# Seminar 14: Trauma Surgery ## General Surgery Clerkship - Unit 14 --- ## Learning Objectives By the end of this seminar, students will be able to: 1. Apply the systematic ATLS approach to initial trauma evaluation including primary and secondary surveys 2. Classify hemorrhagic shock by severity and implement appropriate resuscitation strategies including damage control principles 3. Recognize life-threatening thoracic injuries and perform emergent interventions including needle decompression and tube thoracostomy 4. Evaluate abdominal trauma using FAST examination and CT imaging to determine operative versus nonoperative management 5. Apply damage control surgery principles including indications, techniques, and staged operative approach 6. Recognize special considerations in pediatric, geriatric, and pregnant trauma patients --- ## Seminar Outline ### I. Initial Trauma Assessment and Primary Survey The Advanced Trauma Life Support protocol provides a systematic framework for evaluating and managing injured patients, emphasizing rapid identification and treatment of life-threatening conditions before comprehensive evaluation. The primary survey follows the ABCDE sequence, addressing airway, breathing, circulation, disability, and exposure in order of physiological priority. This structured approach ensures that the most immediately life-threatening conditions are identified and addressed first, preventing death from airway obstruction, inadequate ventilation, or uncontrolled hemorrhage during the initial resuscitation phase. The primary survey should be completed within minutes of patient arrival with simultaneous resuscitation interventions. Airway assessment begins with verbal contact, as a patient who can speak clearly has a patent airway sufficient for the moment. Signs of airway compromise include stridor, gurgling, hoarseness, and inability to speak. Foreign bodies, blood, vomitus, and secretions should be cleared by suction and manual extraction. The jaw thrust maneuver maintains cervical spine immobilization while opening the airway in patients with suspected cervical injury. Definitive airway management with endotracheal intubation is indicated for Glasgow Coma Scale of eight or less, inability to protect the airway, anticipated clinical course requiring airway protection, or severe facial trauma precluding noninvasive management. Surgical airway through cricothyroidotomy is required when endotracheal intubation cannot be achieved. Breathing assessment evaluates ventilatory adequacy through inspection of chest wall movement, auscultation of breath sounds, and monitoring of oxygen saturation. Life-threatening chest injuries requiring immediate intervention during the primary survey include tension pneumothorax, open pneumothorax, and massive hemothorax. Tension pneumothorax presents with hypotension, distended neck veins, absent breath sounds, and tracheal deviation and requires immediate needle decompression followed by tube thoracostomy. Open pneumothorax, or sucking chest wound, requires occlusive dressing with one side unsealed followed by tube thoracostomy. Massive hemothorax with greater than 1500 milliliters of blood loss requires chest tube placement and consideration of thoracotomy. Circulation assessment focuses on hemorrhage recognition and control. External hemorrhage should be controlled with direct pressure, and sources of occult hemorrhage in the chest, abdomen, pelvis, and extremities should be identified. Hypotension with tachycardia, delayed capillary refill, and altered mental status indicate shock requiring aggressive intervention. Two large-bore peripheral intravenous catheters should be placed with initiation of crystalloid resuscitation and blood product administration based on clinical status. The Focused Assessment with Sonography for Trauma examination evaluates for free intraperitoneal fluid suggesting hemoperitoneum in the unstable patient, guiding decision-making regarding operative intervention versus further resuscitation. Panel A: ATLS primary survey algorithm showing ABCDE sequence with interventions at each step and decision points for advanced airway management. Panel B: Airway assessment and management techniques including jaw thrust, oropharyngeal airway, and cricothyroidotomy landmarks. Panel C: Life-threatening chest injuries requiring immediate intervention during primary survey with clinical findings and management. Panel D: FAST examination technique showing four views including right upper quadrant, left upper quadrant, subxiphoid, and pelvis with positive and negative examples. --- ### II. Secondary Survey and Adjuncts The secondary survey represents a comprehensive head-to-toe physical examination performed only after the primary survey is complete and resuscitation has been initiated. This systematic evaluation identifies all injuries, establishes injury patterns, and guides further diagnostic imaging and definitive management. The AMPLE history gathers essential information including allergies, medications particularly anticoagulants and beta-blockers, past medical history and previous surgeries, last oral intake, and events surrounding the injury mechanism. The mechanism of injury provides important information regarding expected injury patterns and energy transfer, guiding focused evaluation of anatomic regions at highest risk. The head and face examination includes assessment for scalp lacerations, skull fractures, periorbital ecchymosis suggesting basilar skull fracture, Battle sign over the mastoid indicating temporal bone fracture, hemotympanum, and facial bone stability. Pupillary examination documents size, reactivity, and symmetry with attention to fixed dilated pupil suggesting uncal herniation requiring immediate intervention. Cervical spine evaluation includes palpation for midline tenderness and step-off deformity while maintaining immobilization until clinical or radiographic clearance. The chest examination assesses for rib fractures, subcutaneous emphysema, and cardiac contusion, while the abdominal examination evaluates for distension, peritoneal signs, and evidence of seat belt or handlebar injuries suggesting hollow viscus injury. Extremity examination systematically evaluates all four limbs for deformity, swelling, ecchymosis, and neurovascular status. Pelvic stability is assessed with gentle anteroposterior and lateral compression, with unstable pelvic fractures requiring pelvic binder application and evaluation for associated hemorrhage. The back examination requires log-rolling the patient with spinal precautions to evaluate for wounds, deformity, and tenderness. Rectal examination assesses for blood indicating gastrointestinal injury, prostatic position suggesting urethral injury, and sphincter tone indicating spinal cord function. Genitourinary examination in males evaluates for blood at the urethral meatus contraindicating Foley catheter placement until retrograde urethrography excludes urethral injury. Adjuncts to the secondary survey include imaging studies tailored to the clinical situation and injury mechanism. Chest radiography identifies pneumothorax, hemothorax, widened mediastinum suggesting aortic injury, and rib fractures. Pelvic radiography identifies fractures that may explain hemodynamic instability or indicate need for external fixation or angioembolization. Focused Assessment with Sonography for Trauma may be repeated during the secondary survey if clinical status changes. Computed tomography with intravenous contrast represents the gold standard for comprehensive evaluation of stable patients, providing detailed assessment of head, cervical spine, chest, abdomen, and pelvis. CT angiography evaluates for vascular injuries when indicated by mechanism or examination findings. Panel A: Secondary survey systematic examination sequence from head to pelvis with key findings at each anatomic region. Panel B: Signs of basilar skull fracture including raccoon eyes, Battle sign, hemotympanum, and CSF rhinorrhea or otorrhea. Panel C: Pelvic fracture patterns showing lateral compression, anteroposterior compression, and vertical shear with stability implications. Panel D: CT imaging examples demonstrating splenic laceration, hepatic contusion, and retroperitoneal hematoma from blunt abdominal trauma. --- ### III. Hemorrhagic Shock Classification and Resuscitation Hemorrhagic shock results from inadequate tissue perfusion due to blood loss and represents the leading cause of preventable death following trauma. The American College of Surgeons classification divides hemorrhagic shock into four classes based on estimated blood loss and physiological response, guiding resuscitation intensity. Class I shock with blood loss less than fifteen percent of blood volume produces minimal physiological derangement with normal blood pressure and heart rate. Class II shock with fifteen to thirty percent blood loss causes tachycardia and narrowed pulse pressure but preserved blood pressure. Recognition of early shock classes enables intervention before progression to decompensated states with irreversible organ damage. Class III hemorrhagic shock represents loss of thirty to forty percent of blood volume and manifests with tachycardia exceeding 120 beats per minute, hypotension, decreased pulse pressure, and altered mental status with confusion and anxiety. Urine output decreases as renal perfusion becomes inadequate. Class IV shock with blood loss exceeding forty percent produces severe hypotension, tachycardia greater than 140, marked mental status depression, and negligible urine output. Patients in Class III and IV shock require immediate blood transfusion in addition to crystalloid resuscitation and will not stabilize with crystalloid alone. The transition from compensated to decompensated shock represents a critical juncture where timely intervention determines survival. Contemporary trauma resuscitation has evolved toward damage control resuscitation principles that prioritize early blood product administration and permissive hypotension over aggressive crystalloid administration. Massive transfusion protocols deliver red blood cells, plasma, and platelets in balanced ratios approaching one to one to one, replacing whole blood rather than component-deficient crystalloid. Tranexamic acid administered within three hours of injury reduces mortality in bleeding trauma patients by inhibiting fibrinolysis. Permissive hypotension with target systolic pressure of 80 to 90 millimeters of mercury limits ongoing hemorrhage from uncontrolled surgical sources while maintaining adequate perfusion, though this approach is contraindicated in traumatic brain injury where cerebral perfusion pressure must be maintained. Crystalloid resuscitation remains part of initial trauma management but has been de-emphasized based on recognition of crystalloid-associated complications. Lactated Ringer solution is preferred over normal saline due to lower chloride content and reduced risk of hyperchloremic acidosis. Initial bolus of one to two liters with assessment of response guides further fluid versus blood product administration. Failure to respond to crystalloid or transient response with recurrent hypotension indicates ongoing hemorrhage requiring blood products and source control. The goal of resuscitation shifts from volume replacement to hemorrhage control and reversal of the lethal triad of acidosis, hypothermia, and coagulopathy that perpetuates bleeding and predicts death in severe hemorrhagic shock. Panel A: Classification of hemorrhagic shock showing Classes I through IV with blood loss percentages and physiological parameters at each class. Panel B: Damage control resuscitation algorithm illustrating massive transfusion protocol activation, blood product ratios, and adjuncts including tranexamic acid. Panel C: Lethal triad diagram showing interrelationship between acidosis, hypothermia, and coagulopathy with physiological mechanisms. Panel D: Resuscitation endpoints including lactate clearance, base deficit correction, and reversal of coagulopathy as guides to adequacy of resuscitation. --- ### IV. Thoracic Trauma Thoracic trauma accounts for approximately twenty-five percent of trauma deaths, with most life-threatening injuries manageable through airway control and tube thoracostomy without need for operative intervention. The immediately life-threatening injuries identified during the primary survey include tension pneumothorax, open pneumothorax, massive hemothorax, cardiac tamponade, and flail chest with pulmonary contusion. Tension pneumothorax develops when air accumulates under pressure in the pleural space, collapsing the ipsilateral lung and shifting the mediastinum with compression of the contralateral lung and impaired venous return. This clinical diagnosis requires immediate needle decompression in the second intercostal space followed by tube thoracostomy. Hemothorax results from bleeding into the pleural space from intercostal vessels, internal mammary artery, or pulmonary parenchymal injury. Massive hemothorax defined as greater than 1500 milliliters of blood or ongoing output exceeding 200 milliliters per hour for two to four hours indicates need for operative thoracotomy for hemorrhage control. Chest tube placement in the fifth intercostal space at the anterior axillary line provides both diagnostic information through initial output and therapeutic drainage. Autotransfusion of shed blood collected from the chest tube may be performed to reduce allogeneic blood requirements in patients with significant hemothorax and limited contamination. Cardiac tamponade results from blood accumulation in the pericardial sac compressing the heart and impairing filling. The classic Beck triad of hypotension, distended neck veins, and muffled heart sounds is present in only a minority of patients. Pulsus paradoxus with greater than ten millimeter mercury decrease in systolic pressure during inspiration provides additional diagnostic clue. FAST examination demonstrating pericardial fluid in a hypotensive patient supports the diagnosis. Emergency pericardiocentesis through the subxiphoid approach provides temporizing decompression, though definitive treatment requires operative pericardial window or sternotomy for repair of the underlying cardiac or great vessel injury. Potentially life-threatening injuries identified during the secondary survey include pulmonary contusion, blunt cardiac injury, traumatic aortic disruption, diaphragmatic rupture, and tracheobronchial injury. Pulmonary contusion manifests as progressive hypoxemia over hours following injury, with bilateral alveolar infiltrates on chest radiograph. Traumatic aortic disruption typically occurs at the aortic isthmus just distal to the left subclavian artery and presents with widened mediastinum on chest radiograph, confirmed by CT angiography. The majority of patients with aortic injury who reach the hospital have contained rupture amenable to endovascular repair with covered stent grafts, which has largely replaced open surgical repair. Panel A: Tension pneumothorax pathophysiology showing progressive air accumulation, mediastinal shift, and impaired venous return with clinical findings. Panel B: Chest tube insertion technique demonstrating fifth intercostal space landmark, blunt dissection, and tube positioning for hemothorax drainage. Panel C: Cardiac tamponade illustration with pericardial blood accumulation, compressed cardiac chambers, and subxiphoid pericardiocentesis approach. Panel D: CT angiography demonstrating traumatic aortic injury at the isthmus with contained rupture and intimal flap. --- ### V. Abdominal Trauma Evaluation and Management Abdominal trauma evaluation differs fundamentally between blunt and penetrating mechanisms, with management algorithms tailored to the injury pattern and hemodynamic status. Blunt abdominal trauma most commonly injures solid organs with the spleen and liver representing the most frequently injured structures, while hollow viscus injury occurs in approximately five percent of blunt abdominal trauma. Penetrating abdominal trauma produces higher rates of hollow viscus injury requiring operative repair, with gunshot wounds having significantly higher injury rates than stab wounds due to greater energy transfer and unpredictable projectile trajectory. The Focused Assessment with Sonography for Trauma provides rapid bedside evaluation for free intraperitoneal fluid in hemodynamically unstable patients. Positive FAST in an unstable patient with appropriate mechanism indicates need for emergent laparotomy for hemorrhage control. Negative FAST does not exclude significant injury, particularly retroperitoneal injuries and hollow viscus injuries that do not produce free fluid. In the stable patient, FAST has been largely supplanted by CT scanning, which provides detailed evaluation of solid organ injury grade, active extravasation, and hollow viscus injury. CT imaging guides nonoperative management decisions and identifies injuries requiring operative intervention. Nonoperative management has become the standard of care for blunt solid organ injuries in hemodynamically stable patients regardless of injury grade. This approach developed from recognition that many solid organ injuries will heal without operative intervention if bleeding has ceased, with surgery reserved for hemodynamic instability or failure of nonoperative management. Splenic injury management includes observation with serial examinations for low-grade injuries, angioembolization for higher-grade injuries with active extravasation in stable patients, and splenectomy for hemodynamic instability. Hepatic injury management follows similar principles, with the majority managed nonoperatively and operative intervention reserved for instability, typically employing packing techniques. Indications for laparotomy in abdominal trauma include hemodynamic instability with positive FAST or appropriate mechanism, peritonitis on examination indicating hollow viscus injury, evisceration, impaled objects, free air on imaging indicating hollow viscus perforation, and specific CT findings suggesting injuries requiring repair. Gunshot wounds traversing the peritoneal cavity generally require laparotomy given high injury rates, while selective nonoperative management may be appropriate for tangential wounds. Anterior abdominal stab wounds may be evaluated with local wound exploration to assess fascial penetration, with serial examinations or diagnostic laparoscopy for equivocal cases. The decision for operative versus nonoperative management requires integration of mechanism, hemodynamic status, examination findings, and imaging results. Panel A: Comparison of blunt versus penetrating abdominal trauma showing different injury patterns, organ injury frequencies, and management considerations. Panel B: Management algorithm for blunt abdominal trauma stratified by hemodynamic status with FAST and CT decision points. Panel C: Splenic injury grading from Grade I subcapsular hematoma through Grade V shattered spleen with corresponding management approaches. Panel D: Indications for emergent laparotomy including hemodynamic instability, peritonitis, evisceration, and imaging findings requiring operative intervention. --- ### VI. Pelvic Trauma and Genitourinary Injury Pelvic fractures result from high-energy mechanisms and carry significant mortality due to associated hemorrhage from the presacral venous plexus and branches of the internal iliac arterial system. Fracture classification according to the Young-Burgess system identifies lateral compression injuries from lateral force, anteroposterior compression injuries from frontal force, and vertical shear injuries from axial loading, each with characteristic fracture patterns and stability implications. Anteroposterior compression type III injuries, known as open book fractures, and vertical shear injuries are mechanically unstable with high rates of hemorrhage requiring aggressive intervention. The pelvic binder or sheet wrap provides external compression to reduce pelvic volume and tamponade venous hemorrhage as a temporizing measure. Hemorrhage control in pelvic fractures employs a multimodal approach including external compression, preperitoneal packing, and angioembolization. The decision tree begins with pelvic binder application for suspected unstable fractures followed by FAST examination to evaluate for intraperitoneal hemorrhage. Positive FAST in an unstable patient with pelvic fracture requires laparotomy for abdominal hemorrhage control, with preperitoneal packing performed simultaneously or sequentially if pelvic hemorrhage continues. Angioembolization addresses arterial bleeding identified on CT angiography in patients who respond to initial resuscitation or have ongoing transfusion requirements. Resuscitative endovascular balloon occlusion of the aorta provides temporary hemorrhage control in extremis by occluding aortic flow to the pelvis. Genitourinary injuries frequently accompany pelvic fractures and require systematic evaluation to prevent complications. Blood at the urethral meatus, scrotal hematoma, or high-riding prostate on rectal examination suggests urethral injury and contraindicates Foley catheter placement until retrograde urethrography excludes urethral disruption. Bladder injury may be intraperitoneal or extraperitoneal, with intraperitoneal rupture typically requiring operative repair while extraperitoneal rupture is usually managed with catheter drainage alone. Renal injury evaluation with CT imaging guides management from observation for low-grade injuries through angioembolization for active extravasation to nephrectomy for shattered kidney or renal pedicle injury in unstable patients. Ureteral injury occurs rarely in blunt trauma but may complicate penetrating injury and has a high rate of delayed diagnosis. Hematuria may be absent even with significant ureteral injury. CT with delayed phase imaging demonstrating contrast extravasation or lack of ureteral opacification suggests injury requiring operative repair with primary anastomosis or reimplantation depending on location. External genital injuries including penile fracture and testicular rupture require prompt operative exploration and repair. The complexity of pelvic and genitourinary trauma underscores the importance of multidisciplinary management involving trauma surgery, orthopedic surgery, urology, and interventional radiology. Panel A: Young-Burgess pelvic fracture classification showing lateral compression, anteroposterior compression, and vertical shear patterns with fracture lines and stability characteristics. Panel B: Pelvic hemorrhage management algorithm from binder application through angioembolization and preperitoneal packing with decision points. Panel C: Genitourinary evaluation pathway showing indications for retrograde urethrography, cystography, and CT imaging based on clinical findings. Panel D: Bladder injury comparison between intraperitoneal rupture requiring surgery and extraperitoneal rupture managed with catheter drainage. --- ### VII. Damage Control Surgery Damage control surgery represents a fundamental shift from traditional operative philosophy, prioritizing patient physiology over anatomical restoration when the lethal triad of acidosis, hypothermia, and coagulopathy threatens survival. The concept emerged from recognition that severely injured patients die not from failure to complete operative repair but from progressive physiological derangement during prolonged operations. Abbreviated initial surgery focuses on hemorrhage control and contamination containment with temporary closure, followed by resuscitation to restore normal physiology, and subsequent return to the operating room for definitive repair once the patient has been optimized. Indications for damage control surgery include physiological parameters reflecting decompensated shock. Core temperature below 34 degrees Celsius indicates severe hypothermia impairing coagulation factor function. Arterial pH below 7.2 reflects profound acidosis from tissue hypoperfusion and anaerobic metabolism. Clinical coagulopathy manifest as diffuse microvascular bleeding or laboratory evidence of coagulopathy with INR greater than 1.5 or platelet count below 50,000 indicates consumption and dilution of clotting factors. Massive transfusion exceeding ten units of packed red blood cells predicts damage control candidacy. The decision to implement damage control must be made early rather than after prolonged futile attempts at definitive repair. Damage control techniques vary by injury but share the common principle of rapid control rather than definitive repair. Hepatic injuries are managed with perihepatic packing using laparotomy pads placed strategically to tamponade bleeding surfaces, with packing left in place for 24 to 48 hours before removal at planned reoperation. Splenic injury typically requires splenectomy in the damage control setting as splenic salvage procedures are time-consuming. Intestinal injuries are managed with resection using staplers without anastomosis, leaving stapled ends in discontinuity for later restoration of continuity. Major vascular injuries may be managed with temporary intraluminal shunts maintaining distal perfusion until definitive repair. The abdomen is left open with temporary closure using negative pressure wound therapy to prevent abdominal compartment syndrome. The staged approach following initial damage control surgery involves resuscitation in the intensive care unit to correct hypothermia with active warming, reverse acidosis through restoration of perfusion, and correct coagulopathy with blood product transfusion guided by thromboelastography or rotational thromboelastometry. Definitive repair is typically performed 24 to 48 hours following initial surgery once normal temperature, pH, and coagulation have been restored. This second operation addresses intestinal restoration, removal of packing, definitive vascular repair, and abdominal wall closure when feasible. Multiple planned returns to the operating room may be necessary for complex injuries or delayed closure of the open abdomen. Panel A: Lethal triad showing physiological thresholds for acidosis, hypothermia, and coagulopathy that indicate damage control surgery with mechanisms of each component. Panel B: Damage control laparotomy techniques including perihepatic packing, stapled bowel discontinuity, and temporary vascular shunt placement. Panel C: Staged approach timeline showing initial abbreviated surgery, ICU resuscitation phase with targets, and return for definitive repair. Panel D: Temporary abdominal closure with negative pressure wound therapy demonstrating technique and prevention of abdominal compartment syndrome. --- ### VIII. Traumatic Brain Injury Traumatic brain injury represents a leading cause of death and disability following trauma, with outcomes determined by both primary injury from the initial mechanical insult and secondary injury from subsequent ischemia, hypoxia, and edema. Severity classification based on Glasgow Coma Scale defines mild TBI with GCS 13 to 15, moderate TBI with GCS 9 to 12, and severe TBI with GCS 8 or less. Patients with severe TBI require endotracheal intubation for airway protection and should be managed in specialized trauma centers with neurosurgical capability. The primary goals of management focus on preventing secondary brain injury through maintenance of adequate cerebral perfusion and oxygenation. Types of intracranial hemorrhage have distinct pathophysiology, imaging characteristics, and management implications. Epidural hematoma results from arterial bleeding, typically from the middle meningeal artery following temporal bone fracture, and presents with the classic lucid interval followed by rapid deterioration. CT demonstrates a lens-shaped hyperdense collection that does not cross suture lines. Subdural hematoma results from tearing of bridging veins and appears as a crescent-shaped collection conforming to the brain surface. Subarachnoid hemorrhage presents as blood within the sulci and may result from vessel injury or extension of parenchymal contusion. Intraparenchymal hemorrhage and contusion represent direct brain tissue injury with associated edema. Management of severe TBI centers on optimization of cerebral perfusion pressure, calculated as mean arterial pressure minus intracranial pressure, with target greater than 60 to 70 millimeters of mercury. Intracranial pressure monitoring through intraventricular catheter or intraparenchymal monitor guides therapy, with intervention indicated for ICP exceeding 20 millimeters of mercury. Tiered therapy for elevated ICP progresses from head elevation and sedation through osmotic therapy with mannitol or hypertonic saline, to paralysis, barbiturate coma, and decompressive craniectomy in refractory cases. Hyperventilation is avoided except as temporizing measure for herniation given cerebral vasoconstriction and reduced perfusion. Surgical intervention for traumatic brain injury includes craniotomy for evacuation of epidural and subdural hematomas meeting size and clinical criteria. Epidural hematoma greater than 30 cubic centimeters, subdural hematoma greater than 10 millimeters thickness or causing greater than 5 millimeter midline shift, and significant neurological deficit or deterioration indicate operative intervention. Decompressive craniectomy removes a large bone flap to allow brain swelling without herniation and may improve outcomes in selected patients with refractory intracranial hypertension. Cervical spine injury must be presumed in all TBI patients until cleared clinically or radiographically, with CT imaging of the cervical spine indicated for all patients with altered mental status or distracting injuries. Panel A: Glasgow Coma Scale components including eye opening, verbal response, and motor response with scoring criteria and severity classification. Panel B: CT imaging characteristics of epidural hematoma showing lens shape limited by sutures versus subdural hematoma showing crescent shape conforming to brain. Panel C: Cerebral perfusion pressure management algorithm showing ICP monitoring, tiered interventions, and targets for MAP and CPP. Panel D: Indications for craniotomy based on hematoma size, midline shift, and clinical deterioration with decision pathway. --- ### IX. Extremity Trauma Vascular injury to the extremities presents with hard signs indicating certain vascular injury or soft signs suggesting possible injury requiring further evaluation. Hard signs include pulseless extremity, active hemorrhage, expanding hematoma, bruit or thrill over the injury, and signs of distal ischemia. Any hard sign mandates immediate operative exploration or angiographic intervention without delay for additional imaging. Soft signs including diminished but palpable pulses, injury proximity to major vessels, stable hematoma, history of significant hemorrhage, and neurological deficit associated with vascular structures warrant further evaluation with CT angiography or formal angiography to define the injury and guide management. Compartment syndrome represents a surgical emergency where elevated pressure within a fascial compartment compromises perfusion to muscles and nerves, leading to irreversible necrosis if untreated. The condition most commonly occurs in the leg following tibial fracture but may affect any compartment including the forearm, thigh, hand, foot, and buttock. The classic presentation includes pain out of proportion to injury, pain with passive stretch of muscles within the affected compartment, and paresthesias in the distribution of nerves traversing the compartment. Pulselessness and paralysis represent late findings indicating established ischemia. Compartment pressure measurement exceeding 30 millimeters of mercury or within 30 of diastolic pressure confirms the diagnosis. Treatment of compartment syndrome requires emergent fasciotomy to decompress all compartments within the affected extremity. Four-compartment fasciotomy of the leg releases the anterior, lateral, superficial posterior, and deep posterior compartments through two incisions. The volar forearm requires release of the superficial and deep volar compartments along with the mobile wad. Fasciotomy incisions are left open with negative pressure wound therapy until swelling resolves, typically requiring delayed primary closure or skin grafting. The consequences of missed compartment syndrome include muscle necrosis requiring debridement or amputation, contracture, and neurological deficit, emphasizing the importance of maintaining high clinical suspicion in at-risk patients. Mangled extremity assessment guides the decision between limb salvage and primary amputation in severe extremity trauma. The Mangled Extremity Severity Score incorporates skeletal and soft tissue injury, limb ischemia, shock, and patient age to predict likelihood of successful limb salvage. While no scoring system provides definitive guidance, factors favoring primary amputation include warm ischemia time exceeding six hours, severe crush injury with extensive soft tissue destruction, associated multilevel injury, and patient factors including advanced age and significant comorbidities. The decision requires multidisciplinary input from trauma surgery, orthopedic surgery, and vascular surgery, with patient values and preferences central to the discussion when feasible. Panel A: Hard and soft signs of vascular injury with corresponding evaluation and management pathways from immediate exploration to CT angiography. Panel B: Compartment syndrome pathophysiology showing elevated compartment pressure leading to venous obstruction, arterial insufficiency, and muscle necrosis. Panel C: Four-compartment leg fasciotomy technique with incision placement, compartment release, and wound management with negative pressure therapy. Panel D: Mangled extremity assessment factors including ischemia time, injury extent, patient factors, and decision pathway between salvage and amputation. --- ### X. Special Populations in Trauma Pediatric trauma patients present unique considerations due to anatomic and physiologic differences from adults. The relatively larger head results in higher frequency of traumatic brain injury, while the flexible thoracic cage allows significant intrathoracic injury without rib fractures. The proportionally larger body surface area predisposes to rapid heat loss and hypothermia. Vital sign normals vary by age, with higher heart rates and lower blood pressures acceptable in younger children. Solid organ injury management follows similar principles to adults with even stronger preference for nonoperative management given excellent healing capacity. Nonaccidental trauma must be considered when injury patterns are inconsistent with reported mechanism, and mandatory reporting requirements apply. Geriatric trauma patients have altered physiological responses that may mask severity of injury and delay recognition of shock. Decreased cardiac reserve limits the tachycardic response to hemorrhage, potentially maintaining normal heart rate despite significant blood loss. Chronic antihypertensive medications may blunt hypertensive response, with normal blood pressure actually representing relative hypotension in a chronically hypertensive patient. Anticoagulant and antiplatelet medications increase bleeding risk and complicate management of traumatic brain injury, where early reversal of anticoagulation may prevent hematoma expansion. Frailty and decreased physiologic reserve result in higher mortality at equivalent injury severity scores compared to younger patients. Goals of care discussions should address realistic expectations and patient preferences. Pregnant trauma patients require consideration of both maternal and fetal well-being, with the fundamental principle that optimal maternal resuscitation provides the best fetal outcome. Physiologic changes of pregnancy alter interpretation of vital signs and laboratory values. Blood volume increases by approximately fifty percent, allowing significant hemorrhage before hypotension develops. Heart rate increases ten to fifteen beats per minute with decreased blood pressure in the second trimester. After twenty weeks gestation, aortocaval compression from the gravid uterus can impair venous return in the supine position, requiring left lateral tilt or manual uterine displacement during resuscitation. Kleihauer-Betke testing identifies fetomaternal hemorrhage in Rh-negative mothers requiring Rh immunoglobulin administration. Fetal monitoring with continuous cardiotocography should be initiated for viable gestations, typically greater than twenty-four weeks, once maternal stabilization has been achieved. Fetal heart rate abnormalities may provide early indication of maternal hypovolemia before maternal vital sign changes are apparent. Placental abruption represents the most common cause of fetal death in maternal trauma and may occur with relatively minor maternal injury due to shearing forces at the placental-uterine interface. Emergency cesarean delivery may be indicated for maternal hemorrhage from uterine injury, nonreassuring fetal status in a viable gestation, or perimortem cesarean section within four minutes of maternal cardiac arrest to improve maternal resuscitation and provide chance of fetal survival. Panel A: Pediatric trauma considerations including anatomic differences, age-specific vital sign ranges, and higher nonoperative management success rates for solid organ injury. Panel B: Geriatric trauma factors showing altered physiologic responses, medication effects on vital signs and coagulation, and frailty impact on outcomes. Panel C: Pregnancy physiologic changes affecting trauma assessment including blood volume expansion, heart rate increase, and aortocaval compression. Panel D: Fetal monitoring algorithm showing initiation criteria, abnormalities suggesting maternal hypovolemia or abruption, and indications for emergency cesarean delivery. --- ## Summary - The primary survey follows ABCDE sequence addressing airway, breathing, circulation, disability, and exposure with immediate intervention for life-threatening conditions - Hemorrhagic shock classification identifies four classes based on blood loss percentage with Class III and IV requiring blood transfusion - Damage control resuscitation emphasizes balanced blood product transfusion, permissive hypotension, and early reversal of the lethal triad - Life-threatening chest injuries including tension pneumothorax, massive hemothorax, and cardiac tamponade require immediate recognition and intervention during primary survey - Nonoperative management has become standard for blunt solid organ injuries in hemodynamically stable patients regardless of injury grade - Pelvic fracture hemorrhage management employs pelvic binder, preperitoneal packing, and angioembolization in multimodal approach - Damage control surgery prioritizes hemorrhage control and contamination containment with staged definitive repair after physiologic optimization - Traumatic brain injury management focuses on preventing secondary injury through maintenance of cerebral perfusion pressure and ICP control - Compartment syndrome requires emergent fasciotomy to prevent irreversible muscle and nerve ischemia - Pediatric, geriatric, and pregnant patients require modified approaches based on anatomic, physiologic, and clinical differences --- ## Key Terms | Term | Definition | |------|------------| | ATLS | Advanced Trauma Life Support systematic approach to initial trauma evaluation and management | | FAST | Focused Assessment with Sonography for Trauma bedside ultrasound evaluating for free intraperitoneal fluid | | Damage control surgery | Abbreviated initial operation prioritizing hemorrhage control and contamination containment with planned reoperation for definitive repair | | Lethal triad | Combination of acidosis, hypothermia, and coagulopathy that perpetuates hemorrhage and predicts mortality in severe trauma | | Massive transfusion protocol | Protocol for balanced blood product administration in 1:1:1 ratio of red cells, plasma, and platelets | | Tension pneumothorax | Life-threatening condition with air under pressure in pleural space causing mediastinal shift and cardiovascular collapse | | Permissive hypotension | Resuscitation strategy tolerating lower blood pressure to reduce hemorrhage until surgical control achieved | | Compartment syndrome | Elevated pressure within fascial compartment compromising tissue perfusion requiring emergent fasciotomy | | Cerebral perfusion pressure | Mean arterial pressure minus intracranial pressure, maintained above 60 to 70 mmHg to prevent secondary brain injury | | Perimortem cesarean section | Emergency cesarean delivery within four minutes of maternal cardiac arrest to improve maternal resuscitation and fetal survival | --- *This content is subject to the [MIT License](https://opensource.org/licenses/MIT). © 2024–2026 Hibbert School of Medicine.*