PEM Board Review

Chapter 15: Surgical Emergencies: Orthopedic, Thoracic, and Neurosurgical

Back Pain: The traditional teaching regarding back pain in children is that it is pathologic until proven otherwise, but more recent literature has shown that back pain is more common and benign causes more prevalent than previously thought. Children younger than 10 years of age are more likely to have a definitive cause identified for their back pain than older children and adolescents. In addition to this age cutoff, other findings that warrant further evaluation include nighttime pain, constitutional symptoms (eg, fever, weight loss, anorexia, fatigue), neurologic signs and symptoms, and pain that persists or worsens with conservative management.

In a child, back pain and tenderness and the lack of neurologic symptoms point to a diagnosis of diskitis or vertebral osteomyelitis. The initial evaluation should include plain radiographs looking for disc space narrowing, vertebral end plate abnormalities (diskitis), or lytic lesions (eg, osteomyelitis, tumor). Radiographs may appear normal early in the course of infection. When plain radiographs are normal or equivocal, further imaging with either bone scan or MRI can be used to establish the diagnosis.

Blood tests should be ordered to look for evidence of infection as well as to exclude hematologic malignancies such as leukemia. Erythrocyte sedimentation rate and C-reactive protein usually are elevated in both diskitis and vertebral osteomyelitis. A peripheral blood leukocytosis with a neutrophil predominance may be present. As with other bone and joint infections, the causative bacterial agent may be isolated from blood cultures in up to 50% of cases. Staphylococcus aureus is the most common organism identified in diskitis and vertebral osteomyelitis. Empiric therapy with antistaphylococcal antibiotics should be initiated while awaiting culture results. 3-6 weeks of tx is required.

Controversy surrounds the cause of diskitis, but most cases are presumed to be bacterial in origin. Whether diskitis and vertebral osteomyelitis represent distinct clinical entities or stages of the same disease process is not clear. Prodromal symptoms, including malaise, fatigue, and upper respiratory tract complaints, frequently precede the fever and back pain in patients who have diskitis. Younger children (<3 years) tend to present with limp or refusal to walk; older children complain of more specific back pain and stiffness. Some children experience abdominal pain. Neurologic signs and symptoms are rare and may indicate development of an epidural abscess. Physical examination findings include fever, limited spinal range of motion, and focal spinal tenderness. The patient's resting posture, gait, and degree of spinal mobility should be observed.

Although functional or nonspecific back pain does occur in the pediatric population, it is a diagnosis of exclusion. In particular, a child younger than the age of 10 years is much less likely to present with nonspecific back pain than an older child or adolescent. The same is true of muscular and ligamentous strains, which are common in adolescents but less likely in young children. Most authors recommend a minimum of plain x-rays, in addition to a thorough hx and physical examination, when evaluating children < 10 yrs.

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Emergent magnetic resonance imaging and neurosurgical evaluation are indicated when neurologic abnormalities indicate a spinal cord lesion or compression. Such findings are more likely in cases of spinal cord tumors (astrocytoma or ependymoma), disc herniation or spondylolisthesis with cord compression, or epidural abscess.

Lumbosacral radiographs, including oblique views, are the standard initial evaluation for an adolescent suspected of having spondylolysis. Spondylolysis represents a stress fracture through the pars interarticularis portion of the posterior elements. It presents most commonly in adolescents who have lower back pain that is exacerbated by activity, especially extension of the spine. Spondylolysis has been shown to occur more frequently in children and adolescents who participate in certain activities associated with repetitive hyperextension of the spine, such as gymnastics, diving, dance, football (especially linemen), rowing, and weightlifting. The most commonly involved vertebra is L5, followed by L4. Physical examination reveals focal lumbar tenderness, limited spinal range of motion, and exacerbation of pain with lateral bending (toward the side of unilateral lesions) and hyperextension of the spine. Approximately 80% of lesions are bilateral. Spondylolisthesis is the anterior slippage of the upper vertebra relative to the vertebra below, most commonly L5 on S1. This represents displacement of the anterior elements of a vertebra with bilateral pars interarticularis fractures. As the degree of slippage increases, nerve compression and neurologic signs and symptoms can occur. Spondylolysis and spondylolisthesis with less than 50% displacement are treated conservatively with rest, pain management, and thoracolumbosacral orthosis. Lesions that fail to improve with conservative management and those that have more than 50% displacement are treated surgically.

The use of nonsteroidal anti-inflammatory medications and rest is appropriate for back pain due to muscular or ligamentous strain.

SCFE:Chronic knee pain, external rotation of the hip joint at rest, and normal results of knee examination described for an obese adolescent is consistent with slipped capital femoral epiphysis (SCFE). Sometimes the chronic pain is exacerbated by acute trauma, and limited range of motion is another typical physical examination finding in SCFE. The most effective diagnostic evaluation for this condition is radiography of both hips in posteroanterior and frog-leg projections because subtle evidence of slippage on the contralateral side may be present in up to 25% of patients at presentation. The typical radiographic finding is described as “ice cream falling off the cone,” which is best appreciated on the frog-leg projection (Figure 1)

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Figure 1

 The use of Klein's line (a straight line drawn along the superior aspect of the femoral neck) in subtle cases may help to reveal the diagnosis. In the normal hip, the line should intersect the lateral capital epiphysis; in SCFE, capital femoral epiphysis is medial to this line (Figure 2). Once the diagnosis is confirmed, management should include nonweight-bearing status and immediate orthopedic referral for surgical stabilization.

Figure 2

SCFE is most common in adolescents and African Americans, particularly those who are obese. It is characterized by either acute or subacute displacement of the capital femoral epiphysis. Rapid growth at puberty, anatomic changes in the joints, and mechanical stressors on the joint are believed to contribute to the development of SCFE. Obesity can increase mechanical stress and physeal fatigue.

A complete blood count with manual differential count, erythrocyte sedimentation rate, and blood culture should be ordered when there is concern for septic arthritis, the presentation of which typically is acute. Septic arthritis usually is seen in younger children. Bone scan of the hip is useful for diagnosing subacute osteomyelitis, which is a less likely but plausible diagnosis if the plain radiographs do not document SCFE. Erythrocyte sedimentation rate is a nonspecific test for inflammation and may suggest rheumatologic, infectious, or oncologic processes. Ultrasonography also should be considered if plain radiographs show a widened joint space.

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Spine & Spinal Cord Trauma (ATLS Text)Must always be considered in a patient with multiple trauma

10% of patients with a c-spine fracture have a second, noncontiguous vertebral column fracture (“Look up and look down for injuries”)

5% of brain-injured patients have an associated spinal injury

25% of spinal injury patients have at least mild brain injury

55% of spinal injuries occur in the cervical region

15% of spinal injuries occur in the thoracic region

15% of spinal injuries occur at the thoracolumbar junction

15% of spinal injuries occur in the lumbosacral area

5% of patient experience new onset of neurologic symptoms or worsening of symptoms after reaching the ED—may be the result of failure to immobilize.

Note: as long as the spine is protected, its evaluation for injury may be safely deferred until after ABC issues are addressed (i.e. respiratory failure, hypotension, etc.)

Logroll patient every 2 hours to reduce decubitus ulcer risk if still immobilized

Spinal Cord Anatomy:There are many tracts but only 3 can be readily assessed clinically:

(1) Corticospinal (in posterolateral cord segment, controls ipsilateral motor function, tested by voluntary muscle contraction or involuntary response to painful stimuli)

(2) Spinothalamic (in anterolateral cord segment, transmits pain and temp from contralateral side, tested by pinprick and light touch)

(3) Posterior columns (carry position sense “proprioception”, vibration sense and some light touch from ipsilateral side of body, tested by position sense in the toes and fingers or by vibration sense using a tuning fork)

Each is a paired tract that may be injured on 1 or both sides of the cord. Injury patterns also relate to the area of the spinal cord that is affected. Simplistically, the anterior cord encompasses motor tracts, the exit of ventral motor fibers, and pain and temperature tracts. The posterior compartment contains dorsal columns (pain and proprioception) and sensory fibers.

Complete spinal cord injury: no demonstable sensory or motor function below a certain level (during first few days post injury, you can’t make this diagnosis with certainty due to possibility of spinal shock). Complete transection (Fig. 3) results in immediate and complete loss of function below the level of transection.

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Figure 3: Complete spinal cord transection

Incomplete spinal cord injury: if any motor or sensory function remain; better prognosis for recovery; Sacral sparing= preservation of some sensory perception in the perianal region and/or voluntary contraction of the rectal sphincter, may be the only sign of residual function

Sensory Level=the lowest dermatome with normal sensory function and can often differ on the 2 sides of the body; knowing key dermatomes is invaluable in determining the level of injury and assessing neurologic improvement or deterioration.

Dermatomes:C1-4 dermatomes are variable and are not used for localizationC5: deltoidC6: thumbC7: middle fingerC8: little fingerT4: nippleT8: xiphisternumT10: umbilicusT12: symphysis pubisL4: medial aspect of calfL5: web space between the first and second toesS1: lateral border of footS3: ischial tuberosity areaS4-5: perianal region

Motor Level=the lowest key muscle that has a grade of at least 3/5Myotomes:C5: deltoidC6: wrist extensorsC7: elbow extensorsC8: middle finger flexorsT1: small finger abductorsL2: hip flexorsL3-4: knee extensorL4-S1: knee flexionL5: ankle and big toe dorsiflexorsS1: ankle plantar flexors

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Grade each myotome (muscle strength) on a 0-5 scale:0: total paralysis1: palpable or visible contraction2: full range of motion with gravity eliminated3: full range of motion against gravity4: full range of motion but less than normal strength5: normal strength

Spinal cord injuries of C1-8 result in quadriplegiaSpinal cord injuries below T1 result in paraplegia

Neurogenic Shock vs. Spinal Shock:Neurogenic shock: results from impairment of the descending sympathetic pathways in the spinal cord; results in loss of vasomotor tone (causing vasodilation and hypotension) and sympathetic innervation to the heart (causing bradycardia or a failure to become tachycardic in the face of hypovolemia); characterized by hypotension and bradycardia. A diagnosis that should be entertained only after hemorrhagic shock has been excluded. Treat brady with Atropine and hypotension with alpha agonists (phenylephrine). Remember, patients with hypovolemic shock are usually tachycardic while those in neurogenic shock are classically bradycardic

Spinal shock: refers to flaccidity and loss of reflexes after spinal cord injury

Effect on other organ systems: (1) Hypoventilation: therefore, intubate patient prior to transfer if any possibility of theseUpper to middle cervical cord injuries paralyze the diaphragm (phrenic nerve source)Lower cervical to upper thoracic cord injuries paralyze intercostals muscles (2) Masking acute abdomen signs: if pain cannot be perceived in that area

Spinal Cord Syndromes:

Central cord syndrome (Fig 4) : good prognosisMotor loss in UE > LE; with varying degrees of sensory loss; seen after a hyperextension injury like a forward fall with facial impact; may occur with or without c-spine fracture; recovery follows a characteristic pattern of LE motor recovery first, then bladder function, then proximal UE, then hands last; it is due to vascular compromise of the cord in the anterior spinal artery distribution. This is a consequence of the configuration of the lateral corticospinal tract where cervical motor fibers lie medially and the thoracic, lumbar, and sacral fibers lie progressively more laterally. Fig 4: Central cord syndrome

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Anterior cord syndrome: poor prognosisInjury to the anterior compartment (Fig. 5) is more common, either through direct mass effect or disruption of the blood supply through the anterior spinal artery. Paraplegia and loss of pain and temperature sensation; posterior column function is preserved. The pattern of injury involves loss of motor function and pain sensation below the level of injury but preservation of touch sensation and proprioception.

Figure 5: Anterior cord syndrome

Brown-Sequard’s syndrome: moderate prognosisHemisection of cord; rarely seen; ipsilateral motor loss (lateral corticospinal tract) and ipsilateral loss of position sense (posterior column) with contralateral loss of pain and temperature (spinothalamic tract) beginning 1-2 levels below the level of injury; can be caused by direct penetrating injury to cord. (Fig. 6) Concussion of the cervical spinal cord refers to transient traumatic paralysis that may recover in hours or longer.

Figure 6: Brown-Sequard syndrome

Posterior Cord Syndrome: Finally, injury to the posterior region (Fig. 7) is the least common, resulting predictably in loss of proprioception and pain sensation.

Figure 7: Posterior cord syndrome

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IMPORTANT NOTE: all patients with radiographic evidence of injury AND/OR all those with neurologic deficits (SCIWORA) are considered to have an unstable spinal injury and should be immobilized until cleared by neurosurgery!

Steroid Treatment: For SCIWORA or non-penetrating spinal cord injury, within 3 hours of injury, child should receive 30mg/kg of methylprednisolone over 15 minutes; followed in 45 minutes by a 23 hour infusion of 5.4mg/kg/hr. If the patient is between 3-8 hours postinfusion, a 48 hour course is given.

C-Spine Injuries:

Decision instruments have been developed that permit clinicians to reduce the use of cervical spine radiography safely in adult and pediatric patients who have sustained blunt trauma. A prospective multicenter trial evaluated the NEXUS decision instrument for identifying patients who have suffered blunt trauma and in whom radiographs of the cervical spine should be obtained. Low-risk patients must meet all five NEXUS criteria, which include: 1) absence of midline cervical tenderness, 2) no evidence of intoxication, 3) normal level of alertness, 4) normal results on neurologic examination, and 5) absence of a painful or distracting injury. If a patient fulfills all five of the NEXUS criteria, plain radiographs are of marginal value.

In a subgroup analysis, none of the 603 children (from the total 3,065 children) designated as low-risk had evidence of cervical spine trauma on three-view plain radiography. The overall sensitivity of NEXUS in the pediatric population was reported as 100% (95% confidence interval, 88%, 99.6%). However, the validity of results in the younger age group has been questioned because only four of the 30 significant CSIs occurred in patients who were younger than 9 years of age and none were seen in children younger than 2 years. Therefore, the Congress of Neurologic Surgeons recommends application of NEXUS criteria for children older than 9 years of age.

The unique anatomy and biomechanics of the pediatric cervical spine help explain the different radiographic features, injury patterns, and management options found in children compared with those in adults. The principal difference is that the pediatric cervical spine is intrinsically more elastic compared with the adult spine, especially in the first 8 years after birth. Such elasticity is a result of several distinct features. First, the facet joints are shallower than in the adult spine and are oriented horizontally, which has the effect of increasing translational mobility and movement during flexion and extension. Second, spinal ligaments and joint capsules can withstand significant stretching without tearing, which contributes to the occurrence of pseudosubluxation. Third, several authors have argued that the anterior wedging of the vertebral bodies allows ventral slippage between motion segments, although others have noted that the wedging that appears on radiographs is due to a ring apophysis that does not ossify before the age of 12 years, making this a radiographic rather than an anatomic finding. Finally, weak nuchal muscles also lend more flexibility to the spine.

Another important feature in children younger than 8 years of age is the relatively large head compared with the body. The added weight shifts the fulcrum of movement to the

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upper cervical spine, with the greatest movement at C2-C3 in infants and young children. By 5 to 6 years of age, the fulcrum shifts to C3-C4, and in adolescents and young adults, the level of maximal flexion is C5-C6, the same as in mature adults. This disparity in the fulcrum of movement explains why most cervical spine injuries occur between the occiput and C2 in children younger than 9 years of age, but the distribution of cervical injuries in children older than 9 years is similar to that in adults, with fractures and fracture-dislocations predominantly occurring in the lower cervical spine.

A large head relative to the body has one other critical consequence, which is to force the cervical spine into kyphosis when a child is placed on a firm backboard. In the setting of trauma, this may exacerbate a traumatic kyphotic deformity and compromise neurologic function. Semirigid cervical collars are not adequate to prevent flexion and, therefore, the torso must be raised or a recess for the occiput provided. In a recent prospective cohort study of 76 Australian children, standard immobilization combined with thoracic elevation of the shoulders in children aged 10 years and younger who had suspected CSI was effective in placing the cervical spine in neutral position. All patients required torso elevation (mean elevation, 25 mm) to rest the neck in a neutral position. Children younger than 4 years may require more elevation. The goal of elevation should be to align the patient’s external auditory meatus with the shoulders, a position that eliminates flexion. Alternatively, an occipital recess can correct misalignment.

Another pitfall during immobilization at the scene is the unintended consequence of straps that may be too tight on the torso. This may lead to decreased vital capacity, particularly in a young child who may have pre-existing hypoventilation from a traumatic brain injury. Similarly, a patient who has high cord injury can sustain a phrenic nerve injury with paradoxic respirations that may be exacerbated by tight chest restraints.

The fulcrum of cervical motion occurs at the C5-C6 level in adolescents/adults but it occurs at the C2-C3 level in children (due to the relatively larger mass of the child’s head). Thus, the majority of spinal injuries in children involve the upper cervical spine and the cranio-vertebral junction. Associated mortality is higher in children.

Compared to adults, children have much more laxity in their spinal ligaments, weaker musculature, and more horizontally angled facet joints. Therefore, children can have significant spinal cord injuries without spinal fractures. This injury is referred to as a spinal cord injury without radiographic abnormality (SCIWORA).

There is a normal “pseudosubluxation” of C2 on C3 or C3 on C4 of up to 4 mm that occurs in 40% of children up to age 7. A line drawn between the anterior cortices of the spinous processes of C1 and C3 (line of Swischuk) should intersect or be less than 2 mm from the anterior cortex of the spinous process of C2; otherwise a pathologic subluxation should be considered.

Jefferson (Burst) Fracture: seen in axial compression injuries (i.e. diving); involves fractures through the anterior and posterior arches of C1 (the atlas).

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Hangman’s Fracture: the typical axis (C2) fracture, involves bilateral fractures of the pars interarticularis and anterior subluxation of C2 on C3.

Patellar Dislocation:Patellar dislocation can occur at any age but is most frequent in adolescence in association with competitive sports (especially football, basketball, and soccer). With acute traumatic dislocation, there is failure of at least one medial structure, most often the medial patellofemoral ligament. Alternatively, there may be a fracture at the medial chondro-osseus junction. Associated injuries may include osteochondral fracture of the lateral femoral condyle or patella.

Children who have a patella dislocation usually present with acute pain and swelling after knee trauma. The knee is held in a slightly flexed position, and the patella often is recognized easily to be displaced laterally. If the child has a history of prior patella dislocation, the injury often reduces spontaneously after the event. If there is no suspicion of associated fracture, patella relocation can be achieved in the emergency department, by flexing the hip slightly to relax the quadriceps muscles and then gently extending the knee while applying mild medial pressure to the lateral aspect of the patella until it pops back into place. After reduction, the child should be placed in a knee immobilizer or cylindrical leg cast to allow time for the ligaments to heal. Follow-up with an orthopedic specialist should be arranged.

Risk factors associated with patellar dislocation are patella alta (high-riding patella in relation to the femur), genu valgum (knock knees) rather than genu varus, increased femoral anteversion, and overall ligamentous laxity. A high-riding patella alters patellofemoral mechanics and alignment, predisposing to subluxation. Genu valgum and increased femoral anteversion (with concomitant internal tibial torsion) predispose to patellar subluxation by increasing the Q angle. The Q angle is formed by the intersection of a line drawn from the anterior superior iliac spine to the central patella and from the central patella to the tibial tubercle. Septic Hip:In the true anteroposterior view of the hip, the distance between the head of the femur and the inferior tip of the acetabulum is significantly wider on the affected side. Such widening of the joint space is indicative of increased fluid in the joint space and, in the setting of fever and irritability, is pathognomonic for septic arthritis of the hip. Ultrasonographically guided arthrocentesis with immediate orthopedic consultation to expedite time to operative debridement of the hip is imperative. In an institution that does not have 24-hour ultrasonography availability, arthrocentesis should be performed under fluoroscopy.

Serum blood tests may be helpful in diagnosing septic arthritis. However, although the peripheral white blood cell count is often elevated in children with septic arthritis, as many as 20% of children have normal values. Furthermore, although the erythrocyte sedimentation rate and C-reactive protein values frequently are elevated, they are nonspecific findings. Osteomyelitis not complicated by septic arthritis is not characterized by widening of the joint space. If the osteomyelitis has been present for 5 to

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7 days, radiography may reveal a bony lytic lesion.

If the diagnosis of septic hip is confirmed with arthrocentesis (joint fluid shows elevated white blood cell count, usually >50.0x103/mcL [50.0x109/L], as well as a low glucose concentration [usually about 30% of the serum value] and a positive Gram stain), the child should be taken to the operating room emergently. Gram stain is only positive in 75% of cases, and cultures are positive in 60%.

Group B Streptococcus and Staphylococcus aureus are the primary pathogens causing septic arthritis in the neonatal age group, with rare gram-negative infections documented. Haemophilus influenzae type b, a previously common pathogen, has been eradicated in the vaccinated population, although under- or unimmunized infants remain at risk. In older infants and toddlers, S aureus is the single most common pathogen; group A streptococci are seen less frequently. Kingella kingae, a gram-negative coccobacillus, is being recognized increasingly as a pathogen in older infants and toddlers due to improved detection techniques. Kingella is a fastidious organism that frequently is missed on routine culture. Inoculation of commercial blood culture bottles with synovial fluid may increase the yield on the culture and is recommended by many infectious disease experts. Among teenagers, most studies demonstrate that Neisseria gonorrhoeae is slightly more prevalent than S aureus. Children who have sickle cell anemia are at risk for Salmonella infections, in addition to the typical pathogens seen in their age group.

If septic arthritis is suspected for any patient on the basis of historical features (atraumatic limp or restriction of motion of the joint) and physical examination findings (pain with passive or active range of motion of the joint, swelling, warmth, and elevated inflammatory markers), arthrocentesis should be performed. Notably, joint warmth and swelling cannot be appreciated in bacterial infection of the hip. In addition, normal findings on radiography do not exclude the diagnosis. When clinical suspicion is high, additional imaging such as ultrasonography or proceeding to arthrocentesis is warranted.

Septic arthritis usually is caused by hematogenous spread and rarely by direct inoculation of the joint.

Transient Synovitis:Transient synovitis is a more common cause of acute hip pain or limp, especially in older children (3 to 10 years of age). There is often a history of a recent upper respiratory tract infection. The child is usually appears well and is afebrile or has a low-grade fever. The hip may be held in flexion with slight abduction and external rotation, similar to the presentation of a septic hip; however, there is only mild, if any, limitation in movement. A number of clinical prediction rules have been developed to help differentiate transient synovitis of the hip from septic arthritis in toddlers and children. None has been validated by a multicenter prospective study involving large numbers of patients. The prediction rules published to date have been summarized by Taekema and associates, who conclude that although no one investigation or blood test can reliably distinguish transient synovitis from septic arthritis, some combination of fever, nonweight bearing, C-reactive protein greater than 20 mg/L (2 mg/dL), erythrocyte sedimentation rate greater than 40 mm/h,

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and white blood cell counter greater than 12.0x103/mcL (12.0x109/L) is highly suspicious for septic arthritis.

Miscellaneous:Risk factors associated with patellar dislocation are patella alta (high-riding patella in relation to the femur), genu valgum (knock knees) rather than genu varus, increased femoral anteversion, and overall ligamentous laxity

In compartment syndrome, you get pain, paresthesias, and decreased pulses—pallor and paralysis come late. Next step is to measure compartment pressures and consult ortho for fasciotomy.

In the normal lateral elbow x-ray, the anterior humeral line should intersect the capitellum in its middle third, and also intersect the middle to posterior third of the olecranon. Posterior displacement of the distal humerus is common with supracondylar fractures, and results in the anterior humeral line intersecting at a point anteriorly. In a normal lateral x-ray of the elbow, the line drawn along the axis of the radius should also pass through the center of the capitellum.

With an anterior shoulder dislocation, the axillary nerve can be damaged which would cause decreased sensation over the lateral deltoid muscles.

Staph epidermidus followed by gram negatives then staph aureus are the most common causes of shunt infections.

A triplane fracture is a combination of a Salter-Harris type II and type III fractures of the distal tibia. These are unstable fractures and should be seen in the ED by Ortho; the next step would be an ankle CT.

For patients with unstable pelvic fractures, disruption of the pelvic veins can result in life-threatening hemorrhage. A flexible external compression device should be immediately applied.

A patient with a posterior dislocation of the clavicle at the sterno-clavicular joint who is stable without respiratory compromise should be evaluated by CT, which will show not only the dislocation but also any impingement on the trachea or great vessels. In patients with acute respiratory compromise, immediate ortho reduction by open or closed technique would be indicated prior to the CT scan.

In patients with mediastinal masses due to ALL or lymphoma, if they need to be intubated, they are at risk for sudden cardiorespiratory collapse. Complete airway obstruction from tracheal compression or obstruction of ventricular outflow are thought to be mechanisms that may occur when the dynamics of intrathoracic pressure are altered during sedation. If RSI is required, it should be done in the OR by an anesthesiologist and surgeon using a rigid laryngo-bronchoscope.

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A Ewing’s Sarcoma of the chest wall typically involves the lateral aspect of the ribs and presents as a hard, tender lump on the chest wall. The next step in the evaluation would be a chest CT.

70% of V-P shunt infections occur within 2 months of surgery.

For sickle cell disease patients with a CVA, the treatment is a simple or partial exchange transfusion.

Bradycardia is usually the earliest and most sensitive indicator in Cushing’s triad, which is bradycardia, hypertension, and irregular respirations associated with increased ICP.

Impairment of CSF resorption at the interface with the venous circulation is termed communicating hydrocephalus. Impairment of CSF flow through the ventricular system or subarachnoid spaces is termed obstructive hydrocephalus.

90% of shunt infections are diagnosed within 6 months of shunt placement/revision.

AV malformation is the most common cause of hemorrhagic stroke in childhood beyond the neonatal period. Small AVM’s have a greater risk of hemorrhage than large ones.

Brain tumors are the most common solid tumors of childhood. Only leukemia is more common than brain tumors. 50% of pediatric brain tumors are astrocytomas.

Elbow Dislocation:

The peak incidence of this injury occurs in adolescents between 11-15 years. Posterior and posteriolateral dislocations of the forearm (ulna) are most common types (95%). The usual mechanism of injury is a fall on outstretched hand with the forearm supinated, in contrast to supracondylar fractures of the distal humerus, in which the forearm typically is pronated. Physical examination reveals an obvious deformity of the elbow, with prominence of the olecranon process. There may be associated neurovascular compromise, similar to injuries to the distal humerus. Associated injuries in decreasing order of frequency include:

• Avulsion fracture of the medial epicondyle (most common), with entrapment of the medial epicondyle (a possible complication of reduction that requires open reduction)

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• Coronoid process fracture• Radial neck fracture• Injury to brachial vessels or ulnar and median nerves• Intra-articular entrapment of median nerve following close reduction of elbow

dislocations in childrenUnder procedural sedation or general anesthesia, the physician encircles the patient’s upper arm with his or her hands, at the same time pushing the olecranon downward and anteriorly with the thumbs. Avoid hyperextension of the elbow, which may stress the neurovasculature further. After successful reduction, the pulse, sensory, and motor functions of the forearm should be evaluated. Operative management, including open reduction, should be undertaken if there is residual deficit. Postreduction films should be examined carefully for evidence of bony injuries that were obscured on the initial radiographs. In addition, the joint should be immobilized. Due to swelling and potential development of compartment syndrome, inpatient observation may be warranted. 

The initial emergency department treatment priorities for children who suffer blunt trauma to the brain are to prevent secondary brain injury and stabilize the patient for further diagnosis and treatment. The goal is to preserve perfusion and oxygenation of the viable regions of the brain while preventing the mass effects that lead to ongoing injuries and herniation. For the boy described in the vignette, who has suffered a major head injury, the presence of bradycardia and systemic hypertension indicate impending cerebral herniation. To that end, one priority is to preserve cerebral blood flow by maintaining cerebral perfusion pressure (CPP = mean arterial pressure [MAP] – intracranial pressure [ICP]). This goal must be balanced against possible progression of the underlying injury. Emergency treatment that quickly lowers ICP, such as hyperventilation or administration of mannitol, usually leads to decreased CPP, compromising perfusion to viable tissues. However, such action is necessary in cases of impending herniation.

Relative hypocarbia (Pco2 ~35 mm Hg) is potentially protective and,

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when induced by hyperventilation in the setting of acute head trauma with impending cerebral herniation, may be life-saving. Thus, hypocarbia is used to preserve cerebral perfusion, not to decrease it. Neuronal damage as a result of the primary injury is not reversible. Hypoglycemia is rare in cases of head injuries; hyperglycemia is more common and is potentially damaging.

Several approaches to preventing or reducing brain trauma have been suggested. Mannitol (0.25 to 1.0 g/kg)is indicated in cases of refractory intracranial hypertension or signs and symptoms of impending herniation, although there is no empiric evidence of its efficacy in pediatric populations.  

A randomized study showed that the treatment of severe traumatic brain injury with 3% saline was superior to lactated Ringer solution in children. In this study, children treated with hypertonic saline required fewer interventions, had fewer complications, and had shorter stays in the intensive care unit. Doses commonly used are between 0.1 and 1 mL/kg per hour. A recent large trial involving mostly adult patients, however, showed no benefits in neurologic recovery with early hypertonic saline treatment.

Approximately 20% to 30% of children who have moderate-to-severe brain injury develop early posttraumatic seizures, occurring within 7 days of injury. Thus, prophylactic anticonvulsants, such as fosphenytoin, may reduce the incidence of seizure in the first week after injury but not thereafter.  

Finally, despite promising animal models, no benefits were seen for hypothermia in children who had severe head injuries in a relatively large randomized, controlled trial.

Head Injuries:

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Table 2: Recommendations for Acute Management of Severe Traumatic Brain Injury

Recommendations

Blood glucose • Maintain <200 to 250 mg/dL (11.1 to 13.9 mmol/L)

Temperature • Avoid hyperthermia• Cool patients to 36.0 to 37.0°C• Consider hypothermia (32.0 to 34.0°C) for refractory elevated ICP

CBF and Paco2 • Consider brief periods of mild hyperventilation for impending herniation

Systolic blood pressure

• Correct hypovolemia rapidly• Maintain systolic blood pressure >5th percentile for age (may be

beneficial to maintain systolic blood pressure >50th percentile)

CPP (MAP-ICP) • Elevate head of bed to 30 degrees and maintain patient head position in midline

• Maintain >40 mm HgICP • Consider mannitol 0.25 to 1 g/kg

• Consider 3% hypertonic saline 0.1 to 1 mL/kg per hourSeizures • Consider prophylactic anticonvulsant

CBF=cerebral blood flow, CPP=cerebral perfusion pressure, ICP=intracranial pressure, MAP=mean arterial pressure

Data from Sookplung P, Vavilala MS. What is new in pediatric traumatic brain injury? Curr Opin Anaesthesiol. 2009;22:572-578.

The boy described in the vignette has sustained severe blunt head trauma and has clinical and radiologic signs of elevated intracranial pressure (ICP). His vital signs suggest that he is in uncompensated shock. The relative bradycardia, pupillary asymmetry, and extensor posturing suggest acute brainstem herniation. The CT scan shows a large subdural hemorrhage with midline shift and effacement of the cisterns.

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The immediate management priority for this boy is to institute measures to maintain cerebral perfusion pressure, decrease ICP, and prevent secondary brain injury. This can be achieved best by correction of hypotension with an intravenous isotonic fluid bolus and hyperventilation. Appropriate fluid resuscitation involves administration of 20 mL/kg of normal saline or lactated Ringer solution. Although administration of mannitol may be an appropriate intervention for patients demonstrating signs of acute brainstem herniation, such an osmotic diuretic in this case would exacerbate hypovolemia and hypotension, leading to secondary brain injury. Patients who have severe traumatic brain injury (TBI) are also at risk for posttraumatic seizures. Empiric evidence suggests that administering prophylactic anticonvulsants may prevent seizures in the first week after injury in high-risk patients.                                                                                   

A classification scheme for TBI is presented in Table 1. A summary of the mechanisms leading to elevated ICP following blunt head trauma are summarized in Figure 2.

Children have a higher incidence of elevated ICP following TBI than adults. Diffuse TBI is the most common type of injury, resulting in a range of injury severity from concussion to diffuse axonal injury (DAI). Patients who have DAI may have normal-appearing cranial CT scans when they are obtained early after sustaining the injury. Young infants are also vulnerable to inflicted injury; most inflicted injury-related deaths involve TBI. Patients who have suffered abusive head trauma commonly present with altered mentation, coma, seizures, emesis, or irritability. A history of the mechanism of injury is often lacking or injuries may be out of proportion to the history or developmental milestones. The injury pattern includes subdural hemorrhage, subarachnoid hemorrhage, skull fractures, or DAI with or without cerebral edema. The outcome after inflicted TBI is typically poor.

For epidural hematoma, the classic sequence of events after sustaining a head injury is an initial loss of consciousness, followed by a lucid interval, followed once again by an alteration in the level of consciousness. This classic presentation occurs in less than one third of the cases; in other cases there may be no history of loss of consciousness or persistent loss of consciousness from the time of the injury. The rapid increase in ICP is a result of arterial bleeding, most commonly the middle meningeal artery from injuries around the temporal region. Prompt recognition of the injury is critical to providing appropriate medical or surgical intervention. A subdural hematoma results from bleeding from bridging veins or dura and can lead to increased ICP, as seen with epidural hematomas. Deterioration

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generally is not as rapid as with an epidural hematoma and may occur hours to days after the initial injury. A cerebral contusion represents direct injury to the brain parenchyma and can be seen with CT scan. Subarachnoid hemorrhage is common with severe brain injury and leads to blood in the cerebrospinal fluid. A concussion is a head injury that causes at least temporary neurologic dysfunction, often with loss of consciousness of 1 minute or less. These injuries may be associated with abnormal findings on postinjury magnetic resonance imaging, although a cranial CT scan usually appears normal.

A summary of the therapeutic recommendations for management of TBI are shown in Table 2. The goal is to prevent secondary insults to the brain such as hypoxia, hyperglycemia, hyperthermia, hypotension, and increasing ICP, all of which can worsen outcome.

Patients who have signs of increased ICP may benefit from temporary hyperventilation. The resulting hypocarbia causes reflex cerebral vasoconstriction that, in turn, reduces the volume of the intracranial vasculature and, thus, the ICP. However, excessive or prolonged (>1 to 2 hours) hyperventilation may lead to excess vasoconstriction and decreased cerebral blood flow, so hyperventilation should be used cautiously. The target Pco2 should be approximately 35 mm Hg to achieve the optimal balance between ICP and cerebral blood flow.

Mannitol at a dose of 0.25 to 1 g/kg also is used to reduce ICP, especially if there are clinical signs of impending herniation, such as dilated pupils. The high osmolarity of mannitol draws free water into the vasculature, leading to a decrease in blood viscosity and improved cerebral blood flow. The improvement in cerebral oxygenation then leads to reflex vasoconstriction and lower ICP. Mannitol also must be used with caution because its action as a diuretic may exacerbate hypovolemia and systemic hypotension. Volume expansion with 20 mL/kg normal saline is indicated if there is significant hypotension. Hypotonic fluids or glucose-containing solutions should be avoided because they can harm the injured brain. Many of these steps are taken simultaneously in the typical trauma patient.

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