TRAUMA, BIOTERRORISM, AND NATURAL DISASTERS

Question 1

Trauma is the most common cause of death in what age group?

Answer 1

○ Trauma is the leading cause of death among those younger than 45 years old.
○ An estimated 5 million people worldwide die each year from injuries

Question 2

What resources are available at hospitals specializing in trauma (e.g., “level 1”
trauma centers)?

Answer 2

○ Specialized trauma centers maintain the staff, space, and supplies required to
provide immediate trauma care.
○ This includes a number of different physician specialties (emergency medicine, trauma surgery, anesthesiology, neurosurgery, diagnostic and interventional radiology, orthopedic surgery), nursing staff, dedicated patient care areas in the emergency department, operating rooms, intensive care unit (ICU), immediate diagnostic resources, and a blood bank.
○ In the United States, a hospital designated as a level 1 trauma center must be able to provide such services on an immediate basis 24 hours a day

Question 3

In reference to traumatic injuries, what is “The Golden Hour”?

Answer 3

○ “The Golden Hour” refers to the first hour after a patient sustains major injuries.
○ Most trauma-related deaths occur during this first hour, usually as a result of uncontrolled hemorrhage.
○ Early recognition and treatment of shock is therefore a major priority in acute trauma care.

Question 4

What are the management priorities when caring for a trauma patient?

Answer 4

○ The immediate priorities in acute management of trauma patients are to keep the patient alive, identify life-threatening injuries, stop any ongoing bleeding, and provide definitive treatment as early as possible

Question 5

What is ATLS? What is its relevance to all trauma providers?

Answer 5

ATLS is the acronym for the Advanced Trauma Life Support course that is administered worldwide through the American College of Surgery’s Committee on
Trauma.
ATLS is important to trauma providers because it provides a standardized algorithm that can be universally applied to all trauma patients, regardless of a provider’s background or available resources.
While trauma providers may vary from the basic ATLS algorithm based on availability of certain resources, knowledge of ATLS is useful to all trauma providers because it establishes a baseline for trauma
management and a universal language (e.g., primary survey, secondary survey, ABCDEs) that providers all share

Question 6

What are the “ABCDEs” of trauma?

Answer 6

○ The “ABCDEs” of trauma refers to the appropriate sequence of priorities in trauma management:
Airway,
Breathing,
Circulation,
Disability (neurologic status),
Exposure/Environment.
○ Providers must immediately assess the ABCDEs, in sequence, when initially evaluating a trauma patient.
○ Compromise at any step should be corrected before moving on to the next

Question 7

A motor vehicle accident victim arrives with an endotracheal tube in situ, a blood
pressure of 80/60, heart rate 120, and an obvious right ankle deformity with
exposed bone. What is the first step in management of this patient?

Answer 7

Acute management of any trauma patient must begin with confirmation of a patent
airway, therefore the first step in managing this patient is to confirm proper position
of the endotracheal tube (ETT). Capnography, auscultation of bilateral breath
sounds, pulse oximetry, direct laryngoscopy, arterial blood gases, and fiber-optic
bronchoscopy are all commonly used to confirm that an “in situ” ETT is, in fact,
in the trachea.

Question 8

List the indications for endotracheal intubation after life-threatening trauma.

Answer 8

Indications for endotracheal intubation after life-threatening trauma include inadequate airway protection, impending loss of airway (e.g., inhalational injury, expanding neck hematoma), laryngeal or tracheal injury, inadequate ventilation or oxygenation, severe head injury, and need for surgery under general anesthesia

Question 9

Prior to the arrival of a trauma patient, what should providers do to prepare for possible endotracheal intubation?

Answer 9

Management of a trauma patient should include prior preparation of functioning suction, oxygen delivery devices (oxygen source, breathing circuit, ventilator), airway equipment (face mask, oral/nasal airways, intubation equipment), pharmaceuticals (for intubation of the trachea and management of hemodynamics), intravenous access with fluids and tubing, monitors, and personal protective equipment.
Assistants to help with cervical spine and aspiration precautions should be designated, as well as equipment and personnel needed for a surgical airway if endotracheal intubation cannot be performed.

Question 10

What intravenous medications are most commonly used to intubate the trachea in severely injured patients?

Answer 10

Etomidate or ketamine are most often used as the intravenous induction agent for severely injured patients, given the risk of hypovolemic shock and hemodynamic instability with induction.
Propofol can be used for induction of stable patients without signs of shock.
Succinylcholine is the most commonly used neuromuscular
blocking agent to quickly provide optimal conditions for rapid sequence intubation of the trachea. Succinylcholine can be safely used in trauma and burn patients within the first 24 hours after injury, provided no other contraindications exist

Question 11

In the context of traumatic brain injury, what is a plateau wave?

Answer 11

A plateau wave is an abrupt and sustained increase in intracranial pressure that can occur in patients with traumatic brain injury, often in response to painful stimulation.
This severe intracranial hypertension can last for 20 minutes before resolving, often dropping rapidly to a level lower than the previous baseline.

Question 12

How should a trauma patient’s head be positioned for asleep endotracheal intubation if the stability of the cervical spine is unknown?

Answer 12

If a patient’s cervical spine stability is unknown and the airway must be secured, asleep endotracheal intubation should proceed with the patient’s head stabilized in the neutral position on a flat, rigid surface.
Such manual, in-line stabilization should be performed by an assistant whose goal during intubation is to prevent atlanto-occipital extension during direct laryngoscopy

Question 13

In the event of airway obstruction and an inability to perform endotracheal
intubation, how should the airway be secured?

Answer 13

Inability to mask ventilate or intubate the trachea necessitates immediate invasive
intervention such as emergency cricothyrotomy or tracheotomy

Question 14

How is shock defined in trauma care? What blood pressure and heart rate values are consistent with shock?

Answer 14

Shock is defined as inadequate perfusion to vital organs.
Low, normal, and high blood pressure and heart rate can be seen in patients with shock. Compensatory mechanisms and other factors, such as pain and agitation, allow patients with shock to maintain normal or even elevated blood pressure and/or heart rate.
Decompensated hypovolemic shock, or late shock, will lead to profound
hypotension and tachycardia. Spinal shock is characterized by hypotension and bradycardia. Clinicians should therefore maintain a high level of suspicion for shock in patients with severe injuries, regardless of a normal blood pressure and heart rate.

Question 15

What are the most sensitive and specific markers of shock in trauma patients?

Answer 15

Abnormal base deficit and lactate are the best independent markers of shock after trauma.
The degree of base deficit also correlates with the severity of shock, volume deficit, morbidity, and nonsurvival.
One or both markers should be checked in all trauma patients with risk of shock.

Question 16

Into what three anatomic spaces can a trauma patient massively hemorrhage? How
would identification of orthopedic injuries limit internal bleeding?

Answer 16

Massive hemorrhage can occur into the thoracic, abdominal, or pelvic cavities.
Estimated blood loss must therefore take into account both visible hemorrhage
(at the injury scene and hospital) and potential hemorrhage into one of these three
cavities. Significant blood volume can also be lost into the thigh with certain
femoral injuries. Identification of pelvic injuries or femur fractures, with subsequent
placement of pelvic binders or long bone splints, helps to limit hemorrhage into
the pelvis and thigh, respectively.

Question 17

What degree of chest tube output requires operative intervention?

Answer 17

Operative intervention is required if more than 1500 mL of blood comes out at the
time of thoracostomy tube placement, or 200 mL per hour thereafter. This degree of
chest tube output suggests active intrathoracic hemorrhage and is defined as a
massive hemothorax. Massive hemothorax should also be assumed, until proven
otherwise, in any patient with a penetrating thoracic injury that is
hemodynamically unstable

Question 18

What is the treatment for hypovolemic shock following injury?

Answer 18

The primary treatment of hypovolemic shock is to stop any active bleeding.
Delays in identification and control of hemorrhage can be deadly and should
therefore be avoided. Fluid resuscitation is the mainstay of supportive therapy
for patients with hypovolemic shock after injury. Warmed isotonic crystalloid can
be used initially for volume resuscitation, but patients with persistent shock should
be given blood products to maintain minimum perfusion pressures until
hemorrhage is controlled. Vasopressors may be helpful in patients not responding
to fluid therapy or to induce higher blood pressure for spinal cord or cerebral
perfusion

Question 19

What is the definition of massive transfusion?
What is the significance of blood product ratios in massive transfusion?

Answer 19

Massive transfusion is traditionally defined as: greater than or equal to 10 units of blood transfused in 24 hours, equivalent to the replacement of one blood volume in an average size patient.
The unit ratios of blood products transfused may affect the likelihood of hemorrhage control and survival in injured patients requiring massive transfusion.
During a massive transfusion, many trauma centers use blood product ratios to help providers administer fluids that more closely replace the functions of a patient’s lost blood.

Question 20

What is the Glasgow Coma Scale (GCS) and how is it used to evaluate a trauma
patient?
What GCS score is considered “severe”?
Why do patients with severe traumatic brain injury (TBI) require endotracheal intubation, even if protecting their
airway?

Answer 20

The GCS is used during the initial assessment of a trauma patient to rapidly evaluate neurologic status. The GCS is calculated by assigning points based on a patient’s eye opening (1 to 4), verbal response (1 to 5), and motor response (1 to 6)
to compute a total score between 3 (worse) to 15 (best).
The GCS can then be used to categorize the severity of traumatic brain injury (TBI).
A GCS score of 8 or less is classified as “severe” TBI.
Patients with severe TBI have a high likelihood of intracranial hypertension, possibly with midline shift or brain herniation.
Endotracheal intubation and control of ventilation is therefore needed to
quickly diagnose and treat any life-threatening intracranial hemorrhage.

Question 21

What secondary insults should be avoided in patients with traumatic brain injury?

Answer 21

Hypotension, hypoxia, hyperthermia, and sustained intracranial hypertension should be avoided in traumatic brain injury patients, as these secondary insults are associated with worse outcomes in brain-injured patients.
Hyperglycemia is also neurotoxic in models of brain injury and should be avoided.

Question 22

At what intracranial pressure (ICP) is treatment frequently recommended? Name some methods used to treat an increased ICP.

Answer 22

Treatment of an elevated ICP is frequently recommended when the pressure exceeds 20 mm Hg for a sustained period of time.
There are several methods by which
elevations in ICP can be treated. These include positioning of the head up and neutral, hyperosmolar therapy, osmotic and loop diuretics, cerebrospinal fluid drainage, and the administration of drugs such as barbiturates that decrease both
cerebral blood flow and cerebral metabolism

Question 23

What osmotic diuretic is commonly used to decrease an elevated ICP?

Answer 23

Mannitol is the osmotic diuretic that is most frequently administered to decrease
ICP. Osmotic diuretics decrease ICP by drawing water out of tissues and into the
intravascular space. Osmotic diuretics do so by transiently increasing the osmolarity
of plasma. The dose of mannitol that is administered is 0.25 to 1.4 g/kg over 15 to 30 minutes.
Hypertonic saline 3% 30ml bolus over 10min, it has a reflection coefficient of 1.0 vs 0.9 mannitol therefore is less likely to cross the blood brain barrier. side effects include circulatory overload pulmonary oedema & NAGMA

Question 24

Why should glucose-containing intravenous solutions be avoided in patients with
traumatic brain injury?

Answer 24

Glucose-containing intravenous solutions should be avoided in traumatic brain
injury patients because of the potential for hyperglycemia and hypotonicity, both of
which can be neurotoxic

Question 25

Should corticosteroids be administered to a patient with traumatic brain injury and
signs of an elevated ICP?

Answer 25

Though corticosteroids are often administered to patients with an elevated ICP, they
are most effective in decreasing focal cerebral edema such as that which
develops after brain tumor resection. Steroids have no demonstrated benefit in
traumatic brain injury patients, increase the risk of hyperglycemia, and should not
be given routinely to TBI patients

Question 26

When should hyperventilation be performed to decrease ICP? What is the danger of
excessive hyperventilation?

Answer 26

Deliberate hyperventilation should only be instituted if there is ongoing or
imminent brain herniation and rescue measures are needed prior to
decompressive craniectomy. Prolonged hyperventilation (PaCO2 25 to 30 mm Hg) is
associated with worse outcomes in TBI patients. Excessive hyperventilation in
adults (<25 mm Hg) and children (<20 mm Hg) creates even greater
potential for cerebral ischemia, as cerebral blood flow decreases in response to
alkalosis.

Question 27

When does a trauma patient require cervical spine stabilization at the time of initial
assessment? How do trauma providers “clear” a patient’s cervical spine?

Answer 27

All trauma patients with a loss of consciousness, an unclear history, or a mechanism
of injury suggestive of neck injury should be placed in a rigid cervical spine collar at
the time of initial assessment, if not already done. Mechanisms of injury with a
higher likelihood of cervical spine injury include: front-end motor vehicle accident
without a seat belt, head-first fall, and blunt maxillofacial trauma. “Clearing” the
cervical spine (i.e., declaring that cervical spine stabilization is no longer
necessary) occurs when a patient reliably denies pain with neck palpation and neck
movement. This should not be done if the patient has a distracting injury or
altered mental status. If physical examination is unreliable, computed tomography
and MRI are commonly used to diagnose cervical spine fractures and ligamentous
injuries.

Question 28

How is the “E” of the “ABCDEs” addressed in the initial evaluation of a trauma
patient?

Answer 28

The final component of the “ABCDEs” of trauma assessment is Exposure/
Environment. This begins with the removal of all clothing and prehospital dressings,
a practice that allows for a complete examination of the entire body to ensure that
no injuries are missed. Contaminated and cold clothing are also removed at the same
time, transitioning to a safer and warmer environment for the patient. Once
examined, a hypothermic patient should be rewarmed with blankets, forced
air blankets, and warmed intravenous fluids.

Question 29

How does the initial evaluation of a burn injury patient differ from other trauma
patients?

Answer 29

Special considerations for a burn injured patient include the administration of
100% oxygen regardless of airway examination due to risk of carbon monoxide
poisoning, calculation of total body surface area burned, and assessment for signs
of inhalational injury (e.g., singed nasal hair, voice changes, carbonaceous
sputum).

Question 30

What are some indications for endotracheal intubation in the trauma patient with a
burn injury? What is the danger of delaying endotracheal intubation in a patient
with suspected inhalational injury?

Answer 30

For the burn injury patient arriving to a trauma center, a history of closed space
fire or explosion, and the presence of facial burns, singed nasal hair or
eyebrows, and/or carbonaceous sputum are all risk factors for significant
inhalational injury and need for endotracheal intubation. Stridor, hoarseness, or
visualized periglottic swelling/soot are signs of imminent loss of airway and
indications for immediate endotracheal intubation. Patients with inhalational
injury can rapidly develop facial and glottic edema that completely obstructs the
airway, making oral intubation of the trachea difficult or impossible

Question 31

How is the percentage of body surface area burned estimated in an adult?

Answer 31

patient’s percentage of body surface area (BSA) burned is estimated using the
“rule of nines”

Question 32

Why should burn patients be initially placed on 100% oxygen, regardless of pulse
oximetry reading?

Answer 32

Burn injury victims may have suffered from smoke inhalation injury with
associated carbon monoxide inhalation, particularly if the patient had been exposed
to smoke in a closed space. Carbon monoxide has a binding affinity for hemoglobin
that is about 200 times greater than that of oxygen. The presence of high carbon
monoxide levels therefore creates a functional anemia by reducing the oxygen
content and delivery of a patient’s hemoglobin, despite the presence of a normal
PaO2. In addition, the binding of carbon monoxide to hemoglobin shifts the
oxyhemoglobin dissociation curve to the right, making the remaining oxygen bind
more tightly to hemoglobin and decreasing the ability of hemoglobin to unload
oxygen at the tissues. A pulse oximeter will have normal readings despite carbon
monoxide toxicity. Carbon monoxide toxicity should be treated with the
administration of 100% oxygen. A high PaO2 will lead to the removal of carbon
monoxide from hemoglobin with greater rapidity

Question 33

Why do burn patients require larger than typical amounts of fluid resuscitation?

Answer 33

The burn injury patient often requires large volumes of fluid for volume
resuscitation after his or her injury secondary to huge volume shifts into burned
tissue, increased vascular permeability, evaporative losses, and increased
metabolism. The Consensus formula (traditionally known as the Parkland formula)
is used to calculate the initial rate of fluid administration. Lactated Ringer
solution should be given at 4 mL/kg in the first 24 hours for every 1% of the patient’s
body surface area that is burned, with one half of the calculated volume
administered in the first 8 hours after injury. The remaining half should be
administered in the subsequent 16 hours, though the fluid rate should be
continually adjusted to maintain adequate organ perfusion.

Question 34

What type of fluid should be used to resuscitate burn patients? Why do burn patients
often receive a different volume over the first 24 hours than that initially
calculated?

Answer 34

Warmed isotonic solution such as lactated Ringer solution should be used for fluid
resuscitation in burn patients. Colloids have no demonstrated advantage over
crystalloid and may actually worsen outcomes. While the Consensus formula is used
to determine the initial fluid requirements of burn patients, the fluid rate is typically
adjusted continuously, based on a urine output goal of 0.5 mL/kg/hr, to avoid
overresuscitation or underresuscitation of patients.

Question 35

How should providers evaluate a patient with a suspected closed-head injury?

Answer 35

Patients suspected of having a closed-head injury can be evaluated by history,
physical examination, and radiologic studies. The hallmark clinical sign of a closed-
head injury is loss of consciousness. A GCS score should be calculated based on eye
opening and verbal and motor responses. A noncontrast computed tomographic
scan of the head should be performed as early as possible to assess for intracranial
hypertension or a need for emergent operative intervention. Midline shift, brain
herniation, skull fractures, and any intracranial bleeding can be quickly assessed
with computed tomography.

Question 36

What is a plateau wave in the ICP wave tracing?

Answer 36

A plateau wave in the ICP wave tracing refers to an abrupt increase in the ICP
observed during continuous monitoring. This can occur following painful
stimuli even in an otherwise unresponsive patient. The plateau wave is usually
sustained for 10 to 20 minutes, followed by a rapid decrease in the ICP. The presence
of plateau waves on an ICP wave tracing may indicate that the intracranial
compliance is low. Some providers administer opioids and/or lidocaine to blunt this
effect, though the efficacy of such measures is unclear

Question 37

How does the time since a patient’s last meal affect the initial airway management of
a trauma patient?

Answer 37

In general, rapid sequence intubation of the trachea should be performed for all
emergency trauma procedures, so the time since a patient’s last meal has no impact
on airway management. Because gastrointestinal motility decreases following
trauma, providers assume that all trauma patients have full stomachs and are at risk
for the aspiration of gastric contents. Rapid sequence intubation of the trachea
reduces this risk by minimizing the time between loss of airway reflexes and
placement of a secure airway

Question 38

How does the maintenance of general anesthesia differ in emergency trauma
surgery compared to elective outpatient surgery?

Answer 38

In emergency surgery for trauma, the risks of preexisting hypovolemia, massive
hemorrhage, and hemodynamic instability are higher; therefore general anesthesia
is maintained with lower than usual doses of inhaled volatile anesthetics or
benzodiazepines to optimize hemodynamic stability. Ketamine can also be used for
this purpose. Nitrous oxide is generally avoided in patients with a potential for
pneumothorax or for abdominal procedures

Question 39

How can movement during surgery be prevented if a trauma patient is too unstable
to tolerate high levels of general anesthetic agents?

Answer 39

If a trauma patient is unable to tolerate high levels of general anesthetics,
neuromuscular blocking drugs are needed to prevent skeletal muscle movement
and facilitate the surgical procedure. Small doses of a benzodiazepine or
scopolamine can be used under these circumstances in an attempt to prevent recall.
Under these critical conditions, patients may experience some recall of the
intraoperative events, making it important for the anesthesiologist to
communicate with the patient during and after the procedure

Question 40

What are the basic principles of intraoperative fluid management for trauma
patients needing emergency surgery?

Answer 40

Intraoperative fluid management for trauma patients follows the same principles
as the initial management of the acute trauma patient, with the goals of
maintaining adequate circulating volume while optimizing conditions for
hemorrhage control. Fluid resuscitation may be initiated with isotonic crystalloid
solutions, with early transition to blood products and permissive hypotension if
hemorrhaging is uncontrolled. Hypothermia, coagulopathy, and severe acidosis
should be actively prevented and corrected. Rapid fluid infusion, fluid warmers,
and autotransfusion systems should be used if appropriate and available

Question 41

What diagnostic tests are used to guide intraoperative fluid therapy?

Answer 41

Arterial blood gases, hematocrit and platelet count, coagulation tests, and
electrolytes are followed regularly to assess the progress of resuscitation and surgery. Invasive monitoring, such as arterial pressure variability, central venous pressure, and echocardiography, is also commonly used to guide therapy.
Use of newer technologies such as thromboelastography and central venous oxygen saturation can also provide real-time measurements of coagulopathy and shock, respectively.

Question 42

What preparations are needed prior to surgical opening of the peritoneum in an
exploratory laparotomy for abdominal injuries?

Answer 42

Arterial blood gases, hematocrit and platelet count, coagulation tests, and
electrolytes are followed regularly to assess the progress of resuscitation and
surgery. Invasive monitoring, such as arterial pressure variability, central venous
pressure, and echocardiography, is also commonly used to guide therapy.
Use of newer technologies such as thromboelastography and central venous
oxygen saturation can also provide real-time measurements of coagulopathy
and shock, respectively

Question 43

What injuries might result from trauma to the abdomen? How is the diagnosis of
intraabdominal hemorrhage made in a trauma patient?

Answer 43

Injuries that may be sustained in abdominal trauma include soft tissue
contusions or avulsions, rupture of visceral organs, or laceration of the spleen or
liver. Injury to the spleen or liver can result in significant hemorrhage. The diagnosis
of intraabdominal hemorrhage is made by FAST (focused assessment with
sonography in trauma) examination, peritoneal lavage, and/or computed
tomography.

Question 44

What is “damage control” surgery and how does it benefit trauma patients?

Answer 44

“Damage control” surgery for trauma patients refers to the practice of focusing the
initial surgical intervention on hemorrhage control and abbreviated surgery, with a
plan to delay extensive examination and definitive repair of all injuries until after
the patient is fully resuscitated and stabilized in the ICU. This practice allows for
shorter operating and general anesthesia time initially, achieves hemorrhage
control and shock reversal sooner, and reduces the risk of developing acidosis,
coagulopathy, and hypothermia.

Question 45

What is the treatment for a hypotensive motorcycle accident victim with pelvic
instability on examination and presumed pelvic bleeding?

Answer 45

After establishing that the airway and breathing are stable, the pelvic ring should be
initially closed with a pelvic binder device, followed by angioembolization of pelvic
vessels in the interventional radiology suite. If interventional radiology services are
not available, extraperitoneal packing can be performed to achieve hemorrhage
control, with external fixation of the pelvis performed once the patient is fully
resuscitated and hemodynamically stable.

Question 46

What is the definition of abdominal compartment syndrome?

Answer 46

Abdominal compartment syndrome is defined as an intra abdominal pressure
greater than 20 mm Hg with associated organ dysfunction. Trauma patients with
abdominal injury and/or large volume resuscitation should be closely monitored for
abdominal compartment syndrome

Question 47

What types of mass casualty disasters are possible? What are intentional disasters?

Answer 47

Mass casualty disasters are events that require more resources than the local
community can provide. Disasters can be natural (e.g., floods and earthquakes),
unintentional (e.g., industrial or multivehicle accidents), or intentional. Intentional
disasters are acts of terrorism or warfare, and can be explosive, nuclear,
biologic, or chemical disasters.

Question 48

How long should hospitals be prepared to manage mass casualty disasters before
state and national resources arrive?

Answer 48

Additional resources are unlikely to arrive for at least 24 to 72 hours after a disaster,
so hospitals should have enough resources within the local community to respond
for this period of time. Community emergency preparedness plans should be in
place and coordinated among local health care providers, law enforcement
agencies, fire and rescue services, and local governments

Question 49

What roles do anesthesia providers play during mass casualty events?

Answer 49

In the event of a mass casualty disaster, anesthesia providers may be required to
fulfill many roles including assistance with triage, stabilization of patients in the
emergency department, resuscitation and life support in the intensive care unit,
as well as intraoperative patient management. Like all clinicians, anesthesia
providers should also be able to fulfill their duties within the local emergency
response plan, recognize and report any suspected cases of mass casualty events,
and be familiar with available exposure prophylaxis.

Question 50

What are the goals of mass casualty triage? How are patients classified? What is an
“expectant” mass casualty patient?

Answer 50

The goals of patient triage in mass casualty events are to quickly prioritize
injuries based on severity of injury and likelihood to survive, so that limited
resources can be used to achieve the greatest population benefit. This concept of population-based resource allocation can be difficult for providers used to utilizing
every possible resource for each patient under their care. While multiple mass
casualty triage systems exist, nearly all divide patients into groups requiring
immediate, delayed, minimal, or no treatment. “Expectant” patients are those who
are expected to die of their injuries, even if life-saving surgery were attempted.
Expectant patients are separated from the main patient flow and placed in a quiet
area with an emphasis on analgesia and comfort

Question 51

Where does decontamination of mass casualty patients occur?

Answer 51

Decontamination of mass casualty patients is typically performed at the scene
before transportation. Hospitals set up a secure area outside of the main hospital
area to complete decontamination and triage of patients. Out-of-hospital
decontamination reduces ongoing exposure injuries and minimizes the risk of
secondary exposure to health care providers and other patients

Question 52

What are the advantages of ketamine, when compared to other anesthetic agents, in
facilitating surgical procedures during mass casualty scenarios?

Answer 52

Mass casualty events create situations where patients outnumber resources,
including airway equipment and ventilators. Maintaining spontaneous ventilation
and hemodynamic stability can therefore be critical in such patients. Ketamine is a
useful and commonly used anesthetic agent in such scenarios—including
prehospital procedures such as limb amputation—because it provides analgesia
and hypnosis with minimal depression of respiratory or cardiovascular
function.

Question 53

What are the risks of neuraxial blockade in mass casualty patients?

Answer 53

Neuraxial blockade (i.e., epidural or spinal anesthesia) is generally avoided in mass
casualty patients due to the risk of severe hypotension due to hypovolemia and
underlying injury. Coagulopathy and need for immobilization are also common
reasons to avoid neuraxial blockade for emergency trauma surgery

Question 54

How does the initial assessment of a trauma patient differ if the injuries occurred
during a nuclear power plant explosion?

Answer 54

Transmission of radioactive material from victim to health care provider is low, so
standard trauma protocols should be followed during the initial evaluation of a
nuclear exposed trauma patient, progressing from “A” through “D”: airway,
breathing, circulation, disability (neurologic status). Decontamination is then
performed as part of the assessment and treatment of “E,” or exposure.

Question 55

How are nuclear disaster patients decontaminated?

Answer 55

As part of the exposure assessment, nuclear disaster victims are externally
decontaminated by removing all clothing and rinsing the skin with warm soapy
water. Once stabilized and externally decontaminated, internal decontamination is
performed with methods such as gastric lavage, emetics, laxatives, and diuretics, as
well as copious irrigation of any open wounds. These measures are necessary to
prevent continued injury from retained nuclear material.

Question 56

What are the typical findings in acute radiation syndrome and what can be done to
prevent it?

Answer 56

Acute radiation syndrome is characterized by thrombocytopenia, granulocytopenia,
nausea, and vomiting. Once stabilized, the patient should be monitored
continuously for such signs. Prevention involves minimizing the duration of
exposure through both external and internal decontamination. Medications can
be given to facilitate renal excretion and chelation. Potassium iodide can also be
given within the first 24 hours to prevent radiation-induced thyroid
abnormalities

Question 57

What are “category A” agents, with respect to bioterrorism?

Answer 57

Category A bioterrorism agents, as classified by the United States Centers for Disease
Control and Prevention, are agents thought to be mass-engineered by terrorist
groups, easily disseminated or transmitted to victims, have a high mortality rate,
and/or create public panic if released. Examples of category A agents are anthrax,
smallpox, and Ebola virus.

Question 58

The appearance of five young patients in the emergency department with low-grade
fever and myalgias for several days, who all now present with severe substernal
chest pain and severe hypoxemia, should raise suspicions of exposure to what
bioterrorism agent? What finding on chest radiograph would support this
diagnosis? What else should be done for these patients and exposed individuals?

Answer 58

Any clustering of unusual illness should be treated as victims of bioterrorism until
proven otherwise. In this case, the history of flulike symptoms followed by chest
pain and profound respiratory distress suggests inhalational anthrax. Shock an adenopathy, can be seen on chest radiograph of inhalational anthrax patients. When
profound dyspnea develops, death can ensue within 2 days; therefore treatment and
supportive measures should be instituted immediately (e.g., antibiotic therapy,
endotracheal intubation, and mechanical ventilation). Either ciprofloxacin or
doxycycline can be used to effectively treat weaponized anthrax. Although
inhalational anthrax presents little to no risk of secondary spread from patients with
established infection, such patients should initially be isolated and health care
officials should be notified. Prophylaxis for exposed individuals can be done with
either a fluoroquinolone alone for 60 days or a vaccination plus a fluoroquinolone
for 30 days

Question 59

How do the cutaneous manifestations of smallpox and varicella zoster differ?

Answer 59

Smallpox produces cutaneous lesions 72 to 96 hours after a fever, whereas
patients with varicella zoster infection, or “chickenpox,” develop their rash at the
same time as a fever. In addition, smallpox lesions appear all at once and will
therefore all be at the same stage. In contrast, chickenpox lesions appear at different
times, so physical examination reveals lesions with different stages of lesion
development (papules, vesicles, pustules, scabs)

Question 60

How long is aerosolized plague viable if released in weaponized form? How is a
patient with pneumonic plague managed?

Answer 60

Aerosolized plague (Yersinia pestis) is viable for approximately 60 minutes. If an
individual develops pneumonic plague, management includes strict isolation and
exposure precautions because pneumonic plague is highly contagious. Early
antibiotic treatment is also critical, as the mortality of untreated individuals
approaches 100%. Streptomycin, gentamicin, tetracycline, and chloramphenicol are
all effective therapies for plague.

Question 61

A group of travelers were exposed to an unknown vapor during a terrorist attack.
Twelve hours later, several of those exposed experience difficulty breathing and
progressive weakness, with decreased salivation and urinary retention. What
category A bioterrorism agent is the most likely cause of these symptoms? What
treatment is available, and what precautions should a care provider take? How
would the presumed agent differ if those exposed had increased salivation and
urinary incontinence?

Answer 61

Clostridium botulinum toxin is a category A agent that causes skeletal muscle
weakness between 12 to 36 hours after ingestion or inhalation of the toxin. Botulism
results from inhibition of acetylcholine release, and can be treated with trivalent
antitoxin. Endotracheal intubation and mechanical ventilation may also be
required. The toxin is not contagious, however, therefore health care providers do
not need to follow any additional special precautions. While botulism leads to
decreased salivation, ileus, and urinary retention, nerve agents (e.g., sarin) are
acetylcholinesterase inhibitors and cause cholinergic effects in addition to skeletal
muscle weakness

Question 62

What is a nerve agent?

Answer 62

Nerve agents are military-grade chemicals that act, similar to organophosphate
pesticides, by inhibiting acetylcholinesterase and produce cholinergic effects
including muscle fasciculations, weakness, incontinence, and hypersecretion.
They are typically lipophilic clear liquids that vaporize at room temperature and
are absorbed through the skin, mucous membranes, lungs, or gastrointestinal
tract.

Question 63

What is the treatment for Sarin-exposed individuals? How does pretreatment with
pyridostigmine provide protection from nerve gas exposure?

Answer 63

Sarin is a potent nerve agent that has been used recently in chemical terrorist
attacks. It is also referred to by the two-letter NATO military code “GB.” Like
other nerve agents, exposure to sarin should be treated with atropine (2 to 6 mg IM)
and pralidoxime (600 to 1800 mg IM), with atropine redosed every 5 to 10 minutes
until secretions begin to decrease. Pyridostigmine is a medication that reversibly
binds to AChE. Administration of pyridostigmine 30 minutes before exposure
therefore provides protection by occupying the binding sites that the nerve
agents target. It then dissociates from the AChE enzyme after the exposure
risk has passed.