Article, Geriatrics

Characteristics of elderly fall patients with baseline mental status: high-risk features for intracranial injury

a b s t r a c t

Background: Falls are a major cause of morbidity in the elderly.

Objectives: We describe the low-acuity elderly fall population and study which historical and clinical features predict traumatic intracranial injuries (ICIs).

Methods: This is a prospective observational study of patients at least 65 years old presenting with fall to a tertiary care facility. Patients were eligible if they were at baseline mental status and were not triaged to the trauma bay. At presentation, a data form was completed by treating physicians regarding mechanism and position of fall, history of head strike, headache, loss of consciousness (LOC), and signs of head trauma. radiographic imaging was obtained at the discretion of treating physicians. Medical records were subsequently reviewed to determine Imaging results. All patients were called in follow-up at 30 days to determine outcome in those not imaged. The study was institutional review board approved.

Results: A total of 799 patients were enrolled; 79.5% of patients underwent imaging. Twenty-seven had ICIs (3.4%). Fourteen had subdural hematoma, 7 had subarachnoid hemorrhage, 3 had cerebral contusion, and 3 had a combination of injuries. Logistic regression demonstrated 2 study variables that were associated with ICIs: LOC (odds ratio, 2.8; confidence interval, 1.2-6.3) and signs of head trauma (odds ratio, 13.2; confidence interval, 2.7-64.1). History of head strike, mechanism and position, headache, and anticoagulant and antiplatelet use were not associated with ICIs.

Conclusion: Elderly fall patients who are at their baseline mental status have a low incidence of ICIs. The best predictors of ICIs are physical findings of trauma to the head and history of LOC.

(C) 2014

Introduction

As many as one-third of people older than 65 years who live in the community fall each year, resulting in serious injury for at least 10% [1,2]. Head trauma is the most common cause of mortality in elderly patients who fall [3]. Computed tomographic (CT) imaging of the brain is a rapid and reliable tool that can be used to identify Intracranial injury (ICI); however, this technology is likely overused in patients with minor trauma [4]. In fact, the US Government Accountability Office found that the Medicare spending for advanced medical imaging more than doubled between 2000 and 2006 [5].

Several decision rules, such as the Canadian CT Head Rule, the New Orleans Criteria, National Emergency X-Radiography Utilization study-II (NEXUS-II) and the American College of Emergency Physicians (ACEP)

? Grants: None.

?? Presentations: Society of Academic Emergency Medicine, Atlanta, GA, May 2013.

* Corresponding author. St Luke’s Hospital and Health Network, Department of Emergency Medicine, 801 Ostrum St, Bethlehem, PA 18015, United States. Tel.: +1 610

838 6147.

E-mail address: [email protected] (R. Jeanmonod).

Clinical Policy Recommendations, have been developed and validated to assist with identifying patients at high risk for ICI after minor head trauma who would benefit from advanced imaging [6-9]. All of these guidelines suggest that a CT scan of the head should be performed in all patients older than 60 or 65 years suspected of minor head trauma; and therefore, they have little utility in differentiating elderly fall patients at increased risk for ICI [6-9].

There are several factors that might make elderly patients more likely to sustain an ICI after a minor trauma, such as use of anticoagulants and Antiplatelet agents, decreased agility and reflex time, and inability or failure to use a defensive posture. One of the more commonly cited reasons for increased injury in the elderly is the theoretical risk attributed to brain atrophy and the shearing of bridging veins in the setting of blunt trauma [10]. Some practitioners have construed this theoretical risk to include even those elderly fall patients who deny striking or hitting their heads. However, because of the increasing age of our population, the increasing utilization of CT imaging in emergency department (ED) care, and the imperative to decrease the cost of care, it would be a useful addition in the care of geriatric trauma patients to better define which historical and clinical factors are associated with ICI after fall.

http://dx.doi.org/10.1016/j.ajem.2014.04.051

0735-6757/(C) 2014

We sought to better describe the Geriatric population presenting to the ED with low-acuity falls (ie, not triaged to the trauma bay). We further sought to determine which historical and physical findings were most predictive of ICI in these patients who present at baseline mental status after a fall.

Materials and methods

Study design

This study is a prospective observational cohort of elderly fall patients. A convenience sample of patients was enrolled, and their medical records were subsequently reviewed. The research protocol was reviewed and approved by the institutional review board at the study facility. Patients or their family members or chronic care facility personnel provided verbal consent to participate in telephone contact follow-up at the time of enrollment.

Study setting and population

The study site is a level 1 community trauma center with an annual ED census of 75,000. The ED hosts an emergency medicine residency with 40 total residents. Resident and attending physicians were educated regarding the study with announcements made at least monthly during mandatory education time. Educational posters regard- ing the study were hung in high-frequency areas in the ED, and e-mail reminders were sent to all ED medical providers at least bimonthly.

Patients were eligible for enrollment in the study if they were 65 years or older and presented to the ED with a concern related to a fall. Additionally, patients were required to be at baseline neurologic status as per their family member or chronic care facility staff. Patients were excluded if they met major trauma criteria and were triaged to the trauma bay or if they were determined to have an acute change in baseline neurologic functioning as per the physician caring for the patient. Patients were not excluded because of dementia, aphasia, or any cognitive or neurologic deficit that was determined by the physician caring for the patient to be the patient’s baseline.

Study protocol and measurements

Patients eligible for this study were identified by attending and resident physicians working in the ED. When an eligible patient presented for care, the physician caring for the patient would assess whether the patient was at baseline neurologic function. Then he or she would ask for verbal consent from the patient, caretaker, or chronic care facility personnel for research associates to contact the patient, caretaker, or chronic care facility personnel by phone in follow-up. The physician caring for the patient then completed a data collection form regarding the patient’s mechanism and position at time of fall (obtained via history from the patient or witness), whether the fall was witnessed or not, time from event to ED evaluation in hours, history of head strike, presence of new headache, loss of consciousness (LOC), signs and location of head trauma, patient Place of residence, use of antiplatelet agents, and use of anticoagu- lants. The data collection form contained a closed list of possibilities for each question, and the provider caring for the patient was instructed to circle his or her responses. Data were entered by research associates into a standardized Microsoft Excel 2007 spreadsheet (Microsoft Corporation, Redmond, WA). Study patients were evaluated and dispositioned at the sole discretion of the treating physician team.

Research associates retrospectively reviewed each patient’s medical record after his or her ED visit to determine the results of any diagnostic testing, specifically radiographic imaging, the Disposition decision and service, and any neurosurgical interventions during the hospitalization. Other significant traumatic injuries were also recorded. Significant

traumatic injuries included visceral injuries or bony injuries. soft tissue injuries such as abrasions, contusions, skin tears, and lacerations were not recorded.

At 4 to 6 weeks after the initial ED visit, a research associate called study patients or their caregivers in follow-up. This was done to ensure that any patients who were neither admitted and observed nor imaged were in fact uninjured by the fall. Patients who were called were queried as to how they were feeling globally as well as specifically queried as to ongoing headache, dizziness, unsteadiness, neck pain, numbness, tingling, weakness, and the presence of other neurologic symptoms. Patients were queried about interval ED visits and their outcome. Patients with new or ongoing symptoms were encouraged to return to the ED for further evaluation. Date of follow- up and patient responses were recorded.

A patient was determined to have no significant acute head injury

(1) if he/she had a negative result on Head CT.performed, (2) if the patient was admitted to the hospital and had no sequelae at discharge,

(3) if review of his/her medical record revealed repeat Hospital visits unrelated to falls with no sequelae or concerns related to the index visit, or (4) if the patient had no concerns at 30 days postinjury in telephone follow-up.

Data analysis

With a predicted rate of ICI of 5% and given a desired statistical power of 0.8, a type I error rate of 0.05, and 9 independent predictors in our regression model, our projected sample size was 800. Independent predictors included position at time of injury, history of loss of consciousness, history of striking the head, concern of new headache, signs of head trauma on exam, aspirin use, other antiplatelet use, anticoagulant use, and presence of other significant traumatic injuries. Multiple logistic regression was done using these variables to determine which variables best predicted the outcome of ICI. Data were also analyzed using descriptive statistics and ?2. Data were analyzed using MedCalc (1993-2013, Ostend, Belgium) and Microsoft Excel 2007 (Microsoft Corporation).

Results

Demographic data

Eight hundred patients with fall events were enrolled over 16 months in 2011-2012. One patient fall event was excluded because the patient was enrolled in the study twice during a single visit by 2 different providers, leaving 799 for analysis. The demographics of the enrolled patients are shown in Table 1.

Most falls were unwitnessed (62.3%), and this did not differ between patients presenting from home and those presenting from nursing homes and assisted living facilities (P = .37). Six hundred thirteen (76.7%) of the 799 patients presented within 6 hours of the fall; 19.1% presented more than 6 hours after the fall; and, in 4.2% of cases, the time of fall could not be determined. Patients coming from home were more likely to present in a delayed fashion as compared to those coming from nursing homes or assisted living facilities (odds ratio [OR], 3.2; confidence interval [CI], 2.1-4.9; P b .0001), and they were more likely to be admitted to the hospital (48.7% from home were admitted compared to 36% of patients coming from nursing homes; OR, 1.7; CI, 1.3-2.2; P = .0004). A total of 46.8% of patients were admitted for medical conditions, 44.5% were admitted for surgical conditions, and 8.7% were admitted for both.

Most patients were taking antiplatelet or anticoagulant medica- tions, the details of which are listed in Table 2. In 5 patients, complete Medication lists were not available.

Two hundred seven (25.9% of the total cohort) patients reported that they did not hit their heads. A total of 52.7% of these patients did not undergo head CT evaluation at the discretion of the treating

Table 1

799 Patients

Head CT

n = 632

No Head CT

n = 167

Admitted

n = 60

Discharged

n = 107

Follow-up Phone Interview

n = 102

Repeat Hospital Visit

n = 1

Lost to Follow-Up n = 4

Baseline characteristics

Total (N = 799)

Median age (IQR) 85 (79-90)

Sex (%)

Male 265 (33.2)

Female 534 (66.8)

Living environment (%)

Home 450 (56.3)

Assisted living and nursing home 327 (40.9)

Other 20 (2.5)

Time to presentation (%)

0-2 h 490 (61.3)

2-6 h 126 (15.8)

6-24 h 69 (8.6)

N 24 h 85 (10.6)

Unknown 30 (3.8)

Mechanism of fall (%)

Trip

249 (31.2)

Loss of balance

219 (27.4)

Weakness

39 (4.9)

Dizziness

30 (3.8)

Syncope

40 (5.0)

Unsure

222 (27.8)

Position prior to fall (%) Standing

536 (67.1)

Seated

116 (14.5)

Lying

49 (6.1)

Climbing stairs

10 (1.3)

Unknown

88 (11.0)

Characteristics of enrolled patients. Fig. Variables associated with intracranial injury.

provider. This differed significantly from the 475 patients who had a reported head strike, of whom only 9.5% were not imaged. There was one subdural hematoma found in a patient with no reported head strike, representing an incidence of 0.5% in the population without reported head trauma. Overall, 79.1% of patients underwent head CT (Figure).

A total of 24.9% of patients had traumatic orthopedic injuries. There were no differences in injury rates between patients from home and patients from facilities. Twenty-six (3.3%) patients had traumatic ICI at evaluation, and 1 patient who was not imaged at initial evaluation had a CT head done shortly after admission demonstrating an acute SDH, resulting in 27 total ICIs (3.4%). The most common injury was SDH (n = 14), followed by subarachnoid hemorrhage (n = 7), cerebral contusion (n = 3), and combination injuries (n = 3). Two patients with SDH underwent neurosurgical intervention for their injuries during the course of their hospitalizations, and 1 patient died in the ED.

Excluding the 4 patients lost to follow-up, only loss of consciousness and signs of trauma to the head/face were associated with ICI (Table 3). Position at time of fall, history of head strike, loss of consciousness, presence of new headache, aspirin use, anticoagulant use, other antiplatelet agent use, and presence of other significant traumatic injuries were not associated with ICI (Table 3). The sensitivity and

specificity for signs of trauma to the face/head or loss of consciousness were 92.6% (74.2-98.7) and 40.2% (36.8-43.8), respectively. The positive predictive value in this “low-acuity” cohort was 5.2% (3.4-7.6), and the negative predictive value was 99.4% (97.4-99.9).

Discussion

Unlike similar studies in heterogeneous patient populations, our study population included only elderly patients 65 years or older. Most studies looking at Minor head injury automatically exclude patients with a glasgow coma scale (GCS) less than 15 because this could herald a significant brain injury. However, cognitive impair- ment at baseline is a notable and common attribute among the elderly population. Among nursing home patients, it is estimated that only about one-third have no cognitive impairment but that more than half have moderate to severe impairment [11]. The prevalence of cognitive impairment in noninstitutionalized elders has not been well studied, but voluntary surveys indicate that 12.7% of elders report memory impairment and confusion and more than one-third of those additionally report a related functional decline [12]. A recent prospective study concluded that 26% of elderly patients presenting to the ED exhibited evidence of cognitive impairment [13]. For these reasons, we elected to include patients who were at baseline mental

Table 2

Antiplatelet and anticoagulant use in elderly fall patients

Total

No ICI

ICI

Table 3

Multivariate logistic regression with adjusted odds ratios

Variable OR (95% CI)

Position (standing or climbing) 1.97 (0.57-6.85)

History of hitting head 0.51 (0.07-3.73)

(n = 799)

(n = 773)

(n = 26)

Loss of consciousness

2.77 (1.23-6.27)?

No antiplatelet or anticoagulant (%)

298 (37.3)

290 (37.5)

8 (30.8)

New headache

1.84 (0.77-4.42)

Aspirin (%)

345 (43.2)

330 (42.7)

15 (57.7)

Aspirin

1.77 (0.79-3.97)

Coumadin (%)

140 (17.5)

137 (17.7)

3 (11.5)

Coumadin

0.82 (0.23-2.90)

Plavix and other antiplatelets

or anticoagulants (%)

104 (13.0)

101 (13.1)

3 (11.5)

Plavix, other antiplatelet/anticoagulant

Signs of head trauma

0.69 (0.19-2.44)

13.2 (2.7-64.1)?

Multiple agents (%)

86 (10.8)

83 (10.7)

3 (11.5)

Other visceral or bony injuries (excluding Facial fractures)

1.88 (0.68-5.25)

Antiplatelet and anticoagulant use in elderly fall patients. ? Statistically significant variables.

status per sending facility or family irrespective of GCS to better represent the patient population in question.

In addition to cognitive impairment, other differences distinguish elderly fall patients living in the community from institutionalized patients. We have shown for the first time that elderly fall patients living in the community are less likely to seek care in a timely fashion compared to nursing home patients. This can likely be attributed to a number of factors including the nature of the injury, poor social and physical function, lack of transportation, fear of losing independence, and lack of insurance or financial security. We also found that elders coming from the community were more likely to be admitted to the hospital despite the fact that they were not more likely to have significant traumatic injuries. This increased admission rate among patients coming from the community may be due in part to questions regarding the mechanism of fall, lack of reliable follow-up, transpor- tation, socioeconomic considerations, and living alone. Studies have demonstrated a high rate of admission of elderly fall patients [13,14]. Elders who fall have a high incidence of functional decline and often require additional support for months after falling [15]. As a result, many of these patients are eventually discharged from the hospital to long-term care facilities [12-14,16]. Although falls in elderly patients may be a sign of an acute illness, recurrent falls can also predict declining function and cognitive impairment [17].

Falls are the leading cause of fatal and nonfatal injuries among older adults [15]. In this study, 1 in 4 patients experienced a traumatic injury from their fall. More than 1 in 5 suffered an orthopedic injury such as a dislocation or fracture. This is comparable to injury patterns identified previously in the literature [18]. This further highlights the vulnerability of this patient population and, considering the high rate of recurrent falling, the need for further evaluation prior to discharge. Tiedemann et al [19] demonstrated a simple 2-item screening tool that could be used to identify elders at high risk for falls in the ED. However, once identified, it is unclear what interventions are necessary to reduce the risk of subsequent falls. A study exploring Preventive strategies in elderly fall patients with cognitive dysfunc- tion failed to demonstrate reduction in fall recidivism in their intervention cohort [20].

Of the 799 patients included in this study, 27 (3.4%) ICIs were identified by CT. The incidence of ICI was somewhat lower in our study population compared to other studies involving elders with head trauma [7,21,22]; however, our study did not include patients triaged to the trauma bay. Although the Centers for Disease Control and Prevention report that falls are the leading cause of traumatic brain injury in elderly patients and a leading cause of mortality, these data are likely not representative of the lower-risk cohort of elderly patients who present at their baseline mental status after a fall from standing. A retrospective Italian study of more than 2000 elderly patients with minor head trauma demonstrated a rate of ICI of only 2.2%, with fewer than 0.2% of patients requiring neurosurgical intervention [23]. That study specifically excluded patients with GCS less than 15 and those on anticoagulant therapy but does suggest that there is a subset of elderly fall patients who may not need to undergo CT scanning as part of their fall evaluation [23].

Using logistic regression, we found that the best predictors of ICI are physical findings of trauma to the head and history of a loss of consciousness. These 2 items together had a sensitivity of 92.6% and a specificity of 40.2% in detecting ICI in this cohort. Our small number of ICI precludes construction of a decision rule from these data but does suggest that perhaps not all elder fallers require head CT. Even in the case of ICI, neurosurgical intervention is often unnecessary [24-26]. Instead, asymptomatic patients are typically observed for evidence of deterioration. Before the advent of CT, this was the standard of care for all patients with suspected ICI. Although there is significant pressure to identify all injuries in the ED, it may be prudent to consider whether this practice is the best use of our resources and whether an alternative strategy might be employed. As mentioned, the likelihood

of cognitive impairment and need for further evaluation is often necessary in elder fallers regardless of head injury status. A geriatric observation unit might be one possible solution that would serve to give hospital staff the appropriate venue to further assess elderly fall patients and also serve to reduce the use of CT scans by observing patients for signs of Neurological deterioration in those who are otherwise low risk [27].

The risk of ICI in those taking anticoagulants and antiplatelet agents remains disputed. The current literature regarding the risk of these agents is mixed, with some studies suggesting increased risk of ICI [23,28-31], whereas others suggest that there is no increased risk [32-35]. These studies seem to be limited by their small sample sizes, retrospective nature, or inclusion of patients from a trauma registry, who likely represent a higher-risk population with incorporated selection bias. Sixty-two percent of elders in our study cohort were on an antiplatelet or anticoagulant medication, but this did not correspond to an increased risk of traumatic ICH in these elders with normal mental status after a fall event.

This study has several limitations. As stated above, not all patients were imaged; and although they were assumed to represent negative evaluations given the fact that they were asymptomatic at follow-up, they could have had small intracranial bleeds that were not clinically obvious. The importance of these hypothetical misses is questionable given the lack of neurosurgical intervention. Similarly, there was variability in providers’ evaluation of patients without head strike, where patients without head strike were less likely to have a CT of the head performed. Given that at least 1 patient with no reported head strike had an SDH on CT, there could have been other missed injuries, leading to an underestimation of disease prevalence. Additionally, the lower-than-predicted incidence of ICI in our study population could have resulted in overfitting of the variables.

These data were collected from a subset of elder patients triaged to an ED and excluded patients triaged to the trauma bay. Therefore, the findings and associations may not be applicable to those with more significant mechanisms such as falls down a flight of stairs. Likewise, because we only studied patients who were at their baseline mental status, the findings of this study should not be applied to those with altered mental status.

This is a convenience sample of patients and is subject to enrollment bias. We were unable to retrospectively determine the total number of fall patients who presented to the ED during enrollment to assess for differences in the population enrolled as compared to the population who was not enrolled. This was not feasible because of the tremendous number of chief concerns that might represent “fall” (such as “hip pain,” “head injury,” “syncope,” “weakness”) and the search limitations of the electronic medical record. Although every attempt was made to enroll all eligible patients, we cannot determine if the enrolled population was completely representative of all ED fall patients.

Finally, the patients were enrolled at a single community-based academic institution and may not be representative of the elderly population at large.

Conclusions

The incidence of CT-identified ICI in elder patients who are at their baseline mental status presenting to the ED after a fall is low. Signs of trauma to the head and face or loss of consciousness is predictive of ICI. Larger studies are needed to determine if elderly patients may forgo head CT after a low-risk fall event.

Conflict of interest statement

No authors have conflicts of interest to report.

Author contribution

Study conception: DA, DJ, RJ Study design: DA, DJ, RJ

Data collection and handling: DA, RJ, KH Data analysis: DJ, RJ

Data interpretation: DJ, RJ, KH, MR Drafting of manuscript: DJ, RJ, KH, MR, DW

Editing and revision of manuscript: DJ, RJ, DA, KH, MR, DW Responsible for manuscript as a whole: RJ, DJ

References

  1. Tinetti ME, Williams CS. Falls, injuries due to falls, and the risk of admission to a nursing home. N Engl J Med 1997;337:1279-84.
  2. Stevens JA, Corso PS, Finkelstein EA, Miller TR. The costs of fatal and non-fatal falls among older adults. Inj Prev 2006;12:290-5.
  3. Gerber LM, Ni Q, Hartl R, Ghajar J. Impact of falls on early mortality from severe traumatic brain injury. J Trauma Manag Outcomes 2009;3:9.
  4. Melnick ER, Szlezak CM, Bentley SK, Dziura JD, Kotlyar S, Post LA. CT overuse for mild traumatic brain injury. Jt Comm J Qual Patient Saf 2012;38:483-9.
  5. Government Accountability Office (GAO). Medicare part B imaging services: rapid spending growth and shift to physician offices indicate need for CMS to consider additional management practices. Washington DC: U.S. Government Account- ability Office; 2008.
  6. Stiell IG, Wells GA, Vandemheen K, Clement C, Lesiuk H, Laupacis A, et al. The Canadian CT head rule for patients with minor head injury. Lancet 2001;357:1391-6.
  7. Haydel MJ, Preston CA, Mills TJ, Luber S, Blaudeau E, DeBlieux PM. Indications for computed tomoagraphy in patients with minor head injury. N Engl J Med 2000;343:100-5.
  8. Jagoda AS, Bazarian JJ, Bruns JJ, Cantrill SV, Gean AD, Howard PK, et al. Clinical policy: neuroimaging and decisionmaking in adult mild traumatic brain injury in the acute setting. Ann Emerg Med 2008;52:714-48.
  9. Mower WR, Hoffman JR, Herbert M, Wolfson AB, Pollack Jr CV, Zucker MI. Developing a decision instrument to guide computed tomographic imaging of blunt head injury patients. J Trauma 2005;59:954-9.
  10. Birnbaumer DM. Geriatric trauma. In: Marx JA, Lockberger RS, Walls RM, Adams JG, editors. Rosen’s emergency medicine: concepts and clinical practice7th ed.; 2010. p. 286-94.
  11. Nursing Home Compendium. [Internet] http://www.cms.gov/Medicare/Provider- Enrollment-and-Certification/CertificationandComplianc/downloads/nursingho- medatacompendium_508.pdf; 2012. [Accessed 10/31/13].
  12. Centers for Disease Control and Prevention (CDC). Self-reported increased confusion or Memory loss and associated functional difficulties among adults aged >=60 years — 21 states, 2011. MMWR Morb Mortal Wkly Rep 2013;62:347-50.
  13. Gray LC, Peel NM, Costa AP, Burkett E, Dey AB, Jonsson PV, et al. Profiles of older patients in the emergency department: findings from the interRAI Multinational Emergency Department Study. Ann Emerg Med 2013;62:467-74.
  14. Paniagua MA, Malphurs JE, Phelan EA. Older patients presenting to a county hospital ED after a fall: missed opportunities for prevention. Am J Emerg Med 2006;24:413-7.
  15. Schiller JS, Kramarow EA, Dey AN. Fall injury episodes among noninstitutionalized older adults: United States, 2001-2003. Advance data from vital and health statistics; no 392. Hyattsville, MD: National Center for Health Statistics; 2007.
  16. Scott JC. Osteoporosis and Hip fractures. Rheum Dis Clin North Am 1990;16:717-40.
  17. Fuller GF. Falls in the elderly. Am Fam Physician 2000;61(2159-68):2173-4.
  18. Sterling DA, O’Connor JA, Bonadies J. Geriatric falls: injury severity is high and disproportionate to mechanism. J Trauma 2001;50:116-9.
  19. Tiedemann A, Sherrington C, Orr T, Hallen J, Lewis D, Kelly A, et al. Identifying older people at high risk of future falls: development and validation of a screening tool for use in emergency departments. Emerg Med J 2012;30(11):918-22.
  20. Shaw FE, Bond J, Richardson DA, Dawson P, Steen IN, McKeith IG, et al. Multifactorial intervention after a fall in older people with cognitive impairment and dementia presenting to the accident and emergency department: randomised controlled trial. BMJ 2003;326:73-8.
  21. Mack LR, Chan SB, Silva JC, Hogan TM. The use of head computed tomography in elderly patients sustaining minor head trauma. J Emerg Med 2003;24:157-62.
  22. Rathlev NK, Medzon R, Lowery D, Pollack C, Bracken M, Barest G, et al. Intracranial pathology in elders with Blunt head trauma. Acad Emerg Med 2006;13:302-7.
  23. Riccardi A, Frumento F, Guiddo G, Spinola MB, Corti L, Minuto P, et al. Minor head injury in the elderly at Very low risk: a retrospective study of 6 years in an emergency department. Am J Emerg Med 2013;31:37-41.
  24. Ibanez J, Arikan F, Pedraza S, Sanchez E, 26.Papa L, Stiell IG, Clement CM, Pawlowicz A, Wolfram A, Braga C, et al. Performance of the Canadian CT Head Rule and the New Orleans Criteria for predicting any traumatic intracranial injury on computed tomography in a United States Level I Trauma Center. Acad Emerg Med 2012;19:2-10.
  25. Borczuk P, Penn J, Peak D, Chang Y. Patients with traumatic subarachnoid hemorrhage are at low risk for deterioration or neurosurgical intervention. J Trauma Acute Care Surg 2013;74:1504-9.
  26. Nagurney JT, Borczuk P, Thomas SH. Elderly patients with closed head trauma after a fall: mechanisms and outcomes. J Emerg Med 1998;16:709-13.
  27. Foo CL, Siu VW, Tan TL, Ding YY, Seow E. geriatric assessment and intervention in an emergency department observation unit reduced re-attendance and hospita- lisation rates. Australas J Ageing 2012;31:40-6.
  28. Claudia C, Claudia R, Agostino O, Simone M, Stefano G. Minor head injury in warfarinized patients: indicators of risk for intracranial hemorrhage. J Trauma 2011;70:906-9.
  29. Pieracci FM, Eachempati SR, Shou J, Hydo LJ, Barie PS. Use of long-term anticoagulation is associated with traumatic intracranial hemorrhage and subsequent mortality in elderly patients hospitalized after falls: analysis of the New York State Administrative Database. J Trauma 2007;63:519-24.
  30. Franko J, Kish KJ, O’Connell BG, Subramanian S, Yuschak JV. Advanced age and preinjury warfarin anticoagulation increase the risk of mortality after head trauma. J Trauma 2006;61:107-10.
  31. Karni A, Holtzman R, Bass T, Zorman G, Carter L, Rodriguez L, et al. Traumatic head injury in the anticoagulated elderly patient: a lethal combination. Am Surg 2001;67:1098-100.
  32. Pieracci FM, Eachempati SR, Shou J, Hydo LJ, Barie PS. Degree of anticoagulation, but not warfarin use itself, predicts adverse outcomes after traumatic brain injury in elderly trauma patients. J Trauma 2007;63:525-30.
  33. Gage BF, Birman-Deych E, Kerzner R, Radford MJ, Nilasena DS, Rich MW. Incidence of intracranial hemorrhage in patients with atrial fibrillation who are prone to fall. Am J Med 2005;118:612-7.
  34. Kennedy DM, Cipolle MD, Pasquale MD, Wasser T. Impact of preinjury warfarin use in elderly trauma patients. J Trauma 2000;48:451-3.
  35. Garra G, Nashed AH, Capobianco L. Minor head trauma in Anticoagulated patients. Acad Emerg Med 1999;6:121-4.