1. Nasotracheal intubation:
A. Is preferred for the unconscious patient without cervical spine injury.
B. Is preferred for patients with suspected cervical spine injury.
C. Maximizes neck manipulation.
D. Is contraindicated in the patient who is breathing spontaneously.
Answer: B
DISCUSSION: The first principle in the management of any injured patient is to secure an adequate airway. This can be particularly difficult in the presence of facial or laryngeal trauma, or in the unconscious patient with a suspected cervical spine injury. The mechanical removal of oral debris followed by the “chin lift” or “jaw thrust” maneuvers to relieve soft tissue obstruction of the pharynx are the first steps. However, when there is any question regarding the adequacy of the airway, or in the presence of severe head injury, or when the patient is in profound shock, more definitive airway control is required. In most patients this involves oral endotracheal intubation. However, the insertion of an oral endotracheal tube often involves hyperextension of the neck with the potential for aggravating cervical spine ligamentous or bony injury. Nasotracheal intubation is the preferred option for the patient with suspected cervical spine ligamentous or bony injury since the head and neck can be maintained in the neutral position with minimal manipulation. This technique requires a breathing patient, as the passage of air must be heard through the nasotracheal tube prior to its insertion through the larynx into the trachea. Nasotracheal intubation is contraindicated in the presence of mid-face fractures. In this situation, a surgical airway (cricothyroidotomy, tracheostomy, or needle cricothyroidotomy) is the preferred option.
2. Cardiac contusions caused by blunt chest trauma:
A. Are fairly easy to diagnose.
B. Occur in up to 20% to 40% of patients with major blunt thoracic trauma.
C. Do not usually cause right ventricular dysfunction.
D. Demonstrate arrhythmia as the most common complication.
Answer: BD
DISCUSSION: Cardiac contusions are often difficult to diagnose, but have been estimated to occur in 5% of major trauma patients, and up to 20% to 40% of patients with severe blunt chest injury. The difficulty in diagnosing cardiac contusions is that they remain a pathologic diagnosis, confirmed only at autopsy or on direct cardiac examination. The injury may vary from superficial epicardial petechiae to complete transmural damage. Although significant myocardial injuries, such as ventricular rupture, coronary vessel thrombosis, and valvular disruption, have been reported, the most common clinically significant result of cardiac contusion is the occurrence of arrhythmias. Hence, an initial electrocardiogram (ECG) and subsequent continuous cardiac monitoring for at least 24 hours is generally recommended. Alternative methods of diagnosing myocardial contusion include creatine phosphokinase cardiac isoenzymes (CPK-MB), two-dimensional echocardiography, gated ventricular scintigraphic angiography (GVA), radioactive thallous chloride ( 201Tl) uptake, and right ventricular monitoring. Unfortunately, none of these tests is adequately sensitive or specific in the diagnosis of cardiac contusion, and their correlation with the presence of arrhythmias or ECG changes is also imprecise.
3. According to the recommendations of the American College of Surgeons Committee on Trauma, which of the following patients should be transported to a trauma center?
A. Fifty-year-old female who fell 8 feet from a step ladder, with isolated hip fracture and normal vital signs.
B. Fifteen-year-old bicyclist with closed head injury and Glasgow Coma Scale score of 12.
C. Twenty-three-year-old male assault victim with stab wound to the back, normal vital signs, and respiratory distress.
D. Three-year-old infant passenger (restrained) in motor vehicle accident with normal vital signs and no apparent injuries except abdominal wall contusion.
Answer: BCD
DISCUSSION: The American College of Surgeons Committee on Trauma has developed a field triage decision scheme to help identify trauma victims with a significant risk of dying as a result of their injuries. This classification is based on four factors: (1) abnormal physiologic signs, (2) anatomic area of injury, (3) mechanism of injury, and (4) concurrent or co-morbid disease states. Major physiologic abnormalities include a Glasgow Coma Scale score of less than 13, systolic blood pressure less than 90 mm. Hg, respiratory rate less than 10 or greater than 29 per minute, or a Revised Trauma Score of less than 11 or a Pediatric Trauma Score of less than 9. Significant anatomic considerations include penetrating injuries to the torso, head and neck, and proximal extremities, flail chest, combination of trauma with burns to greater than 10% of body surface area, two or more proximal long bone fractures, pelvic fractures, paralysis, or traumatic amputation above the wrist or ankle. Significant mechanisms of injury include a death in the same passenger compartment or ejection from the automobile, high-impact (greater than 5 miles per hour) auto-pedestrian injuries, or a pedestrian thrown or run over. The co-morbid factors include pediatric or elderly (<5 or >55) patients or known history of insulin-dependent diabetes or cardiac, respiratory, or psychotic disorders. These criteria should serve as guidelines for medical control and the pre-hospital care providers. Such triage guidelines have been shown to produce the triage of only a small fraction (5% to 10%) of all injured patients to Level I or Level II trauma centers.
4. Which of the following statements about head injuries is/are false?
A. The majority of deaths from auto accidents are due to head injuries.
B. Head injury alone often produces shock.
C. A rapid and complete neurologic examination is part of the initial evaluation of the trauma patient.
D. Optimizing arterial oxygenation is part of initial therapy.
Answer: B
DISCUSSION: Head injuries cause the majority of deaths following automobile accidents, with rupture of the thoracic aorta the second most common cause of fatality. Head injury itself rarely produces hypotensive shock. It is only in the terminal phases of brain death that hypotension may be attributable to head injury alone. Therefore, hypotension in trauma patients must be assumed to be secondary to volume depletion or ongoing hemorrhage. An occult site of hemorrhage (chest, abdomen, pelvis, retroperitoneum, or extremities) must be strongly suspected and dealt with accordingly. A rapid and complete neurologic assessment is a crucial part of the initial assessment of all trauma patients. This initial exam gives an excellent indication of injury severity and prognosis. Since the ultimate outcome of a brain injury is dependent on adequate cerebral perfusion and oxygenation, adequate airway control, ventilation, hemorrhage control, volume restitution, and arterial oxygenation are crucial factors in the early management of head injuries.
5. Which of the following statements about maxillofacial trauma is/are false?
A. Asphyxia due to upper airway obstruction is the major cause of death from facial injuries.
B. The mandible is the most common site of facial fracture.
C. The Le Fort II fracture includes a horizontal fracture of the maxilla along with nasal bone fracture.
D. Loss of upward gaze may indicate either an orbital floor or orbital roof fracture.
Answer: B
DISCUSSION: Maxillofacial injuries generally do not cause life-threatening injuries, with the exception of those that occlude the airway. Therefore, the first priority in assessing and managing the patient with maxillofacial trauma is to assess and assure the adequacy of the airway. The face is typically divided into thirds when defining injuries. Injuries to the upper third of the face are often accompanied by ocular or central nervous system complications as well as facial deformities. Fractures of the orbital roof are frequently associated with frontal sinus and nasal ethmoid fractures, and are accompanied by a loss of upward gaze due to involvement of the superior rectus muscle. However, the most common cause of loss of upward gaze is orbital floor injury and associated entrapment of the globe or injury to the inferior rectus muscle. Middle third of facial structures include the maxilla, zygoma, orbits, and nose. The Le Fort classifications of facial fractures are commonly employed to describe these complex fracture lines. In a Le Fort II fracture, the superior fracture line is transverse through the nasal bones or through the articulation of the maxillary and nasal bones with the frontal bones. This is also known as the “pyramidal” fracture of the mid-face. The diagnosis is established by digital manipulation of the anterior maxilla and observation for mobility of the central triangle (the maxilla and nose). The lower third of the face contains a single facial bone, the mandible. After the nasal bones, the mandible is the second most commonly fractured facial bone.
6. What percentage of patients with thoracic trauma require thoracotomy?
A. 10%–15%.
B. 20%–25%.
C. 30%–40%.
D. 45%–50%.
Answer: A
DISCUSSION: Twenty-five per cent of civilian trauma deaths are caused by thoracic trauma, and two thirds of these deaths occur after the patient reaches the hospital. Mortality of hospitalized patients with isolated chest injury ranges from 4% to 8% and increases to 35% when multiple additional organ systems are involved. Despite high mortality, only 10% to 15% of thoracic injuries require thoracotomy. Most injuries are successfully managed by the rather simple life-saving maneuvers of airway control and tube thoracotomy. Unrelenting hemorrhage following either penetrating or blunt thoracic trauma is a primary indication for immediate thoracotomy. An initial thoracic blood loss of greater than 1500 ml. (30% of blood volume) or an ongoing loss of 250 ml. for 3 consecutive hours serves only as a practical guideline. The patient's hemodynamic status and overall condition should be the most influential factors.
7. The radiographic findings indicating a torn thoracic aorta include:
A. Widened mediastinum.
B. Presence of an apical “pleural cap.”
C. First rib fractures.
D. Tracheal deviation to the right.
E. Left hemothorax.
Answer: ABCDE
DISCUSSION: All of the listed radiographic findings should arouse suspicion of a possible torn thoracic aorta. The most common abnormality noted is a widening of the mediastinal shadow, although only 20% to 40% of patients with a wide mediastinum have aortic injury. In addition to the radiographic signs listed, other findings that may alert the physician to the possibility of an aortic tear include loss of aortic contour, elevation of the left mainstem bronchus, depression of the right mainstem bronchus, shift of the nasogastric tube to the left, and the presence of retrocardiac density. Aortography remains the “gold standard” diagnostic modality and is indicated if aortic injury is suspected on the basis of mechanism of injury and any of these suggested findings.
8. Which of the following statements about diagnostic peritoneal lavage (DPL) is/are false?
A. DPL is the diagnostic procedure of choice for gunshot wounds to the abdomen with no obvious intra-abdominal injuries.
B. The average reported incidence of false-positive DPL in patients with significant pelvic fractures is 20% to 30%.
C. Accuracy rates for DPL have generally been reported between 95% and 97%.
D. DPL has been entirely replaced by computed tomography as the diagnostic procedure of choice following blunt abdominal trauma.
Answer: AD
DISCUSSION: DPL remains the most sensitive and specific indicator of intra-abdominal injury in the trauma patient. The accuracy rates for DPL in several large collective series reveal an overall sensitivity of 95%, specificity of 98% to 99%, and overall accuracy of 97%. As result, DPL remains the mainstay for diagnosis of intraperitoneal injury in the trauma patient; however, not every trauma patient requires DPL. In the awake, alert, and responsive patient with isolated abdominal injuries, the physical examination and history are very helpful in predicting the presence of significant injury. In the patient with lower torso (nipples to pubis) or back or flank gunshot wounds, the incidence of intra-abdominal injury is so high that exploratory laparotomy without further diagnostic modalities is generally advocated. In addition, DPL is generally inaccurate in the diagnosis of retroperitoneal injuries (duodenum, renal, pancreas), and significant retroperitoneal hemorrhage in association with pelvic fractures produces a false-positive DPL rate of up to 30%. Computed tomography (CT) scans have proved extremely valuable in these situations. General recommendations for the use of abdominal CT scans in trauma victims include patients who are hemodynamically stable (normal) with (1) equivocal abdominal examination, (2) closed head injury, (3) spinal cord injury, (4) hematuria, and (5) pelvic fractures with significant bleeding. These five indications are appropriate if the patient is truly hemodynamically stable and the time required to perform CT does not delay any surgical procedures.
9. A 28-year-old male was injured in a motorcycle accident in which he was not wearing a helmet. On admission to the emergency room he was in severe respiratory distress and hypotensive (blood pressure 80/40 mm. Hg), and appeared cyanotic. He was bleeding profusely from the nose and had an obviously open femur fracture with exposed bone. Breath sounds were decreased on the right side of the chest. The initial management priority should be:
A. Control of hemorrhage with anterior and posterior nasal packing.
B. Tube thoracostomy in the right hemithorax.
C. Endotracheal intubation with in-line cervical traction.
D. Obtain intravenous access and begin emergency type O blood transfusions.
E. Obtain cross-table cervical spine film and chest film.
Answer: C
DISCUSSION: Airway remains the first priority in the management of any patient with multiple injuries. Control of the airway in a patient with head, face, and neck injury can be extremely challenging. In the patient presented, the best option given for control of the airway is endotracheal intubation with in-line cervical traction. This requires at least two persons, one to maintain the head in the neutral position and one to insert the endotracheal tube under direct vision. An alternative in this case would be emergency cricothyroidotomy, tracheostomy, or needle-jet insufflation. Nasotracheal intubation is not an option in the presence of a mid-face fracture and a nasal hemorrhage. Clearly, attention must also be directed at assuring adequacy of ventilation (potential right pneumothorax), assessing and treating obvious hemorrhage, determining if there is occult intra-abdominal or thoracic hemorrhage, and determining the patient's neurologic status. While management of these other issues can occur simultaneously, they do not take priority over securing an adequate airway. In this patient the airway is so tenuous that time should not be spent obtaining a cross-table cervical spine film and chest film prior to definitive control of the airway.
10. True or False?
A. Trauma is second only to congenital heart disease as the leading cause of death in children.
B. Each year in the United States, approximately 50,000 people die from injuries.
C. Motor vehicle accidents (MVAs) involving intoxicated drivers are responsible for 50% of all MVA fatalities.
D. Active prevention strategies (e.g., seat belts, helmets) have not proved effective in reducing injuries and fatalities.
E. Falls and diving accidents comprise approximately 30% to 40% of cervical spine injuries.
Answer: TRUE C; FALSE ABD
DISCUSSION: The statistics on injuries highlight trauma as “the principal public health problem in America today.” Trauma remains the leading cause of death in children and adults up to the age of 44 years, and injuries kill more Americans age 1 to 34 years than all diseases combined. Each year more than 140,000 Americans die of injuries, 50,000 due to motor vehicle accidents. Just over 50% of motor vehicle injuries involve intoxicated drivers. Injury prevention would be the most cost-effective method of dealing with this major social and economic burden. Active injury prevention strategies are those that require active continued cooperation on the part of the individual, such as wearing a helmet when driving a motorcycle or wearing seat belts in automobiles. Passive approaches such as fitting all motor vehicles with driver air bags require little or no individual cooperation and have clearly proved the more effective option, but active prevention strategies have repeatedly been demonstrated to reduce injury fatalities. States with seat belt and child restraining laws show an increase in seat belt use of more than 60% with a concurrent 9% to 12% reduction in occupant fatalities. Motor vehicle accidents are responsible for approximately 60% of spinal cord injuries, falls for 20% to 30%, and diving accidents for an addition 5% to 10%. Spinal cord injury acute care and rehabilitation represent some of the most expensive medical treatment, with an average hospital charge of $50,000 in 1988 for a quadriplegic survivor.
11. Regarding the diagnosis and treatment of cardiac tamponade, which of the following statements is/are true?
A. Accumulation of greater than 250 ml. of blood in the pericardial sac is necessary to impair cardiac output.
B. Beck's classic triad of signs of cardiac tamponade include distended neck veins, pulsus paradoxicus, and hypotension.
C. Approximately 15% of needle pericardiocenteses give a false-negative result.
D. Cardiopulmonary bypass is required to repair most penetrating cardiac injuries.
Answer: C
DISCUSSION: Cardiac tamponade is most frequently caused by penetrating thoracic injury, but may occasionally be observed following blunt thoracic trauma from cardiac chamber rupture, coronary artery laceration, or ascending dissection of an aortic tear. Accumulation of as little as 150 ml. of blood in the pericardium will sufficiently decrease diastolic filling to produce distended neck veins, cyanosis, and decreased cardiac output. Beck's classic triad of distended neck veins, muffled heart sounds, and hypotension is present in only one third of patients with tamponade. Pulsus paradoxicus is even less frequently discernible. Immediate temporary treatment consists of pericardiocentesis, which also provides a diagnosis. However, approximately 15% of pericardiocenteses give false-negative results because of a clotted hemopericardium. Therefore, echocardiography prior to needle aspiration is generally advisable if promptly available. In the patient in extremis, emergency thoracotomy with pericardiotomy and cardiac repair should be performed. Most patients with penetrating cardiac wounds do not require cardiopulmonary bypass to repair their injuries.
12. Which of the following statements or descriptions typically characterizes the syndrome of overwhelming postsplenectomy sepsis?
A. A syndrome of fulminant gram-negative bacteremia and septicemia in asplenic individuals, characterized by the presence of as many as 10 6 bacterial organisms per cu. mm. circulating in the bloodstream.
B. A syndrome caused primarily by impaired host ability to mount an effective humoral (immunoglobulin) response to infection.
C. A syndrome that occurs in 5% to 7% of patients following traumatic splenectomy.
D. A syndrome of rapidly appearing septic shock unresponsive to antibiotic therapy, with an average mortality of 50%.
E. The syndrome may be prevented by preserving as little as 15% of splenic mass in adult trauma victims.
Answer: D
DISCUSSION: In 1952 King and Schumaker suggested that children who had undergone splenectomy were at risk for the development of bacterial infections, and the syndrome of overwhelming postsplenectomy sepsis (OPSS) was suggested by Diamond in 1969. The syndrome is unlike fulminating bacteremias and septicemia in individuals with normal splenic function. The onset is sudden, with nausea, vomiting, headache, and confusion leading to coma. The new infecting organism is a gram-positive organism in over half the cases, primarily Streptoccoccus pneumoniae. Blood cultures may occasionally demonstrate up to as many as 10 6 bacterial organisms per cu. mm. circulating in the bloodstream. Disseminated intravascular coagulation is common along with hypoglycemia, electrolyte imbalance, and shock unresponsive to antibiotics and fluid or pharmacologic support. Mortality has generally been reported as high as 50% and even up to 80% for pneumococcal infections. The true incidence of overwhelming postsplenectomy sepsis following a splenectomy from trauma is not well defined. Green and colleagues suggested that the risk of OPSS is 166 times the rate expected for the general population. Eraklis and Filler suggested that the incident rate of mortality from sepsis and OPSS is 78 times greater than that expected for the general population. Despite this increased frequency, overwhelming postsplenectomy sepsis remains a rare event. Singer's large review of 688 children who had undergone splenectomy for trauma demonstrated only a 1.45% incidence of postsplenectomy sepsis, but a 40% mortality. The occurrence of OPSS appears to be less following splenectomy for trauma when compared with splenectomy for congenital hematologic disorders. Nonetheless, the recognition of the severe nature of this entity has prompted many trauma surgeons to more aggressively attempt splenic salvage. Animal laboratory evidence suggests that at least 50% of the splenic tissue mass must be preserved to prevent overwhelming postsplenectomy sepsis. The immunologic function of the spleen that appears to be most beneficial in preventing OPSS is the spleen's capacity for clearance of blood-borne particles and the provision of circulating opsins, which assist in cell-mediated immunologic functions.
Trauma deaths most commonly occur at three distinct time periods after injury. Which of the following statement(s) is/are true concerning the time pattern of trauma mortality?
a. Only 10% of trauma deaths occur within seconds or minutes of the injury
b. A second mortality peak occurs within hours of injury with deaths in this time period being markedly reduced with the development of trauma and rapid transport systems
c. Death one day to weeks after the injury are almost entirely due to infection and multiple organ failure
d. Late mortality in trauma patients, occurring days to weeks after the injury, has not been affected by better trauma delivery systems
Answer: b
Trauma deaths occur at three traditionally recognized times after injury. About half of all trauma-related deaths occur within seconds or minutes of injury and are related to lacerations of the aorta, heart, brain stem, brain, and spinal cord. Few of these patients are saved by health care systems, regardless of efficiency. The second mortality peak occurs within hours of injury and accounts for about 30% of deaths, half of which are due to hemorrhage and half due to central nervous system injuries. Important reductions in mortality during this period have resulted from the development of trauma and rapid transport systems. Overall, trauma mortality rates have been reduced from about 30% to 2% to 9% where well-organized trauma care systems exist. The third mortality peak includes deaths that occur one day after trauma to weeks later. This mortality rate is usually attributed to infection and multiple organ failure. Ten to 20% of trauma deaths occur during this period. The development of efficient trauma systems, however, has changed the epidemiology of these deaths. During the first week after trauma, refractory intracranial hypertension after severe head injury now accounts for a significant number of these deaths. The incidence of sepsis and multiple organ failure has diminished as the result of aggressive and better early resuscitation and care. Sepsis and multiple organ failure now account for about 5% of overall mortality and only 30% of late mortality where organized trauma systems exist.
Which of the following statement(s) is/are true concerning the epidemiology of trauma?
Trauma is the leading cause of death of individuals less than 44 years of age
Trauma follows only cancer and heart disease as leading causes of productive life lost
Motor vehicle accidents are the most common cause of traumatic death in young males of all ethnic groups
Young males are the population at highest risk for trauma death
Answer: a, d
Although injury affects all age groups, it is epidemic within the younger population of our society. In the United States, injury is the leading cause of death in individuals less than 44 years and results in 70% of the total hospital admissions. Young males are the highest risk group, not because of physiologic distinctions, but because of their propensity to engage in high-risk activities. Although the three leading causes of traumatic death in all ethnic groups are motor vehicle accidents, homicide, and suicide, for individuals under 35 years of age, the order in which these occur differs. In the African-American population, the leading cause of death in this age group is homicide, while in all other groups it is motor vehicle accidents. Although morbidity and mortality figures are important, another important method of analyzing the toll injury places on a society is in years of productive life lost. Years of productive life lost is used to reflect the amount of productive working time lost due to premature death. Since injury is so prevalent in the younger population, a traumatic death in this age group will result in a large number of years of productive life lost, more so than deaths in the older age groups due to chronic diseases. In fact, years of productive life lost due to injury are approximately 40% higher than those found in cancer or heart disease patients, the second and third leading causes of productive life lost.
Which of the following statement(s) is/are true concerning the biomechanics of blunt trauma?
A small child and a large adult have a markedly different level of energy transfer in a high speed vehicular collision
Shear strain injuries result from rapid acceleration or deceleration
Tensile strain results from direct compression of tissues
The tolerance of biologic tissue to trauma injury is directly proportional to the elasticity of the organ
Answer: b, c, d
The severity of any injury is directly proportionate to the amount of kinetic energy transferred to the tissues and the properties of that tissue which accept and dissipate the energy. Kinetic energy (KE) is a function of the mass (M) of an object and its
velocity (V):
KE = M x V^2 /2
It is clear from this relationship that changes in velocity alter the kinetic energy transferred more significantly than changes in mass. Therefore, a small child and a large adult, though significantly different in size and weight, are subjected to similar levels of energy transfer in a high-speed vehicular collision, the primary determinant being velocity rather than mass. The tolerance of a biologic tissue to traumatic injury is directly proportional to the elasticity of the organ—that is, its ability to return to its original shape and position. Elasticity is directly affected by the rate of loading, or the rate at which strain is applied to the tissues. Applying the force more rapidly increases the likelihood of exceeding tolerance. Blunt trauma results in two types of forces during impact. First, changes in speed (acceleration or deceleration) create shear strain, and second, deformity changes (stretch or compression) creates tensile strain.
The patient described above has also suffered major facial trauma. Which of the following statement(s) is/are true?
a. A frontal bone fracture and injury to the frontal sinus is a common facial injury in a young adult
b. The optic nerve can be injured in a LeFort type II fracture
c. A facial nerve injury may occur with the fracture of the temporal bone
d. Coronal CT scan images can be a useful adjunct to the evaluation of the patient with facial and head injuries
Answer: c, d
A major cause of maxillofacial trauma are motor vehicle accidents. Facial skeletal fractures and soft tissue damage in the frontal, orbital, nasal, zygomatic, maxillary and mandibular regions are included. The frontal bone, which houses the frontal sinuses, is particularly strong due to its arched configuration as well as thick, hard bone. The amount of force necessary to fracture the frontal sinus is two to three times greater than that necessary for other facial bone fractures. Consistent fracture patterns from blows to the maxilla have been classified by LeFort and occur within and along the maxilla at its junction with weaker and aerated bone of the paranasal sinuses and nasal cavity. The classic LeFort fractures are classified as LeFort I, LeFort II and LeFort III and are of increasing complexity and morbidity. The cribriform plate, ethmoidal arteries, optic nerve and internal maxillary artery are all vulnerable to injury with a LeFort III fracture.
Soft tissue injuries of the face are encountered even more often than facial fractures. The facial nerve is the most important underlying structure at risk since blunt or penetrating trauma to the nerve or branches can cause complete or partial ipsilateral facial paralysis. The most common cause of facial nerve injury is fracture of the temporal bone, but injury can occur anywhere from the intracranial to the extracranial facial course of the nerve.
After securing the airway and controlling life-threatening hemorrhage, the secondary survey including the facial area is carried out. The nose is inspected for deformity, pain, mobility, septal hematoma and obstruction. Bleeding should be managed immediately. Leakage of cerebral spinal fluid suggests a cribriform plate or ethmoidal fracture and a presence should warn against insertion of any nasal tubes or packing. Since CT scan is part of the standard management of the head-injured patient, sections of the facial skeleton can be obtained simultaneously, providing information on the extent of facial fractures in addition to the status of the brain. Axial and coronal sections (obtained with the patient’s head hanging with the neck extended) are complimentary and are especially helpful in delineating the cribriform plate and ethmoid roof region, the orbital rims, and the overall vertical facial height.
There are a number of options for resuscitative fluids. Which of the following statement(s) is/are true concerning fluids used for resuscitation of shock?
a. Resuscitation with crystalloid requires volume replacement in a ratio of 1:1 to volume lost
b. The literature strongly supports the use of colloid as being superior to crystalloid in the resuscitation of shock
c. Risks of autotransfused blood include disseminated intravascular coagulation and activation of fibrinolysis
d. Hypertonic saline solution results in volume expansion, an increase in left ventricular performance, decreased peripheral resistance, and redistribution of cardiac output to kidneys and viscera
e. The use of perfluorocarbons as an experimental resuscitative fluid has been demonstrated to stimulate the immune system
Answer: c, d
Balanced salt solutions are the most commonly used resuscitative fluids, and their use to restore extracellular volume significantly decreases the transfusion requirement after hemorrhagic shock. Lactated Ringers and normal saline are the most effective crystalloid solutions in common use. Resuscitation with crystalloid require a volume administration ratio of 3:1 to 4:1 over volume lost. Although colloids do not replete the interstitial space, they have a volume-expanding effect somewhat greater than the amount used. Colloids commonly used for volume expansion in hypovolemia include albumen, dextran 70, dextran 40, and hydroxyethyl starch (hetastarch). Significant controversy exists concerning the use of crystalloid versus colloid resuscitation. Although the question has not been resolved, several recent studies have indicated an advantage to crystalloid in resuscitation. A meta-analysis of colloid versus crystalloid resuscitation after hemorrhagic shock has demonstrated a higher mortality rate in the colloid resuscitated patients, partly due to pulmonary complications. Patients who lose more than 25 to 30% of total blood volume will need blood for resuscitation. Type O, Rh-negative (universal donor blood) is immediately available without a cross match. Type-specific blood is available within most blood banks within five to ten minutes of receipt of the blood specimen, while the patient is being resuscitated with balanced salt solutions. Although not cross matched, this blood can be administered safely, and therefore its rapid availability and safety make type-specific blood the blood of choice for resuscitation in trauma. Autotransfusion involves the collection of shed blood and its reinfusion through a filter back into the patient. Autotransfused blood may produce disseminated intravascular coagulation (DIC) and activation of fibrinolysis. In addition, blood collected from the peritoneal cavity after hollow viscus injury, even with cell washing, may lead to bacterial contamination of the autotransfused blood. Hypertonic solutions have been used in the resuscitation of patients after burn, shock, elective vascular surgery and trauma. In addition to volume expansion, hypertonic saline solutions have been shown to increase left ventricular performance, decrease peripheral resistance from arteriolar dilatation, and redistribute cardiac output to the kidneys and viscera. Perfluorocarbons are an experimental resuscitation fluid comprised of large, branched or cyclic aliphatic compounds which have the ability to dissolve and carry oxygen. Although effective in volume resuscitation with improved oxygen delivery and oxygen-carrying capacity, perfluorocarbon infusion has been shown to depress platelet counts, plasma immune globulin levels and depress other aspects of immune function.
Hemorrhage initiates a series of compensatory responses. Which of the following statement(s) is/are true concerning the physiologic responses to hemorrhagic shock?
a. An immediate response is an increased sympathetic discharge with resultant reflex tachycardia and vasoconstriction
b. Transcapillary refill is a response serving to restore circulating volume
c. Extracellular fluid becomes increasingly hyperosmolar
d. Adrenergically mediated vasoconstriction is well maintained at the arteriolar and precapillary sphincters
Answer: a, b, c
Hemorrhage initiates both rapid and slower, more sustained compensatory responses. The body responds to maintain hemostasis almost immediately after the onset of hemorrhage. Decreased activation of the arterial baroreceptors, though a decrease in blood pressure or even more subtly, a decrease in pulse pressure, causes an increased sympathetic discharge, resulting in reflex tachycardia and vasoconstriction. Increased adrenergic output with increased secretion of catecholamines also leads to vasoconstriction, increased heart rate, and increased myocardial contractility. Sustained compensatory responses include the release of vasoactive hormones and fluid shifts from the interstitium and the intracellular space. Adrenergically mediated vasoconstriction affects arterial precapillary and postcapillary sphincters and small veins and venules. The decrease in intravascular hydrostatic pressure distal to the precapillary sphincter leads to reabsorption of interstitial fluid into the vascular space and thereby functions to restore circulating volume. This is known as transcapillary refill. The increased release of stress hormones coupled with relative insulin resistance after shock leads to high extracellular glucose concentrations. In addition, products of anaerobic metabolism from hypoperfused cells accumulate in the extracellular compartment, inducing hyperosmolarity. This extracellular hyperosmolarity draws water from the intracellular space, increasing interstitial osmotic pressure, which in turn drives water, sodium and chloride across the capillary endothelium into the vascular space. If the shock state continues, however, the postcapillary sphincter remains in spasm, but the arteriolar and precapillary sphincters cannot maintain the tension, and they become relaxed. As sphincters relax, the capillary hydrostatic pressure increases and sodium, chloride and water move into the interstitium leading to further depletion of intravascular volume.
Which of the following steps is/are part of the primary survey in a trauma patient?
a. Insuring adequate ventilatory support
b. Measurement of blood pressure and pulse
c. Neurologic evaluation with the Glasgow Coma Scale
d. Examination of the cervical spine
Answer: a, b, c
The resuscitation team’s first priority is to simultaneously assess the airway, blood pressure and level of consciousness of the patient. The first priority is assessment of the airway. After establishment of an airway, the next priority is to insure adequate ventilatory exchange by rapid auscultation of both lung fields and assessment for mechanical factors that may interfere with breathing. After establishment of an airway, ventilation and appropriate pleural drainage, if necessary, the next priority is the assessment of the patient’s circulatory status. This includes an estimation of blood volume and cardiac function. The initial survey evaluates blood pressure, pulse, and skin perfusion. It is important to emphasize that effective resuscitation from hemorrhagic shock requires both restoration of intravascular volume and control of hemorrhage. The final priority of the primary survey is a brief neurological evaluation using the components of the Glasgow Coma Scale. Although maintaining axial immobilization of the cervical spine is an important early component of all assessments and resuscitation protocols, examination of the cervical spine regardless of injury is part of the secondary survey.
Immediate life-threatening injuries that preclude air exchange which can be treated in the field include which of the following?
a. Tension pneumothorax
b. Massive open chest wounds
c. Sucking chest wounds
d. Tracheal disruption
Answer: a, b, c
After establishment of a patent and controlled airway, the next priority is to insure that air exchange is taking place. Immediate life-threatening injuries that preclude air exchange include: tension pneumothorax, massive open chest wounds, sucking chest wounds, and tracheal disruption. There are no maneuvers likely to correct tracheal disruption in the field. Both open chest wounds and sucking chest wounds will respond to endotracheal intubation and positive pressure ventilation. Tension pneumothorax may require field decompression in the rare patient. Field techniques to deal with tension pneumothorax include needle thoracostomy and chest tube thoracostomy.
Which of the following statement(s) is/are true concerning the diagnosis of a peripheral vascular injury?
a. The presence of a Doppler signal over an artery in an extremity essentially rules out an arterial injury
b. Doppler examination is a valuable tool in the diagnosis of venous injuries
c. A gunshot wound in the proximity of a major vessel is an absolute indication for arteriography
d. Both the sensitivity and specificity of arteriography of the injured extremity approaches 100%
Answer: d
Segmental arterial pressure determination by Doppler technique is a valuable adjunct to the physical examination of extremity vascular trauma. The presence of audible Doppler signals over an artery in the extremity does not rule out an arterial injury or indicate adequate perfusion. In the healthy and normovolemic person, the normal ankle-brachial index is 1:1. A ratio less than 0.9 or a 20-mm Hg difference between extremities should arouse the suspicion of significant arterial trauma. Doppler examination has not been widely used to screen for significant venous injuries and is of unproven value. The selective use of arteriography is fundamental to the evaluation of patients with suspected vascular trauma. The indications for arteriography generally have included a history of moderate hemorrhage at the penetrating injury site, injury in proximity to major arterial structures, diminished pulses, and peripheral nerve injury in the distribution of a nerve that is in proximity to a major vessel. Proximity as the sole indication for arteriography in the absence of diminished ankle-brachial ratio or other signs of major trauma, has proven to be an unreliable indicator of the need for arteriography. In the absence of classical signs of major vascular injury, patients with penetrating wounds in proximity to major vessels may be observed closely without arteriography. The use of arteriography can significantly reduce the rate of unnecessary exploration for suspected vascular trauma. If routine surgical exploration is performed whenever vascular injury is suspected, a negative exploration rate of about 60% or more can be expected. Selective use of arteriography reduces the negative exploration rate to about 35%. Arteriography is an extremely reliable method of excluding vascular trauma. In this context, the sensitivity is 97% to 100% and the specificity is 90% to 98%, with an overall accuracy between 92% and 98%.
A 22-year-old male is hospitalized with multiple extremity fractures including a comminuted fracture of the femur and multiple rib fractures. Which of the following statement(s) is/are true concerning his hospital course?
a. Low-dose heparin should not be employed during his hospital stay
b. Acute respiratory failure associated with petechiae of the head, torso, and sclerae would suggest a pulmonary embolism
c. Early fracture fixation would decrease the incidence of fat emboli
d. The placement of a Greenfield filter should be avoided due to the risk of lower extremity edema
Answer: c
Perhaps the most catastrophic post-injury complication is pulmonary embolism. All patients with orthopedic injury, particularly those with fractures of the lower extremities or pelvis, are at high risk for deep venous thrombosis and subsequent pulmonary embolism. Prophylaxis with sequential compression devices or low dose heparin has reduced the incidence of deep venous thrombosis in this group. Although concern for the use of heparin is appropriate, prospective studies demonstrate that low-dose heparin therapy can begin safely within 24 hours in 37% of patients and within 48 hours in 75%. Trauma patients who are paralyzed or immobilized by head injury, spine injury, or multiple orthopedic injuries should be considered for placement of a Greenfield filter.
Fat embolism syndrome is a classic triad of acute respiratory failure; altered mental status, and petechiae of the head, torso and sclerae; and is frequently associated with long-bone and pelvic fractures. Less fulminant presentations, without petechiae and with lesser degrees of pulmonary dysfunction, are more common. At present, the only therapy for fat emboli syndrome is supportive care. Therefore, prevention is critical and numerous studies indicate that early fracture fixation decreases the incidence of this and other pulmonary complications. However, a subset of patients with femoral fractures and coexisting lung contusion has been recently found to have a higher incidence of ARDS if the fracture is repaired early than if repaired late.
A middle-aged construction worker had a significant fall on the job and presents with obvious high cervical spine injury. Which of the following statement(s) is/are true concerning his diagnosis and management?
a. A paradoxical breathing pattern in which the abdomen protrudes on inhalation may be observed
b. If the patient appears well compensated on initial evaluation, intubation is unlikely to be necessary
c. The presence of hypotension strongly suggests significant blood loss from associated injury
d. The patient’s extremities are likely to appear warm and well perfused despite the presence of hypotension
e. The use of methylprednisolone beginning 24 hours after the injury will be indicated
Answer: a, d
Fractures to the axial spine, especially in the high cervical spine, can cause varying degrees of respiratory compromise. Patients with ventilatory failure from acute cord injury typically present with a paradoxical breathing pattern in which the abdomen protrudes on inhalation, creating a see-saw appearance. This is caused by paralysis of abdominal musculature and is seen with injuries as low as T-10 to T-11. Early endotracheal intubation and mechanical ventilation must be considered, even in patients who appear compensated on initial evaluation. There is a strong tendency for such patients to tire and develop respiratory failure a few hours after the injury.
In addition to ventilatory compromise, high axial spinal lesions can cause significant hypotension, confusing the initial evaluation of the patient. Most CNS control of arterial tone is mediated through the sympathetic nervous system. In high thoracic and cervical spinal cord injuries, these controlling pathways may be interrupted, with subsequent loss of vasomotor tone. This results in hypotension even without significant blood loss. Unlike hypovolemic shock, the patient’s extremities are warm and well perfused.
A prospective, randomized trial has suggested that high doses of methylprednisolone given within 8 hours of injury have improved neurologic recovery. Starting treatment with steroids more than 8 hours after injury results in worse recovery than the placebo and is not recommended.
Which of the following statement(s) is/are true concerning Emergency Room thoracotomy?
a. Overall survival rates approach 25%
b. Blunt trauma patients without signs of life upon arrival in the Emergency Room are candidates for Emergency Room thoracotomy
c. All patients with penetrating trauma to the chest and the absence of vital signs are candidates for ER thoracotomy
d. None of the above
Answer: d
A recent meta-analysis of 24 reports concerning the outcome of Emergency Room thoracotomy found that the overall survival rate was 11%. There were no survivors among patients with no signs of life (supraventricular electrical activity, pupillary reaction, and agonal respirations) at the scene. In addition, there were no neurologically intact survivors among blunt trauma patients without signs of life upon arrival in the Emergency Department. Considering these findings, an appropriate algorithm would indicate that Emergency Room thoracotomy for penetrating trauma is indicated only if patients had signs of life at the scene and had lost signs of life less than five minutes prior to arrival in the Emergency Room. Blunt trauma patients would be allowed Emergency Room thoracotomy only if the patient had signs of life upon arrival at the Emergency Room. If patients meet these criteria and lose cardiac function, airway placement and fluid resuscitation is initiated simultaneously with or immediately followed by left anterior thoracotomy, pericardiotomy, and internal cardiac massage.
An untreated or an unrecognized compartment syndrome produces nerve and muscle damage and prevents good functional recovery despite the patency of vascular repair. Which of the following factors suggests the need for a fasciotomy?
a. A period of 6 hours or more between injury and restoration of perfusion
b. Combined arterial and venous injuries
c. Postoperative signs of muscle pain or pain on passive stretch
d. Elevated compartment pressures
answer: a, b, c, d
Factors that suggest the need for fasciotomy are as follows:
1. Prolonged period (6 hours or more) between injury and restoration of perfusion
2. Associated crush injury
3. Preoperative calf swelling
4. Combined arterial and venous injuries
5. Extensive venous ligation
6. Postoperative signs or disproportionate muscle pain, pain on passive stretch, or tender and firm muscles
7. Elevated compartment pressures
Which of the following statement(s) is/are true concerning the consequences of vascular injuries?
a. Outcome is time-dependent
b. Further injury can take place after restoration of blood flow
c. Acute acidosis, hyperkalemia and myoglobin-induced renal failure can be consequences of severe extremity ischemia
d. Ischemia to peripheral nerves and muscles can be tolerated to up to four hours without permanent injury
Answer: a, b, c, d
Local consequences of vascular injuries are generally related to acute arterial occlusion from thrombosis after injury. The results of ischemia distal to the injury sites may lead to limb or organ loss. The degree of tissue loss is related to the adequacy of collateral flow, the sensitivity of distal tissue to ischemia, and the delay involved in repairing the injury and restoring blood flow. With regard to these latter issues, the variability is great. The brain is more sensitive to ischemia because of high basal energy requirements in the absence of glycogen stores. Brain ischemia for longer than 4 minutes results in irreversible injury. The nerves and muscles are much more resilient, tolerating periods of ischemia up to 4 hours without permanent injury. An important principle of vascular repairs, however, is that the outcome is time-dependent, necessitating an aggressive approach and a high priority.
The mechanism of injury from acute arterial ischemia includes both the initial anoxic phase when blood flow is ceased and reperfusion phase after restoration of blood flow. Termed the reperfusion injury, this phase includes the production of toxic metabolites and an inflammatory response which causes significant endothelial damage. The events associated with restoration of arterial blood flow after complete ischemia extend the magnitude and severity of the original insult in skeletal muscle and peripheral nerves. If the severity of ischemia is significant enough to cause skeletal muscle necrosis, rhabdomyalysis with the release of potassium and myoglobin into the systemic circulation follows. Acute acidosis, hyperkalemia, and myoglobin-induced renal failure can occur.
Which of the following statement(s) is/are true concerning the surgical management of vascular injuries?
a. A direct approach through the site of injury is often effective as the initial step
b. Systemic heparinization must be avoided in patients with multiple injuries
c. Reversed saphenous vein from the same extremity is the first choice as an interposition graft for extensive arterial injuries
d. Venous repair should not be attempted in a hemodynamically unstable patient
Answer: b, d
The goal of operative management of vascular injuries is the rapid control of hemorrhage and the restoration of perfusion, with salvage of extremity or organ in jeopardy. In isolated-extremity vascular injury with arterial occlusion, systemic heparin should be administered to avoid propagation of thrombus in vessels distal to the occlusion. In multiple-injury patients, especially those with central nervous system trauma, heparin is inappropriate. The initial steps in the surgical management of vascular injuries is to obtain proximal and distal control of the injured vessel. This is most easily accomplished through uninjured areas adjacent to the injury using incisions normally employed for elective exposure of these vessels. Direct approach to the site of injury is fraught with the hazards of severe hemorrhage and iatrogenic trauma to the vessel itself or adjacent nerves. The management of the arterial injury is determined by the extent of injury. In a repair of more extensive arterial injuries, reversed saphenous vein from an uninjured lower extremity is the first choice for an interposition graft. The repair of concomitant venous injuries is a controversial injury. Proximal extremity veins and the great veins are repaired whenever technically possible to avoid the sequela of venous occlusion. Venous repair should not be attempted, in a hemodynamically unstable patient; rather, ligation should be performed to expedite the operation.
Penetrating injuries to the pancreas and duodenum are uncommon occurring in 4% and 6% of patients, respectively. Which of the following statement(s) is/are true concerning the management of pancreaticoduodenal injuries?
a. The Kocher maneuver is essential for providing exposure for the duodenum
b. A large injury of the duodenum which cannot be closed primarily will always require a pancreaticoduodenectomy
c. Pyloric exclusion involves suture or staple closure of the pylorus, gastrojejunostomy, tube decompression of the duodenum, and placement of a T-tube in the common bile duct
d. Class III injuries of the head of the pancreas should be treated with simple external drainage rather than resection
Answer: a, d
Because of the retroperitoneal location of the duodenum and pancreas and the close proximity to a number of viscera and major structures, isolated penetrating injuries to the duodenum and pancreas are rare. Diagnosis of pancreaticoduodenal injuries depends on adequate exposure. A Kocher maneuver whereby the duodenum and head of the pancreas are mobilized from the retroperitoneal position by excising the lateral peritoneal reflection of the duodenum is essential for this exposure. Most penetrating injuries of the duodenum are simple lacerations that can be repaired primarily. Large injuries to the duodenum are more difficult to repair. Injuries of greater than 50% can lead to luminal compromise if repaired primarily. Treatment with a jejunal patch or duodenojejunostomy with a defunctionalized Roux-en-Y limb of jejunum can avoid the need for pancreaticoduodenectomy and its associated substantial mortality. Since many duodenal repairs are tenuous especially in combination with pancreatic injury and the concern about the digestive action of activated pancreatic enzymes on the repair, the technique of pyloric exclusion has been devised and is advocated by some. Pyloric exclusion involves suture or staple closure of the pylorus and restoration of gastrointestinal continuity by performing a gastrojejunostomy. Tube decompression of the duodenum should be performed in severe duodenal injuries but the biliary tract does not require decompression unless there has been an associated biliary tract injury. The management of pancreatic injuries depends on the location with respect to the head, body, and tail of the gland. Class III injuries of the head of the pancreas involve a relatively severe injury. In almost all situations, these injuries should simply be drained without attempts at resection or emergency internal drainage. If a patient develops a pancreatic fistula, the fistula can be controlled by the drain. If the fistula does not resolve with time, the pancreas can be drained internally at a later date.
A CT scan is performed on this patient. Which of the following statement(s) is/are true concerning the findings on CT scan and the patient’s management?
a. The CT finding that correlates most significantly with intracranial hypertension is compression or obliteration of the basilar cisterns
b. Intracranial pressure monitoring is indicated immediately in any patient with cisternal compression.
c. A brain contusion appears as a very homogeneous high density area in the cerebral cortex
d. Intracerebral hematomas are routinely treated with craniotomy
Answer: a, b
The CT finding which correlates most significantly with intracranial hypertension is compression or obliteration of the basilar cisterns. Not only does this finding portend a stormy intracranial pressure course, but the primary predictor of outcome in patients with this CT picture is the peak level intracranial hypertension occurring during the first 72 hours. Intracranial pressure monitoring should be immediately initiated in any patient with cisternal compression and the intracranial hypertension should be vigorously treated. Intracerebral hemorrhage and cerebral contusion are common after trauma and are readily visualized on CT scan. Brain contusion appears as a focal, heterogeneous density with hemorrhage interspersed with injured tissue. Intracerebral hematomas are generally more homogeneous in their high density appearance. These lesions tend to “blossom” over time due to continued hemorrhage and the development of edema. Therefore, it is important to closely observe and monitor the ICP of such patients because a significant and hazardous mass effect may evolve, requiring surgical extirpation. Cerebral contusions and intracerebral hematomas are treated operatively only when a mass effect results in intracranial hypertension or signs of herniation.
Which of the following statement(s) is/are true concerning the management of chest trauma?
a. The majority of injuries to the chest require surgical intervention
b. The posterior lateral thoracotomy is the optimal approach for emergency thoracotomy
c. Either computed tomography or angiography are suitable methods for detecting aortic disruption in a patient with an abnormal chest x-ray
d. Persistent bleeding associated with a penetrating injury to the chest is often due to injury to an artery of the systemic circulation
Answer: d
The chest radiograph is by far the most important diagnostic study in patients with chest trauma and should be obtained early in all patients. Angiography is the best study to rule out major injury to the great vessels in the chest, and angiography remains mandatory in the majority of patients at risk for aortic disruption who have an abnormal chest radiograph. At the present time, CT scan of the chest appears to have a higher rate of missed injury than angiography for assessment of the aorta and should probably be avoided in patients with abnormal chest films.
The majority of injuries to the chest can be successfully managed without surgical intervention. The routine use of a tube thoracostomy for treatment of hemothorax and pneumothorax is the cornerstone of therapy. Thoracotomy is most often needed for the control of massive bleeding, or bleeding which persists despite tube thoracostomy. About 80% to 85% of hemorrhages within the chest can be treated by tube thoracotomy alone. Even larger and deep lacerations of the lung parenchyma, which bleed with relatively low pressure from the pulmonary circulation, will be controlled by the reinflated lung parenchyma as well as edema in the tissue from the injury. Persistent bleeding is most commonly due to injuries to major proximal branches of the pulmonary circulation or injuries to systemic arteries including intercostal arteries and internal mammary arteries. The choice of position and surgical approach for thoracotomy for thoracic injury is dictated by the nature of the patient’s injuries, the certainty of diagnosis, and the potential for associated injuries involving other body sites. Although the standard postero-lateral thoracotomy provides optimal exposure to the contents of a particular hemithorax, the lateral position of the patient makes access to the other side of the chest or abdomen difficult if not impossible. Therefore, though postero-lateral thoracotomy provides the best access, it can be used only in patients who have injuries isolated to a given hemithorax. In most patients undergoing emergency thoracotomy for chest trauma, an antero-lateral approach must be used in patients supine to allow access to the abdomen and contralateral chest cavity. Although exposure through this incision is considerably more difficult, it is adequate with proper technique. Median sternotomy incision provides excellent exposure to the heart and the great vessels in the anterior mediastinum, but it provides very difficult exposure for repair of injuries to the lungs, descending aorta, chest wall, diaphragm, or esophagus. Therefore, like the postero-lateral thoracotomy, it can be used only when the patient’s injuries can be determined with relative certainty.
The anterior neck is divided into three zones defined by horizontal planes. Which of the following statement(s) is/are true concerning penetrating injuries to the anterior neck?
a. Penetrating injuries to Zone I carry the highest mortality
b. Injuries to Zone II are the most common and the mortality rate is second only to those of Zone I
c. Exposure of Zone III for detection of injuries to the distal carotid artery and pharynx can be quite difficult
d. All hemodynamically stable patients with penetrating injuries to Zone I should have angiography
e. Most vascular lesions in Zone III are best treated by surgical exploration
Answer: a, c, d
The anterior neck is divided into three zones defined by horizontal planes. Zone I represents the base of the neck and it invariably extends from the sternal notch to the top of the clavicles or the cricoid cartilage. Injuries here carry the highest mortality because of the risk of major vascular and intrathoracic injury. Zone II is the mid-body and largest portion of the neck. It extends from the top of Zone I to the angle of the mandible. Zone II injuries are most common but carry a lower mortality rate than either Zone I or Zone III injuries, since the injury is generally apparent and exposure of the vital structures is readily accomplished. Zone III is that part of the neck above the angle of the mandible. The risk of injury to the distal carotid artery, salivary glands and pharynx is greatest in this zone. Exposure in this region can be particularly difficult.
Most surgical groups advocate exploration in the majority of penetrating neck wounds that penetrate the platysma in Zone II and in all patients with clinical signs of tracheal, esophageal, or major vascular injury. Preoperative angiography is generally not required for Zone II injuries because of the relative ease of exposure and control of critical vascular structures. Zone I and III penetrating injuries are selectively managed based on clinical presentation and the result of diagnostic studies. Hemodynamically unstable patients are immediately explored with operative incision based on the most likely source of vascular injury. Zone I injuries are essentially managed similar to mediastinal traversing wounds. Angiography is performed in all hemodynamically stable patients with penetrating wounds to Zone I to identify potential injuries to the thoracic outlet vessels or to plan better operative approach. Angiography is also performed for Zone III injuries, because of the possible inaccessibility of the internal carotid artery lesions or to demonstrate a need for systemic anticoagulation. Furthermore, most of the vascular lesions identified at the base of the skull are best managed by interventional angiography techniques.
Which of the following statement(s) is/are true concerning the definitive management of neck injuries?
Patients with evidence of an acute stroke following penetrating injury involving the carotid artery should be managed with arterial ligation
Unilateral vertebral artery occlusion usually results in a clear neurologic deficit and therefore revascularization is indicated
The combination of esophography and endoscopy improves the accuracy of detecting esophageal injury with penetrating trauma
External drainage is an important aspect of the surgical management of an esophageal injury
Arterial dissection secondary to blunt trauma is best managed by operative exploration and resection of the dissection
Answer: c, d
Blood vessels are the most commonly injured structures in the neck. Major arterial injuries occur in 18% of penetrating neck wounds and major venous injuries in 26%. Blunt vascular injures account for a very small percentage of carotid injuries, however their management is somewhat controversial with treatment highly variable dependent upon the vascular lesion as well as concomitant injuries. When anatomically feasible, pseudoaneurysms are probably best managed by resection. The best treatment for arterial dissection, however, although not completely resolved, would appear to be systemic anticoagulation if possible to prevent propagation, embolization or thrombosis. Resection may not be required in the majority of patients. Penetrating carotid injury most commonly presents with exsanguinating hemorrhage. The indication for repair versus ligation of a carotid injury depends, in part, on the neurologic presentation. Patients without a neurologic deficit and a carotid injury should have restoration of vascular continuity with good neurologic outcome anticipated. Also, patients with all grades of neurological deficits short of coma should have primary vascular repair. Although experience with revascularization of patients suffering acute stroke from arteriosclerotic occlusive disease suggests that hemorrhagic infarction and death may result from revascularization, several reviews of acute revascularization in the trauma patient note that combined morbidity and mortality are significantly less in those patients repaired primarily compared to those managed with arterial ligation. Traumatic injury to the vertebral arteries are now more commonly identified due to the more liberal application of neck angiography. Unilateral vertebral artery occlusion seldom results in a neurologic deficit. Treatment of blunt vertebral artery injury with thrombosis generally is nonoperative: systemic anticoagulation is recommended to avoid further propagation of existing thrombus.
The diagnosis of esophageal injury can be difficult. The sensitivity of esophography in detecting esophageal injuries varies from 50% to 90%; the sensitivity of endoscopy ranges from 29% to 100%. These modalities should be considered complimentary, and when combined have an accuracy of nearly 100%. Since virtually all reported deaths from cervical esophageal injuries are the result of delayed or misdiagnosis, a particularly high index of suspicion is warranted. When injured, the esophagus should be meticulously debrided and repaired primarily in one or two layers. It is important to drain all such wounds, because infection or salivary fistula is not an infrequent complication.
A 25-year-old male is involved in a motor vehicle accident with a significant head injury. Which of the following statement(s) is/are true concerning his injury and management?
a. A single episode of systolic blood pressure < 90 mm Hg occurring during the early period after injury significantly increases the chances of mortality and morbidity
b. Systemic hypertension should be avoided to reduce the risk of intracranial hemorrhage
c. The patient should be vigorously hyperventilated to reduce PaCO2
d. The patient should be heavily sedated and pharmacologically paralyzed after the initial neurologic examination
Answer: a
Brain injury is the most common cause of death in trauma victims, accounting for about half of deaths at the accident site. The injuries are generally the result of blunt trauma, and motor vehicle accidents are the most frequent cause. Head injuries involve not only the primary injury but secondary injuries which can result from the events occurring after the primary insult, due to either the direct consequences of a process initiated by the primary injury or to deleterious outside influences. The occurrence and magnitude of secondary insults is often the determining factor in outcome from brain injury. Since secondary insults, in contrast to primary injuries, are amenable to medical therapy, they are the focus toward which the medical treatment of brain injury is directed. The primary external secondary injury processes occurring following brain injury are hypotension and hypoxia. Hypotension is the number one treatable determinant of severe head injury. A single episode of systolic blood pressure less than 90 mm Hg occurring during the period from injury through resuscitation doubles the mortality and significantly increases the morbidity of any given brain injury. Intracranial hypertension may be considered as being deleterious via two somewhat separate mechanisms—herniation and ischemia. Herniation occurs when a pressure gradient exists across an incomplete barrier such as the tentorium or the falx cerebri. It is deleterious because of the tissue damage that results when herniation occurs. The second aspect of the intracranial hypertension that is deleterious is elevated resistance to cerebral blood flow, resulting in or exacerbating ischemia. Treatment of systemic hypertension is rarely indicated in the head injured patient. There is no evidence that hypertension promotes continued intracranial hemorrhage, and hypertension related to brain injury generally resolves when the intracranial hypertension is controlled. The treatment of intracranial hypertension involves elevating the head of the bed (reversed Trendelenburg position) but should only be performed after complete resuscitation has been accomplished. The confusion and agitation often attendant to head injury renders sedation desirable, therefore, patients with suspected head injury should generally be sedated. Pharmacologic relaxation, however, has the notable effect of limiting the neurologic examination to the pupils and, upon arrival to the hospital, the computed tomography scan. Therefore, its use in the absence of evidence of herniation should be limited to situations which sedation alone is not sufficient to optimize safe and efficient patient transport and resuscitation. When used, short acting agents are strongly preferred. Prophylactic administration of mannitol is not recommended due to volume depleting diuretic effect. In addition, although it is desirable to approximate the lower end of the normal range of PaCO2 during transport of a patient with suspected brain injury, the risk of exacerbating early ischemia by vigorous hyperventilation outweighs the questionable benefit in the patient without evidence of herniation. Therefore, ventilatory parameters consistent with optimal oxygenation and “normal” ventilation are recommended.
Which of the following statement(s) is/are true concerning the biomechanics of penetrating injuries?
e. Stab wounds are associated with significant cavitation
f. A hollow point bullet is associated with an enlarged area of injury
g. A high velocity gunshot wound creates a vacuum pulling clothing, bacteria, and other debris into the wound
h. The frontal area of impact of a bullet is determined by the caliber of the bullet
Answer: b, c
Penetrating trauma involves the transfer of energy to a relative small tissue area. The kinetic energy of a bullet disrupts and fragments cells and tissues, moving them away from the path of the bullet. The actual size of the frontal area of impact is determined by three factors—profile, tumble (spin and yaw), and fragmentation. A knife or jacketed bullet does not deform significantly during impact, whereas a hollow-point bullet flattens, spreads, and fragments on impact and therefore enlarges the area of injury. Low energy missiles including knives and other objects produce damage only by sharp cutting edges. Cavitation is minimal, and injury can be predicted simply by tracing the pathway of the weapon within the body. Low, medium and high velocity gunshot wounds, however, produce damage not only to tissue directly in the path of the missile but also produce cavitation injury to tissues in close proximity to the impact. The size of the cavitation injury is directly proportional to the bullet’s velocity. The essential difference between high velocity weapons and low and medium velocity weapons is that the higher velocity weapons have a much larger cavity or pressure cone than low-and medium-velocity missiles. The temporary cavity extends well beyond the actual bullet tract, producing a wider injury. The vacuum created by the cavitation pulls clothing, bacteria, and other debris from the surrounding areas into the wound, creating the additional risk of contamination.
In which of the following clinical situations is peritoneal lavage indicated?
i. A patient with suspected intraabdominal injury who will undergo prolonged general anesthesia for another injury outside the abdomen
j. A patient with a high velocity abdominal gunshot wound
k. A patient with an abdominal knife wound
l. A hemodynamically unstable patient with a high suspicion of intraabdominal hemorrhage
m. A patient with major noncontiguous injuries (i.e., chest and lower extremity)
Answer: a, c, e
Peritoneal lavage is a standard technique to detect significant intraabdominal hemorrhage after blunt trauma. Its applicability after low-velocity gunshot or stab wounds is less clear, but it has no place in the evaluation of high-velocity gunshot wounds. Abdominal paracentesis can be used in place of peritoneal lavage when the suspicion of intraabdominal hemorrhage is high and time is critical. Specific indications for peritoneal lavage and blunt trauma include a number of conditions such as a patient with major noncontiguous injuries, a patient with suspected intraabdominal injury in whom physical examination is unreliable or impossible due to the need for prolonged general anesthesia for another injury. Peritoneal lavage is not useful for patients with abdominal gunshot wounds; all of these patients require immediate laparotomy. When local examination of a stab wound suggests penetration to the anterior fascia and peritoneum, diagnostic peritoneal lavage may help discriminate between those with significant and insignificant injuries.
Physiologic responses to hypothermia include:
n. Tachycardia regardless of core temperature
o. Tachypnea regardless of core temperature
p. Pupillary dilatation and loss of cerebral autoregulation at temperatures below 26°C
q. A cardiac rhythm contraindicates cardiopulmonary resuscitation even in the absence of a palpable pulse
Answer: c, d
The physiologic response to hypothermia is one of transitional changes, with few exact temperature-dependent responses. Broadly speaking, the transition from a “safe zone” of hypothermia (where physiologic adaptations to heat loss are working) to a “danger zone” of hypothermia occurs between 33°C and 30°C. The cardiovascular response includes tachycardia followed by progressive bradycardia which starts at about 34°C , and which results in a 50% heart rate decrease at 28°C. Asystole occurs below 25°. Due to difficulty in palpating weak, bradycardic pulses in cold, stiff hypothermic patients, the presence of an organized rhythm should be taken as a sign of life that contraindicates CPR, despite the absence of a palpable pulse. Respiratory drive is increased during the early stages of hypothermia, but below 30°C progressive respiratory depression occurs, resulting in a decrease in minute ventilation.
The neurologic response to hypothermia is heralded by progressive loss of lucidity and deep tendon reflexes, and eventually flaccid muscular tone. Pupillary dilatation and loss of cerebral autoregulation occur at temperatures below 26°, and electroencephalography becomes silent at 19–20°. It is important, however, to remember that patients have been revived with core temperatures as low as 17°C, and therefore the saying “No one is dead until warm and dead”.
Which of the following statement(s) is/are true concerning the injury pattern in patients with blunt versus penetrating injuries?
r. Solid organs are most frequently injured following blunt trauma
s. The liver is the most frequently injured organ in both penetrating and blunt trauma
t. Major vascular injuries occur much more commonly in penetrating trauma than with blunt abdominal trauma
u. Injury patterns for blunt abdominal trauma in children are different than adults whereas with penetrating trauma no such difference exists
Answer: a, c, d
Most series list the spleen as the most commonly injured intraabdominal organ after blunt trauma. However, the means of diagnosis may affect this finding since small liver injuries, often detected only on CT scan of the abdomen, may go unreported while splenic injuries are likely to be clinically significant and require surgical intervention. Solid organs are most frequently injured from blunt trauma since the sudden application of pressure to the abdomen is more likely to rupture a solid organ than a hollow viscus, and this accounts for the greater incidence of solid organ injury. More elastic tissues of young people tolerate trauma better than those of older people, and this accounts, in part, for the differences in injuries between children and adults with blunt abdominal trauma. Major vascular injuries occur in over 10% of patients sustaining penetrating trauma but occur in only approximately 2% of patients with blunt trauma.
An 18-year-old male suffers a gunshot wound to the abdomen, resulting in multiple injuries to the small bowel and colon. Which of the following statement(s) is/are true concerning this patient’s perioperative management?
v. A multi-agent antibiotic regimen is indicated
w. Antibiotics should be continued postoperatively for at least 7 days
x. Laparotomy, as a diagnostic test for postoperative sepsis, should be considered
y. The incidence of postoperative wound or intraabdominal infection would be increased in association with a colon injury
Answer: d
Post-traumatic intraabdominal infection is almost always the result of gastrointestinal tract contamination. Penetrating trauma accounts for the largest proportion of these infections. Because of the higher bacterial counts, the colon is consistently associated with a higher incidence of infectious complications than isolated gastric, duodenal, or small bowel injuries. The precise incidence of intraabdominal or incisional wound infection after colonic injuries depends on factors present at the time of injury (blood loss, degree of contamination, and other associated injuries) and on whether the wound is closed or left open. The use of perioperative antibiotics for trauma has been investigated extensively. Most studies have demonstrated that single-agent cephalosporins are at least as effective as multi-agent regimens in retarding intraabdominal abscess or wound infections resulting from a variety of contaminated traumatic wounds.
Fever, leukocytosis, tachycardia, the development of a paralytic ileus, increased fluid requirements, and failure to wean from a mechanical ventilation may all represent warning signs of the development of intraabdominal infection. CT is the single most useful diagnostic tool in this clinical setting because it yields considerable information with regard to organ injury in the presence of intraabdominal abscesses or fluid collections. Laparotomy, as a diagnostic tool for unexplained sepsis, has a low-yield in critically ill trauma patients and should not be used routinely.
A middle-aged man is undergoing laparotomy for blunt abdominal trauma. The spleen and liver are both found to be injured. Which of the following statement(s) is/are true concerning the management of these injuries?
z. If the patient has multiple other abdominal injuries and hypotension, splenic salvage should not be attempted
aa. The incidence of life-threatening sepsis in the adult following splenectomy is no greater than in the normal population
bb. All liver injuries regardless of their depth require external drainage
cc. The Pringle maneuver should control all bleeding from hepatic parenchymal vessels
dd. If concern for a biliary fistula from the liver parenchyma exists, a T-tube should be placed even if the common bile duct is otherwise normal
Answer: a
Solid abdominal organs such as the liver and spleen, are most commonly injured during blunt abdominal trauma. The management of splenic trauma has been the subject of major reexamination in the last few decades. Historically, splenic injuries are routinely treated with splenectomy. With increased appreciation of the danger of post-splenectomy sepsis, splenic salvage procedures and nonoperative management of these injuries have become well accepted. This is particularly true in children. The incidence of post-splenectomy sepsis varies from 0.5% to as much as 12% to 15%, depending on the age and underlying disease. The incidence is inversely related to age and is higher with underlying hematologic disorders such as lymphoma or thalassemia. The incidence of life-threatening sepsis in adult trauma patients is low, but higher than in the normal population. Splenic salvage should not be attempted if the patient has protracted hypotension or other severe injuries or if undue delays are encountered in an attempt to repair the spleen.
Simple lacerations of the liver found at the time of surgery do not require drainage unless they are deep into the liver parenchyma, in which case they have a high probability of postoperative bile leakage. Biliary fistulas usually will close spontaneously, and major extrahepatic ductal injuries are rare. A T-tube placed in an otherwise normal common bile duct is inappropriate unless the extrahepatic biliary tree is injured. In the event that bleeding continues despite segmental ligation of parenchymal vessels, the structures of the porta hepatis should be compressed as a diagnostic maneuver (Pringle maneuver). If the bleeding stops, it is assumed to originate from the portal veins or hepatic artery. If the bleeding continues, it is presumed to arise principally from the hepatic veins or inferior vena cava.
Which of the following conclusions can be drawn from prospective randomized studies involving restoration of circulation in the field?
ee. Pneumatic anti-shock garment is of benefit only in patients with a field blood pressure less than 50
ff. Patients with major vascular injury should not receive intravenous fluid infusion until bleeding can be controlled in the operating room
gg. Hypertonic saline, used as resuscitation fluid, provides no benefit to patients
hh. Hypertonic saline has been shown to exacerbate bleeding and precipitate coagulopathy
Answer: a, b
The most common cause of death during the first hour after injury is hemorrhage. Therefore, after establishment of patent airway and adequate air exchange, the next priority is to support the circulation. The standard of care in the pre-hospital setting for hypotensive patients has been volume replacement and application of pneumatic anti-shock garment. In a recent large prospective randomized study, pneumatic anti-shock garments offered no survival advantage and actually increased mortality when used in patients with thoracic injuries. On the other hand, there was the suggestion that patients with a field blood pressure less than 50 mm Hg may benefit from this treatment. A second prospective study confirmed this result, indicating that the pneumatic anti-shock garment is of value to selected patients with field blood pressure less than 50 mm Hg. A recent clinical study has also demonstrated that internal hemorrhage from major vascular injuries should not be treated with intravenous fluid infusion until bleeding can be controlled in the operating room. In the hypotensive state, such major vascular injuries have a chance to clot and temporarily stop bleeding. But if intravenous volume restores blood pressure, the clot may dislodge and the rate of bleeding significantly increases. This may lead to both loss of oxygen carrying capacity and clotting factors, and ultimately exsanguination. Hypertonic saline restores intravascular volume and blood pressure to near normal very rapidly. The prospective randomized trial of normal saline versus hypertonic saline demonstrated a significant improvement in survival when the data were normalized to a select group of patients. There was no evidence that nontamponaded bleeding was exacerbated by the use of hypertonic saline despite the fact that blood pressure and intravascular volume increased.
Which of the following statement(s) is/are true concerning hypothermia following traumatic injury?
ii. The majority of patients presented to a level I trauma center are hypothermic at some time
jj. The initial temperature for trauma-associated hypothermia is associated with no seasonal variation
kk. Moderate levels of hypothermia (34°–32°C) has no effect on mortality in the trauma patient
ll. The coagulation system is most affected in hypothermic patients who have sustained major trauma
Answer: a, b, d
Mild hypothermia is very common following traumatic injury and is considered a form of secondary accidental hypothermia. It has been reported that 57% of trauma patients admitted to a level I trauma center are hypothermic at some time, with temperature loss most significant in the Emergency Room. This effect appears to have no seasonal variation. Although the mortality rate for moderate (28°–32°C) degrees of primary accidental hypothermia is only approximately 21%, the same level of hypothermia in surgical patients who are victims of trauma can be associated with mortality rates approaching 100%. Hypothermia affects multiple systems, however, the system most affected in patients sustaining major trauma are those involved in clotting. This effect seems to involve both abnormalities in platelet and clotting function.
Which of the following statement(s) is/are true concerning injuries to the chest wall?
mm. The mortality rate currently associated with sternal fractures is as high as 25–30%
nn. The severe ventilatory insufficiency associated with a flail chest is due to the paradoxical motion of the involved segment of chest wall
oo. In most cases of an open pneumothorax, or sucking chest wound, surgical closure is necessary
pp. Persistent chest tube bleeding at a rate greater than 200 ml/hour for four hours, or greater than 100 ml/hour for eight hours is an indication for thoracotomy for control of hemorrhage
qq. A 20% incidence of splenic injury is associated with fractures of ribs 9, 10 and 11 on the left
Answer: c, d, e
Rib fracture is the most common injury associated with blunt chest trauma and may occur directly at the site of force or laterally as the result of significant antero-posterior compression of the chest. The location area of the rib fracture may be indicative of associated injuries. A 20% incidence of splenic injury is associated with fracture of ribs 9, 10, and 11 on the left with a similar association with right lower rib fractures and hepatic parenchymal injuries. The mortality rate associated with sternal fractures in older series was as high as 25–30%, mainly because of other injuries to the chest, such as aortic transection, cardiac contusion, tamponade or tracheo-bronchial rupture. More recent studies have suggested a change in the pattern and severity of injuries associated with sternal fracture. Widespread improvements in automobile safety have likely contributed to this change such that isolated sternal fractures may result from shoulder belt use and may not necessitate hospital admission in the stable patient. A flail chest occurs when consecutive ribs are fractured in more than one place, creating a free-floating segment of the chest wall. The creation of a free-floating segment may result in paradoxical chest wall motion with respiration. The intact chest wall expands during inspiration, but the negative intrathoracic pressure generated causes the flail segment to move inappropriately inward. Historically it was believed that the paradoxical motion was the cause of severe ventilatory insufficiency associated with the flail chest. Gradually, understanding of the pathophysiology of the flail chest has evolved. The ventilatory impairment is not simply due to paradoxical motion of the chest wall, but rather due to underlying pulmonary parenchymal injury in combination with the hypoventilation and splinting that results from the pain of multiple contiguous rib fractures. The open pneumothorax, or sucking chest wound, is an uncommon injury usually caused by impalement, high-speed motor vehicle accident, or shotgun blast, which causes a large chest wall defect. The diagnosis of a sucking chest wound can be made on simple inspection of the chest wall and hearing the flow of air through the wound. The defect should be occluded immediately with an impermeable dressing, essentially converting the situation to a closed pneumothorax. Tube thoracostomy is then performed to re-expand the lung. The chest wall defect usually requires operative debridement and formal chest wall closure. A hemothorax is the accumulation of blood in the pleural space and it occurs in 50–75% of patients with severe blunt or penetrating chest trauma. Massive hemothorax (i.e., larger than 1000–1500 ml) may require thoracotomy. Persistent bleeding, at a rate of > 200 ml/hour for four hours, or > 100 ml/hour for eight hours, is also an indication for thoracotomy. If the patient manifests any hemodynamic instability during the period of observation, urgent thoracotomy is mandatory.
A 22-year-old male driving a car at a high speed and not wearing a seatbelt, leaves a road and crashes with a full frontal impact into a tree. Which of the following injury patterns may be predictable from this type of motor vehicle accident?
rr. Orthopedic injuries involving the knees, femurs, or hips
ss. Laceration to the aorta
tt. Hyperextension of the neck with cervical spine injury
uu. Diaphragmatic rupture due to marked increase in intraabdominal pressure
Answer: a, b, c
With frontal impact, when the vehicle stops abruptly, unrestrained front-seat occupants move in one of two predictable pathways—down and under the dashboard or up and over the steering wheel. With the former movement, the knees strike the dashboard, and the upper legs absorb the primary energy transfer. Dislocated knees, fractured femurs, and posterior fracture dislocation of the hips are expected injuries. After the knees impact, the upper body flexes forward and up and over the steering wheel. The chest or abdomen impacts the steering wheel and the head impacts the wind shield.
Predictable injury patterns following the up-and-over component of a frontal impact include the following: 1) anterior chest wall compression; 2) compression injuries to both hollow and solid abdominal viscera; 3) shear injuries such as lacerations to the aorta or liver, kidneys or other solid viscera; 4) injury to the brain from direct compression with scalp lacerations, skull fractures and cerebral contusions or from deceleration or shear forces; 5) acute neck flexion, hyperextension or both resulting in cervical spine injury.
Three-point passenger restraints and air bags, although overall very effective in reducing injury, can cause specific related injuries. Common injuries when lap belts are incorrectly strapped above the anterior iliac spine include compression injuries of intraabdominal organs (liver, pancreas, spleen, small bowel, large bowel), increased intraabdominal pressure and diaphragmatic rupture.
Which of the following statement(s) is/are correct concerning the pathophysiology of frostbite?
vv. Frostbite injury may have two components: initial freeze injury and a reperfusion injury that follows during rewarming
ww. The formation of extracellular ice crystals in the tissue begins to occur at -10°C
xx. The release of oxygen free radicals and arachidonic acid metabolites aggravates vasoconstriction and platelet and leukocyte aggregation
yy. Experimental evidence suggests that a substantial component of severe cold injury may be mediated due to platelet aggregation
Answer: a, c
Recent evidence suggests that frostbite injury may have two components: the initial freeze injury, and a reperfusion injury that occurs during rewarming. The initial response to tissue cooling is vasoconstriction and arterio-venous shunting, intermittently relieved by vasodilatation. With prolonged exposure, this response fails, and the temperature of the freezing tissues will approximate ambient temperature until -2°C. At this point, extracellular ice crystals form, and as these crystals enlarge, the osmotic pressure of the interstitium increases resulting in movement of intracellular water into the interstitium. Cells begin to shrink and become hyperosmolar, disrupting cellular enzyme function.
During rewarming, red cell, platelet and leukocyte aggregation is known to occur and results in patchy thrombosis of the microcirculation. These accumulated blood elements are thought to release, among other products, the toxic oxygen-free radicals and the arachidonic acid metabolites which further aggravate vasoconstriction and platelet and leukocyte aggregation. Recent experimental evidence suggests that a substantial component of severe cold injury may be neutrophil-mediated in that a monoclonal antibody to neutrophil-endothelial and neutrophil-neutrophil adherence can markedly ameliorate the pathology of severe injury.
The management of a patient with frostbite includes:
zz. Gradual spontaneous warming
aaa. Emersion of the tissue in a large water bath with a temperature of 40–42°C
bbb. Immediate initiation of prophylactic antibiotics
ccc. Systemic anticoagulation with heparin
ddd. Immediate debridement of necrotic tissue
Answer: b
The treatment of frostbite with rewarming should begin in the Emergency Room and not in the field. Gradual, spontaneous warming is generally inadequate and delayed thawing, or rubbing the injured part in ice or snow often results in marked tissue loss. Rapid rewarming should be achieved by immersing the tissue in a large bath of 40–42°C. The water should feel warm, but not hot to the normal hand. The skin should be gently but meticulously cleansed, air dried, and affected area elevated to minimize edema. Infection develops in only about 13% of urban frostbite victims, but half of these infections are present at the time of admission. Therefore, most clinicians reserve antibiotics for identified infections. Following rewarming, the treatment goals are to prevent further injury while awaiting demarcation of the irreversible tissue destruction. The use of sympathetic blockade, surgical sympathectomy, and intraarterial vasodilating drugs has generally been ineffective. Heparin, thrombolytic agents, and hyperbaric oxygen have also failed to demonstrate any substantial treatment benefit. The difficulty in determining the depth of tissue injury and cold injury has led to a conservative approach to the care of frostbite injuries. As a general rule, amputation and surgical debridement are delayed for 2–3 months unless infection with sepsis intervenes. The natural history of full thickness frostbite is gradual demarcation of the injured area with dry gangrene and mummification clearly delineating a nonviable tissue.
There are a number of injuries associated with common orthopedic injuries. Which of the following diagnosed orthopedic injuries is associated with the injury listed?
eee. Sternal fracture—cardiac contusion
fff. Posterior dislocation of the knee—popliteal artery thrombosis
ggg. Pelvic fracture—ruptured bladder or urethral transection
hhh. Posterior dislocation of hip—-sciatic nerve injury
Answer: a, b, c, d
PATTERNS OF INJURY TO THE HEAD, NECK, TRUNK, AND EXTREMITIES ASSOCIATED WITH ORTHOPEDIC INJURIES
Diagnosed Injury Associated Injury
Fracture—temporal, parietal bone Epidural hematoma
Maxillofacial fracture Cervical spine fracture
Sternal fracture Cardiac contusion
First and second rib fracture Descending thoracic aorta, intraabdominal bleeding
Fractured scapula Pulmonary contusion
Fractured ribs 8–12, right Lacerated liver
Fractured ribs 8–12, left Lacerated spleen
Fractured pelvis Ruptured bladder, urethral transection
Fractured humerus Radial nerve injury
Supracondylar humerus Brachial artery injury
Distal radius fracture Median nerve compression
Supracondylar femur fracture Thrombosis popliteal artery
Anterior dislocation shoulder Axillary nerve injury
Posterior dislocation of hip Sciatic nerve injury
Posterior dislocation of knee Popliteal artery thrombosis
Correct statement(s) concerning cold injury include:
iii. Chilblain is a form of local cold injury characterized by pruritic papules, macules, or plaques on the skin associated with repeated exposure to cold temperatures
jjj. Trenchfoot is a freeze injury of the hands or feet due to chronic exposure to cold, wet conditions below freezing
kkk. Frost nip is reversible with warming of the tissue and will result in the return of sensation and function with no tissue loss
lll. Characteristic large blisters can be seen with all degrees of frostbite
Answer: a, c
Cold injuries limited to digits, extremities, or exposed surfaces are the result of either direct tissue freezing (frostbite) or more chronic exposure to an environment just above freezing (Chilblain or pernio; trenchfoot). Chilblain or pernio are descriptive forms of local cold injury characterized by pruritic, red-purple papules, macules, plaques or nodules in the skin. This pathology appears to be provoked by repeated exposure to cold but not freezing temperatures. Trenchfoot or cold emersion foot describes a non-freezing injury of the hands or feet, typically in sailors, fishermen, or soldiers resulting from chronic exposure to wet conditions and temperatures just above freezing. Frost nip is the mildest form of cold injury characterized by initial pain, pallor, and subsequent numbness of the affected body part. The injury is reversible and warming of the cold tissue results in return of sensation and function with no tissue loss. Frostbite is more severe and common form of cold injury and essentially describes local freezing of tissues. The mildest form (first degree injury) is associated with hyperemia and edema but without blistering. Second, third and fourth degree frostbite have progressive degrees of tissue injury and are noted by either characteristic clear blisters (second degree) or more hemorrhagic vesicles which are generally smaller than second degree blisters (third degree frostbite). In fourth degree frostbite, tissue necrosis, gangrene and full thickness tissue loss can be seen.
A 37-year-old man driving an automobile travelling at a rapid speed hits a tree. At arrival to the Trauma Center, aortic disruption is suspected. Which of the following statement(s) is/are true concerning the patient’s diagnosis and management?
mmm. If undiagnosed, a thoracic aortic disruption is associated with a 50% mortality within the first 24 hours
nnn. Transesophageal echocardiography is a promising new modality for the diagnosis of aortic injury
ooo. Repair of aortic disruption is best completed with cardiopulmonary bypass
ppp. Pharmacologic control of blood pressure with sodium nitroprusside should be used routinely in the preoperative management
Answer: a, b
Blunt injuries to the thoracic aorta occur in as many as 20% fatalities due to motor vehicle accidents. About half of these patients die at the scene. It is estimated that of the 50% who survive the initial injury, half will die within the first 24 hours and 90% will die within 10 weeks without surgical treatment. Blunt aortic disruption is associated with the mechanism of abrupt deceleration. Therefore, this mechanism of injury should lead to high index of suspicion. A chest radiograph is a useful screening procedure. Abnormal findings on chest film, or suspicion of the injury, must be aggressively investigated. Due to the very high morbidity of missed injuries, angiography is the diagnostic study of choice in patients at significant risk. Transesophageal echocardiography is a promising modality for the diagnosis of aortic injury, especially in patients who cannot be transported to the angiography suite. Early experience has shown transesophageal echo to be a very sensitive method, with very few missed injuries in experienced hands.
Injuries to the aorta require surgical repair. The technique of aortic repair has been the subject of some controversy primarily due to the risk of spinal cord ischemia with cross clamping of the thoracic aorta. The complete use of cardiopulmonary bypass with full heparinization, however, has been shown to increase the mortality of patients who have other cerebral and vascular injuries, and is probably contraindicated in the blunt trauma patient. Most surgeons favor cross clamping of the aorta with expeditious repair of the injury. Rapid surgical repair is vital to survival of the patients. Preoperative management of patients with aortic disruption involves careful control of blood pressure and avoidance of hypertension. Pharmacologic control of blood pressure is indicated to avoid possible rupture before surgical repair. The use of sodium nitroprusside, however, should be avoided in patients with head injuries because the vasodilatory effect of this drug may cause an increase in intracranial pressure. A short-acting beta agonist such as esmolol or labetolol is probably the best choice if blood pressure control is needed.
Which of the following statement(s) is/are true concerning endotracheal intubation at the site of injury?
qqq. Bag valve mask systems are equally as efficient as endotracheal intubation for early management of the trauma patient
rrr. Paramedic intubation in the field is successful in over 90% of cases
sss. Indications for intubation in the field include respiratory distress, significant head injury, severe chest injury and hypovolemic shock
ttt. If patients clench their teeth violently, endotracheal intubation is impossible without the use of paralytic agents
Answer: b, c
The most immediately life-threatening problem to the injured patient is loss of airway patency and therefore this is the first priority of the first response team upon arrival at the injury site. Basic life support skills such as suctioning, placement of oropharyngeal airways, the use of a bag mask device are usually sufficient at least to temporarily restore oxygenation at the injury site. On the other hand, approximately 10% of patients require endotracheal intubation and up to 20% would benefit from field intubation. Endotracheal intubation is the best procedure for airway control in patients who are in shock, have abnormal breathing patterns, or who are unable to protect their airways due to unconsciousness. Endotracheal intubation is far superior than that of bag valve mask systems because it provides larger total volumes and less risk of aspiration.
Indications for endotracheal intubation in the field should include respiratory distress, hypovolemic shock, unconsciousness, significant head injury, and severe chest injury. Reported paramedic intubation success rates range between 90 and 98% in the literature, and complications are rare. On the other hand, there are problems with intubation at pre-hospital sites. Patients with head injuries may have C-spine injuries so in-line mobilization techniques are necessary to insure intubation without further injury to the cervical spine or cord. Patients often clench their teeth in which case either nasotracheal intubation or the use of paralytic agents such as succinylcholine may be necessary for successful intubation.
Which of the following statement(s) concerning the operative approach to abdominal trauma is/are correct?
uuu. Pelvic hematomas associated with pelvic fractures should be explored
vvv. Central retroperitoneal hematomas should be explored after control of other injuries within the peritoneal cavity
www. Stable hematomas in the perinephric space lateral to the midline should be explored to rule out renal injury
xxx. The initial approach is control of hemorrhage by packing and controlling ongoing contamination from enteric injuries
Answer: b, d
Once the abdomen is opened at laparotomy for trauma, obvious blood and clot is sequentially removed, first from the lower abdomen and then from the upper abdomen by packing all four quadrants of the abdomen. Any areas found to be a source of hemorrhage can be repacked. Obvious hollow viscus wounds should be rapidly sutured or controlled with noncrushing clamps. Once hemorrhage is controlled by packing and ongoing contamination is stopped, time is then taken to allow resuscitation of the patient’s circulating blood volume. Retroperitoneal hematomas may be the source of exsanguinated hemorrhage if rupture into the free peritoneal cavity has occurred. If not, these can be left for investigation at a later time, depending on the location. Hematomas of the pelvis that are associated with pelvic fractures should not be disturbed. Similarly, stable hematomas of the perinephric space lateral to the midline are also best left undisturbed. Central hematomas that may involve injuries to the major vascular structures, pancreas or duodenum are noted and explored after control of injuries within the peritoneal cavity.
Which of the following statement(s) is/are true concerning trauma involving children?
yyy. The greater head/body ratio in children compared to adults leads to a higher frequency of head injuries in children
zzz. Unfused cranial sutures and open fontanels serve as a protective mechanism against intracranial hemorrhage
aaaa. A greater propensity to hypothermia is seen in children
bbbb. A propensity to single organ system injury is seen in the child
Answer: a, c
The smaller size of pediatric patients results in an increased likelihood of multiple system trauma because of the force of impact is dissipated over a relatively small area. A higher frequency of head injuries in children is partially explained by the proportionately greater head/body ratio, the thin skull, and the weaker supporting cervical musculature. In infants with unfused cranial sutures and open fontanels, intracranial hemorrhage can be perfuse and result in shock. The protuberant abdomen of the child obtains little protection from either the thoracic cage or pelvis, accounting for a higher incidence of intraabdominal injuries.
The physiologic response to hypovolemia after pediatric trauma is characterized by the immediate constriction of small and medium-sized arteries, thus maintaining normal blood pressure. Decompensation generally occurs with a blood volume deficit of 20% to 25%. Tachycardia, tachypnea, diminished peripheral perfusion, and change in the level of consciousness are better potential indicators of early shock than blood pressure. The thin skin, lack of subcutaneous fat, and large surface area/body weight ratio all contribute to the propensity of the young child for hypothermia.
Indications for Cesarean section during laparotomy for trauma include:
cccc. Maternal shock after 28 weeks gestation
dddd. Unstable thoracolumbar spinal injury
eeee. Mechanical limitation for maternal repair
ffff. Maternal death if estimated gestational age is at least 28 weeks
nswer: b, c, d
The indications for exploratory laparotomy in a pregnant patient are the same as in all other trauma patients. However, Cesarean section should not be added unless indicated due to the prolongation of operative time and the increase in blood loss (approximately 1 liter). Vaginal delivery is always encouraged even in the postoperative period. During laparotomy for trauma, indications for Cesarean section are as follows:
1. Maternal shock, pregnancy near term
2. Threat to life from exsanguination
3. Mechanical limitation for maternal repair
4. Risk of fetal distress exceeding risk of prematurity
5. Unstable thoracolumbar spinal injury
The outcome of postmortem C-section depends on the duration of the gestation and the time interval between maternal death and delivery. Under optimal conditions, at 26 to 28 weeks gestation, estimated fetal survival is about 50%. Post-mortem C-section is justified if the estimated age is about 26—28 weeks. If the time interval between maternal death and delivery is less than 5 minutes, the fetal prognosis is considered excellent. If the time interval since maternal death is prolonged to about 20 minutes, fetal prognosis is poor.
A 75-year-old man is involved in a motor vehicle accident. Which of the following statement(s) is/are true concerning this patient’s injury and management?
gggg. Acceptable vital sign parameters are similar across all age groups
hhhh. Hypertonic solutions should not be used for resuscitation due to concerns for fluid overload
iiii. The patient would be more prone to a subdural hematoma than a younger patient
jjjj. There is no role for inotropic agents in the management of this patient
Answer: c
Although most principles of management of the elderly trauma patient are similar to their younger counterpart, some important differences must be noted. Evaluating the circulatory system following injury in the elderly, it must be remembered that elderly patients most likely are accustomed to a higher than normal blood pressure. Thus, while a systolic blood pressure of 100 mm Hg is not alarming in a 25 year old, in a 75 year old, this may very well represent hypotensive shock if the “normal” pressure is 150 mm Hg systolic. Recent reports have suggested that pulmonary arterial catheters can be useful in the monitoring of patients with evidence of shock or hypoperfusion or history of intercurrent disease. In patients with a low pulmonary capillary wedge pressure, volume replacement can be provided as needed, however, in the face of an elevated pulmonary capillary wedge pressure, inotropic support may be of benefit. Lactated Ringer’s solution remains the resuscitation fluid of choice in the elderly patient. However, the initial experience with hypertonic solutions have been very favorable. Hypertonic fluids can reduce elevated blood pressures and improve cardiac performance with much smaller volumes when compared to isotonic solutions.
Cerebral atrophy accompanies aging. In addition, the cerebral vasculature is fragile, particularly the veins. The combination of these factors make the elderly more prone to develop subdural hematomas, which may initially be subtle.
Important physiologic alterations of pregnancy which may alter the injury response include:
kkkk. Increased cardiac output
llll. Expanded plasma volume
mmmm. Decreased fibrinogen and clotting factors
nnnn. Partial obstruction of the inferior vena cava
Answer: a, b, d
A number of systems have been developed in an effort to allow comparison of trauma injuries and trauma patients among institutions. Which of the following statement(s) is/are true concerning trauma scoring systems?
oooo. The Revised Trauma Score uses the physiologic parameters of blood pressure, heart rate, and head injury to mathematically assess injury severity
pppp. The Abbreviated Injury Scale (AIS) is a specific anatomic index
qqqq. The Injury Severity Score (ISS) correlates not only the severity of the injury but adjusts for patient age and comorbid risk factors
rrrr. The Triss System is the most complete system in combining trauma score and anatomic component as well as patient age
Answer: a, b, d
Many systems have been developed in an effort to allow comparison of trauma injuries and trauma patients among institutions. The impetus for injury severity scoring system is provided by the need to identify and classify severely injured patients in the pre-hospital phase, to predict mortality, to assess results, and to improve communication. The Revised Trauma Score has been the most widely applied as well as the most useful scoring system for the initial evaluation of trauma victims. It assumes that the physiologic parameters of blood pressure, respiratory rate, and head injury (assessed by the Glasgow Coma Score) can be used mathematically to assess injury severity and predict the most timely and sophisticated medical care. The Abbreviated Injury Scale (AIS), initially devised for blunt trauma and subsequently updated to include penetrating trauma, assesses the severity of nonfatal injuries determined in six different body areas. Thus, it is a specific anatomic index. The Injury Severity Score (ISS) is calculated by assigning the AIS values to each injury in six body parts and then mathematically squaring the three most severely injured areas and adding the total. Unfortunately, this system does not adjust for patient age or patient-related comorbid risk factors. The Triss methodology is of great importance because it attempts to combine the trauma score, or physiologic component, and the ISS, or anatomic component. It also incorporates the patient’s age. The Triss method yields a specific probability of survival, and is recommended for use by the American College of Surgeons Committee on Trauma to be used to maintain a trauma registry and quality assurance program.
Alterations in the immunologic response after a major trauma include:
ssss. Decreased CD3 and CD4 population
tttt. Depression of neutrophil antimicrobial functions including chemotaxis and phagocytosis
uuuu. Decreased levels of pro-inflammatory cytokines including tumor necros