# Seminar 04: Trauma Emergencies ## Year 3: Emergency Medicine Clerkship --- ## Learning Objectives By the end of this seminar, students will be able to: 1. Apply ATLS principles to trauma resuscitation 2. Perform primary and secondary trauma surveys 3. Manage traumatic hemorrhage and shock 4. Evaluate and stabilize head and spinal injuries 5. Recognize and treat thoracic and abdominal trauma 6. Coordinate multidisciplinary trauma care --- ## Seminar Outline ### I. Trauma Systems and Triage Trauma systems organize prehospital and hospital resources to optimize care for injured patients through regionalization that matches patient needs with facility capabilities. Level I trauma centers provide comprehensive care including twenty-four-hour in-house surgical coverage, all specialty services, and research and teaching missions that develop trauma expertise. Level II centers offer comprehensive care similar to Level I but may lack research requirements and transfer complex cases exceeding local capabilities. Level III and IV centers focus on stabilization and appropriate triage to higher-level facilities when injury severity exceeds local resources. This hierarchical system ensures that severely injured patients reach definitive care within the golden hour while avoiding overwhelming specialized centers with minor injuries manageable at community hospitals. Trauma activation criteria trigger rapid assembly of the trauma team based on physiologic derangement, anatomic injury patterns, and mechanism of injury suggesting high-energy transfer. Physiologic criteria representing active instability include Glasgow Coma Scale below fourteen suggesting neurologic injury, systolic blood pressure below ninety indicating hemorrhagic shock, respiratory rate below ten or above twenty-nine signaling respiratory compromise, and need for airway intervention. Anatomic criteria reflecting severe injury patterns include penetrating injuries to head, neck, or torso, flail chest, two or more proximal long bone fractures, crushed or degloved extremities, amputation proximal to wrist or ankle, pelvic fractures, and paralysis suggesting spinal cord injury. These criteria identify patients requiring immediate team response rather than routine evaluation. Mechanism criteria identify patients at risk for occult severe injury based on energy transfer characteristics even when initial assessment appears reassuring. Falls greater than twenty feet in adults or ten feet in children involve significant kinetic energy dissipation at impact. Motor vehicle crashes with intrusion greater than twelve inches at occupant site, ejection from vehicle, or death of another occupant in the same vehicle indicate high-energy mechanisms. Motorcycle crashes at speeds exceeding twenty miles per hour, auto-pedestrian or auto-cyclist impacts with significant speed, and pedestrians thrown or run over warrant heightened concern. These mechanism criteria lower the threshold for full trauma team activation even when physiologic and anatomic criteria are not met on initial evaluation. Trauma team organization assigns specific roles enabling parallel task completion during the chaotic initial resuscitation period. The team leader maintains situational awareness, coordinates care, makes key decisions, and communicates with consultants without becoming absorbed in procedures. Dedicated airway and procedural providers perform necessary interventions while primary survey personnel conduct systematic assessment and relay findings. The recorder documents interventions, times, and findings in real-time, creating essential records for ongoing care and quality review. Nursing team members establish access, administer medications, draw laboratory samples, and monitor vital signs. Surgical consultation occurs early for patients likely to require operative intervention, enabling preparation for direct emergency department to operating room transport. Panel A: Trauma center levels showing capabilities from comprehensive Level I through stabilization-focused Level IV with transfer patterns. Panel B: Physiologic activation criteria including GCS, blood pressure, respiratory rate, and airway needs with threshold values. Panel C: Anatomic activation criteria depicting penetrating injuries, skeletal injuries, and amputation patterns triggering team response. Panel D: Trauma team role assignments showing team leader, airway, procedure, recorder, nursing, and surgical consultant positions. --- ### II. Primary Survey (ABCDE) Airway assessment with cervical spine protection constitutes the first priority because hypoxia kills quickly and airway compromise prevents all other therapeutic interventions from succeeding. In trauma patients, the cervical spine must be assumed injured until proven otherwise, requiring inline stabilization during all airway maneuvers rather than the head-tilt chin-lift used in non-trauma settings. The jaw thrust maneuver opens the airway while maintaining cervical alignment. Rapid sequence intubation with manual inline stabilization by a dedicated team member represents the standard approach when definitive airway is required, with surgical cricothyrotomy immediately available for cannot-intubate situations. A rigid cervical collar maintains alignment during transport and between interventions but must be removed for airway procedures with manual stabilization substituted. Breathing assessment identifies immediately life-threatening thoracic injuries requiring intervention during the primary survey before progression to circulation assessment. Inspection reveals asymmetric chest rise, paradoxical motion of flail segments, and open chest wounds. Auscultation identifies absent breath sounds suggesting pneumothorax or hemothorax. Percussion hyperresonance with absent breath sounds indicates pneumothorax, while dullness suggests hemothorax. Tracheal deviation, distended neck veins, and hypotension with absent breath sounds constitute the tension pneumothorax triad requiring immediate needle decompression without waiting for imaging. Open pneumothorax from a sucking chest wound requires three-sided occlusive dressing to allow air egress during expiration while preventing entrainment during inspiration, followed by tube thoracostomy. Circulation assessment focuses on identifying hemorrhagic shock and controlling bleeding to maintain perfusion of vital organs. Assessment includes pulse rate and quality, blood pressure, capillary refill, skin color and temperature, and mental status as a reflection of cerebral perfusion. External hemorrhage requires immediate direct pressure or tourniquet application for extremity wounds with arterial bleeding. Intravenous access with two large-bore peripheral catheters enables rapid volume administration, with intraosseous access as backup when peripheral access fails. Blood product resuscitation using packed red cells and fresh frozen plasma has largely replaced crystalloid-first approaches based on damage control resuscitation principles demonstrating improved survival with early blood product administration. Disability assessment evaluates neurologic status to identify brain injury requiring neuroprotective strategies or emergent intervention. The Glasgow Coma Scale provides standardized assessment combining eye opening, verbal response, and motor response scores. Pupillary examination identifies unilateral dilation suggesting uncal herniation with ipsilateral third nerve compression, demanding immediate intervention with osmotic therapy and hyperventilation while arranging emergent imaging and neurosurgical consultation. Gross motor assessment of all extremities identifies lateralizing weakness or spinal cord injury patterns. Point-of-care glucose excludes hypoglycemia as a cause of altered consciousness. Exposure ensures complete undressing for thorough examination while hypothermia prevention with warm blankets and warm intravenous fluids prevents the lethal triad of hypothermia, acidosis, and coagulopathy that drives mortality in severe trauma. Panel A: Airway assessment with cervical spine protection showing jaw thrust technique and inline stabilization during intubation. Panel B: Life-threatening thoracic injuries including tension pneumothorax, open pneumothorax, massive hemothorax, flail chest, and tamponade with immediate interventions. Panel C: Circulation assessment showing hemorrhage control with tourniquet, large-bore access establishment, and blood product resuscitation initiation. Panel D: Disability assessment demonstrating GCS components, pupillary examination, motor assessment, and hypothermia prevention measures. --- ### III. Hemorrhagic Shock Hemorrhagic shock classification guides resuscitation intensity based on estimated blood loss and physiologic response, though clinical assessment often underestimates severity due to compensatory mechanisms. Class I shock with less than fifteen percent blood volume loss typically produces minimal symptoms and normal vital signs, requiring volume replacement but not blood transfusion. Class II shock with fifteen to thirty percent loss causes tachycardia and anxiety with maintained blood pressure through compensatory vasoconstriction. Class III shock with thirty to forty percent loss overwhelms compensation, producing tachycardia above one hundred twenty, hypotension, and confusion requiring aggressive resuscitation with blood products. Class IV shock with greater than forty percent loss causes profound hypotension, minimal urine output, and obtundation with mortality rates exceeding fifty percent despite aggressive intervention. Damage control resuscitation principles have transformed trauma resuscitation through recognition that traditional aggressive crystalloid administration worsens outcomes through dilutional coagulopathy, hypothermia, and acidosis. Permissive hypotension targeting systolic blood pressure of eighty to ninety millimeters of mercury in penetrating trauma reduces ongoing hemorrhage while maintaining minimal perfusion, though this approach is contraindicated in traumatic brain injury where cerebral perfusion pressure must be maintained. Balanced resuscitation using packed red blood cells, fresh frozen plasma, and platelets in a one-to-one-to-one ratio approximates whole blood replacement and provides clotting factors along with oxygen-carrying capacity. Crystalloid administration is minimized because large volumes dilute clotting factors and reduce hematocrit without replacing lost blood components. Massive transfusion protocol activation provides systematic delivery of blood products at predetermined intervals, ensuring immediate availability without individual component ordering delays. Typical protocols deliver cooler packs containing packed red cells, fresh frozen plasma, and platelets in balanced ratios at fifteen to thirty minute intervals while hemorrhage control proceeds. Tranexamic acid administered within three hours of injury reduces mortality in bleeding trauma patients by inhibiting fibrinolysis, with dosing of one gram over ten minutes followed by one gram infused over eight hours. Calcium supplementation addresses hypocalcemia from citrate anticoagulant in blood products that binds ionized calcium. Fibrinogen replacement through cryoprecipitate or fibrinogen concentrate maintains coagulation when levels fall below one hundred fifty to two hundred milligrams per deciliter. Hemorrhage control strategies vary by anatomic source, with external bleeding addressed through direct pressure and tourniquets while internal hemorrhage requires procedural or operative intervention. Extremity hemorrhage responds to direct pressure; failing this, tourniquet application two to three inches proximal to the wound stops arterial inflow despite risk of ischemic injury with prolonged application. Chest hemorrhage requires tube thoracostomy for drainage and monitoring, with operative thoracotomy indicated for initial output exceeding fifteen hundred milliliters or ongoing output exceeding two hundred milliliters per hour. Abdominal hemorrhage from solid organ injury may be managed non-operatively in stable patients but requires laparotomy when hemodynamic instability persists. Pelvic hemorrhage from fractures involves venous, arterial, and bone surface sources, addressed through pelvic binding for mechanical stabilization along with angiographic embolization or preperitoneal packing for ongoing arterial bleeding. Panel A: Hemorrhagic shock classification showing blood loss percentage, vital sign changes, and clinical symptoms by class I through IV. Panel B: Damage control resuscitation principles including permissive hypotension, balanced one-to-one-to-one transfusion, and crystalloid limitation. Panel C: Massive transfusion protocol components with blood product ratios, TXA timing, and calcium supplementation. Panel D: Hemorrhage control by anatomic source showing tourniquet for extremity, tube thoracostomy for chest, and pelvic binder for pelvic hemorrhage. --- ### IV. Head Trauma Traumatic brain injury severity classification based on Glasgow Coma Scale score guides management intensity and predicts outcomes, with severe injury carrying substantial mortality and disability risk. Mild traumatic brain injury with GCS thirteen to fifteen represents the majority of head trauma presentations, typically managed with observation and discharge with return precautions when CT imaging excludes significant intracranial pathology. Moderate TBI with GCS nine to twelve requires hospital admission, repeated neurological assessment, and neurosurgical consultation for progression or mass lesions requiring intervention. Severe TBI with GCS eight or below demands airway protection through intubation, intensive care admission, intracranial pressure monitoring in many cases, and aggressive neuroprotective strategies to prevent secondary brain injury. Intracranial injury patterns carry different prognostic and management implications based on bleeding source, location, and mass effect. Epidural hematoma from middle meningeal artery injury classically presents with loss of consciousness, lucid interval, and subsequent deterioration, appearing as lens-shaped hyperdensity on CT, and frequently requires emergent operative evacuation. Subdural hematoma from bridging vein rupture presents as crescent-shaped hyperdensity following brain contour, occurring more commonly in elderly patients and those on anticoagulation, with surgical indication based on size, midline shift, and clinical status. Subarachnoid hemorrhage in trauma results from surface vessel injury rather than aneurysm rupture, appearing as blood in sulci and basal cisterns. Diffuse axonal injury from rotational acceleration forces may show minimal CT abnormality despite severe clinical impairment, with diagnosis supported by MRI findings. Secondary brain injury prevention constitutes the cornerstone of TBI management because primary injury at impact cannot be reversed but secondary injury from hypoxia, hypotension, and elevated intracranial pressure can be prevented. Hypoxia must be avoided through early airway protection and maintenance of oxygen saturation above ninety percent. Hypotension, defined as systolic blood pressure below ninety, dramatically worsens TBI outcomes and requires aggressive treatment to maintain cerebral perfusion pressure. Elevated intracranial pressure reduces cerebral perfusion and causes herniation; treatment includes head elevation to thirty degrees, osmotic therapy with mannitol or hypertonic saline, controlled hyperventilation as a temporizing measure, and surgical decompression for refractory elevation. Herniation syndromes represent neurological emergencies requiring immediate intervention to prevent brainstem compression and death. Uncal herniation from temporal lobe mass effect compresses the ipsilateral third cranial nerve, producing a fixed dilated pupil ipsilateral to the lesion, followed by contralateral motor posturing as the cerebral peduncle is compressed. Cushing's triad of hypertension, bradycardia, and irregular respirations indicates severely elevated intracranial pressure with brainstem compression. Emergency management includes immediate osmotic therapy with mannitol one gram per kilogram or hypertonic saline twenty-three point four percent thirty milliliters, brief hyperventilation to PCO2 of thirty to thirty-five to reduce cerebral blood volume, head elevation, and emergent neurosurgical consultation for decompression. These measures temporize while definitive management is arranged. Panel A: TBI severity classification by GCS score showing mild, moderate, and severe categories with management implications. Panel B: Intracranial injury patterns on CT demonstrating epidural lens shape, subdural crescent, subarachnoid blood in sulci, and diffuse axonal injury. Panel C: Secondary brain injury prevention targeting hypoxia, hypotension, and intracranial pressure with specific intervention thresholds. Panel D: Herniation syndrome recognition showing pupillary dilation, Cushing's triad, and emergency treatment protocol. --- ### V. Spinal Cord Injury Cervical spine immobilization in trauma reflects the potentially devastating consequences of spinal cord injury from unstable fractures that may be present without obvious external signs. All patients with significant blunt trauma mechanism should be immobilized until the cervical spine can be cleared clinically or radiographically. Rigid cervical collar application occurs prehospital and maintains alignment during transport and resuscitation. The collar must be removed during airway procedures with manual inline stabilization substituted to prevent cord injury from manipulation of an unstable spine. Full spinal precautions including log-roll technique for repositioning continue until thoracolumbar spine clearance as well, as isolated thoracolumbar injuries can occur and contiguous injuries exist in a significant minority of patients with cervical injury. Clinical clearance protocols enable collar removal without imaging in low-risk patients, reducing radiation exposure, delays, and unnecessary imaging costs. The NEXUS criteria permit clinical clearance when all five criteria are met: absence of midline tenderness, no focal neurological deficit, normal alertness without intoxication, and no distracting painful injury. The Canadian C-spine Rule provides a more nuanced approach incorporating mechanism risk factors, with low-risk patients able to rotate their neck forty-five degrees without pain cleared clinically. Patients not meeting clearance criteria require imaging, with CT having replaced plain radiography as the initial imaging modality due to superior sensitivity for fractures. MRI provides soft tissue assessment including ligamentous injury and cord signal abnormality when CT findings or neurological examination raises concern. Spinal cord injury syndromes reflect the anatomic organization of motor and sensory tracts within the cord, with patterns suggesting specific injury mechanisms and locations. Complete cord injury produces total absence of motor and sensory function below the injury level, carrying poor prognosis for functional recovery. Central cord syndrome, typically from hyperextension in patients with cervical stenosis, produces greater upper than lower extremity weakness with bladder dysfunction, carrying relatively favorable prognosis. Anterior cord syndrome from flexion injury or anterior spinal artery occlusion produces motor paralysis with pain and temperature sensation loss but preserved proprioception and vibration. Brown-Sequard syndrome from hemisection causes ipsilateral motor weakness and proprioception loss with contralateral pain and temperature sensation loss. Cauda equina syndrome from lumbosacral injury produces saddle anesthesia, bladder and bowel dysfunction, and variable lower extremity weakness. Spinal cord injury management focuses on preventing secondary injury through hemodynamic support, imaging for surgical planning, and early specialty consultation. Mean arterial pressure goals of eighty-five millimeters of mercury or higher for the first seven days may improve spinal cord perfusion, though evidence remains limited and vasopressor requirements create their own risks. Glucocorticoid administration, formerly routine, is no longer recommended based on studies failing to demonstrate benefit while documenting increased complications. Imaging with CT identifies fracture pattern and bony alignment, while MRI assesses cord compression and signal abnormality indicating edema or hemorrhage. Neurosurgical or orthopedic spine consultation determines whether operative stabilization or decompression is indicated based on instability patterns and cord compression. Panel A: Cervical spine immobilization showing collar application, inline stabilization during airway procedures, and log-roll technique. Panel B: Clinical clearance criteria comparing NEXUS criteria and Canadian C-spine Rule decision points. Panel C: Spinal cord injury syndromes illustrating complete injury, central cord, anterior cord, Brown-Sequard, and cauda equina patterns. Panel D: Spinal cord injury management priorities including MAP goals, imaging modalities, and spine consultation indications. --- ### VI. Thoracic Trauma Immediately life-threatening thoracic injuries must be identified and treated during the primary survey because they cause death within minutes if not addressed. Tension pneumothorax from one-way valve effect causes progressive pleural air accumulation with mediastinal shift, impaired venous return, and cardiovascular collapse; needle decompression at the second intercostal space midclavicular line or fourth intercostal space anterior axillary line provides immediate temporizing treatment followed by tube thoracostomy. Open pneumothorax from a chest wall defect larger than two-thirds tracheal diameter preferentially draws air through the wound rather than the trachea; three-sided occlusive dressing sealed on three sides allows air egress while preventing entrainment, with subsequent tube thoracostomy remote from the wound. Massive hemothorax exceeding fifteen hundred milliliters initial output or ongoing output exceeding two hundred milliliters per hour typically requires operative thoracotomy for hemorrhage control. Cardiac tamponade from penetrating cardiac injury presents with Beck's triad; pericardiocentesis provides temporizing drainage while arranging emergent thoracotomy. Tube thoracostomy represents the definitive treatment for most significant pneumothorax and hemothorax, draining air and blood while monitoring for ongoing hemorrhage that might require operative intervention. Insertion occurs at the fourth or fifth intercostal space in the anterior to midaxillary line within the triangle of safety bounded by the anterior border of latissimus dorsi, lateral border of pectoralis major, and a horizontal line at the nipple level. Blunt dissection through intercostal muscles followed by finger sweep confirmation of pleural entry prevents lung injury during insertion. Tube size of twenty-eight to thirty-six French adequately drains blood and air in trauma. Connection to a drainage system with underwater seal and suction allows quantification of output guiding decisions about operative intervention. Pulmonary contusion results from direct parenchymal injury causing alveolar hemorrhage and edema that impairs gas exchange, often worsening over the first twenty-four to forty-eight hours before improving. Mechanism typically involves direct impact from blunt force transmitted through the chest wall. Presentation ranges from asymptomatic initial radiographic findings to respiratory failure requiring mechanical ventilation. Chest radiograph shows patchy infiltrates that may not appear immediately, while CT demonstrates contusion extent more accurately. Management is primarily supportive, with supplemental oxygen, careful fluid management avoiding overresuscitation, and mechanical ventilation with lung-protective settings when respiratory failure develops. Pain control enabling deep breathing and cough prevents atelectasis and pneumonia that compound respiratory compromise. Traumatic aortic injury results from high-speed deceleration creating shear forces at the aortic isthmus, the junction between mobile arch and fixed descending aorta, with most patients dying at the scene from free rupture. Survivors reaching the hospital typically have contained rupture with pseudoaneurysm formation, providing a window for diagnosis and treatment. Chest radiograph findings suggesting aortic injury include widened mediastinum exceeding eight centimeters, loss of aortic knob contour, left apical cap, and depression of left mainstem bronchus. CT angiography provides definitive diagnosis with direct visualization of intimal injury, pseudoaneurysm, or surrounding hematoma. Management includes blood pressure and heart rate control with beta-blockade targeting heart rate below eighty and systolic pressure below one hundred, with endovascular stent grafting now preferred over open repair for most injuries. Panel A: Life-threatening thoracic injuries showing tension pneumothorax decompression, open pneumothorax dressing, massive hemothorax drainage, and tamponade management. Panel B: Tube thoracostomy technique demonstrating triangle of safety landmarks, blunt dissection, and finger sweep confirmation. Panel C: Pulmonary contusion radiographic appearance, clinical progression over 24-48 hours, and supportive management approach. Panel D: Traumatic aortic injury mechanism at isthmus, chest radiograph findings, and CT angiography diagnosis with blood pressure management targets. --- ### VII. Abdominal Trauma Abdominal trauma evaluation integrates mechanism, physical examination, imaging, and hemodynamic status to identify injuries requiring operative intervention while avoiding unnecessary surgery for injuries amenable to non-operative management. Blunt abdominal trauma from motor vehicle crashes, falls, and assaults may produce minimal external findings despite significant internal injury, as solid organs absorb energy and hollow viscus injury may not cause immediate peritonitis. Penetrating abdominal trauma from gunshot wounds almost always requires operative exploration due to high incidence of multiple organ injury and unpredictable trajectory, while stab wounds may be managed more selectively based on hemodynamic stability, peritoneal signs, and local wound exploration or imaging findings. Physical examination findings including guarding, rigidity, distension, and seatbelt sign raise concern, but clinical examination sensitivity is limited, particularly in patients with altered mental status or distracting injuries. The Focused Assessment with Sonography in Trauma (FAST) examination provides rapid bedside evaluation for hemoperitoneum and hemopericardium in unstable trauma patients. The examination includes four standard views: right upper quadrant evaluating the hepatorenal recess (Morison's pouch), left upper quadrant evaluating the splenorenal recess, suprapubic view evaluating the pelvis, and subxiphoid view evaluating the pericardium. Free fluid appears as anechoic black stripes in dependent areas between organs. Positive FAST in an unstable patient typically mandates operative exploration without further imaging. Negative FAST does not exclude injury, as solid organ injury without free rupture, hollow viscus injury, and retroperitoneal injuries may not produce detectable free fluid. Extended FAST adds bilateral thoracic views to detect pneumothorax and hemothorax. Solid organ injury management has shifted toward non-operative approaches in hemodynamically stable patients, with observation, serial examinations, and angiographic embolization replacing routine operative exploration. Spleen injuries are graded one through five based on hematoma size, laceration depth, vascular involvement, and degree of devascularization, with higher grades and older age predicting failure of non-operative management. Liver injuries similarly undergo observation in stable patients, with operative intervention reserved for hemodynamic instability or associated injuries requiring surgery. Kidney injuries are managed non-operatively unless shattered kidney, vascular pedicle injury, or urine extravasation necessitates intervention. Angiographic embolization addresses arterial bleeding demonstrated on contrast-enhanced CT, particularly for splenic artery pseudoaneurysms and active hepatic hemorrhage. Hollow viscus injury from blunt or penetrating trauma requires operative repair due to peritoneal contamination causing progressive peritonitis and sepsis. Diagnostic clues include free fluid on CT without identifiable solid organ injury source, particularly when associated with thickened bowel wall, mesenteric stranding, or extraluminal air. The seatbelt sign of abdominal wall ecchymosis from lap belt restraint carries particularly high association with small bowel injury and should maintain high suspicion even when initial imaging appears unremarkable. Delayed diagnosis beyond twenty-four hours significantly increases morbidity and mortality from peritonitis and sepsis. Operative exploration includes thorough inspection of the entire bowel from ligament of Treitz to rectum, with repair or resection depending on injury extent and contamination. Panel A: Abdominal trauma evaluation integrating mechanism, examination findings, hemodynamics, and imaging strategy for blunt and penetrating injuries. Panel B: FAST examination views showing right upper quadrant, left upper quadrant, pelvic, and subxiphoid windows with positive finding appearance. Panel C: Solid organ injury management comparing operative indications with non-operative observation criteria and angiographic embolization role. Panel D: Hollow viscus injury recognition showing CT findings, seatbelt sign association, and importance of timely operative intervention. --- ### VIII. Pelvic and Extremity Trauma Pelvic fractures carry significant mortality risk due to associated hemorrhage from the highly vascular pelvic venous plexus, branches of the internal iliac artery, and fracture surfaces themselves. Fracture patterns are classified by mechanism, with lateral compression causing internal rotation, anteroposterior compression causing external rotation and volume expansion, and vertical shear causing superior displacement. Anteroposterior compression and vertical shear patterns are mechanically unstable and associated with greater blood loss due to disruption of the pelvic ring that normally provides tamponade. Examination findings include pelvic instability to gentle compression, leg length discrepancy, rotational deformity, and scrotal or labial hematoma. Single examination for instability is acceptable, but repeated manipulation worsens bleeding and should be avoided once instability is identified. Pelvic fracture management integrates hemorrhage control, mechanical stabilization, and damage control resuscitation for associated shock. Pelvic binding with commercial binder or sheet wrapped tightly around the greater trochanters reduces pelvic volume, provides mechanical stabilization, and facilitates tamponade of venous bleeding. Application should occur as early as possible, including prehospital, with maintenance until definitive stabilization. Massive transfusion protocol activation addresses hemorrhagic shock while hemorrhage control proceeds. Arterial bleeding demonstrated on CT angiography as contrast extravasation requires angiographic embolization of bleeding vessels. Preperitoneal pelvic packing provides an alternative or adjunct to embolization, directly compressing bleeding in the pelvis through a suprapubic approach. External fixation provides temporary mechanical stabilization when internal fixation is not immediately feasible. Open fractures represent orthopedic emergencies due to fracture site contamination creating infection risk that increases with time to treatment. Classification by the Gustilo-Anderson system guides treatment intensity: Grade I with wound less than one centimeter and minimal contamination, Grade II with wound one to ten centimeters without extensive soft tissue damage, and Grade III with wounds exceeding ten centimeters, extensive soft tissue damage, or high-energy mechanisms subdivided by adequacy of soft tissue coverage and vascular injury. Treatment includes intravenous antibiotics initiated immediately, typically cefazolin with added gram-negative coverage for Grade III injuries, wound irrigation, tetanus prophylaxis, and operative debridement within six to eight hours for Grade III injuries. Fracture stabilization may be temporary with external fixation initially, with definitive internal fixation after soft tissue recovery. Vascular injury complicating extremity trauma threatens limb viability with ischemia time exceeding six hours significantly increasing amputation risk. Hard signs of vascular injury mandating immediate operative exploration include pulsatile bleeding, expanding hematoma, absent distal pulses, bruit or thrill, and signs of limb ischemia including pain, pallor, pulselessness, paresthesias, and paralysis. Soft signs including decreased pulse compared to contralateral extremity, proximity of wound to major vessel, associated nerve injury, and non-expanding hematoma warrant further evaluation with ankle-brachial index measurement and CT angiography. Management depends on findings, with operative repair, endovascular intervention, or observation appropriate for different injury patterns. Panel A: Pelvic fracture patterns showing lateral compression, anteroposterior compression, and vertical shear mechanisms with associated bleeding risk. Panel B: Pelvic fracture management with binder application technique, massive transfusion activation, and hemorrhage control options. Panel C: Open fracture classification by Gustilo-Anderson grades with wound characteristics and treatment implications including antibiotic selection. Panel D: Vascular injury evaluation showing hard signs mandating surgery and soft signs prompting further workup with ankle-brachial index and CT angiography. --- ### IX. Burns Burn injury assessment determines depth, extent, and need for specialized care, with accurate initial evaluation guiding fluid resuscitation and disposition decisions. Superficial burns involve only epidermis, appearing red and painful without blisters, healing within one week without scarring. Partial thickness burns extend into dermis, producing blisters and intense pain from exposed nerve endings, with superficial partial thickness healing within two to three weeks while deep partial thickness may require grafting. Full thickness burns destroy entire dermis and may extend into subcutaneous tissue, appearing white, waxy, or charred with absent sensation due to nerve destruction, always requiring grafting for wound closure. Total body surface area estimation uses the Rule of Nines dividing the body into regions of nine percent (head, each arm, anterior and posterior portions of each leg segment) or eighteen percent (anterior trunk, posterior trunk, each entire leg), with the patient's palm representing approximately one percent for smaller or irregular burns. Fluid resuscitation prevents burn shock from massive third-spacing that occurs over the first twenty-four to forty-eight hours in significant burns. The Parkland formula calculates twenty-four-hour fluid requirement as four milliliters times body weight in kilograms times percent total body surface area burned, using lactated Ringer's solution. Half the calculated volume is administered in the first eight hours from time of burn (not time of arrival), with the remaining half over the subsequent sixteen hours. Urine output of zero point five milliliters per kilogram per hour in adults guides adjustment, with increased rate if output is inadequate and decreased rate if exceeding one milliliter per kilogram per hour to avoid complications from over-resuscitation including abdominal compartment syndrome, pulmonary edema, and extremity compartment syndrome. Burns less than twenty percent total body surface area in adults typically do not require formula-guided resuscitation. Inhalation injury significantly increases mortality and should be suspected in any patient with facial burns, singed nasal hairs, carbonaceous sputum, hoarseness, or history of closed-space fire exposure. Upper airway thermal injury from superheated air causes progressive edema that can rapidly progress to complete obstruction; early intubation before swelling maximizes safety. Lower airway chemical injury from smoke inhalation damages bronchial mucosa, causing bronchospasm, impaired mucociliary clearance, and risk of acute respiratory distress syndrome. Carbon monoxide poisoning from incomplete combustion causes tissue hypoxia despite normal pulse oximetry readings, which measure oxyhemoglobin without distinguishing carboxyhemoglobin; treatment is one hundred percent oxygen by non-rebreather mask or hyperbaric oxygen for severe poisoning. Cyanide poisoning from combustion of synthetic materials in house fires may compound carbon monoxide effects, treated with hydroxocobalamin. Burn center transfer criteria identify patients benefiting from specialized care unavailable at community hospitals. These include partial thickness burns exceeding ten percent total body surface area, burns involving face, hands, feet, genitalia, perineum, or major joints, full thickness burns of any size, electrical and chemical burns, burns with inhalation injury, burns in patients with significant comorbidities, burns with associated trauma when burn injury poses greater risk, and circumferential burns that may require escharotomy. Circumferential full thickness burns of extremities or chest cause compartment syndrome and respiratory compromise respectively as non-elastic eschar prevents expansion during edema development, requiring escharotomy incisions through burn tissue to release constriction. Panel A: Burn depth classification showing superficial, partial thickness, and full thickness characteristics with healing expectations and treatment implications. Panel B: Total body surface area estimation using Rule of Nines diagram and palm estimation method for irregular burns. Panel C: Parkland formula fluid resuscitation calculation with timing distribution and urine output monitoring for adjustment. Panel D: Inhalation injury recognition signs, early intubation indication, and carbon monoxide plus cyanide treatment approaches. --- ### X. Special Trauma Populations Pediatric trauma differs from adult trauma due to developmental anatomic and physiologic characteristics that alter injury patterns, clinical presentation, and management approaches. The proportionally larger head predisposes children to traumatic brain injury from any mechanism, while the compliant chest wall transmits energy to internal structures without rib fractures that would indicate severity in adults. The relatively larger solid organs with less protective musculature and fat increase susceptibility to hepatic and splenic injury. Fluid resuscitation uses weight-based dosing at twenty milliliters per kilogram boluses. Vital sign interpretation requires age-specific reference ranges, as children maintain blood pressure through tachycardia and vasoconstriction until late decompensation produces precipitous hypotension. Non-accidental trauma must be considered when injury patterns are inconsistent with reported mechanism, particularly in non-ambulatory children with long bone fractures. Geriatric trauma presents unique challenges from altered physiology, comorbidities, and medication effects that modify injury patterns and clinical presentation. Falls represent the most common mechanism in elderly patients, often from standing height rather than significant force. Chronic anticoagulation increases bleeding risk and severity, with subdural hematoma occurring more readily due to brain atrophy creating tension on bridging veins. Beta-blocker use blunts tachycardic response to hemorrhage, causing patients to appear hemodynamically stable despite significant blood loss. Cervical spine injury occurs at lower-energy mechanisms due to degenerative changes, warranting lower imaging thresholds. Mortality rates for similar injury severity scores are higher in elderly patients, justifying more aggressive evaluation and treatment and lower thresholds for trauma center transfer. Pregnant trauma patients require simultaneous consideration of maternal and fetal wellbeing, with maternal resuscitation constituting the most effective fetal resuscitation. After twenty weeks gestation, left lateral positioning or manual uterine displacement prevents inferior vena cava compression from the gravid uterus that can reduce venous return by thirty percent. Fetal monitoring beginning at twenty-four weeks viability provides assessment of fetal wellbeing, with non-reassuring patterns potentially indicating placental abruption or fetal distress. Placental abruption from even minor trauma represents the leading cause of fetal death in pregnant trauma, presenting with abdominal pain, vaginal bleeding, uterine tenderness, and non-reassuring fetal heart tones. Rh-negative mothers require RhoGAM administration to prevent isoimmunization from fetal-maternal hemorrhage. Perimortem cesarean section should be performed within four to five minutes of maternal cardiac arrest at or beyond twenty-four weeks gestation. Penetrating trauma management varies by anatomic region and hemodynamic status, with certain injuries mandating immediate operative exploration while others permit selective non-operative management. Penetrating neck trauma is divided into zones: Zone I from clavicles to cricoid containing major vessels and thoracic inlet structures, Zone II from cricoid to angle of mandible with surgically accessible vasculature, and Zone III above the mandible angle with difficult surgical access. Gunshot wounds to the abdomen typically require operative exploration due to unpredictable trajectory and high incidence of multiple organ injury. Stab wounds to the abdomen may be managed selectively with serial examinations, local wound exploration, or CT imaging in hemodynamically stable patients without peritonitis. All hemodynamically unstable patients with penetrating trauma require immediate operative intervention. Panel A: Pediatric trauma differences showing proportionally larger head, compliant chest, and age-specific vital signs with weight-based resuscitation. Panel B: Geriatric trauma considerations including fall mechanisms, anticoagulation effects, blunted vital sign response, and increased cervical spine risk. Panel C: Pregnant trauma management with left lateral positioning, fetal monitoring, abruption recognition, and RhoGAM indication. Panel D: Penetrating trauma by region showing neck zones, abdominal gunshot versus stab approach, and operative indications. --- ## Summary - Primary survey follows ABCDE sequence with immediate treatment of life-threatening findings: airway with cervical spine protection, breathing threats including tension pneumothorax and massive hemothorax, circulation with hemorrhage control and resuscitation, disability assessment, and exposure with hypothermia prevention - Tension pneumothorax is a clinical diagnosis requiring immediate needle decompression at second intercostal space midclavicular line or fourth-fifth intercostal space anterior axillary line followed by tube thoracostomy - Damage control resuscitation uses permissive hypotension targeting systolic 80-90 mmHg, balanced 1:1:1 transfusion of packed cells, plasma, and platelets, and TXA administration within three hours - Traumatic brain injury management focuses on preventing secondary injury through avoidance of hypoxia and hypotension, with osmotic therapy for herniation signs - Cervical spine clearance uses NEXUS or Canadian C-spine criteria for low-risk patients, with CT imaging for those not meeting clearance criteria - FAST examination evaluates four views for free fluid: right upper quadrant, left upper quadrant, pelvic, and subxiphoid cardiac views - Pelvic fractures require early binder application with massive transfusion protocol activation for hemorrhagic shock and angiographic embolization for arterial bleeding - Burns require Parkland formula resuscitation of 4 mL/kg times percent TBSA with half administered in the first eight hours from burn time - Pregnant trauma patients require left lateral positioning after twenty weeks and RhoGAM for Rh-negative mothers, with maternal resuscitation prioritized as the best fetal resuscitation --- ## Key Terms | Term | Definition | |------|------------| | ATLS | Advanced Trauma Life Support standardized approach to trauma resuscitation | | FAST | Focused Assessment with Sonography in Trauma evaluating for free fluid | | MTP | Massive Transfusion Protocol providing balanced blood product delivery | | TXA | Tranexamic acid antifibrinolytic reducing mortality in bleeding trauma | | GCS | Glasgow Coma Scale scoring neurologic function by eye, verbal, and motor responses | | TBSA | Total Body Surface Area for burn extent estimation | | Damage control resuscitation | Approach limiting crystalloid while providing balanced blood products with permissive hypotension | | Permissive hypotension | Accepting lower blood pressure targets to reduce ongoing hemorrhage while maintaining minimal perfusion | --- *This content is subject to the [MIT License](https://opensource.org/licenses/MIT). © 2024–2026 Hibbert School of Medicine.*