CDEM-17July-web

Volume 31 Number 7 July 2017

Nature’s Course

The physiological consequences of aging combined with
the environmental and exertional stressors of outdoor
settings put geriatric patients at particularly high risk
for wilderness-related emergencies. When managing
such cases, the emergency physician must be able to
prioritize treatments, both on scene and in the hospital;
pinpoint underlying problems that can contribute to, or
exacerbate, trauma in the elderly; and be prepared to
manage a variety of common illnesses and injuries that
occur in various environments.

Sobering Symptoms

Alcohol dependence extends across all socioeconomic
classes, affecting an estimated 8.5% of adults in the
United States. While excess drinking is notoriously – and
quite obviously – problematic, the cessation of alcohol
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THE OFFICIAL CME PUBLICATION OF THE AMERICAN COLLEGE OF EMERGENCY PHYSICIANS

IN THIS ISSUE Critical Decisions in Emergency Medicine is the official
CME publication of the American College of Emergency
Lesson 13 n Elderly vs the Elements . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 Physicians. Additional volumes are available to keep
emergency medicine professionals up to date on
LLSA Literature Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 relevant clinical issues.

Critical Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12 EDITOR-IN-CHIEF

Critical ECG . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 Michael S. Beeson, MD, MBA, FACEP
Northeastern Ohio Universities,
Lesson 14 n Alcohol Withdrawal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Rootstown, OH

Critical Image . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 SECTION EDITORS
Andrew J. Eyre, MD
CME Questions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22 Brigham & Women’s Hospital/Harvard Medical School,

Drug Box/Tox Box . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 Boston, MA

Contributor Disclosures. In accordance with the ACCME Standards for Commercial Joshua S. Broder, MD, FACEP
Support and policy of the American College of Emergency Physicians, all individuals with Duke University, Durham, NC
control over CME content (including but not limited to staff, planners, reviewers, and
authors) must disclose whether or not they have any relevant financial relationship(s) to Frank LoVecchio, DO, MPH, FACEP
learners prior to the start of the activity. These individuals have indicated that they have Maricopa Medical Center/Banner Phoenix Poison
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perceived by some as a real or apparent conflict of interest (eg, ownership of stock, grants, and Drug Information Center, Phoenix, AZ
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CME activity. Sharon E. Mace, MD, FACEP; Baxter Healthcare, consulting fees, fees for non- Amal Mattu, MD, FACEP
CME services, and contracted research; Gebauer Company, contracted research; Halozyme, University of Maryland, Baltimore, MD
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CME content have no significant financial interests or relationships to disclose. University of Texas Southwestern Medical Center,

Method of Participation. This educational activity consists of two lessons, a post-test, Dallas, TX
and evaluation questions; as designed, the activity it should take approximately 5 hours to
complete. The participant should, in order, review the learning objectives, read the lessons Christian A. Tomaszewski, MD, MS, MBA, FACEP
as published in the print or online version, and complete the online post-test (a minimum University of California Health Sciences,
score of 75% is required) and evaluation questions. Release date July 1, 2017. Expiration San Diego, CA
June 31, 2020.
Steven J. Warrington, MD, MEd
Accreditation Statement. The American College of Emergency Physicians is accredited by Kaweah Delta Medical Center, Visalia, CA
the Accreditation Council for Continuing Medical Education to provide continuing medical
education for physicians. ASSOCIATE EDITORS
Walter L. Green, MD, FACEP
The American College of Emergency Physicians designates this enduring material for a University of Texas Southwestern Medical Center,
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Nature’s Course

The Elderly vs
the Elements

LESSON 13

By Kris R. Lehnhardt, MD, FACEP; and Leah E. Jacoby, MD
Not pictured: Ty B. Nichols, MD; Rachael Slivka, MD; and
Aaron Surrey

Drs. Lehnhardt and Jacoby are assistant professors, Dr. Nichols is senior resident,
and Dr. Slivka is assistant clinical professor in the Department of Emergency
Medicine at George Washington University in Washington, DC. Mr. Surrey is a
senior medical student in the School of Medicine and Health Sciences at George
Washington University.

Reviewed by Nathaniel Mann, MD

OBJECTIVES CRITICAL DECISIONS

On completion of this lesson, you should be able to: n What environmental factors put the elderly at
increased risk for wilderness-related injury or
1. Identify wilderness-related illnesses and injuries commonly illness?
seen in elderly patients.
n What common complications must be
2. Detail the treatment priorities for elderly patients, both in considered when evaluating an elderly patient
the wilderness and after transport to the hospital. presenting from a wilderness setting?

3. Describe how the natural aging process can negatively n What priorities must be kept in mind when
affect older patients participating in outdoor activities. managing a geriatric patient in an outdoor
environment?
4. Analyze how underlying problems can contribute to,
or exacerbate, the medical/traumatic presentation of n What special factors should be considered
patients presenting from a wilderness setting. during the in-hospital evaluation of an elderly
patient presenting from a wilderness setting?
5. Explain how certain environmental stressors can escalate
the risk of illness or injury in the geriatric population.

FROM THE EM MODEL

6.0 Environmental Disorders
18.0 Traumatic Disorders

It’s no secret that the population of the United States is aging. Dramatic advancements in medical care and the
maturation of the baby boomer generation have triggered a “silver tsunami” that has major ramifications for medicine.
By 2030, nearly 21% of Americans will be 65 years or older (a sharp increase from 13.7% in 2014).1 Many of these
patients will remain active well into their twilight years — a dynamic that is creating new challenges for emergency
physicians, who must manage the increasing number of seniors with acute recreation-related illnesses and injuries.

July 2017 n Volume 31 Number 7 3

CASE PRESENTATIONS administered, after which the patient report that he was shivering and
became more obtunded. oriented to person only. The patient,
■ CASE ONE who showed signs of head trauma and
Upon arrival, her vital signs are an open ankle fracture, was placed
The hospital is notified that blood pressure 187/85, heart rate in a cervical collar and his ankle was
emergency medical services (EMS) 110, temperature 39°C (102.2°F), splinted. He was secured in a litter
is evacuating a 69-year-old woman and oxygen saturation 85%; her and bundled with dry blankets before
from Grand Canyon National Park; Glasgow Coma Scale (GCS) score is being transported to a location that
she is in critical condition. The 8. The emergency physician intubates was accessible to a rescue vehicle.
elderly patient was participating in the patient for airway protection,
a week-long professionally guided places a second intravenous (IV) line, Upon arrival, he is speaking but
rafting trip down the Colorado administers an additional liter of confused. His initial vital signs are
River, but became confused on day normal saline, and draws blood for a blood pressure 210/100, heart rate
3. She is an inexperienced rafter with complete blood count, chemistry panel, 96, temperature 36°C (97°F), and
a medical history only significant and creatine kinase measurement. An oxygen saturation 98% on room air.
for hypertension controlled with electrocardiogram (ECG) is ordered and EMS reports that the patient takes
hydrochlorothiazide. On the second a Foley catheter is placed to measure warfarin for atrial fibrillation. The
day of the trip, she reported nausea urine output. trauma survey reveals a large posterior
and could not remember the last time scalp hematoma, a hemostatic open
she had urinated, although she insisted ■ CASE TWO ankle fracture, and a non-tender
she had been drinking plenty of water. cervical spine. Two large-bore IVs are
The hospital is notified that EMS placed, blood is drawn, and warm
When EMS arrived, the patient’s will be arriving shortly with a 78-year- intravenous fluids, antibiotics, and a
wetsuit was covered in emesis and she old man who had been missing for 2 tetanus booster for his ankle fracture
was postictal, having just experienced days. He was located at the bottom are initiated.
a generalized tonic-clonic seizure. of a ravine by search and rescue, who
Five milligrams of midazolam plus
1,000 mL of normal saline was

The physiological and pathological individuals; some simply get “old” CRITICAL DECISION
consequences of aging combined with faster than others. This disparity is
the environmental and exertional due to a multitude of factors, including What environmental factors
stressors of wilderness activities put lifestyle, environment, and genetics. put the elderly at increased risk
this population at particularly high As such, each patient ultimately must for wilderness-related injury or
risk of medical complications while be evaluated on an individual basis to illness?
outdoors. Furthermore, chronic identify the particular risk factors that
conditions can compound any injuries increase the likelihood of medical illness When treating a geriatric patient in
that do occur.2 These perils are further or injury. any setting, comorbidities must be taken
potentiated by an increased accessibility into account; approximately 80% of
to remote locations due to improved Patients between 65 and 74 years Americans over the age of 65 suffer from
infrastructure and transportation; old conventionally have been termed at least one chronic condition.5 Many of
consequently, definitive care often is a early elderly, and those older than 75 these disorders can predispose patients
substantial distance away. years are categorized as late elderly.3 to injury and escalate the risks associated
However, a more precise definition with outdoor recreation. That said, older
Defining “Elderly” involves three separate barometers of adults may be able to minimize this
age: chronology (a patient’s number risk by undergoing a pre-participation
Aging, a natural process that of life years), pathology (individual evaluation prior to embarking on any
leads to anatomical and physiological changes associated with disease states, wilderness activity.6,7
alterations in each and every organ and functionality (an individual’s ability
system, can be described as the human to function as a result of pathological Heat
life exceeding its reserve capacity and physiological changes).4 In this
(Table 1). However, the term elderly review, we identify patients based Underlying medical problems and
can be difficult to define; experts use on chronological age and discuss the the drugs prescribed to treat them
myriad age cutoffs when describing the pathological risks and functionality may increase the risk for heat-related
geriatric population. While all human therein. illness.8 This is especially true among
beings age chronologically at the same older adults, who often suffer from
rate, physiological and anatomical diminished functional reserves.
vitality varies widely between Of greatest concern are diagnoses

4 Critical Decisions in Emergency Medicine

and medications that may induce ability to resist continued decreases in sympathetic tone, pulmonary
dehydration or otherwise impair a in temperature when in contact with artery vasoconstriction, and blood
patient’s ability to dissipate heat. cold surfaces. Conversely, unoccluded pressure.6 These changes can create
Cardiac dysfunction and vascular vessels appear to be capable of significant stress in those with severe
disease are particularly notable, as maintaining a minimum average pulmonary vascular disorders. In the
they may impede the body’s ability temperature.13 This finding may point wilderness participant with coronary
to redistribute blood to the skin for to an elevated frostbite risk in geriatric artery disease, these effects can reduce
cooling. patients, greater injury severity, and the threshold for cardiac ischemia,
increased difficulty rewarming cold especially with exertion; however,
Diuretic medications increase the extremities. exercise tolerance appears to normalize
risk of volume depletion, especially in after several days at altitude.21 The
patients unaccustomed to the higher Peripheral neuropathy, most increased sympathetic tone also
levels of heat and exertion often commonly caused by diabetes, also may increase the risk of arrhythmia
involved in wilderness and outdoor increases the risk of cold-related injury and heart failure among those with
activities. Beta-blockers can hinder to the extremities, much in the same underlying cardiac dysfunction.6
cooling by reducing cardiac output and way it elevates the risk of skin ulcers or
preventing peripheral vasodilation. other extremity trauma.14 Importantly, CRITICAL DECISION
Medications with anticholinergic effects the elderly are at greater risk for
(eg, antidepressants, antihistamines, hypothermia due to their generally What common complications
and antispasmodics) may diminish the diminished ability to produce and retain must be considered when
production of sweat and compromise heat. This process likely is related to evaluating an elderly patient
thermal regulation. the loss of muscle mass over time and presenting from a wilderness
higher prevalence of baseline diseases in setting?
Antipsychotic and antiepileptic the older population.15,16
medications also can impair While older populations are prone
thermoregulation, although the Altitude to the same kinds of illnesses and
mechanisms are less clear. Interestingly, injuries in the outdoors as they would
heat exposure has also been noted Healthy older adults are at no greater be elsewhere, additional exertion and
to cause hyperglycemia in those risk for high-altitude illnesses than their the perils associated with wilderness
with diabetes mellitus; however, the younger counterparts; in fact, age may activities increase the danger.
immediate clinical effects of this are be protective against the development
uncertain.7 of altitude sickness.6,7,17 Elderly patients Cardiac
with asymptomatic baseline diseases
Cold such as CAD, diabetes, or chronic Heart disease remains the leading
obstructive pulmonary disease (COPD) cause of death in patients 65 years and
Many wilderness activities such can safely tolerate rises in elevation to at older.22 Aging decreases cardiac output
as skiing and mountaineering take least 2,500 meters (although this does and maximal heart rate and elevates
place in cold environments, which not necessarily include exertion at those blood pressure and the incidence
can exacerbate several chronic disease altitudes).18 of coronary artery disease, each
states. Cold is widely noted to have contributing to a greater incidence of
deleterious effects in patients with That said, underlying medical cardiac events.23 Forty percent of all
coronary artery disease (CAD) because conditions should be considered fatalities caused by downhill skiing
of its tendency to cause vasoconstriction potential risk factors in high-altitude are due to sudden cardiac death, 90%
and, consequently, increased cardiac environments. Baseline lung disorders of which occur in men over the age of
work. This effect, which is seen both (eg, COPD or interstitial lung disease) 34 years.24 The primary risk factors in
at rest and during exercise, may cause can lead to diminished oxygenation such cases include a prior myocardial
angina at levels of exertion that patients at altitude, as the partial pressure of infarction (MI), hypertension, known
could otherwise achieve without oxygen in the ambient air declines with CAD without a prior MI, and a lack
symptoms.9,10 Similarly, several studies a rise in elevation. Although the rate of of engagement in regular vigorous
have demonstrated an association clinically significant effects is unclear, activities.
between deaths related to CAD and patients with severe or symptomatic
lower environmental temperatures.11,12 pulmonary disease should be In activities such as mountain
cautioned against altitude exposure or trekking, reduced oxygen availability
As exposure to cold increases exertion beyond baseline levels. These in the setting of increased sympathetic
systemic vascular resistance through comorbidities are likely to hinder a activation, thermal stressors,
vasoconstriction, there is a theoretical patient’s ability to acclimate adequately, dehydration, and emotional stress put
risk of congestive heart failure and and may contribute to the development great demands on the heart. The strain
subsequent acute pulmonary edema. of altitude disease.6,7,19,20 can exacerbate or even cause new
Experiments creating mechanical symptoms in patients with subclinical
obstruction to arterial flow have shown Normal physiological responses atherosclerosis.25
a significant impairment in the fingers’ to high altitudes include an increase

July 2017 n Volume 31 Number 7 5

TABLE 1. Age-Related Anatomical and Physiological Changes and Their Functional Consequences

Organ System Anatomical Changes Physiological Changes Functional Consequences
General Decreased organ and muscle Decreased organ function; Decreased flexibility, endurance,
Cardiovascular mass decreased oxygen consumption and maximal performance
Fibrosis and thickening of Decreased maximal heart rate each Decreased cardiac output;
Lungs arteries; sclerosis of cardiac decade of life; decreased beta- decreased physical work capacity;
Kidneys valves; elongation and tortuosity adrenergic responses; decreased orthostatic hypotension; decreased
Genitourinary of aorta arterial compliance endurance; syncope; shortness of
Gastrointestinal breath
Hematological and Decreased lung elasticity; Decreased vital capacity; Shortness of breath; cough;
Immunological decreased activity of cilia; microaspiration aspiration pneumonia
Musculoskeletal reduced cough reflex
Increased number of abnormal Decreased glomerular filtration Delayed response to salt or fluid
Endocrine glomeruli rate; decreased renal blood flow; restriction; nocturia
decreased urine concentration;
Nervous Prostatic enlargement; vaginal/ proteinuria Nocturia; tenesmus; incontinence;
urethral mucosal atrophy Increased urine residual volume; urinary tract infection
Eyes Atrophic mucosa; atrophic taste bacteriuria; atrophic vaginitis Regurgitation with aspiration;
Ears buds; anorectal incompetence Decreased salivary flow; decreased food intolerances; constipation;
Skin gastric acid production; decreased incontinence; modified appetite,
Bone marrow fibrosis; metaplasia hepatic function; decreased motility food intake, and gut motility
False-negative immunological skin
Decreased height, weight, muscle Decreased bone marrow reserve; tests; false-positive laboratory
mass, and bone density decreased T-cell function; antibody immunological tests
dysfunction Loss of cartilaginous surfaces;
Osteoporosis; vertebral collapse; Loss of skeletal calcium; reduced hypertrophic changes in joints;
changes in fluid volumes elasticity in connective tissue; increased ratio of fat to muscle
decreased viscosity of synovial fluid mass; osteoporosis; failure to
Reduced brain mass; decreased thrive; loss of muscle strength
cortical cell count Altered glucose homeostasis; Hyperglycemic response to stress;
decreases in thyroid and diabetes mellitus; hyponatremia;
Decreased translucency of lens; testosterone hormones, renin and hyperkalemia; osteopenia;
decreased size of pupil; increased aldosterone production, and vitamin osteoporosis; impotence
intraocular pressure; macular D absorption; increased antidiuretic
degeneration; arcus senilis hormone Decreased nerve conduction;
Loss of auditory neurons; atrophy Decreased brain catechol and impaired cerebral and cognitive
of cochlear hair cells dopamine synthesis; impaired functions; dementia; depression;
thermal regulation sleep changes; hypothermia,
Flattening, atrophy, and hyperthermia; global sensory
attenuation in dermal collagen, Decreased accommodation; need for impairment
rete pegs, and cytoplasm of basal increased illumination; susceptibility Decreased vision, including
keratinocytes to glare color and night vision; impaired
accommodation; presbyopia
Decreased hearing, especially
higher frequency tones; decreased Loss of hearing; balance
directional discrimination; vestibular impairment with falls
dysfunction
Decreased skin thickness; risk for Decreased resistance to tears
dermo-epidermal separation; loss of
elasticity

Adapted from Erb BD, Shimizu US. Elders in the Wilderness. In: Auerbach PS, ed. Wilderness Medicine. 6th ed. Philadelphia, PA: Elsevier, Mosby; 2012: 2007-2021.

6 Critical Decisions in Emergency Medicine

Falls Anticoagulation status must be Fatigue
considered when managing any older
Trauma is the fifth leading cause of adult with evidence of head trauma or Fatigue is an early indicator of the
death in patients older than 65 years, new neurological symptoms.32 aging process and is a strong predictor
and falls are responsible for 70% of of functional limitations and adverse
accidental deaths in those 75 years and Dehydration/Electrolyte outcomes.36 A 12-year retrospective
older.26 A variety of factors, including Imbalances review of search and rescue (SAR)
osteoporosis, reduced elasticity of operations in Maine revealed fatigue
connective tissue, loss of muscle mass, Aging can blunt the thirst sensation, to be the most commonly reported
decreased flexibility, worsening vision impair renal function, and alter the nontraumatic emergency, causative in
and hearing, and impaired balance all regulation of salt and water balance, 66% of medical SAR events.37
contribute to this risk in the elderly.4 all of which puts patients an increased
Falls are of particular concern in risk for dehydration and its negative The mean age of fatigued individuals
wilderness settings, where terrain is sequelae.33 Furthermore, while a healthy appeared to be higher than that of the
often uneven, many distractions exist, 30- to 40-year-old typically has a general SAR patient population (49
and extraction to definitive care may be total-body water (TBW) content of 55% years versus 39 years), and symptoms
complicated.27 to 60%, this amount declines to 50% most often occurred during descent
between the ages of 75 and 80 years (which is more ergonomically difficult
Soft tissue and musculoskeletal (often even lower in elderly women).34 for hikers to control) and later in
trauma are the most common injuries the day (when temperatures and
sustained in outdoor environments.28,29 Exercise-associated hyponatremia, sun exposures increase). Although
As can be surmised, a fall on a which most commonly is encountered the population studied could not be
rugged surface can result in myriad in endurance sporting events, generally characterized exclusively as geriatric, it
musculoskeletal injuries in a fragile results from a rise in free water is logical to infer that patients above the
patient. For that reason, joint intake accompanied by increased age of 55 years would report the same,
replacement manufacturers do not sodium losses, primarily in the form if not greater, rates of fatigue.
guarantee their devices for many of sweat. However, the geriatric
common outdoor activities.7 The population is at an increased risk of Infection
rising prevalence of osteopenia and hypervolemic hyponatremia, even
osteoporosis puts older adults at without significant exertion. A case The elderly are especially susceptible
especially high risk for fractures.30,31 series from a commercially guided to infections, which may manifest with
river-rafting trip in Grand Canyon atypical symptoms such as generalized
Falls also elevate the risk of serious National Park described three women weakness and confusion.38 Older adults
head injury, particularly in those between the ages of 67 to 72 who are particularly vulnerable to urinary
taking oral anticoagulants for diseases developed severe hyponatremia tract infections for a variety of reasons,
such as atrial fibrillation or venous requiring medical evacuation. In every including prostatic hypertrophy in older
thrombosis. These medications, in case, overhydration was found to be men and hysterectomies or weakened
addition to the normal cerebral atrophy the culprit.35 pelvic floor muscles in women. In the
that accompanies aging, increase wilderness, dehydration and difficulty
the risk of intracranial hemorrhage. with general hygiene can contribute
to an increased rate of infection in
n Although comorbidities must be taken into account when treating a geriatric all sites.4 Furthermore, decreased
patient in any setting, many common disorders can predispose this population immunity and skin elasticity may
to injury and escalate the risks associated with outdoor recreation. impair wound healing in geriatric
patients, predisposing them to soft
n Cardiovascular and pulmonary disease can be exacerbated in outdoor tissue infections.
settings due to increased activity and environmental exposures.
CRITICAL DECISION
n Aging can blunt the thirst sensation, impair renal function, and alter the
regulation of salt and water balance, all of which puts patients an increased What priorities must be kept
risk for dehydration and its negative sequelae. in mind when managing a
geriatric patient in an outdoor
n Extremes of temperature can cause significant morbidity for the elderly. Even environment?
in moderate temperatures, the ability of these patients to thermoregulate is
diminished. Many factors must be taken into
account when managing a patient in
n Any treatments given in the wilderness should be monitored closely for the wilderness, including environment,
clinical effectiveness and adverse effects. available supplies and equipment,
evacuation time to definitive care, and
any comorbid health conditions. In every
case, treatment should begin with an

July 2017 n Volume 31 Number 7 7

evaluation of immediate life threats. In particularly during prolonged nor prepare for being outdoors for a
an outdoor setting, this also includes evacuation times. prolonged period of time may not have
assessing the safety of the scene, both adequate supplies of their medications
for the provider and the patient. It Elderly patients often require readily available. Therefore, it is
may be necessary to relocate a patient additional resources during in-hospital important for the clinician to take a
before performing the initial assessment assessments, a special consideration that thorough history of daily medication
or treatment (eg, in cases of unstable likely extends to wilderness settings.43,44 use in the field and anticipate the
terrain or unfavorable weather). Supplemental equipment and supplies, possible consequences of missed doses.
many of which might not be directly
Even in moderate temperatures, available, may be optimal for properly Many elderly patients who have
the ability of an elderly patient to diagnosing and treating elderly victims sustained an injury or illness in
thermoregulate is diminished.39 In a in extreme environments. a wilderness setting will require
cold environment, steps must be taken evacuation and transport to definitive
to limit hypothermia; temperature What might be considered a minor care. Those who are able to ambulate
abnormalities can lead to decreased injury in a younger person may on their own should be encouraged to
cardiac output, cardiac arrhythmias, require a more intensive evaluation do so with close monitoring and support
coagulopathies, and acidosis, especially and management in a geriatric patient. if needed. Victims who cannot ambulate
in the setting of trauma.40,41 While it Wounds must be monitored closely for safely must be transported with a
may be necessary to undress or expose signs of infection; vascular disease may commercial or improvised support
a victim for assessment or treatment, all compromise healing, and anticoagulant device.50
patients (especially elderly ones) should or antiplatelet medications can increase
be covered as soon as possible to limit the risk of bleeding. In addition, any Since transport may involve
heat loss. The patient should be well treatment provided should be closely long distances, difficult terrain, or
protected from elements such as wind monitored for secondary effects. substantial time, special precautions
or rain and not in direct contact with For example, epinephrine can be a must be taken. Any type of carrying
a cold surface; this can be achieved lifesaving antidote for an anaphylactic device or backboard should be
by placing a mat or clothing between reaction; however, IV administration adequately padded to prevent skin
the patient and the ground. If there is has the potential to cause myocardial breakdown or ulcerations.51 If the
no risk for aspiration, warmed liquids infarction, cardiac arrhythmia, or patient is transported in a supine
and high-calorie foods should be given stroke in the elderly.45 position, close airway monitoring
orally. If IV fluids are available and should be performed to prevent
necessary, they should be warmed if As previously mentioned, aspiration. Any bony injuries should
possible. special attention should be paid be properly splinted and supported to
to comorbidities and prescription diminish the risk of worsening injury or
Conversely, in a hot environment, medications when managing geriatric neurovascular damage. Finally, patients
elderly patients often are unable to patients. Blood glucose should be must be adequately protected from
dissipate heat as well as younger carefully monitored in those with environmental exposures throughout
individuals, a complication that diabetes, as large fluctuations in glucose their transport.
increases the risk of dehydration can be particularly harmful in this
and hyperthermia (and subsequently population.46,47 Because hypoglycemic CRITICAL DECISION
morbidity and mortality).42 Special episodes can cause significant morbidity,
attention should be paid to volume treatment should err on the side of more What special factors should be
status to ensure adequate hydration, relaxed blood sugar targets.48,49 considered during the in-hospital
evaluation of an elderly patient
Patients who neither anticipate presenting from a wilderness
setting?
n Failing to take an adequate medical history when assessing a patient in a
wilderness environment. In general, the clinical approach
to someone transported from a
n Neglecting to evaluate a geriatric patient for significant musculoskeletal injury wilderness environment should be no
in the setting of relatively minor trauma. different than that employed with the
average emergency department patient.
n Fully immobilizing a patient for a prolonged evacuation and transport to However, there are a number of special
definitive care without adequate padding or access to the airway. considerations in an elderly patient’s
history that must be kept in mind.
n Failing to thoroughly evaluate all wounds for signs of gross contamination or
potential infection. Given that the rate of anticoagulant
use is on the rise and associated
with increased mortality related to
traumatic brain injury, every emergency

8 Critical Decisions in Emergency Medicine

CASE RESOLUTIONS electrolyte losses, and sweating. ■ CASE TWO
The patient’s oxygen saturation
■ CASE ONE Although a computed tomography scan
improved with intubation, and the of the elderly man’s cervical spine was
The elderly rafter, whose initial ECG and laboratory tests were unremarkable, a CT of the head revealed
sodium level was 116 mEq/L, unremarkable. The emergency a significant subdural hematoma with
received a diagnosis of hyponatremia. physician administered propofol, 250 mass effect. His international normalized
The hot environmental conditions, mL of IV 3% hypertonic saline, and ratio was 3.5. The emergency physician
which were exacerbated by the an infusion of normal saline. Her administered 10 mg of IV vitamin K
patient’s wetsuit, caused her to lose urine output subsequently increased. and fresh frozen plasma to reverse his
sodium through sweating; this was She was sprayed with lukewarm anticoagulation. The patient’s ankle x-ray
compounded by nausea and the water, and fans were placed at her demonstrated a trimalleolar fracture,
subsequent decrease in food and bedside to facilitate cooling. She which was irrigated, reduced, and splinted
salt intake. The patient’s use of was admitted to the ICU, where at the bedside. Arrangements were made
hydrochlorothiazide further escalated her temperature and sodium levels to have him airlifted to a tertiary care
these deficits. In addition, the rafter normalized. facility with neurosurgery capabilities.
showed symptoms of heat illness,
which contributed to her nausea,

physician should be ready to employ for supplemental oxygen therapy; the pre-hospital and hospital settings.
an evidence-based strategy for rapid however, care must be taken to avoid Common etiologies of wilderness-
anticoagulant reversal if necessary.52-54 hyperoxemia in those with myocardial
Since advanced age also is a known ischemia or COPD.62-64 Given that this related complications in this
risk factor for both falls and morbidity population is more susceptible to both population include cardiac pathologies,
and mortality related to rib fractures in heat- and cold-related illnesses, the musculoskeletal injuries, electrolyte
cases of blunt chest trauma, clinicians patient’s core temperature should be imbalances, and infections. It is
must be hypervigilant for the possible measured and corrected if needed.65,66 important to remember that chronic
development of pneumonia or acute Adrenal insufficiency also is more conditions such as cardiac and
respiratory failure in any elderly trauma common in this population; a trial pulmonary diseases may be exacerbated
patient injured outdoors.55,56 of stress-dose corticosteroids may be by recreational activities. Clinicians
appropriate in those with refractory should suspect traumatic injuries in
Any geriatric patient transported hypotension.67-69 geriatric patients who have fallen
from the wilderness with full spinal outdoors, even those with seemingly
long-board immobilization precautions Finally, given all of the compounding innocuous injuries.
(fortunately, a practice that is risks, geriatric patients with wilderness-
decreasing in frequency) should be related complaints should be closely It is crucial to take a careful
removed from the board rapidly and monitored and appropriately tested for and thorough medical history, as
assessed carefully for respiratory/airway associated illnesses, including but not comorbidities and prescription
compromise and pressure wounds.57 limited to anemia due to blood loss, medications may not only exacerbate
Finally, any open wound must be closely electrolyte abnormalities and renal health issues while in the wilderness
examined for signs of infection, given insufficiency secondary to dehydration, but also impact their subsequent
the increased risk for skin infections rhabdomyolysis and hyperkalemia from management. Specific traumatic
and contamination.58,59 crush injuries, hypothyroidism due to concerns also should be addressed,
undiagnosed illness or undertreatment, including the risk of airway/respiratory
There are several special dosing and liver damage secondary to compromise, and specific medical
accommodations that must be made hyperthermia. concerns such as the need for additional
when managing an older adult antivenom dosing.
who has been injured outdoors. In Summary
particular, antivenom may require REFERENCES
repeat administration and/or dosing The physiological and pathological
adjustments in elderly snakebite consequences of aging combined with 1. U.S. Census Bureau. Table 3 - Projections of the
victims, in whom the rare complications environmental and exertional stressors Population by Sex and Selected Age Groups for the
associated with treatment are more make the elderly particularly susceptible United States: 2015 to 2060. 2014 National Population
common.60,61 to wilderness-related illness and injury. Projections. 2014. Available at: http://www.census.
In particular, the risk for temperature- gov/population/projections/data/national/2014/
The cardiopulmonary and altitude-related illnesses should be summarytables.html. Accessed September 24, 2016.
comorbidities that often afflict the identified and rectified rapidly both in
elderly may increase a patient’s need 2. Flores AH, Haileyesus T, Greenspan AI. National
Estimates of Outdoor Recreational Injuries Treated in
Emergency Departments, United States, 2004-2005.
Wilderness Environ Med. 2008;19:91-98.

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3. Orimo H, Ito H, Suzuki T, Araki A, Hosoi T, Sawabe and patients with coronary heart disease. High Alt 50. Cooper DC, Mier TP. Litters and Carries. In: Auerbach
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28. Montalvo R, Wingard DL, Bracker M, Davidson TM. the National Association of EMS Physicians and
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Morb Mortal Wkly Rep. 2003;52(6):101-106. 29. Stephens BD, Diekema DS, Klein EJ. Recreational
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36. Avlund, K. Fatigue in older adults: an early Medical Society practice guidelines for spine
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and ischemic heart disease. Int J Sports Med. 2010;22(2):100-115. 2014 update. Wilderness Environ Med. 2013;25(4
1992;13 Suppl 1:S179-S181. 37. Welter CR, Sholl M, Strout TD, Woodard B. Suppl):S105-S117.
Epidemiology of search and rescue in Baxter State
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PH, Lennon L, Ford I, Morris RW. Effect of cold Environ Med. 2015;26(4): 549-554. nomogram to predict mortality-associated geriatric
spells and their modifiers on cardiovascular disease 38. Crossley KB, Peterson PK. Infections in the elderly. complications in severely injured geriatric patients. J
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J Cardiol. 2016;218:275-283. 39. Collins KJ, Abdel-Rahman TA, Goodwin J, McTiffin L.
Circadian body temperatures and the effects of cold 59. Quinn RH, Wedmore I, Johnson EL, et al. Wilderness
13. Jay O, Havenith G. Differences in finger skin stress in elderly and young subjects. Age Ageing. Medical Society practice guidelines for basic
contact cooling response between an arterial 1995;24(6):485-489. wound management in the austere environment:
occlusion and a vasodilated occlusion. J Appl 40. Sessler DI. Complications and treatment of mild 2014 update. Wilderness Environ Med. 2014;25(4
Physiol. 2006;100(5):1596-1601. hypothermia. Anesthesiology. 2001;95(2):531-543. Suppl):S118-S133.
41. Moffatt SE. Hypothermia in trauma. Emerg Med J.
14. Biem J, Koehncke N, Classen D, Dosman J. Out 2013;30(12):989-996. 60. Otten EJ. Venomous animal injuries. In: Rosen P,
of the cold: management of hypothermia and 42. Bunker A, Wildenhain J, Vandenbergh A, et al. Barkin R, editors. Emergency Medicine concepts
frostbite. CMAJ. 2003;168(3):305-311. Effects of air temperature on climate-sensitive and clinical practices. New York: Mosby; 1998. pp.
mortality and morbidity outcomes in the 924 – 4 0.
15. Neil HA, Dawson JA, Baker JE. Risk of hypothermia elderly; a systematic review and meta-analysis of
in elderly patients with diabetes. Br Med J (Clin Res epidemiological evidence. EBioMedicine. 2016;6:258- 61. Kang C, Kim DH, Kim SC, et al. Atraumatic splenic
Ed). 1986;293(6544):416-418. 268. rupture after coagulopathy owing to a snakebite.
43. Pines JM, Mullins PM, Cooper JK, et al. National Wilderness Environ Med. 2014;25(3):325-328.
16. National Institutes of Health. Hypothermia: a cold trends in emergency department use, care patterns,
weather risk for older people. News Releases, U.S. and quality of care of older adults in the United 62. Morris GG. Oxygen requirements: therapeutic
Department of Health and Human Services. 2009. States. J Am Geriatr Soc. 2013;61(1):12-17. indications for use with the exercising elderly. Top
Available at: https://www.nih.gov/news-events/ 44. Green SM. Emergency department patient acuity Geriatr Rehabil. 1986;2(1):70-74.
news-releases/hypothermia-cold-weather-risk- varies by age. Ann Emerg Med. 2012;60(2):147-151.
older-people. Accessed September 24, 2016. 45. Campbell RL, Bellolio MF, Knutson BD, et 63. Cabello JB, Burls A, Emparanza JI, et al. Oxygen
al. Epinephrine in anaphylaxis: higher risk of therapy for acute myocardial infarction. Cochrane
17. Richalet JP, Lhuissier FJ. Aging, tolerance to cardiovascular complications and overdose after Database Syst Rev. 2013;(8):CD007160.
high altitude, and cardiorespiratory response to administration of intravenous bolus epinephrine
hypoxia. High Alt Med Biol. 2015;16(2):117-124. compared with intramuscular epinephrine. J Allergy 64. Austin MA, Wills KE, Blizzard L, et al. Effect of high
Clin Immunol Pract. 2015;3(1):76-80. flow oxygen on mortality in chronic obstructive
18. Roach RC, Houston CS, Honigman B, et al. How 46. Krinsley JS. Glycemic variability: a strong pulmonary disease patients in prehospital setting:
well do older persons tolerate moderate altitude? independent predictor of mortality in critically ill randomised controlled trial. BMJ. 2010;341:c5462.
West J Med. 1995;162(1):32-36. patients. Crit Care Med. 2008;36(11):3008-3013.
47. van der Zwaluw NL, van de Rest O, Kessels RP, de 65. Kenny GP, Larose J, Wright-Beatty HE, et al.
19. Johnson NJ, Luks AM. High-altitude medicine. Med Groot LC. Effects of glucose load on cognitive Older firefighters are susceptible to age-related
Clin North Am. 2016;100(2):357-369. functions in elderly people. Nutr Rev. 2015;73(2):92- impairments in heat dissipation. Med Sci Sports
105. Exerc. 2015;47(6):1281-1290.
20. Luks AM, Swenson ER. Travel to high altitude 48. Gerstein HC, Miller ME, Byington RP, et al. Effects of
with pre-existing lung disease. Eur Respir J. intensive glucose lowering in type 2 diabetes. N Engl 66. Baumgartner EA, Belson M, Rubin C, Patel M.
2007;29(4):770-792. J Med. 2008;358(24):2545-2559. Hypothermia and other cold-related morbidity
49. Patel A, MacMahon S, Chalmers J, et al. Intensive emergency department visits: United States, 1995-
21. Levine BD, Zuckerman JH, deFilippi CR. Effect blood glucose control and vascular outcomes 2004. Wilderness Environ Med. 2008;19(4):233-237.
of high-altitude exposure in the elderly: the in patients with type 2 diabetes. N Engl J Med.
Tenth Mountain Division Study. Circulation. 2008;358(24):2560-2572. 67. Chen YC, Lin YH, Chen SH, et al. Epidemiology
1997;96(4):1224-1232. of adrenal insufficiency: a nationwide study of
hospitalizations in Taiwan from 1996 to 2008. J Chin
22. Centers for Disease Control and Prevention. The Med Assoc. 2013;76(3):140-145.
State of Aging and Health in America 2013. Atlanta,
GA: Centers for Disease Control and Prevention, 68. Boonen E, Van den Berghe G. New concepts to
US Dept of Health and Human Services, 2013. further unravel adrenal insufficiency during critical
Available at: http://www.cdc.gov/aging/pdf/ illness. Eur J Endocrinol. 2016;175(1):R1-R9.
state-aging-health-in-america-2013.pdf. Accessed
September 24, 2016. 69. Arlt W. The approach to the adult with newly
diagnosed adrenal insufficiency. J Clin Endocrinol
23. Chodzko-Zajko WJ, Proctor DN, Fiatarone Singh Metab. 2009;94(4):1059-1067.
MA, et al. American College of Sports Medicine
position stand. Exercise and physical activity ADDITIONAL READING
for older adults. Medicine & Science in Sports &
Exercise. 2009;41(7):1510-1530. Erb BD, Shimizu US. Elders in the Wilderness. In:
Auerbach PS, ed. Wilderness Medicine. 6th ed.
24. Burtscher M, Pachinger O, Mittleman MA, Ulmer Philadelphia, PA: Elsevier, Mosby; 2012: 2007-2021.
H. Prior myocardial infarction is the major risk
factor associated with sudden cardiac death during
downhill skiing. N Engl J Med. 2000;21(8):613-615.

25. Levine BD. Going high with heart disease: the
effect of high altitude exposure in older individuals

10 Critical Decisions in Emergency Medicine

The LLSA
Literature Review

By Ellen Vollmers, MD, PhD, and Andrew J. Eyre, MD
Massachusetts General Hospital, Brigham and Women’s Hospital, Harvard Affiliated
Emergency Medicine Residency, Boston, MA

Treatment of Venous
Thromboembolism

Wells P, Forgie M, Rodger M. JAMA. 2014;311(7):717-728.

Venous thromboembolism (VTE) for international normalized ratio anticoagulation is contraindicated.
encompasses deep vein thrombosis monitoring. Reversal agents are available Studies support long-term treatment
(DVT) and pulmonary embolism for heparin and VKA anticoagulation;
(PE), two common and potentially however, warfarin does not appear to for a minimum of 3 months, which is
fatal conditions for which the improve outcomes in patients with post- sufficient in the setting of provoked VTE.
approaches to treatment (most often reversal bleeding complications. Unprovoked and malignancy-related
anticoagulation and thrombolysis) VTE carry a significantly higher risk
are not without significant risks. The Acute monotherapy options include of recurrence. Extended or indefinite
referenced article, which aims to provide unfractionated heparin, LMWH (unfrac­ therapy may be considered; however,
the best evidence-based approach to tiona­ ted heparin in renal impairment), further research is needed to clarify
the treatment of VTE, is a compilation fondaparinux, and rivaroxaban. VKAs which patients are most appropriate for
of data from Cochrane reviews, meta- require a heparin bridge to therapeutic such a course.
analyses, and clinical and randomized levels. Thrombolysis should be saved for
controlled trials. the treatment of DVT at immediate risk Although most cases of DVT can be
for gangrene or limb loss and patients treated on an outpatient basis, admission
Patient management is divided into with PE with hemodynamic compromise. should be considered for patients with
three phases: acute (initial 5 to 10 days), These approaches provide no mortality severe symptoms, renal impairment,
long-term (end of acute phase to 3 to 6 benefit and increase the risk of bleeding high bleeding risk, or difficult social
months), and extended (beyond the 3- to complications significantly. Inferior circumstances. Clinical decision rules
6-month long-term phase). Available vena cava filters are associated with an also can be used to identify PE cases that
anticoagulants include unfractionated increased risk of recurrent DVT and are appropriate for outpatient care —
heparin; low-molecular weight should be saved for patients in whom an approach that can reduce costs and
heparin (LMWH); indirect factor Xa hospital admission rates substantially.
inhibitors (eg, fondaparinux); vitamin K
antagonists (VKAs), especially warfarin; KEY POINTS
and newer oral anticoagulants (OACs),
including direct factor Xa inhibitors and n In addition to heparin, rivaroxaban and fondaparinux are approved for acute
factor IIa inhibitors. monotherapy.

While these agents demonstrate n Recommendations regarding the ideal duration of VTE treatment remain
similar safety and efficacy for long-term unclear. Clinicians should carefully consider the potential risks and benefits of
treatment (with a preference for LMWH, extended therapy.
specifically in malignancy-related cases),
each has its own limitations. Heparin n While associated with improved vein patency, thrombolysis does NOT reduce
requires daily subcutaneous injections, mortality and increases the risk of bleeding; it should be reserved for the most
and VKAs require frequent clinic visits severe VTE cases.

n Uncomplicated DVT often can be treated at home. Refer to clinical prediction
rules to identify PE patients who may be appropriate candidates for outpatient
therapy.

Critical Decisions in Emergency Medicine’s series of LLSA reviews features articles articles from ABEM’s 2017 Lifelong Learning and
Self-Assessment Reading List. Available online at acep.org/llsa and on the ABEM website.

11July 2017 n Volume 31 Number 7

By Ahmad Mohammadieh, MD

Dr. Mohammadieh is a resident
at Orange Park Medical Center
in Orange Park, Florida.

Reviewed by Steven J. Warrington, MD, MEd

Arthrocentesis can be performed either
diagnostically (eg, to analyze and culture synovial
fluid) or therapeutically (eg, to alleviate the pain
associated with increased synovial pressure).
Radiohumeral (elbow) arthrocentesis can be used
to diagnose suspected septic arthritis, confirm
the etiology of joint inflammation (eg, gout,
pseudogout, rheumatoid arthritis), decrease
symptoms, and aid recovery in patients with
significant hemarthrosis.

The Critical Procedure

ELBOW ARTHROCENTESIS (LATERAL APPROACH)

CONTRAINDICATIONS Risks and Benefits Alternatives

n Presence of cellulitis or cutaneous/ Improved joint mobility, pain Serum markers can be used to
subcutaneous abscess on physical relief, and diagnostic accuracy diagnose autoimmune processes
examination summate the benefits of elbow such as rheumatoid arthritis, and a
arthrocentesis. Primary risks of the thorough physical examination and
n (Relative) Bacteremia procedure include hemarthrosis and laboratory studies can help identify
the introduction of infection into other inflammatory diseases such as
n (Relative) History of coagulopathy the joint space, which can cause gout. There are no true alternatives
significant problems in patients to arthrocentesis for ruling out septic
n (Relative) Prosthetic joints in the with prosthetic joints. Repeated arthritis. Pain secondary to joint effusion
emergency setting; discuss with injections of steroids can lead to can be managed using nonsteroidal anti-
an orthopedic surgeon bone and joint destruction and inflammatory drugs.
instability, and may increase the
risk of reactions secondary to the Reducing Side Effects
steroid itself. Procedural pain also
should be considered. The use of sterile technique
should decrease the risk of infection.
Local anesthesia with lidocaine or
ethyl chloride spray can decrease any

12 Critical Decisions in Emergency Medicine

procedure-related discomfort. The risk are at greater risk of peri- and post- and/or superior ulnar collateral artery
of hemarthrosis also may be minimized procedure bleeding, especially if taking injury.
by obtaining a thorough medical history supratherapeutic doses. However,
to rule out coagulopathy. Ultrasound patients with international normalized The clinician may consider injecting
guidance can be used when the ratios up to 4.5 do not appear to be anesthetic into the joint to alleviate
identification of anatomical landmarks in significant danger. The risk of pain and help facilitate the physical
is difficult secondary to a large effusion, hemorrhage in those taking aspirin and examination. Corticosteroids also
body habitus, etc. clopidogrel is comparable to that of may be injected into joints and may be
nonanticoagulated patients. more beneficial in those with arthritic
Special Considerations components. It is important to be
The lateral angle of approach is aware that crystal-containing steroid
Coagulation studies are advised preferred over the medial approach, preparations may cause transient, but
in patients taking warfarin, who secondary to the risk of ulnar nerve self-limited, synovitis flares.

TECHNIQUE Triceps brachii Humerus
Brachialis
APPROACH Oleocranon fossa
Tendon of Biceps brachii
1. Obtain patient consent, explain triceps brachii Body of humerus
the procedure, and answer all Coronoid fossa
questions. Humeral trochlea Joint capsule of
Oleocranon humero-ulnar joint
2. Notify the staff and collect Coronoid process
required equipment. Consider Subcutaneous of ulna
and prepare required supplies (eg, oleocranon bursa
therapeutic agents and specimen Pronator teres
tubes). Major trochlear
notch of ulna
3. Flex the elbow to 90° with the Articular cavity of
patient seated in an upright humero-ulnar joint
position, and rest the pronated Humero-ulnar joint
forearm palm-side down.
Ulnar
4. Confirm anatomical landmarks
with ultrasonography if available. 9. Label the entry site with a sterile marker.
10. Insert the needle perpendicularly to the skin and direct it toward the
5. Prepare the skin surface with
povidone-iodine solution or joint space; the depth will depend on the size of the effusion. A 22-gauge
chlorhexidine, and position the needle and 5-mL syringe should be adequate.
sterile drape to expose only the 11. Aspirate gently and continuously, and inject therapeutics if desired.
prepped surface. 12. Remove the needle and distribute the fluid among specimen tubes for
analysis.
6. Inject lidocaine subdermally 13. Apply pressure with sterile gauze to control any post-procedure bleeding.
at the aspiration point of entry 14. Dispose of needles appropriately in a sharps container.
(using a 25-gauge needle and
5-mL syringe). It is important
to avoid injecting into the joint
space, as this may interfere with
the fluid analysis.

7. Identify and label the olecranon
process, lateral epicondyle, and
head of the radius with a sterile
marker.

8. Palpate (wearing sterile gloves)
for a depression in the middle
of the triangle formed by the
anatomical landmarks mentioned
above.

13July 2017 n Volume 31 Number 7

An 83-year-old with dyspnea.

The Critical ECG

Atrial fibrillation with rapid ventricular response, rate 170, bifascicular block By Amal Mattu, MD, FACEP

(right bundle branch block [RBBB] and left anterior fascicular block [LAFB]), Dr. Mattu is a professor, vice chair, and
left ventricular hypertrophy (LVH), lateral ischemia. The three main diagnostic director of the Emergency Cardiology
considerations with irregularly irregular tachycardias are atrial fibrillation, multifocal Fellowship in the Department of
atrial tachycardia, and atrial flutter with variable atrioventricular conduction. The Emergency Medicine at the University
latter two diagnoses are characterized by discernable P waves, which are absent of Maryland School of Medicine in
Baltimore.

in this case. Widening of the QRS complex is caused by a RBBB, diagnosed based

on the presence of an rsR’ pattern in the right precordial leads and a wide S wave in the lateral leads I, V5-V6. LAFB also is diagnosed
based on the leftward axis, the qR complexes in I and aVL, and rS complexes in III. LVH is diagnosed based on the R-wave amplitude

in aVL >11 mm. Whereas slight ST-segment depression in the right precordial leads may be a normal finding in the presence of

RBBB, the ST-segment depression noted in the lateral leads V4-V6 is not normal, and suggests lateral ischemia.

AB Atrial fibrillation with rapid ventricular response
and abnormally widened QRS complex.

A. Atrial fibrillation with bundle branch block
Atrial fibrillation with preexisting RBBB. Note the
irregular rhythm and widened QRS complex. While
the QRS complex is abnormal, its morphology does
not change significantly from beat to beat.

B. Atrial fibrillation with ventricular preexcitation
Atrial fibrillation with ventricular preexcitation (the
Wolff-Parkinson-White syndrome). In this case of atrial
fibrillation with abnormally wide QRS complexes,
there is significant variation in the morphology of the
QRS complexes from beat to beat.

From Mattu A, Brady W, ECGs for the Emergency Physician 2. London: BMJ Publishing; 2008:11,23. Reprinted with permission.

14 Critical Decisions in Emergency Medicine

Sobering
Symptoms

Alcohol Withdrawal

LESSON 14

OBJECTIVES By Jedidiah Leaf, MD, and William Musgrave, MD

On completion of this lesson, you should be able to: Dr. Leaf is an assistant professor and Dr. Musgrave is a resident physician in
1. Describe the physiology and risk factors for alcohol the Department of Emergency Medicine at UT Southwestern Medical Center/
Parkland Hospital in Dallas, Texas.
withdrawal syndrome (AWS). Reviewed by Walter L. Green, MD, FACEP

2. Explain the spectrum of alcohol withdrawal presentations. CRITICAL DECISIONS

3. Correctly identify patients who are in withdrawal and n What clinical clues should raise suspicion for
differentiate AWS from other emergent diagnoses. alcohol withdrawal?

4. Describe how to initiate the appropriate treatment and n What diagnostic tools are most reliable for
disposition for patients in alcohol withdrawal. assessing a patient with potential alcohol
withdrawal?
5. Identify and manage those at risk for severe withdrawal.
n What medications can be used for the acute
FROM THE EM MODEL management of AWS?

14.0 Psychobehavioral Disorders n Which patients with AWS can be discharged,
14.5 Organic Psychoses and which require further management?
14.5.4 Intoxication and/or Withdrawal

Alcohol dependence extends across all socioeconomic classes, affecting an estimated 8.5% of adults in
the United States.1 While excess drinking is notoriously — and quite obviously — problematic, the cessation of
alcohol can set off a cascade of equally devastating complications.2 Withdrawal, which can be mimicked by or
comingled with other disease processes, can be particularly challenging to detect (Table 1). Although only 10% of
these patients will go on to experience severe complications, clinical vigilance and a broad differential diagnosis are
required to avoid missing the disorder’s potentially life-threatening symptoms.

15July 2017 n Volume 31 Number 7

CASE PRESENTATIONS drinking “a bottle or two of wine” daily His mucous membranes are mildly
for “many years,” but has not had a dry, and the abdomen is nontender
■ CASE ONE drink in 2 days because she has been and nondistended. There are scattered
feeling ill. excoriations to his extremities.
A 52-year-old woman presents with
a cough that developed more than ■ CASE TWO No gross cranial nerve deficits or
2 weeks ago. She explains that her ophthalmoplegia are noted and he
primary care provider diagnosed her EMS arrives with a disheveled, moves all extremities equally with a
with a viral illness 1 week ago, but her agitated 48-year-old man. A bystander noticeable coarse tremor. Hyperreflexia
symptoms have worsened in the last 2 called 911 after witnessing the patient is present. A point-of-care glucose mea-
days to include thick, yellow sputum “on the ground and shaking all over.” surement is 145, a CT scan of his head
and a fever. She is nauseated and The episode reportedly lasted about 60 reveals only mild global atrophy, and a
anxious, and says she has been eating seconds and occurred shortly after the chest x-ray is normal.
and drinking less. man disembarked a cross-country bus.
He had several episodes of non-bloody ■ CASE THREE
Her vital signs are blood pressure emesis during transport, and has soiled
161/98, heart rate 112, respiratory himself. On arrival, he is alert and An otherwise healthy 38-year-old
rate 22, temperature 38.3°C (101°F), scratching at his extremities. He provides man has decided to quit drinking and
and oxygen saturation 93% on room his name and states that he has been requests detoxification from alcohol. His
air. She is tremulous, tachycardic, living in a hotel, but does not know the last drink was 8 hours ago, and he now
and tachypneic with rhonchi in the day or year. complains of a mild headache and being
right lower lobe on auscultation. She anxious and jittery. The patient explains
is alert and oriented, with a nonfocal The patient’s initial vital signs are that he has consumed about 4 to 5
neurological examination. blood pressure 190/105, heart rate 128, 12-ounce beers daily for the past several
respiratory rate 18, and temperature months. Although he is motivated to
A right lower lobe infiltrate is noted 38.5°C (101.3°F). In his travel bag, make a change, he was warned by
on the patient’s chest x-ray, confirming you find an expired prescription for friends that “going cold turkey” could
a diagnosis of community-acquired chlordiazepoxide, bottles of metformin be dangerous. The patient is sweating
pneumonia. She is given a dose of and amlodipine, and an empty 1-liter and appears anxious, but is sitting up
intravenous (IV) antibiotics; however, bottle of vodka. He is moderately in bed and is in no distress; his physical
her tachycardia fails to resolve, and tachycardic, anxious, diaphoretic, examination is otherwise unremarkable.
she appears slightly diaphoretic and tremulous, and apparently responsive His vital signs are blood pressure 132/74
more anxious and tremulous on to internal stimuli. No overt signs of and heart rate 94; his respiratory rate
reassessment. trauma or scleral icterus are noted. and temperature are normal.

Upon further questioning, the
patient confides that she has been

Alcohol is a central nervous system (CNS) to grossly altered mental status (AMS), include direct questions regarding the
depressant that increases activity at gamma- which varies according to each patient’s amount, frequency, and last use of alcohol,
aminobutyric acid (GABA) receptors, degree of dependence and the time since as well as the reason for stopping. This
resulting in a global inhibitory effect. cessation of alcohol use (Table 2). The information will help predict where the
Chronic alcohol use further results in onset of withdrawal symptoms occurs patient is on the spectrum of withdrawal.
the downregulation of GABA receptors between 6 and 8 hours after the discontin- High-risk factors include an age over 30,
coupled with an upregulation of primarily uation of alcohol, peaking at 72 hours and history of daily alcohol use, prior with-
excitatory N-methyl-D-aspartate (NMDA) resolving at 5 to 7 days. Initial complaints drawal symptoms or seizures, and previ-
receptors.3 When the substance is withheld, include anxiety, irritability, nausea/vom- ous episodes of delirium tremens (DT).
these compensatory changes are no longer iting, insomnia, headache, tremulousness,
mitigated by the presence of alcohol, diaphoresis, tachycardia, palpitations, The patient’s reason for abstinence
triggering a state of excessive excitation hypertension, and hyperthermia. Left may guide an investigation into comorbid
that leads to the troubling symptoms of untreated, the complications of acute conditions. In many cases, a coexistent
alcohol withdrawal syndrome (AWS). withdrawal may progress to alcoholic illness such as pancreatitis, alcoholic
hallucinosis, seizures, and life-threatening gastritis, hepatitis, pneumonia, sepsis, or
CRITICAL DECISION delirium tremens.1 acute coronary syndrome prompts the
patient to forgo alcohol.
What clinical clues should raise It is important to obtain a complete
suspicion for alcohol withdrawal? history from the patient and any available In addition, there are a number of
collateral sources (eg, friends, family, or clinical screening tools that can help
Alcohol withdrawal syndrome encom- EMS); such details will help guide the determine a patient’s degree of alcohol
passes a broad spectrum of symptoms workup. These conversations should dependence. The CAGE screening tool
from mild tremulousness and anxiety (Table 3) has a sensitivity of 53% to

16 Critical Decisions in Emergency Medicine

77% and specificity of 80% or higher withdrawal, and a positive level cannot CRITICAL DECISION
for detecting substance abuse.2 Physical confirm the diagnosis. This information
examination findings may include must be interpreted in the context of the What medications can be used for
tachycardia, facial sweating, tremors, timing of the last drink and the history of
and psychomotor agitation in mild cases, routine alcohol intake. the acute management of AWS?
progressing to autonomic instability
with hypertension and tachycardia, An ECG should be obtained to As when managing any emergency
diaphoresis, and global confusion in evaluate for acute coronary syndrome department case, the priority when
patients with more advanced disease. and QT prolongation due to metabolic treating alcohol withdrawal should
derangements. Laboratory tests, be stabilization and treatment of any
CRITICAL DECISION including a complete blood count (CBC), underlying medical conditions. Failing
chemistries, liver functions tests, and to address withdrawal masked by other
What diagnostic tools are most coagulation studies can help elucidate the acute or chronic diseases may increase
reliable for assessing a patient with diagnosis. Serum pH and osmolality can the risk of mortality and ICU admission
potential alchohol withdrawal? be helpful if toxic alcohol (eg, methanol and the length of hospitalization.5 In the
or polyethylene glycol) ingestion is patient with altered mental status thought
Because the etiology of a patient’s suspected. Serum salicylate (ASA) and to be related to AWS (eg, DT), immediate
symptoms initially may not be clear, it is acetaminophen (APAP) levels may be dosing with the appropriate medication is
important for the clinician to entertain indicated in the undifferentiated patient necessary to prevent clinical deterioration.
a broad differential diagnosis. Initial with AMS. Chest x-rays may be warranted
management involves fluid resuscitation to assess for pneumonia in patients with The initial treatment of withdrawal
and symptomatic supportive care while fever or respiratory symptoms. of any severity focuses on reversing
a thorough clinical investigation is physiological CNS excitation. This can
initiated. Alcohol withdrawal is a clinical Spectrum of Withdrawal be achieved by using GABA agonists to
diagnosis of exclusion for which there is stabilize vital signs and prevent further
no pathognomonic test. After other etiologies of the patient’s clinical deterioration. Traditionally,
symptoms have been considered, the benzodiazepines have been used for initial
In the altered patient without a reliable Revised Clinical Institute for Withdrawal treatment, including chlordiazepoxide,
history, all causes of altered mental status Assessment (CIWA-Ar) will help stratify diazepam, lorazepam, midazolam or
must be considered, including trauma, the patient’s level of withdrawal and risk oxazepam, or a combination of long-
intracranial hemorrhage, infection, of further decompensation. The score is acting and shorter-acting drugs.
electrolyte abnormalities, metabolic based on clinical symptoms, including
derangement, thyrotoxicosis, drug nausea/vomiting, tremors, paroxysmal While there is no clear consensus
overdose, sympathomimetic toxidrome, sweating, anxiety, agitation, tactile regarding the superiority of a particular
liver failure, gastrointestinal bleeding, and disturbances, auditory disturbances, visual benzodiazepine for the treatment of AWS,
acute psychosis. Patients presenting with disturbances, headache, and orientation/ each particular agent has characteristics
fever and AMS may warrant a lumbar clouding of sensorium. that may influence physician preference
puncture to evaluate for meningitis or (Figure 4). Chlordiazepoxide, which has a
encephalitis. Mild withdrawal is defined as a score long half-life due to slowly cleared active
of 15 or less, moderate is 16 to 20, and metabolites, is believed to provide its
Any evidence of trauma or severe severe cases are confirmed by a score own taper. Due to the drug’s slow onset
headache may indicate the need for a above 20 (max. score 67).4 Care must of action, minimal euphoric effect, and
computed tomography (CT) scan of be taken to avoid applying the CIWA- oral dosing, it commonly is used in the
the head. A measurement of serum Ar inappropriately in patients whose outpatient setting and may be less likely
ethanol levels might be helpful; however, symptoms could be attributed to other to be abused. The agent often is combined
a negative test does not rule out etiologies. Of note, the tool has not been with a shorter-acting benzodiazepine as a
validated in ICU or postoperative patients. loading dose.
TABLE 1. DSM-5 Criteria for
Alcohol Withdrawal11 TABLE 2. Spectrum of Alcohol Withdrawal Syndromes1

A. Heavy and prolonged period of Syndrome Time after last
cessation or reduction of alcohol use drink to onset Symptoms

B. Two or more of the following, Initial withdrawal 6-8 hours Tachycardia, hypertension, increased temperature, tremulousness,
developing several hours to a few days symptoms anxiety, nausea/vomiting, headache, diaphoresis, palpitations
after criterion A:
• Autonomic hyperactivity Alcohol 12-24 hours Affects 7%-8% of AWS patients. Tactile hallucinations common;
• Increased hand tremor hallucinations visual and auditory are less common. Normal sensorium.
• Insomnia (hallucinosis)
• Nausea or vomiting 12-48 hours Generalized tonic-clonic seizures. Short post-ictal period.
• Transient auditory/visual/tactile Withdrawal Isolated and self-limited.
seizures
hallucinations or illusions
• Psychomotor agitation, anxiety Delirium tremens 72 hours Approximately 33% of patients with withdrawal seizures
• Generalized tonic-clonic seizures (DT) after initial progress to DT. Fluctuating disturbance in attention, aware-
symptoms ness, orientation, memory, language, visuospatial ability.
Autonomic instability required for diagnosis.

17July 2017 n Volume 31 Number 7

Intravenous diazepam has a rapid time FIGURE 1. Example Treatment Strategy for Severe or Refractory AWS8,9,12,13,16
to peak activity due to CNS penetration,

and can provide easier titration and a Identify the patient in severe withdrawal by history and
decreased risk of oversedation from dose examination. Establish IV access and resuscitate with fluids
stacking. Given the long half-life of its and IV vitamin and electrolyte repletion.

metabolites, the drug may provide its own

taper when adequate sedation is achieved.6 Initiate IV benzodiazepine therapy. Continue doses until
Lorazepam and oxazepam, which do not desired level of sedation has been reached.

have active metabolites, may be favored for

patients with decreased hepatic function IV diazepam (dose every 5-15 min): IV lorazepam (dose every 15-20 min):
(eg, the elderly and those with cirrhosis) to • 10-20 mg initial dose • 2-4 mg initial dose
achieve more consistent clearance.7 • 20 mg • 40 mg • 4 mg • 8 mg
• 80 mg • 80 mg • 16 mg • 32 mg
An alternative initial treatment

strategy uses another class of GABA

agonists to achieve the same goal. Initiate IV phenobarbital No Yes Initiate IV lorazepam
Barbiturates, specifically phenobarbital, infusion (10 mg/kg) OR bolus Controlled? infusion or continue boluses
provide the GABA agonism needed dose (65, 130, or 260 mg) as needed and admit (ICU
to reverse the CNS excitation present and consider intubation. or floor).
in AWS. Phenobarbital’s narrow OR
therapeutic index (due to respiratory Induce with propofol, intu­ Admit to the ICU for continued care; if still
depression and potential hypotension bate and start propofol drip poorly controlled, consider third-line agents
with increasing doses) can be seen as a such as dexmedetomidine (0.6-1.2 mcg/kg).
drawback; however, the long half-life of

this medication and its powerful sedative sedation (arousal with voice or minimal reevaluation (every 10-30 minutes
effects provide clear benefits, especially in stimulation, or a Richmond Agitation and initially, depending on the severity). These
cases refractory to benzodiazepines. Sedation Scale [RASS] score of 0 to -2) is reassessments can be spaced out further
the aim of therapy. An easy measurement (every 1-2 hours) once the desired level of
Trials have shown the effectiveness of of treatment efficacy in mild to moderate sedation has been achieved.11
phenobarbital as an initial therapy with withdrawal is a reduction of the CIWA-
either an IV infusion loading dose of 10 Ar score to less than 8.5 In more severe An escalating dose strategy may
mg/kg or IV bolus doses of 65, 130, or cases, a sedation goal of RASS 0 to -2 is be necessary for those who do not
260 mg.5,8 However, benzodiazepines appropriate, which is equivalent to a calm, improve initially with 1 to 2 doses of
remain the standard initial treatment in arousable patient.9 benzodiazepines (Figure 1). If the patient is
most situations, given their availability to be admitted, it is appropriate to initiate a
and relative safety; phenobarbital should A patient in mild withdrawal who symptom-based protocol in the emergency
be reserved for cases refractory to initial presents for an unrelated complaint may department based on CIWA-Ar scores,
benzodiazepine treatment. require little more than an initial dose which can be continued during admission.
of benzodiazepines (oral or IV) in the Such protocols appear to decrease the
The goal of treatment with GABA emergency department. Patients in mild amount of benzodiazepines required and
agonists is an improvement in psychomotor to moderate withdrawal (CIWA-Ar 10- shorten the period of treatment.11
symptoms, vital signs (eg, heart rate, 20) who are deemed inappropriate for
blood pressure, and temperature), and outpatient treatment or discharge will Concomitant Pathologies
mental status. When managing more require additional doses and frequent
severe withdrawal, a state of light Beyond initial symptom control with
GABA agonists, the emergency clinician

also must consider treatments for other

complications. Alcohol-dependent patients

are at high risk for vitamin and electrolyte

deficiencies and dehydration. Patients with

prolonged alcohol abuse frequently are

n Careful consideration should be given to the psychiatric patient with worsening thiamine and folate deficient, which places
hallucinations and abnormal vital signs, which may indicate withdrawal. them at risk for Wernicke encephalopathy
and anemia.
n In the patient with known heavy alcohol abuse and prior alcohol withdrawal who

appears sober, consider treatment with chlordiazepoxide upon arrival, especially Because these patients may have

if a prolonged stay is anticipated. coincident alcoholic ketoacidosis,
n Consider the empiric treatment of vitamin deficiencies and electrolyte IV or oral thiamine and folate are
important to include in the initial
abnormalities in cases of alcohol withdrawal or heavy alcohol use. resuscitation and treatment, as are
n Chlordiazepoxide poses a minimal risk for respiratory depression; consider using glucose-containing fluids (after thiamine

a higher initial dose than the common 25-mg capsule ( ≥100 mg).

18 Critical Decisions in Emergency Medicine

administration). In patients at risk for depending on their plans for follow up no other medical conditions requiring
Wernicke encephalopathy (classic triad and further alcohol consumption.9,12 intensive care.
of ophthalmoplegia, ataxia, and altered Those who do not plan to discontinue
mental status), higher doses of thiamine alcohol use and will have access to Those who fail to improve with the
(500 mg IV/IM every 8 hours for 3 days) alcohol after discharge may forgo initial or second dose of medication
should be given; these patients may need outpatient treatment as long as their will need to be more aggressively
to be admitted for repletion.10 Electrolyte symptoms are controlled at discharge. treated. This population likely includes
deficiencies (eg, low potassium or those with DTs, alcoholic hallucinosis,
magnesium) are common and should be A single dose of a long-acting alcohol withdrawal seizures, a CIWA-
treated, especially in patients requiring benzodiazepine (eg, chlordiazepoxide or Ar score above 20, and a history
hospitalization. diazepam) can be given in the emergency of severe withdrawal or substantial
department; these medications have a daily consumption. Severe cases may
CRITICAL DECISION long half-life and may provide enough require frequent reevaluation (every
of a taper. In those who will not have 10-15 minutes) and escalating doses of
Which patients with AWS can be immediate access to alcohol, a short benzodiazepines to achieve an adequate
discharged, and which require outpatient regimen of a long-acting level of sedation.
further management? benzodiazepine may be necessary to
prevent withdrawal. Psychiatric illness, Some of these patients will be
Low-Risk Withdrawal comorbid conditions, and homelessness refractory even to large doses of drugs
places patients at higher risk and may (>40 mg diazepam in 1 hour, >8 mg of
Cases that are low risk for complicated make discharge unsafe. lorazepam in 4 hours), and may require
or severe symptoms have the following treatment with adjunct medications.5
characteristics: Careful outpatient monitoring is Patients in severe withdrawal and those
• A mild CIWA-Ar score (<8) with necessary for low-risk patients who who require intubation cannot be
desire to detoxify from alcohol; this assessed appropriately with the CIWA-Ar
no medication or a single dose of can be achieved with daily primary score; management must be determined
benzodiazepines care provider follow up or outpatient or by vital sign improvements and the level
• Not clinically intoxicated inpatient rehabilitation. In such cases, it of sedation/agitation (RASS score).13 Such
• No significant comorbid conditions is reasonable to initiate a scheduled taper patients should be admitted to the ICU,
• No history of severe or complicated of chlordiazepoxide dosing (Figure 5), as they are likely to require a substantial
withdrawal (eg, DTs, seizures, as it often takes 5 to 7 days to complete amount of medication and nursing care.
alcoholic hallucinosis) the detoxification process. Alternative
Low-risk patients can be discharged treatment strategies outside of the Adjunct treatments for severe
scope of this article include gabapentin, withdrawal include benzodiazepine
TABLE 3. CAGE Questionnaire2 carbamazepine, and outpatient symptom- drips, phenobarbital, propofol, and
prompted treatment.12 dexmedetomidine. If frequent repeat IV
Have you ever felt the need to cut down boluses of medications are required, it
on your drinking? Severe Withdrawal may be beneficial to initiate an infusion of
Have people annoyed you by criticizing midazolam or lorazepam and titrate to the
your drinking? Patients can be dispositioned to the desired sedation level. Phenobarbital can
Have you ever felt guilty about floor if their vital signs improve or can be be more effective than benzodiazepines in
drinking? corrected in the emergency department this subgroup of patients.8
Have you ever felt like you needed a and they are not altered, do not require
drink first thing in the morning to steady large doses of benzodiazepines (10-20 mg Intubation may be necessary in
your nerves or help a hangover? diazepam or 2-4 mg lorazepam), can patients refractory to benzodiazepine
A score of 2 or more is 91% sensitive, tolerate 2 to 4 hours between doses after boluses or infusions and phenobarbital.
77% specific for alcoholism. a short period of observation, and have Induction and sedation with propofol
can substantially reduce the required
TABLE 4. Benzodiazepine and Phenobarbital Characteristics5,8,9 dose of benzodiazepines; the drug’s
mechanism of action directly counteracts
Agent Onset of Half-life Redose Dose Metabolism
Phenobarbital (IV) action 80–120 hrs timing
5 mins 65, 130, 260 mg Hepatic TABLE 5. Chlordiazepoxide
1–3 hrs n/a Outpatient Treatment15
10–20 hrs
bolus or 10 mg/kg
30–55 hrs
infusion

Midazolam (IV/IM) 2–5 mins Every 5 mins 2–4 mg Hepatic (active) Single loading dose

Lorazepam (IV) 15–20 mins Every 15–20 2–4 mg Hepatic (inactive) 5–150 mg
mins 10–20 mg Hepatic (active)
Diazepam (IV) 5 mins Tapering strategy Tapering dose
Every 5–15
mins Day 1 50 mg every 6 hours

Oxazepam (oral) 120–180 mins 6–10 hrs 3–4x/day 15–30 mg Hepatic (inactive) Day 2 25 mg every 6 hours
7–13 hrs 25–100 mg Hepatic (active)
Chlordiazepoxide 30–120 mins Every 4–6 Day 3 25 mg 2x/day
(oral) hrs
Day 4 25 mg at night

19July 2017 n Volume 31 Number 7

CASE RESOLUTIONS panel revealed a potassium level of ■ CASE THREE
2.9, which was repleted; an aspartate
■ CASE ONE aminotransferase level of 160; and a The young patient’s symptoms
serum glutamic pyruvic transaminase were indicative of early alcohol
The patient was diagnosed with level of 84. The patient’s other withdrawal; he was given
alcohol withdrawal and noted to laboratory values were normal. chlordiazepoxide (50 mg), which
have a CIWA-Ar score of 19. Her helped decrease his anxiety and heart
tremulousness resolved with the Maintenance fluids, IV thiamine rate. After 2 hours of observation
administration of oral chlordiazepoxide (500 mcg), IV folate (1 mg), and in the emergency department, his
(100 mg) and IV lorazepam (2 mg). Her normal saline (2 L) were administered. vital signs remained stable and his
hypertension and tachycardia resolved The patient also received a dose of CIWA-Ar score remained less than 6.
after 2 hours of observation in the IV lorazepam; however, he remained
emergency department. She was placed tremulous and agitated and was given The patient was deemed
on the hospital’s CIWA-Ar protocol IV phenobarbital (130 mg). He remained appropriate for outpatient
and admitted for community-acquired hyperdynamic after 30 minutes and his management and was referred to
pneumonia and alcohol withdrawal. agitation did not abate, so an additional an addiction medicine clinic for
dose of phenobarbital (260 mg) was further treatment. He was prescribed
■ CASE TWO given and rapid-sequence intubation was chlordiazepoxide (50 mg every 6
performed. A propofol infusion also was hours for 1 day, followed by 25 mg
The disheveled man’s cerebral spinal initiated, titrated to RASS of 0, and the every 6 hours for the next day).
fluid studies were normal, and the patient was admitted to the ICU.
CBC was notable for hemoglobin of
12.4 with a mean corpuscular volume
of 105. A comprehensive metabolic

the CNS hyperactivity present in AWS.5 spectrum of disorders, frequently is REFERENCES
Dexmedetomidine, a central alpha-2 complicated by coexisting diagnoses.
agonist, directly counteracts the vital sign It is crucial to elicit the reason for a 1. Diagnostic and Statistical Manual of Mental Disorders
changes that accompany withdrawal and patient’s alcohol cessation. (American Psychiatric Association, 2013).
may be helpful in initial stabilization, but
has not been shown to reduce the 7-day Benzodiazepines should be used 2. Schuckit MA. Alcohol-use disorders. Lancet.
benzodiazepine requirement in ICU for the initial treatment of AWS; 2009;373(9662):492-501.
patients and may not treat the underlying escalating doses may be required. Repeat
pathophysiology of AWS.14 administration of the CIWA-Ar scale can 3. Kosten TR, O’Connor PG. Management of drug and
guide the need for additional therapy. alcohol withdrawal. N Engl J Med. 2003;348(18):1786-1795.
Summary A dose of oral chlordiazepoxide may
stave off withdrawal in patients at risk. 4. Sullivan JT, Sykora K, Schneiderman J, et al. Assessment
When managing patients with alcohol In severe cases, a protocol of escalating of alcohol withdrawal: the revised clinical institute
abuse and withdrawal, it is imperative doses of benzodiazepines can prevent withdrawal assessment for alcohol scale (CIWA-Ar). Br J
to keep a broad differential diagnosis clinical deterioration and improve Addict. 1989;84(11):1353-1357.
to avoid missing life-threatening outcomes. Consider adjunctive therapy
pathologies, as alcohol withdrawal with phenobarbital followed by propofol 5. Schmidt KJ, Doshi MR, Holzhausen JM, et al. Treatment
is a diagnosis of exclusion. Acute or dexmedetomidine in cases refractory of severe alcohol withdrawal. Ann Pharmacother.
withdrawal, which comprises a broad to treatment with benzodiazepines. 2016;50(5):389-401.

n Prescribing drugs that mask vital sign abnormalities (eg, beta-blockers, calcium 6. Weintraub SJ. Diazepam in the treatment of moderate to
channel blockers, antipyretics, paralytics) to patients with potential withdrawal. severe alcohol withdrawal. CNS Drugs. 2017;31(2):87-95.

n Missing an alternative diagnosis (eg, sepsis, ischemia, intracranial injury, 7. Peppers MP. Benzodiazepines for alcohol withdrawal
meningitis, drug overdose, etc.) due to early anchoring to withdrawal. in the elderly and in patients with liver disease.
Pharmacotherapy. 1996;16(1):49-57.
n Neglecting to include withdrawal from other CNS depressants in the differential
diagnosis of a patient with altered mental status. 8. Rosenson J, Clements C, Simon B, et al. Phenobarbital
for acute alcohol withdrawal: a prospective randomized
n Admitting a patient in alcohol withdrawal after the first or second dose of double-blind placebo-controlled study.
benzodiazepines, or underestimating the level of inpatient care required. Patients J Emerg Med. 2013;44(3):592-598.e2.
with severe complications can decompensate quickly without proper treatment.
9. Long D, Long B, Koyfman A. The emergency medicine
management of severe alcohol withdrawal. Am J Emerg
Med. 2017. doi:10.1016/j.ajem.2017.02.002.

10. Schuckit MA. Recognition and management of
withdrawal delirium (delirium tremens). N Engl J Med.
2014;371(22):2109-2113.

11. Saitz R, Mayo-Smith MF, Roberts MS, et al. Individualized
treatment for alcohol withdrawal. A randomized double-
blind controlled trial. JAMA. 1994;272(7):519-523.

12. Simpson SA, Wilson MP, Nordstrom K. Psychiatric
emergencies for clinicians: emergency department
management of alcohol withdrawal. J Emerg Med.
2016;51(3):269-273.

13. Gold JA, Rimal B, Nolan A, Nelson LS. A strategy of
escalating doses of benzodiazepines and phenobarbital
administration reduces the need for mechanical
ventilation in delirium tremens. Crit Care Med.
2007;35(3):724-730.

14. Mueller SW, Preslaski CR, Kiser TH, et al. A randomized,
double-blind, placebo-controlled dose range study of
dexmedetomidine as adjunctive therapy for alcohol
withdrawal. Crit Care Med. 2014;42(5):1131-1139.

15. Medically supervised alcohol withdrawal in the
ambulatory setting - UpToDate. Available at:
https://www-uptodate-com.foyer.swmed.edu/
contents/medically-supervised-alcohol-withdrawal-
in-the-ambulatory-setting?source=search_result
&search=librium%20taper&selectedTitle=3~150#H22.
Accessed April 22, 2017.

16. Lorentzen K, Lauritsen AØ, Bendtsen AO. Use of propofol
infusion in alcohol withdrawal-induced refractory delirium
tremens. Dan Med J. 2014;61(5):A4807.

20 Critical Decisions in Emergency Medicine

The Critical Image

CASE By Joshua S. Broder, MD, FACEP

A 32-year-old woman, G2P0010, presents with vaginal bleeding. Her last Dr. Broder is an associate professor and the
menstrual period was 6 weeks earlier; she reports having a missed spontaneous residency program director in the Division
abortion about 3 weeks ago, for which she underwent a dilatation and extraction of Emergency Medicine at Duke University
procedure. She now complains of several hours of brown vaginal spotting. She Medical Center in Durham, North Carolina.
denies fever or significant abdominal pain.
KEY POINTS
Her vital signs are blood pressure 137/74, heart rate 92, temperature 37.0°C (98.6°F),
respiratory rate 16, and oxygen saturation 99% on room air. She is well appearing n Cervical ectopic pregnancy, defined
with a nontender abdomen. Her pelvic examination reveals a small amount of dark as the presence of an implanted
blood in the vaginal vault, with a normal closed cervix and no adnexal masses or fertilized ovum in the endocervical
cervical motion tenderness. The patient’s hematocrit level is 37.9%, blood type is canal below the level of the internal
B positive, and urinalysis is negative for infection. Her urine is positive for human cervical os, is rare (accounting
chorionic gonadotropin (hCG), and her quantitative serum hCG is 6315 mIU/mL. for <0.1% of pregnancies).1
The condition can be mistaken
A transvaginal ultrasound is performed. sonographically for a spontaneous
abortion in progress, or even a low-
Fluid-filled structure lying intrauterine pregnancy.
in cervical canal
n Significant hemorrhage from
Uterine fundus Uterine body Cervix cervical ectopic pregnancy can be
life-threatening, particularly when
A. Transvaginal ultrasound on the date of emergency department the diagnosis is missed. Three-
presentation. A fluid-filled structure is present in the endocervical canal, dimensional ultrasonography and
whereas no intrauterine pregnancy is visible within the body of the uterus. magnetic resonance imaging have
The appearance could suggest a spontaneous abortion in progress, with been advocated when the diagnosis
products of conception being passed into the cervix. Alternatively, the is uncertain, although the rarity
findings could represent cervical ectopic pregnancy. of the condition has prevented
systematic study.
Fluid-filled structure B. Transvaginal
in cervical canal ultrasound CASE RESOLUTION
1 week later.
Yolk Sac The fluid-filled Obstetrics was consulted
structure in the and the patient was admitted
Cervix endocervical for monitoring of possible
canal has spontaneous abortion or cervical
enlarged; a ectopic pregnancy. Her serum
yolk sac is hCG level continued to rise, and
now visible, methotrexate therapy was initiated.
confirming Despite treatment, the patient’s
cervical ectopic hCG values climbed over the next
pregnancy. week, and a repeat transvaginal
ultrasound (Image B) confirmed
Uterine fundus Uterine body a cervical ectopic pregnancy.
Soon thereafter, hCG values
declined; the patient did not
require surgical therapy.

1Singh S. Diagnosis and management of cervical ectopic
pregnancy. J Hum Reprod Sci. 2013;6:273-276.

21July 2017 n Volume 31 Number 7

CME Reviewed by Lynn Roppolo, MD, FACEP

QUESTIONS Qualified, paid subscribers to Critical Decisions in Emergency Medicine may receive
CME certificates for up to 5 ACEP Category I credits, 5 AMA PRA Category 1
Credits™, and 5 AOA Category 2-B credits for completing this activity in its entirety.
Submit your answers online at acep.org/newcriticaldecisionstesting; a score of 75%
or better is required. You may receive credit for completing the CME activity any time
within three years of its publication date. Answers to this month’s questions will be
published in next month’s issue.

1 Which of the following medical events is most 6 You are rescuing an elderly patient injured during a
common among elderly participants in outdoor hiking trip; the ambient temperature is 13°C (55°F).
activities? After assessing for major safety and life threats to
the victim, what step should be taken to prevent
A. Acute coronary syndrome further morbidity?
B. High-altitude illnesses, including acute mountain
A. Keep the patient exposed during transport to
sickness monitor for chest rise
C. Musculoskeletal and soft tissue injuries
D. Pulmonary and airway emergencies B. Place the victim on top of an insulated mat to
prevent heat loss
2 How might cardiovascular disease contribute to
heat-related illness among the elderly? C. Prophylactically intubate for airway protection
during transport
A. Uncontrolled hypertension increases the
incidence of heat stroke D. Spray the patient with warm water to increase
body temperature
B. Cardiogenic pulmonary edema increases
insensible fluid losses through respiration 7 Your search team has reached and assessed a
71-year-old man who must be carried out on a litter.
C. Cardiac dysfunction decreases the ability to He appears to be at minimal risk for aspiration, and
redistribute blood appropriately for cooling the evacuation is estimated to take 2 hours. What
important step is required?
D. Peripheral vascular disease decreases the
likelihood of heat syncope by shunting blood A. Apply padding between the patient and the litter,
centrally especially around bony prominences

3 To what elevation can patients with asymptomatic B. Provide a method for the patient to eliminate
underlying diseases travel without an increase in excrement without soiling himself
morbidity or mortality?
C. Provide the patient with a seal around his face to
A. 1,000 meters prevent heat and insensible water loss
B. 2,500 meters
C. 3,500 meters D. Suture all open wounds to prevent infection
D. 5,000 meters
8 What intervention should be implemented before
4 An elderly tourist presents to an emergency evacuating a patient from the wilderness with a
department located 3,000 meters above sea level long bone injury and no evidence of neurovascular
with acclimation-related complaints. What finding compromise?
might be expected?
A. Apply a compression dressing at the site of injury
A. Asymptomatic bradycardia B. Continuously feel for distal pulses during transport
B. Physiological bradypnea C. Reduce any apparent displaced fractures
C. Physiological hyperthermia D. Splint across the site of injury, including the joints
D. Uncontrolled hypertension
above and below
5 Which electrolyte abnormality poses the greatest
risk to elderly patients in outdoor settings? 9 An active 68-year-old man with a history of
hypertension arrives via ambulance after prolonged
A. Hyperkalemia due to high-altitude renal failure extrication in a wilderness environment. You assess
B. Hypernatremia due to eating more processed, for immediate life threats; examine his head, chest,
abdomen, and extremities; and remove him from
high-sodium foods the spinal board. What should be the next step?
C. Hypokalemia due to high alcohol use in
A. Active rewarming, as all geriatric patients
wilderness settings presenting from wilderness are hypothermic
D. Hyponatremia due to overhydration from drinking
B. Assess for skin lesions, given the transport
hypotonic fluids C. Initiate a CT scan of the head
D. Leave wounds open, as they should be assumed

to be contaminated

22 Critical Decisions in Emergency Medicine

1 0 What emergency department intervention should 1 6 A 44-year-old man with a history of alcohol abuse
be considered for an elderly patient brought in from presents with withdrawal symptoms. His last drink was
the wilderness with refractory hypotension? 20 hours ago. He is complaining of anxiety, “seeing
shadows,” and feeling “like bugs are crawling” on his
A. A trial of stress-dose steroids skin. He has tachycardia and mild hypertension but is
B. Maintaining the patient in an upright seated oriented to himself, his present location, and the date.
He has mild diaphoresis and tremulousness. What
position at all times syndrome should be suspected?
C. Repeat fluid boluses until blood pressure
A. Alcoholic hallucinosis
normalizes B. Alcohol withdrawal seizures
D. Therapeutic hypothermia to preserve brain C. Delirium tremens
D. Mild alcohol withdrawal
function
1 7 You are treating a patient with a CIWA-Ar score of
11 Alcohol withdrawal symptoms stem from which of 12; IV lorazepam (20 mg over 3 hours) is required
the following mechanisms? for symptom control. Once the vital signs have
normalized, what is the best disposition?
A. Downregulation of acetylcholine receptors
B. Downregulation of NMDA receptors and A. Admit to telemetry ward bed
B. Admit to the intensive care unit
upregulation of GABA receptors C. Discharge
C. Upregulation of NMDA receptors and D. Observe for 2 hours in the emergency department

downregulation of GABA receptors 18 A 52-year-old woman with a history of complicated
D. Upregulation of dopaminergic receptors alcohol withdrawal presents with AMS. Her vital signs
are blood pressure 90/58, heart rate 125, respiratory
12 A 49-year-old man arrives via ambulance with rate 24, and temperature 38.9°C (102°F). She appears
altered mental status (AMS) following a witnessed diaphoretic and pale, is difficult to arouse with verbal
seizure. His GCS score is 14 on arrival, and a stimulus, and is oriented to person only. An ECG
hematoma is noted on the parietal scalp. He states demonstrates sinus tachycardia, normal intervals, and
his last drink was 2 days ago and denies a history of nonspecific T-wave changes. IV fluids and oxygen are
prior seizures. Vital signs are normal, and his blood administered, and laboratory tests are initiated. What
glucose is 95. Which test is indicated next? treatment should be given next?

A. CT angiography of the chest A. Broad-spectrum antibiotics
B. CT of the head B. Cardiac catheterization
C. Electroencephalogram C. IV benzodiazepines
D. MRI of the brain with and without gadolinium D. Physostigmine

13 Approximately what percentage of patients 19 Which of the following medications does not treat the
experience a progression from withdrawal seizures underlying pathophysiology of AWS?
to delirium tremens?
A. Dexmedetomidine
A. 5% B. Diazepam
B. 15% C. Phenobarbital
C. 33% D. Propofol
D. 50%
2 0 At what point do symptoms appear after the cessation
1 4 Which of the following agents should be included in of chronic alcohol use?
the treatment of a patient with an isolated alcohol
withdrawal seizure? A. Onset at 2 to 4 hours, peaking at 24 hours
B. Onset at 4 to 6 hours, peaking at 48 hours
A. 3% saline solution C. Onset at 6 to 8 hours, peaking at 72 hours
B. Levetiracetam D. Onset at 12 to 24 hours, peaking at 72 hours
C. Lorazepam
D. Phosphenytoin

1 5 Which agent would be most effective for treating an
altered, agitated patient with suspected AWS who
does not have IV access?

A. Chlordiazepoxide (PO)
B. Haloperidol (IM)
C. Lorazepam (IM)
D. Midazolam (IM)

ANSWER KEY FOR JUNE 2017, VOLUME 31, NUMBER 6

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
BCDDBCCADACAACDADB BA

23July 2017 n Volume 31 Number 7

Drug Box Tox Box

TICAGRELOR VOLATILE SUBSTANCE ABUSE

By Levi Filler, DO, and Frank Lovecchio, DO, MPH, FACEP, By Bryan Corbett, MD, and Christian A. Tomaszewski, MD,
Maricopa Medical Center, Phoenix, Arizona MS, MBA, FACEP, University of California, San Diego

Ticagrelor is an antiplatelet medication used for the prevention of Volatile hydrocarbons are ubiquitous in various household
thrombotic events. Guidelines issued by the American College of items, including spray paints, solvents, glues, and lighter fluid.
Cardiology/American Heart Association in 2016 recommend ticagrelor over Inhalation of the fumes, sometimes referred to as huffing or
clopidogrel for the management of patients with acute coronary syndrome sniffing, produces CNS depression and euphoria similar that
(ACS) and a coronary stent, and for those with non-ST elevation ACS caused by inhaled anesthetics. The duration of action is variable
(NSTE-ACS) treated with medical therapy alone (class IIa LOE). but generally is short lived (ie, 10s of minutes). Of most concern
is sudden death from ventricular dysrhythmia (due to myocardial
Mechanism of Action (MOA) irritability accompanied by a large catecholamine surge).
The drug reversibly binds adenosine diphosphate (ADP) P2Y12-class Although halogenated hydrocarbons are implicated, basic
receptors and inhibits platelet signal transduction and aggregation. hydrocarbons (eg, butane), also can cause poisoning.
Antagonizing P2Y12 leads to an inhibition of G protein and adenylyl cyclase,
resulting in a decrease in coupled downstream effects. Clinical Presentation
• Neurological: Euphoria, dizziness, CNS depression
Indications • Cardiac: Palpitations or syncope
Ticagrelor often is used in combination with acetylsalicylic acid for dual • Pulmonary: Dyspnea with acute hypoxia, rarely pneumonitis
antiplatelet therapy in patients with ACS or ischemic stroke. It has been • Skin: “Huffer’s eczema” from chronic defatting
shown to reduce the rate of cardiovascular death, myocardial infarction • Specific agents:
(MI), and stroke in patients with ACS or a history of MI, and may reduce the
rate of stent thrombosis in those who have been stented for ACS. ­— Toluene: muscle weakness due to hypokalemia from renal
tubular acidosis
Adult Dosing — ACS (STEMI and NSTEMI)
Loading dose: 180 mg PO/NG/OG (with a loading dose of aspirin 325 mg) ­— Carbon tetrachloride: hepatitis
Maintenance dose: 90 mg 2x/day PO; maintenance dosing can be initiated ­— Methylene chloride: metabolized to carbon monoxide
12 hours after initial dose (with a maintenance dose of aspirin 75-100 mg). —­ Fluorinated hydrocarbons: perioral freeze burns from
Reduce to 60 mg 2x/day after 12 months of initial therapy.
Note: No dose reduction recommended in patients with renal or mild hepatic expanding gases
impairment; use caution with moderate hepatic impairment and avoid if severe.
No pediatric dose has been established. Laboratory Evaluation
• Agents cannot be detected on routine screens.
Side Effects • Laboratory and imaging tests as indicated by clinical context;
More frequent: Dyspnea, bleeding, ECG abnormalities, dizziness, syncope
nausea, increased serum creatinine consider electrocardiography, chest x-ray, and comprehensive
Less frequent: Angioedema, atrioventricular block, gout, bradycardia, metabolic panel to assess kidney and liver function.
hypersensitivity reaction, skin rash
Treatment
Contraindications • Treatment largely is supportive with attention paid to
Hypersensitivity to drug, active bleeding or history of intracranial bleeding,
reduced liver function, combined with drugs that influence the activity of ABCs; cardiac monitor if symptomatic; correct any fluid or
the liver enzyme CYP3A4. electrolyte (hypokalemia) disturbances.
• Beta-blockers, specifically propranolol and esmolol, have
Precautions been used to treat ventricular dysrhythmias.
May increase the risk of TIMI major bleeding (but not fatal or intracerebral • There is no role for enhanced decontamination/elimination.
hemorrhage). Doses of aspirin >100 mg per day can reduce efficacy. Has
been associated with mild to moderate dyspnea. Pregnancy category C Disposition
(unknown if excreted in breastmilk). Patients who have returned to baseline mental status and have
no respiratory or cardiac complications may be discharged.
Symptomatic patients can be admitted for cardiac monitoring.