Authors

The EAST Practice Management Guidelines Work Group:

David G. Jacobs, MD, Committee Co-Chair, Carolinas Medical Center, Charlotte, NC
Brian Ray Plaisier, MD, Committee Co-Chair, Bronson Hospital, Kalamazoo, MI
Philip S. Barie, MD, NYH – Cornell Medical Center, New York, NY
Jeffrey S. Hammond, MD, Robert Wood Johnson Medical School, New Brunswick, NJ
Michele R. Holevar, MD, Mt. Sinai Hospital, Chicago, IL
Karlene E. Sinclair, MD, Morehouse School of Medicine, Atlanta, GA
Thomas M. Scalea, MD, University of Maryland Medical Center, Baltimore, MD
Wendy Wahl, MD, University of Michigan Health System, Ann Arbor, MI 

Introduction

Advanced age is a well-recognized risk factor for adverse outcomes following trauma. A substantial body of literature, much of it cited within this document, demonstrates increased morbidity and mortality in geriatric trauma patients compared to their younger counterparts. Whether this outcome difference is due to the decreased physiologic reserve that accompanies aging, a higher incidence of pre-existing medical conditions in the geriatric patient, or to other factors yet to be identified, remains unclear. It is clear, however, that good outcomes can be achieved in this patient population when appropriately aggressive trauma care is directed towards geriatric patients with survivable injuries. Implicit in the above statement is the need to identify, as soon as possible following injury, those patients who will benefit from aggressive resuscitation, timely injury management, and post-trauma rehabilitation. It is equally important, however, to limit these intensive and expensive treatment modalities to patients whose injuries are not only survivable, but are compatible with an acceptable quality of life.

Our purpose in developing this guideline was to provide the trauma practitioner with some evidence-based recommendations that could be used to guide decision-making in the care of the geriatric trauma patient. We began this process by first developing a series of questions, the answers to which we hoped could be supported by the existing scientific literature. The initial set of questions were as follows:

1. Is age itself a marker of increased morbidity/mortality? If so, what age should be used?
2. Is age instead a surrogate for increased pre-existing conditions (PEC’s)? If so, which premorbid conditions are particularly predictive of poor outcomes?
3. Should age itself be a criterion for triage from the field directly to a trauma center, regardless of Glasgow Coma Scale (GCS) score, trauma score (TS), etc.? If so, what age should be used?
4. Do trauma centers have better outcomes with geriatric trauma than non-trauma centers?
5. Are there specific injuries, scores [Injury Severity Score (ISS), TS, GCS, etc], or PEC/age combinations in geriatric trauma patients that are so unlikely to be survivable that a nonaggressive approach from the outset could be justified?
6. What resuscitation end-points should be used for the geriatric trauma patient?
7. Should all geriatric trauma patients receive invasive hemodynamic monitoring? If so, what specific types of monitoring should be used? If not, which geriatric patients benefit from invasive monitoring?
8. Are there specific types of therapies that should be employed routinely in trauma patients (e.g. ß- blockade, nitroglycerin infusions, etc.)?
9. How are outcomes measured in geriatric trauma? Which specific outcome measures should be used?

Unfortunately, after examining the available literature, it is clear that evidence-based responses to all of the questions raised above are not possible. As the accompanying evidentiary tables demonstrate, there are a few, if any, prospective, randomized, controlled trials which definitively address any of the above issues. Secondly, there is a lack of uniformity as to a specific age criterion for geriatric trauma. As shown in the accompanying evidentiary table, geriatric trauma is variously defined in the literature as age greater than or equal to 55, 60, 65, 70, 75, and even 80 years of age. There is even literature support for increased mortality from trauma beginning at age 45! Furthermore, since age is a continuous variable, and not a dichotomous one, adverse outcomes associated with geriatric trauma are likely to increase in a © Copyright 2001 Eastern Association for the Surgery of Trauma 3 continuous fashion which age as opposed to a stepwise leap as a given patient reaches a specific age. Third, there is no consise definintion of a geriatric trauma patient. In some studies, all patients over a given age are included, whereas in others, patients with penetrating injuries, burns, and those with minor injuries, such as slip-and-falls, are excluded. Some studies include all patients regardless of hemodynamic instability or injury severity, while others impose strict entrance criteria or exclude patients who do not survive for a predetermined period of time following admission. Such lack of uniformity with regards to inclusion criteria makes it difficult to compare outcomes across different patient populations. Finally, much of the literature concerning geriatric trauma is relatively “old”, that is, published more than 10 years ago. Given the significant improvements in patient care which have occurred over the past 10 to 20 years, recommendations based upon outcomes achieved more than 10 years ago may not be applicable to today’s geriatric trauma patient.

Despite the above-mentioned shortcomings, our committee still felt that it was important to summarize the available literature and make evidence-based recommendations where satisfactory evidence did exist. In light of the nine questions raised above, three broad areas of focus emerged within this guideline: Issues of Geriatric Trauma Triage, Issues of Geriatric Trauma Resuscitation, and Issues of Outcome Measurement in Geriatric Trauma. Although there was considerable overlap among these three areas, each issue has been addressed separately within this guideline and, accordingly, three separate “sub-guidelines,” each with its own recommendations, evidentiary table, and areas for future research, comprise this practice management guideline for geriatric trauma. It is hoped that the information provided within these three sub-guidelines, will provide evidence-based support for the difficult decisions which are required to achieve optimal outcomes in this difficult, but ever increasing, patient group. 

I. Statement of the problem

There is no doubt that the elder trauma patient presents trauma surgeons with a complex challenge. The effects of aging upon individual organ systems and the presence of comorbid conditions combine to create a milieu that does not allow for errors in resuscitation or delays in diagnosis. It is widely known that geriatric patients have less physiologic reserve than younger patients and that mortality rates are higher than in a younger cohort. There is a growing sentiment that the conduct of resuscitation for the inured elder must be undertaken with an aggressive and thoughtful approach. Outcome data suggests that the elderly benefit by an aggressive approach to resuscitation. It is believed by some that the pulmonary artery catheter should be a routine part of the resuscitation process for the severely injured geriatric patient. In addition, there are certain laboratory assays that have been recommended for use in this clinical scenario. There is confusion, however, regarding end-points for resuscitation and which patients benefit from invasive hemodynamic monitoring.

II. Process

Literature used for these guidelines was obtained via a search of the MEDLINE database from the National Library of Medicine. Citations in the English language during the period of 1966 through 1999 using the words elderly, geriatric, trauma, shock, and resuscitation were identified. Citations concerned primarily with multisystem trauma or single organ injury in a multisystem context were utilized. Additional non-trauma references were used to relate epidemiological or physiologic factors concerning the geriatric patient to the context of potential injury. This search identified 4,783 references. For use in the evidentiary table, these were then sorted in order to identify articles associated with geriatric trauma patients exclusively. The bibliographies of each article were searched for additional references not identified by the original MEDLINE query. Letters to the editor, case reports, review articles, and series examining non-trauma patients were excluded for use in the evidentiary table. The references were classified by methods employed by the Canadian and U. S. Preventative Task Force. Classification of references was graded based on the strength of the scientific evidence. For purposes of practice management guidelines for trauma, data were classified as follows: Class I evidence: Prospective randomized controlled trials (PRCTs) - the gold standard of clinical trials. Some may be poorly designed, have inadequate numbers, or suffer from other methodological inadequacies, and thus may not be clinically significant. Class II evidence: Clinical studies in which the data were collected prospectively, and retrospective analyses which were based on clearly reliable data. These types of studies include observational studies, cohort studies, prevalence studies and case control studies. Class III evidence: Most studies based on retrospectively collected data. Evidence used in this class includes clinical series, databases or registries, case reviews, case reports, and expert opinion.

III. Recommendations

A. Level I

There are insufficient data to support a level I recommendation for the method and end-points of resuscitation in the elderly patient as a standard of care.

B. Level II

1. Any geriatric patient with physiologic compromise, significant injury (AIS > 3), high risk mechanism of injury, uncertain cardiovascular status, or chronic cardiovascular or renal disease should undergo invasive hemodynamic monitoring using a pulmonary artery catheter.

There are insufficient data to support a level II recommendation for the method and end­points of resuscitation in the elderly patient as a standard of care.

C. Level III

1.  Attempts should be made to optimize to a cardiac index ? 4 L/min/M^[2]  and/or an oxygen consumption index of 170 cc/min/M^[2] .
2.  Base deficit measurements may provide useful information in determining status of resuscitation and risk of mortality.

IV. Scientific Foundation

It is widely known that the citizenry of the U.S. is continuing to age.^{[1] [2] [3]}  The elderly population (65 years and older) increased 11-fold from 1900 to 1994, while the segment under the age of 65 increased only 3-fold during the same period.^[2]  Data from the United States government shows that the life expectancy of the U.S. population reached 76.5 years the highest at any time in U.S. history.^[1]  There will be a dramatic increase in the elderly population due to the aging of the “baby-boom” generation (75 million babies born between 1946 and 1964).^[2] While projection assumptions vary, using the Census Bureau’s “Middle Series” projections (moderate fertility, mortality, and immigration assumptions) the elderly will make up 12.8% by 2000 and 20.4% by 2050.^[2]

Trauma ranks as the fifth leading cause of death when considering all races, both sexes, and all ages.^[1]  For years 65 and over, trauma ranks seventh, although the rate per 100,000 is 92.1 compared with 35.7 for all age groups. Unlike younger age groups, there is relatively little variation in death rates between black and white races. These data indicate that in the future there will be an unprecedented number of elderly persons at risk for injury.

Advancing age is associated with a gradual decline in organ function. Problems due solely to senescence and diseases not associated with age may be difficult to distinguish from one another, but it is important to account for all disorders concomitant with the injury. The walls of the heart become less compliant and cardiac index decreases 1% per year with age while systemic vascular resistance rises 1% per year.^[4]  Maximum heart rate is also reduced with age. In addition, the heart is less able to respond to the stress of injury as there is an age-related decrease in the effectiveness of adrenergic stimulation.^[5] The prevalence of hypertension also increases as a function of age. In the United States, 59.2% of white males aged 65-74 are hypertensive and this increases dramatically to 82.9% in elderly black females.^[6]  The end result of these age-related changes is a decreased ability to respond to the stress of injury or critical illness.

There are numerous changes in respiratory function with increasing age. The chest wall becomes less compliant and the elasticity of the lung decreases.^[4]  The loss of compliance results in a greater dependence on diaphragmatic breathing.

Renal mass is rapidly lost after the age of 50 and a corresponding fall in glomerular filtration rate occurs beyond the age of 60 due to the loss of nephrons.^[4]  Measurement of creatinine clearance becomes more important in the geriatric patient, since serum creatinine may be lowered as a result of decreased muscle mass, giving a false sense of security with respect to renal function. Age-related vascular changes result in a decreased percentage of blood flow to the older kidney.^[4]

Endocrine function is also seen with advancing age. The production and turnover of thyroid hormone species is significantly reduced.^[7]  Tissue responsiveness to thyroid hormone is lessened, resulting in striking similarities between clinical hypothyroidism and the changes commonly seen in the elderly as a result of senescence.^[7] Normal adrenal function is critical in order to respond to the stress of injury and critical illness. Basal, circadian, and stimulated cortisol secretion remains intact with aging.^[8]  There is an age-related decrease in the catabolism of cortisol, although this is compensated with a decrease in the rate of catabolism.

The question of whether or not preexisting disease contributes to poor outcome has not yet been conclusively answered. The prevalence of comorbid conditions in trauma patients is between 8.8% and 19.3%.^[9]  In injured patients greater than 65 years however, the incidence climbs to 30%.^[10] Milzman found that by 75 years, 69% of patients had one or more pre-existing conditions.^[11]  Smith et al. found at least one comorbidity in 61.6% of patients in their series.^[12]  In a study of 102 patients from Switzerland admitted with femur fractures, 16% presented with a single comorbid condition, 45% presented with two comorbid conditions, 28% with three conditions, and 11% presented with four.^[13]  Battistella found an average of two pre-existing medical problems in injured patients 75 years and older.^[14]  After controlling for age, Sacco found that hepatic, cardiovascular, respiratory, renal, and diabetes adversely affected survival.^[15] Milzman and MacKenzie found that mortality and length of stay increased as the number of pre­existing conditions rose.^{[11] [16]}

Criteria for hemodynamic monitoring are not clear in this population. The gravity of this situation is underscored since it has been found that the elderly patient is more likely to present in shock than younger patients with similar trauma and injury severity scores.^[17] In geriatric patients undergoing elective surgery, occult physiologic compromise has been shown to contribute to poor outcome. DelGuerico found significant physiologic compromise in geriatric patients who had been “cleared” for elective surgery.^[18]  Among those who were not able to be optimized prior to surgery, all died postoperatively. Similar work has also been done in trauma patients.

Scalea et al. found significant measurable hemodynamic compromise in elderly patients who were clinically stable after initial evaluation after blunt multiple trauma.^[19]  Based upon institutional experience, criteria were developed to select patients for invasive hemodynamic monitoring. These criteria included: pedestrian-motor vehicle mechanism, initial blood pressure < 150 mm Hg, acidosis, multiple fractures, and head injury. Patients were moved to the intensive care unit as quickly as possible. Pulmonary artery catheters and arterial lines were inserted in all patients. Volume infusion and ionotropes were used to augment hemodynamic parameters. Attempts were made to optimize patients to a cardiac index ? 4 L / min / M^[2]  or an oxygen consumption index of 170 cc / min / M^[2] . Thirteen of 30 patients were found to be in cardiogenic shock and 54% of these died. There were statistically significant differences between optimized cardiac output and systemic vascular resistance in survivors compared with non-survivors. The vital message from this important work is that a multiply injured geriatric patient may appear “stable” yet have a profound perfusion deficit from a dangerously low cardiac output. The early use of invasive hemodynamic monitoring will identify this deficit and afford the opportunity to help improve survival.

The only randomized data concerning resuscitation in geriatric patients was conducted by Schultz et al.^[20]  These authors studied the role of physiologic monitoring in patients with fractures of the hip. Seventy patients were randomly divided into a monitored group and a control group. A central venous line was placed into the control group and a pulmonary artery catheter into the monitored group. The mean age for the nonmonitored group was 67 years (range, 40-89) and that for the monitored group was 78 years (range, 40-95). Based upon the data obtained, physiologic abnormalities were “appropriately corrected.” Postoperative morbidity was similar between the two groups. The postoperative mortality in the monitored group was 2.9% and the mortality in the nonmonitored group was 29%. The primary weakness n this study is that no clear parameters are provided tom guide resuscitation. This study evaluated patients with hip fractures and not the multisystem elderly trauma patient.

Tornetta et al. retrospectively reviewed 326 patients at four hospitals who were 60 years of age or greater.^[21]  Using univariate analysis, patients who died displayed significantly greater transfusion requirement (10.9 vs. 2.9 units) and fluid infusion (12.4 vs. 4.9 liters). Both transfusion and fluid requirements were found to be predictive of mortality. The authors concluded that the risks of invasive monitoring are justified in patients with ISS > 18, but for patients with ISS < 18, indications need to be clarified.

The importance of shock and fluid replacement in the elder trauma patient was addressed by Oreskovich et al.^[22]  One-hundred consecutive elderly patients (mean age 74 years) were followed for a minimum of one year. A profile of the non-survivor was constructed: 1. Pre-hospital intubation (93% mortality), 2. Shock (100%), 3. Intubated greater than 5 days (100%), and 4. Gram-negative pulmonary sepsis (80%). All non-survivors were in shock (systolic blood pressure < 80 mm Hg) for at least 15 minutes between injury and admission. Only 6% of survivors were found to be in shock. During this study the protocol for prehospital care in the hypotensive patient called for 2,200 ml. lactated Ringer’s solution prior to arrival at hospital.

Perdue et al. retrospectively studied 4,691 patients aged 16-64 years and compared these to 448 patients aged 65 years or greater.^[23]  Elderly mortality was 14% compared to 6% in the younger cohort and the difference was statistically significant (p < 0.001). After controlling for Injury Severity Score, Revised Trauma Score, pre-existing disease, and complications, the elderly were 4.6 times as likely to die compared to the young. The author’s practice is to admit elderly patients to ICU if they have significant injury (AIS > 3), shock, or significant chronic cardiovascular or renal disease. Pulmonary artery catheters were not placed unless volume or cardiac status is uncertain.

Knudson et al. retrospectively analyzed physiologic status in 852 blunt trauma patients aged 65 years or older.^[24] Mortality rose with a decreasing Trauma Score and mortality was 100% with a Trauma Score < 7. Each individual component of the TS was found to be predicative of mortality when analyzed independently. Systolic blood pressure < 90 mm Hg associated with 82% mortality rate. Multiple logistic regression used to construct formula to help predict which patients may benefit from aggressive resuscitation.

Physiologic status was also addressed by Pellicane et al.^[25] The authors reviewed 374 consecutive trauma patients over the age of 65 years. Trauma score was significantly (p < 0.001) higher in patients who survived. Mortality was significantly (p < 0.05) increased in patients with TS < 12 (65%) and TS = 12-14 (25%) when compared with patients with TS = 15-16 (5%). The authors concluded that geriatric patients with a TS < 15 are at high risk for complications and should be admitted to the ICU and treated aggressively.

Horst et al. retrospectively studied 39 trauma patients over the age of 60 years.^[26]  Patients were admitted to the intensive acre unit and monitored with arterial and pulmonary artery catheters. Fifteen (38%) of patients presented with shock (systolic blood pressure < 80 mm Hg). Although survivors tended to have higher mean arterial pressure, cardiac index, left ventricular stroke work, and oxygen delivery, the differences compared with non-survivors were not statistically significant.

The importance of shock was further underscored by Van Aalst et al.^[27]  The authors retrospectively analyzed 98 geriatric (? 65 years) blunt trauma patients with ISS ? 16. Of 48 surviving patients, only one patient presented in shock. This is compared with 50 patients who died where 15 presented in shock. The presence of shock (systolic blood pressure < 90 mm Hg) upon admission was the most significant factor associated with a poor outcome. Sepsis was also identified as a factor also contributing to poor outcome.

The state of resuscitation as evaluated by base deficit was evaluated by Davis et al.^[28]  The authors studied the utility of base deficit in 274 patients 55 years and older. Arterial blood gases obtained within one hour after admission. There was a statistically significant increase in mortality with increasing base deficit. Compared to a younger cohort, mortality in the elderly was significantly increased for a given base deficit despite similar Injury Severity Score. The positive predictive value of base deficit for significant injury was similar between young and old, but the negative predictive value was significantly better in younger patients. The authors concluded that a base deficit < ?6 is particularly ominous in elderly.

The above data indicate the use of necessary hemodynamic monitoring and careful trending of vital signs rather than relying on a single set of “normal” vitals.^[29]  Since the elderly patient is often not able to generate an augmented cardiac output in response to hemorrhage, early invasive hemodynamic monitoring and judicious use of vasoactive drugs (after appropriate fluid resuscitation) as recommended by Scalea should be recommended for any geriatric patient with significant injuries.

IV. Evidentiary Table

The articles listed in the evidentiary table are those utilized to formulate these guidelines for conduct of resuscitation and the use of invasive hemodynamic monitoring in resuscitation of the geriatric trauma patient. The data are listed in alphabetical order by first author of the publication. Included are: 1 Class I article, 1 Class II article and 7 Class III articles.

V. Summary

The elderly (65 years and older) are the fastest growing segment of the United States population. While trauma is only the seventh leading cause of death in the elderly, the incidence of injury (per 100,000) is significantly higher when compared to a younger cohort. United Sates Bureau of Census data indicate that in the future there will be an unprecedented number of elderly persons at risk for injury.

It is widely known that the elderly display a high incidence of premorbid conditions. However, the question of whether or not preexisting disease contributes to poor outcome after injury has yet to be conclusively answered. Several studies have indicated that shock, respiratory failure, decreasing trauma score, increasing injury severity score, increasing base deficit, and infectious complications portend a poor outcome in the elderly.

Data indicate that the multiply injured geriatric patient may appear “stable” yet have a profound perfusion deficit secondary to low cardiac output. The early use of invasive hemodynamic monitoring may afford the opportunity to help improve survival.

Although the injured elder is more likely to die than the younger patient, an aggressive treatment program will allow many geriatric patients to regain their preinjury independence. Attention to detail, while important for all trauma patients, must be heightened in the injured elder as the opportunity for good outcomes may be fleeting.

VI. Future Studies

The paucity of literature evaluating the conduct and end-points of resuscitation of the geriatric trauma patient requires that further clinical work be conducted. Randomized trials in severely injured geriatric patients must be done in order to determine which patients would benefit from invasive monitoring and the end-points which should be used for completing the resuscitation. Trials like this however have ethical, medicolegal, and methodological implications that may prevent their inception.

There are many parameters that have been shown to correlate with poor outcome in this population. We have no control over some of these, such as patient age. Some can be controlled with prevention techniques, as in the case of the pedestrian-motor vehicle crash, which has been shown to be associated with mortality. As clinical practitioners, we should focus our efforts on those areas where we would be able to exert an impact. The shock state, acidosis, and sepsis have been shown to directly correlate with mortality. Aggressive identification, correction, and monitoring of these pathophysiologic states may be able to improve outcome. Laboratory assays, such as base deficit, may have promise for measuring the adequacy and completeness of resuscitation. Certain drugs such as beta-blockers have been shown to improve outcome in elderly general surgery patients, but have not yet been studied in trauma patients.

References

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2. U.S. Bureau of the Census. Current Population Reports, Special Studies, P23-190, 65? in the United States. Available at:http://www.census.gov/prod/1/pop/p23-190/p23­190.html. Accessed 7/31/99.
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20. Schultz RJ, Whitfield GF, LaMura JJ, et al. The role of physiologic monitoring in patients with fractures of the hip. J Trauma 1985; 25:309-316.
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