and severity of comorbid disease. Biologically, this translates to musculoskeletal, neuroendocrine, nutritional, and immunologic defects that contribute to a physical state of muscular weakness and other functional impairment.
Frailty is an independent predictor of postoperative complications, mortality, and hospital duration of stay in elderly patients undergoing emergency general surgery. Frail elderly patients not only have higher in-hospital mortality, but also suffer from poorer long-term outcomes compared with their nonfrail counterparts. For example, frail elderly patients have a decreased functional ability 1 year after a fall and an increased mortality risk that persists 3 years after the event. Frailty before hip fracture is associated with greater postfracture pain and deterioration in function and preinjury frailty is the predominant predictor of postinjury functional status and mortality.
The role of frailty and preinjury functional status in predicting outcomes after trauma is profound. Dunham and colleagues concluded that, although frailty was an independent predictor of discharge to a long-term care facility after trauma, dementia and multiple comorbidities were not.
Several instruments have been designed to quantify frailty. The Trauma Specific Frailty Index was derived from the complex, 50-variable Frailty Index, simplified to improve clinical usefulness. The Trauma Specific Frailty Index has been shown to an independent predictor of unfavorable discharge disposition in geriatric trauma patients and in-hospital complications.
In a prospective study of 368 consecutive trauma patients admitted to a level 1 trauma center, frailty (as assessed by the Trauma Specific Frailty Index) increased the risk of death from a major complication by almost 3-fold. Nearly 7 in 10 patients who died from a major complication were identified as frail, despite representing only 25% of the study cohort. Frail patients were also less likely to be discharged home (22% vs 72%), suggesting that many survivors suffered significant and permanent functional impairment as a result of their injury.
In summary, there is significant variation in the health status of elderly people that warrants individualized considerations based on frailty rather than age. Frailty is not a treatable condition, but rather a risk factor that needs to be identified to prevent complications, both in the hospital and after discharge. We suggest that all hospitals caring for injured elderly patients ensure that frailty is assessed and managed by a multidisciplinary team of health care providers with expertise in geriatrics.
Mechanism of injury: how do old people get hurt?
Falls are the most common cause of injury in the elderly. When nonelderly patients fall, more than 90% fall on one or both hands outstretched, reducing the impact to the hip and head. In contrast, elderly patients are less likely to protect themselves when falling and only 33% to 50% fall on outstretched hands, with women being less likely to do so than men. Also, the upper extremities of elderly women have nearly one-half the capacity of younger women to absorb the energy generated by a fall.
Motor vehicle collisions are a common cause of serious injury in the elderly population. Elderly patients, especially females, are more susceptible to seatbelt–induced thoracic trauma from low or moderate speed crashes. Thoracic injuries are associated with increased mortality in women age 65 years and older. Patients age 60 and over have a 3-fold risk of blunt thoracic aortic injury when involved in motor vehicle accidents. The presence of multiple rib fractures, even in isolation, has been shown to increase mortality owing to secondary pulmonary and cardiac complications.
The elderly pedestrian is especially vulnerable and overrepresented among fatalities. In the United States, 20% of all pedestrian fatalities are 65 years of age and older ; in the European Union, nearly one-half of pedestrian fatalities are in the geriatric population (available: www.erso.eu ).
Age-related differences in injury severity are not fully accounted for by mechanism alone. According to Henry and colleagues, pelvic fractures in the elderly are “a different entity” than those typically observed in younger patients. Elderly patients are more likely to suffer lateral compression fractures, an injury pattern often considered less severe than anteroposterior compression fractures. Despite this, elderly patients have higher rates of pelvic bleeding requiring blood transfusions and a greater need for angiographic treatment.
In addition to different patterns of injury, the same injury often results in worse outcomes in elderly patients. Clavicle fractures are associated with a surprisingly high mortality rate in patients over 65 years of age who have sustained high-impact trauma. Elderly patients are also more likely to have massive bleeding where the source is not recognized during the primary survey, including retroperitoneal hematoma and stable pelvic ring fractures.
Vital signs: maybe not so vital in the elderly
In trauma patients, abnormal vital signs correlate positively with patient mortality. Traumatic hemorrhage is associated with decreased systolic blood pressure (SBP), increased heart rate (HR) and an increased Shock Index (HR divided by SBP ). However, the role of individual vital signs in predicting mortality and morbidity in geriatric trauma patients is complex, and normal vital signs are not as reassuring as they might be in younger patients.
Heffernan and colleagues conducted a retrospective study of 5000 patients, comparing young (17–35 years of age) and elderly (65 years and older) patients with major trauma. They concluded that mortality was significantly higher among elderly patients with HR of greater than 90 bpm. In contrast, only a HR of greater than 130 bpm was associated with increased mortality in young patients. Mortality significantly increased with a SBP of less than 110 mm Hg among geriatric patients, whereas similar outcomes were not observed until the SBP decreased to less than 95 mm Hg in young patients. In addition, a U-shaped association between HR, SBP, and mortality was observed. Discrepant vital sign cutoffs were also observed in patients with occult shock. Taken together, the literature highlights the importance of age-adjusted vital sign cutoffs to identify patients in need of aggressive resuscitation. Based on available evidence, we suggest that hypotension be defined as a SBP of less than 110 mm Hg in the geriatric population.
Emergency department triage relies heavily on vital signs upon arrival. The lack of reliable vital sign cutoffs for elderly trauma patients complicates this process. Therefore, elderly trauma patients are at risk for being undertriaged, resulting in delays to injury recognition and management.
Vital signs have been proposed to predict the need for massive transfusion among trauma patients of all ages. The predictive power of HR for massive transfusion among geriatric trauma patients has been questioned. In 1 study, SBP, pulse pressure, diastolic blood pressure, and shock index (SI) were all strongly predictive of massive transfusion, whereas HR was not. This may reflect, in part, the higher rates of cardiac medications among geriatric patients, limiting the expected tachycardic response to massive hemorrhage. Similarly, Ohmori and colleagues found that only SI was predictive of the need for massive transfusion, whereas blood pressure, HR, and Glasgow Coma Scale score were not useful.
The need to predict more precisely massive transfusion and mortality among geriatric trauma patients has resulted in the age shock index (age × SI). This has been shown superior to both vital signs alone and unadjusted SI for predicting both mortality and need for massive transfusion among injured elderly patients.
Who is sick and who is not: shock identification among injured elderly
In severe traumatic injury, severe hypovolemia can lead to inadequate organ perfusion, ischemic injury, and tissue hypoxia. This in turn creates a metabolic acidosis that manifest as increased base deficit (BD) and elevated serum lactate. Serum lactate is a direct measure of anaerobic metabolism, whereas a BD is a calculated value of the amount of base required to achieve a neutral pH, assuming a normal P co 2 .
The usefulness of BD to characterize the presence and extent of hemorrhagic shock in trauma patients has been studied in younger populations, where BD correlates with transfusion requirements, duration of stay in the intensive care unit (ICU), and all-cause mortality. Contrastingly, only a handful of studies have specifically investigated the use of BD in geriatric trauma. Initial BD measurements performed similarly to serum lactate in mortality prediction; however, lactate was a superior predictor of injury severity and in-hospital mortality.
Both BD and serum lactate have important limitations. Lactate levels may be affected by alcohol consumption, and BD may be altered by minute ventilation or intravenous fluids. There is no strong evidence that either measure is superior for shock identification or clinical prognostication. Instead, recent guidelines support the use of either measure as a sensitive test to estimate the degree of hemorrhagic shock.
BD and serum lactate can assist in identifying occult shock, a state of hypoperfusion that lacks obvious clinical disturbances or vital sign abnormalities. This “cryptic” form of shock is especially common in geriatric patients, occurring in 16% to 70% of major trauma victims. The high incidence of occult hypoperfusion in this patient population can be explained in part by decreased physiologic reserves (or frailty), medical comorbidities, and medications. Occult shock is associated with an increase in trauma-related mortality from 12% to 35% when hypoperfusion persists for more than 12 hours.
Although modified triage and resuscitation guidelines that account for occult shock have been developed, they have not gained widespread use.
In summary, current data suggest that both BD and serum lactate represent important biomarkers for shock and occult shock, and should be considered predictors of serious or severe injury in geriatric patients, even when physical examination and vital signs are nonspecific.
Trauma centers for the elderly, or geriatric care for the injured?
Retrospective cohort studies have shown that elderly patients who are treated at trauma centers fare better than those seen at nontrauma centers. Which elderly patients require transfer remains a considerable challenge, with several studies demonstrating higher rates of undertriage in this population.
New guidelines for field triage of injured patients have attempted to address the issue of undertriage for elderly patients. The 2011 American College of Surgeons Committee on Trauma guidelines included special considerations for older adults, including the following.
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Risk of injury and death increases with age.
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SBP of less than 110 mm Hg results in worse outcomes and may represent a shock state.
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Low-impact mechanisms (eg, ground-level falls) can cause serious injury.
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Trauma triage instruments have poor discriminatory properties for the elderly. Newgard and colleagues found that using broader cutoffs for vital signs (Glasgow Coma Score ≤14, SBP ≤110 or ≥200, respiratory rate ≤10 or ≥24 per minute or HR ≤60 or ≥110 bpm) could increase triage sensitivity for seriously injured geriatric patients at the expense of specificity. Implementation of these criteria pose marked resource and logistical challenges, because an additional 46 patients without serious injuries would need to be transported to a trauma center to identify only 1 with serious injuries (ISS >15).
The adoption of new geriatric trauma center criteria in Ohio ( Box 1 ) increased the number of patients aged 70 and over who qualified for trauma center care from 44% to 58%. Despite this, incorporating the revised criteria into the emergency medical services training program only resulted in a 1% increase in initial transportation to a trauma center.
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Glasgow Coma Scale score of <14 in the presence of known or suspected traumatic brain trauma.
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Systolic blood pressure of <100 mm Hg.
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Fall from any height with evidence of traumatic brain injury.
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Multiple body system injuries.
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Struck by a moving vehicle.
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Presence of any proximal long bone fracture after motor vehicle trauma.
Given the challenges associated with predicting injury severity in the elderly, overtriage is an inevitable outcome of setting low and broad criteria for transporting these patients to a trauma center. A recent analysis of trauma registries in the United States suggests not only an increasing number of elderly patients, but also a high proportion of patients with minor injuries are being preferentially transported to trauma centers. Bradburn and colleagues found that 52% of patients admitted to a regional trauma hospital had an ISS of less than 10, suggesting a trend toward admitting patients with less severe injuries.
Overtriage to trauma centers not only carries a substantial cost, but may result in harm to patients who forgo necessary geriatric care in favor of more focused trauma management. In centers with high volumes of geriatric trauma patients, these risks can be mitigated; however, it requires efforts and investment to centralize geriatric trauma care. Zafar and colleagues found that risk-adjusted death from a complication rates declined from 25% to 20% when going from centers with less than 10% to greater than 50% geriatric trauma. The incidence of major complications did not change significantly, suggesting that reported differences in mortality were not likely to be explained by differences in complication rates. Considering the complexity of trauma triage, clinical pathways for injured elderly patients are needed at all hospitals that see acutely ill patients.
Trauma team activation
The severity of injuries among elderly patients is consistently underestimated and the elderly benefit from more liberal criteria for trauma team activation (TTA). In 1 study of 883 elderly trauma patients, only 25% of patients met at least one of the standard TTA criteria. Despite this, mortality was 50% and ICU admission was 39%. More impressively, among severely injured patients (ISS >30), 25% did not meet any TTA criteria. TTA criteria included traditional vital sign abnormalities (SBP <90 mm Hg, HR >120 bpm, respiratory rate <10 or >29 breaths/min, unresponsive to pain, thoracoabdominal gunshot wound). These results highlight how insensitive traditional measures of shock are in the geriatric population, and that more liberal criteria for TTA are warranted. The authors conclude that patients age 70 years and older should be a criterion for TTA, irrespective of physiologic status at the time of assessment. Whether this represents the best use of resources remains to be seen, but suffice it to say that more nuanced considerations of age or frailty should likely be studied.
Rehn et al studied TTA in Norway where patients over 70 years of age were found to be 5 times more likely to be undertriaged. A study of elderly patients by St John and colleagues found that elderly patients with severe injury were less likely to result in TTA, but also that TTA activation in elderly patients over 65 years of age was not significantly associated with a reduced risk of poor outcomes. Younger patients, however, had a clear benefit of TTA (odds ratio, 0.48).
The retrospective design of these studies makes it difficult to assess which elderly patients would benefit from TTA. The patients with poor outcomes who are likely to be missed by current TTA criteria are older and have fewer clinical signs and symptoms, but the optimal management for these patients remains to be established. The Eastern Association for the Surgery of Trauma Flow Diagram for the injured elderly patient offers a systematic approach to initial decision making ( Fig. 1 ).
