Trauma Surgery

01 Trauma Anatomy — Zones, Regions, & Vascular Landmarks

Trauma surgery demands rapid anatomical reasoning under pressure. Knowing regional anatomy — the zones of the neck, thoracic landmarks, abdominal quadrants and retroperitoneal zones, and vascular territories — determines the operative approach, the urgency of exploration, and the structures at risk for every mechanism of injury.

Zones of the Neck

The neck is divided into three zones based on external landmarks, each with distinct vascular, aerodigestive, and neurologic structures at risk:

Thoracic Anatomy for Trauma

The thorax is divided by the mediastinum into left and right pleural cavities, each capable of holding >2 L of blood. Key landmarks: the cardiac box (bordered by the clavicles superiorly, nipple lines laterally, and costal margin inferiorly) defines the area where penetrating wounds mandate evaluation for cardiac injury. The thoracic inlet (suprasternal notch to T1) is a zone of transition where neck vessels become mediastinal structures. The left subclavian artery arises directly from the aortic arch and courses over the lung apex. The thoracic aorta is tethered at the ligamentum arteriosum just distal to the left subclavian artery origin — this is the most common site of traumatic aortic injury from deceleration.

The intercostal neurovascular bundle runs along the inferior border of each rib in the order Vein-Artery-Nerve (VAN, from superior to inferior). This is why chest tubes and thoracentesis needles are inserted over the SUPERIOR border of the rib, and why rib fractures can cause significant intercostal bleeding. The internal mammary artery (internal thoracic artery) runs 1 cm lateral to the sternum — laceration from sternal fractures or parasternal stab wounds can cause significant hemorrhage requiring ligation.

Abdominal Regions & Organ Vulnerability

The abdomen is divided into the peritoneal cavity (intraperitoneal organs: spleen, liver, stomach, small bowel, transverse colon, sigmoid colon), the retroperitoneum (kidneys, ureters, aorta, IVC, duodenum [2nd–4th parts], pancreas, ascending and descending colon), and the pelvis (bladder, rectum, iliac vessels, uterus). The thoracoabdominal region (from the 4th intercostal space anteriorly / tip of scapula posteriorly to the costal margin) overlaps thorax and abdomen — penetrating wounds here can injure the diaphragm, liver, or spleen.

Retroperitoneal Zones

02 Trauma Physiology — Hemorrhagic Shock & the Lethal Triad

Classes of Hemorrhagic Shock (ATLS)

The Lethal Triad

The three mutually reinforcing pathologic states that drive mortality in trauma:

Resuscitation Physiology

Acute Traumatic Coagulopathy (ATC)

ATC is a distinct entity from the coagulopathy caused by dilution, hypothermia, and acidosis. It develops within minutes of injury through two main pathways: (1) tissue hypoperfusion activates thrombomodulin on endothelium → activated protein C → consumption of factors V and VIII + inhibition of PAI-1 → hyperfibrinolysis; (2) tissue factor release from injured tissue triggers the extrinsic pathway, leading to consumptive coagulopathy. ATC is present in ~25% of severely injured patients on arrival and independently predicts mortality (4x higher mortality). Detection: prolonged PT/INR on arrival, or more precisely via TEG/ROTEM showing prolonged clotting time and hyperfibrinolysis. Treatment: early MTP activation with 1:1:1 resuscitation, TXA, and minimizing crystalloid dilution.

Permissive hypotension: in penetrating torso trauma, targeting a systolic BP of 80–90 mmHg (MAP ~50 mmHg) until surgical hemorrhage control is achieved reduces re-bleeding from disrupted clots, limits dilutional coagulopathy, and improves survival. This strategy does NOT apply to TBI patients (who require MAP >80 to maintain CPP) or to blunt trauma with likely TBI. Damage control resuscitation (DCR): the overarching strategy combining permissive hypotension, limited crystalloid use, early balanced blood product transfusion (1:1:1 ratio of pRBC:FFP:platelets), early TXA, and rapid surgical hemorrhage control. The PROPPR trial (PMID: 25647203) demonstrated that 1:1:1 ratios achieved hemostasis more effectively and reduced death from exsanguination compared to 1:1:2 ratios.

Shock Index

The Shock Index (SI) = heart rate / systolic blood pressure. Normal SI = 0.5–0.7. An SI >0.9 suggests significant hemorrhage and need for transfusion. SI >1.0 is associated with high mortality and should prompt MTP activation. Modified Shock Index (MSI) = HR / MAP is more specific. The Assessment of Blood Consumption (ABC) score uses four binary variables (penetrating mechanism, SBP ≤90, HR ≥120, positive FAST) to predict MTP need — score ≥2 has good sensitivity for massive transfusion requirement.

Non-Hemorrhagic Causes of Shock in Trauma

Not all shock in trauma is hemorrhagic. The trauma surgeon must simultaneously consider and differentiate:

03 Trauma Assessment Principles & Injury Mechanisms

Mechanism of Injury

Blunt trauma accounts for ~80% of trauma in civilian settings (motor vehicle collisions, falls, assaults, pedestrian strikes). Key kinematics: frontal impact MVC — down-and-under (femur fracture, posterior hip dislocation, patellar fracture) or up-and-over (steering wheel injuries: sternal fracture, cardiac contusion, aortic transection). Lateral impact — contralateral cervical spine fracture, ipsilateral thoracic/abdominal organ injury. Ejection from vehicle has the highest mortality. Falls from height: calcaneal fractures (lover's fracture), lumbar burst fractures, bilateral wrist fractures (Colles').

Penetrating trauma: low-velocity (stab wounds) — injury limited to the wound tract; one-third rule for anterior abdominal stab wounds — approximately 1/3 do not penetrate the peritoneum, 1/3 penetrate but do not cause significant injury, 1/3 cause injury requiring repair. High-velocity (gunshot wounds) — cavitation creates a cone of tissue destruction around the permanent wound tract. The temporary cavity from a high-velocity round can be 10–25x the bullet diameter, causing distant organ injury and microvascular thrombosis. Shotgun wounds at close range (<3 meters) behave like high-velocity injuries. Military rifle rounds (5.56 mm, 7.62 mm) produce devastating temporary cavities, and fragment/tumble inside tissue creating unpredictable wound tracks.

Blast injury has four mechanisms: primary (pressure wave — tympanic membrane rupture [most common], blast lung, bowel perforation); secondary (shrapnel/debris — penetrating injuries); tertiary (body displaced by blast wave — blunt injuries, crush); quaternary (burns, inhalation, radiation, chemical exposure). Blast lung is the most common fatal primary blast injury — presents with dyspnea, hemoptysis, and "butterfly" bilateral infiltrates on CXR. Treatment is supportive; avoid positive pressure ventilation if possible (risk of air embolism through alveolar-capillary disruption).

Transfer Criteria to Trauma Center

Field triage guidelines (CDC, ACS) identify patients who benefit from Level I/II trauma center care. Step 1 (physiologic criteria): GCS <14, SBP <90, RR <10 or >29. Step 2 (anatomic criteria): penetrating injuries to head/neck/torso/extremities proximal to elbow/knee, chest wall instability or deformity (flail chest), ≥2 proximal long bone fractures, crushed/degloved/mangled extremity, amputation proximal to wrist/ankle, pelvic fracture, open/depressed skull fracture, paralysis. Step 3 (mechanism criteria): fall >20 feet (adults) or >10 feet (children), high-risk auto crash (intrusion >12 inches occupant side or >18 inches any site, ejection, death in same passenger compartment, vehicle telemetry data consistent with high risk), auto vs pedestrian/bicyclist thrown/run over or with significant impact, motorcycle crash >20 mph. Step 4 (special considerations): age >55, anticoagulants/bleeding disorders, burns, pregnancy >20 weeks, EMS provider judgment.

Predictive Indices & Triage

04 ATLS Primary Survey (ABCDE)

The ATLS primary survey is a systematic, priority-based approach to identifying and treating immediately life-threatening injuries. Each step must be completed before moving to the next, and the survey is repeated if the patient deteriorates.

05 Secondary Survey & Adjuncts

The secondary survey is a head-to-toe physical examination performed only after the primary survey is complete and the patient is hemodynamically responding to resuscitation. It includes a complete history (AMPLE: Allergies, Medications, Past medical history, Last meal, Events of the injury), detailed physical exam of every body region, and review of all imaging.

Adjuncts to the Primary Survey

ECG: all blunt chest trauma (look for arrhythmias from cardiac contusion, PEA from tamponade). Chest X-ray (portable AP): widened mediastinum (>8 cm) suggests aortic injury; hemothorax; pneumothorax; rib fractures (1st/2nd rib fractures = high-energy mechanism, evaluate for aortic/great vessel injury). Pelvic X-ray: AP pelvis in hemodynamically unstable patients with suspected pelvic fracture. Urinary catheter: monitor urine output as marker of perfusion (goal >0.5 mL/kg/hr in adults, >1 mL/kg/hr in children); contraindicated until urethral injury excluded if blood at meatus. Gastric tube: decompress the stomach, reduce aspiration risk; use orogastric (not nasogastric) if suspected basilar skull fracture.

Adjuncts to the Secondary Survey

CT scan: the definitive imaging modality in hemodynamically stable trauma patients. Pan-scan (CT head/C-spine/chest/abdomen/pelvis with IV contrast) is standard for significant mechanisms. CT angiography for suspected vascular injury. Laboratory studies: CBC, type and crossmatch (or type and screen), BMP, coagulation studies (PT/INR, PTT, fibrinogen), lactate, base deficit, ethanol level, urine drug screen, urinalysis, pregnancy test (all women of childbearing age), TEG/ROTEM if available.

06 FAST & eFAST Examination

The Focused Assessment with Sonography in Trauma (FAST) is a bedside ultrasound performed during the primary survey to detect free intraperitoneal fluid (a surrogate for hemoperitoneum). The extended FAST (eFAST) adds bilateral thoracic views to evaluate for pneumothorax and hemothorax.

FAST Windows

07 Massive Transfusion & Damage Control Resuscitation

Massive Transfusion Protocol (MTP)

Definition: transfusion of ≥10 units of pRBCs within 24 hours, or ≥4 units in 1 hour with ongoing hemorrhage. Modern MTP delivers blood products in a 1:1:1 ratio of pRBC:FFP:platelets (the PROPPR trial standard). Coolers are pre-packaged and delivered in rounds (e.g., 6 units pRBC, 6 units FFP, 1 apheresis platelet unit per round).

Tranexamic Acid (TXA) — CRASH-2 Trial

The landmark CRASH-2 trial (PMID: 20554319) demonstrated that TXA given within 3 hours of injury reduces all-cause mortality in bleeding trauma patients. Dose: 1 g IV over 10 minutes, then 1 g IV over 8 hours. Key finding: TXA given >3 hours after injury INCREASED mortality — timing is critical. TXA is an antifibrinolytic (lysine analog that blocks plasminogen binding to fibrin).

TEG/ROTEM-Guided Resuscitation

Thromboelastography (TEG) and rotational thromboelastometry (ROTEM) provide real-time, viscoelastic assessment of the entire coagulation cascade — from clot formation to fibrinolysis. They guide component therapy more precisely than standard coagulation tests (PT/INR/PTT take 30–60 min; TEG/ROTEM results available in 5–10 min).

08 Traumatic Brain Injury

Glasgow Coma Scale (GCS)

Mild TBI: GCS 13–15. Moderate TBI: GCS 9–12. Severe TBI: GCS 3–8 (requires intubation).

Types of Intracranial Hemorrhage

ICP Management (Brain Trauma Foundation Guidelines)

Normal ICP: 5–15 mmHg. Treatment threshold: ICP >22 mmHg (BTF 4th edition). Cerebral perfusion pressure (CPP) = MAP − ICP; target CPP 60–70 mmHg.

09 Cervical Spine Injury & Clearance

Clinical Clearance Rules

Common C-Spine Injury Patterns

C1 (atlas) fracture — Jefferson fracture: burst fracture from axial loading (diving into shallow water); bilateral lateral mass displacement. Stable if transverse ligament intact (ADI <3 mm adults). C2 (axis) fracture — Odontoid fractures: Type I (tip avulsion — stable), Type II (base of dens — most common, highest nonunion rate, often requires surgical fixation), Type III (extends into C2 body — usually heals with halo). Hangman's fracture: bilateral C2 pars interarticularis fracture — usually stable due to canal widening; treated with collar or halo unless significantly displaced/angulated. Subaxial injuries: facet dislocations (unilateral = rotational instability; bilateral = complete ligamentous disruption, high risk of cord injury — requires closed reduction if awake, open reduction if obtunded).

ASIA Impairment Scale (AIS)

Sacral sparing (any sensory or motor function in S4–S5 segments — perineal sensation, voluntary anal contraction, great toe flexion) distinguishes incomplete (AIS B–D) from complete (AIS A) injuries and carries a significantly better prognosis for recovery.

Spinal Cord Injury Syndromes

10 Penetrating Neck Trauma

Hard vs Soft Signs

11 Maxillofacial Trauma

Le Fort Fracture Classification

Mandible fractures are the second most common facial fracture. The mandible is a ring structure — fractures often occur in two places (analogous to pelvic ring injuries). Most common sites: condyle (36%), body (21%), angle (20%). Tongue blade bite test: patient bites down on a tongue depressor — inability to fracture it with molar teeth suggests mandibular fracture (negative predictive value ~95%). Management: closed reduction with intermaxillary fixation (wires/arch bars) for non-displaced fractures; ORIF for displaced fractures.

Orbital Fractures

Orbital blowout fracture: isolated fracture of the orbital floor (most common) or medial wall from blunt force to the globe. Clinical findings: periorbital ecchymosis, enophthalmos, infraorbital nerve hypesthesia (numbness of the cheek and upper lip), diplopia on upgaze (inferior rectus entrapment in the fracture), restricted extraocular movement. CT (coronal cuts) is diagnostic — shows fracture with herniation of orbital fat/muscle into the maxillary sinus. Indications for surgical repair (orbital floor plating or mesh): persistent diplopia after 2 weeks, enophthalmos >2 mm, or large floor defect (>50% of floor). Urgency: "white-eyed" blowout fracture in children (trapdoor fracture trapping inferior rectus — bradycardia from oculocardiac reflex) requires urgent repair within 24–48 hours.

Zygomaticomaxillary Complex (ZMC) Fractures

The tripod fracture involves three suture lines: zygomaticofrontal, zygomaticomaxillary, and zygomaticotemporal. Clinical features: cheek flattening, periorbital ecchymosis, trismus (impingement of zygomatic arch on coronoid process of mandible), step-off at the infraorbital rim, and infraorbital nerve numbness. Non-displaced fractures may be observed; displaced fractures require ORIF at 2–3 of the fracture points.

12 Pneumothorax & Hemothorax

Pneumothorax Types

Hemothorax

Blood in the pleural space — most commonly from intercostal or internal mammary vessel laceration; less commonly from lung parenchyma (usually self-limited) or great vessel/cardiac injury.

Rib Fractures

The most common thoracic injury. First and second rib fractures indicate high-energy mechanism — evaluate for aortic/great vessel injury and brachial plexus injury. Fractures of ribs 9–12 should prompt evaluation for hepatic (right) or splenic (left) injury. Mortality increases with number of ribs fractured, especially in elderly patients (mortality doubles with ≥3 rib fractures in patients >65). Pain management is critical to prevent splinting, atelectasis, and pneumonia: multimodal analgesia with acetaminophen + NSAIDs (if no contraindication) + regional anesthesia (thoracic epidural is the gold standard for multiple rib fractures; alternatives include paravertebral block, serratus anterior plane block, and erector spinae block). Incentive spirometry and early mobilization reduce pulmonary complications.

13 Cardiac Injury & Tamponade

Cardiac Tamponade

Accumulation of blood in the pericardial sac (as little as 75–100 mL acutely) compresses the heart, impairs diastolic filling, and causes obstructive shock.

Management: Pericardiocentesis (subxiphoid approach, needle directed toward left shoulder under ultrasound guidance) is a temporizing measure — removing even 15–20 mL can dramatically improve hemodynamics. Definitive treatment is operative exploration — sternotomy (preferred for anterior wounds) or left anterolateral thoracotomy (preferred in ED/resuscitative thoracotomy). Cardiac injuries are repaired with pledgeted horizontal mattress sutures (avoid coronary arteries), and lacerations near coronaries may require passage of sutures beneath the artery.

Blunt Cardiac Injury (Cardiac Contusion)

Mechanism: steering wheel impact, high-speed deceleration. The right ventricle is most commonly injured (anterior position against the sternum). Diagnosis: ECG abnormalities (new RBBB, ST changes, frequent PVCs, atrial fibrillation) + troponin elevation. Management: continuous cardiac monitoring for 24–48 hours. Complications: arrhythmias, ventricular wall rupture (rare, usually fatal), valvular injury (tricuspid most common), cardiac herniation through pericardial tear.

Penetrating Cardiac Injury — Operative Approach

The right ventricle is most commonly injured (40%) due to its anterior position, followed by the left ventricle (35%), right atrium (15%), and left atrium (5%). Most penetrating cardiac injuries present as tamponade rather than exsanguination (the pericardium contains the hemorrhage). Stab wounds have higher survival than gunshot wounds (60–80% vs 10–30%). Repair principles: anterior right ventricular lacerations are repaired with pledgeted horizontal mattress sutures of 3-0 or 4-0 Prolene. Injuries near coronary arteries require sutures placed BENEATH the artery to avoid ligation (coronary ligation can cause infarction). Atrial injuries can be controlled with a side-biting Satinsky clamp and repaired with running Prolene. Posterior cardiac injuries are accessed by elevating the apex ("cradling the heart") — this can cause profound hypotension and arrhythmias.

14 Aortic & Great Vessel Injury

Traumatic Aortic Injury (TAI)

The second leading cause of death in blunt trauma (after TBI). Mechanism: rapid deceleration (high-speed MVC, fall from height) → shearing force at points of anatomic fixation. The aortic isthmus (just distal to the left subclavian artery, at the ligamentum arteriosum) is the most common site (~90% of tears). Other sites: aortic root (usually fatal), mid-descending aorta, diaphragmatic hiatus. Most patients with complete transection die at the scene (80–90% prehospital mortality); those who survive to the hospital have a contained rupture (adventitia and mediastinal pleura tamponade the leak — "pseudoaneurysm"). Of those who arrive alive, 50% will die within 24 hours without intervention.

CXR Findings Suggestive of Aortic Injury

Widened mediastinum >8 cm (most sensitive, ~90%); loss of aortic knob contour; deviation of trachea or NG tube to the right; depression of left mainstem bronchus; left apical cap (blood tracking over lung apex); left hemothorax; 1st/2nd rib fractures. None of these are specific — CXR is a screening tool only.

15 Pulmonary & Airway Injury

Pulmonary Contusion

The most common potentially lethal chest injury. Hemorrhage and edema within the lung parenchyma from blunt force — appears on CXR/CT as a non-anatomic (non-lobar) opacity in the lung underlying the site of impact, often with rib fractures. Worsens over 24–48 hours. Management: supplemental O2, judicious fluid resuscitation (avoid fluid overload), aggressive pulmonary toilet, intubation/mechanical ventilation if PaO2/FiO2 <200 or progressive respiratory failure. Avoid over-resuscitation — third-spacing of fluid into contused lung worsens gas exchange.

Flail Chest

Defined as ≥3 consecutive ribs fractured in ≥2 places, creating a free-floating segment that moves paradoxically with respiration. The clinical significance is NOT the paradoxical motion but the underlying pulmonary contusion. Management: adequate analgesia (epidural preferred, or paravertebral/serratus anterior nerve block), aggressive pulmonary toilet, non-invasive ventilation (BiPAP), intubation if needed. Surgical rib fixation (rib plating) is increasingly used for severe flail segments — evidence suggests reduced pneumonia, shorter ventilator days, and reduced ICU stay (PMID: 23694879).

Tracheobronchial Injury

Rare but life-threatening. Suspect when: large, persistent air leak through chest tube; pneumomediastinum; subcutaneous emphysema; failure of the lung to fully re-expand after tube thoracostomy. Most injuries occur within 2.5 cm of the carina. Diagnosis: bronchoscopy. Management: small tears (<1/3 circumference) without respiratory compromise may heal with conservative management (selective intubation past the injury); large tears require operative repair via thoracotomy.

Diaphragmatic Injury

Left-sided injury more common (3:1) — the liver protects the right hemidiaphragm. Blunt mechanism causes large radial tears; penetrating causes small perforations that may enlarge over time. CXR findings: elevated hemidiaphragm, NG tube coiled in the chest, bowel gas pattern above the diaphragm. CT sensitivity is ~60–80% (can miss small injuries). Diagnosis may require diagnostic laparoscopy or thoracoscopy. All diaphragmatic injuries require operative repair — primary closure with interrupted non-absorbable sutures (polypropylene or nylon) in blunt trauma; laparoscopic repair may be appropriate for small, penetrating injuries found incidentally.

16 Resuscitative Thoracotomy

Indications

Technique

The standard approach is a left anterolateral thoracotomy in the 4th or 5th intercostal space, from the sternum to the posterior axillary line. Steps:

1. Incision: Left anterolateral thoracotomy through the 4th/5th intercostal space. Extend across the sternum to the right chest ("clamshell") if needed for bilateral access.
2. Open pericardium: longitudinal incision ANTERIOR to the phrenic nerve → evacuate blood/clot → repair cardiac laceration with pledgeted 3-0 Prolene horizontal mattress sutures (or digital occlusion / Foley catheter balloon tamponade as temporizing measures).
3. Cross-clamp the descending thoracic aorta: retract the left lung anteriorly and superiorly → identify the descending aorta against the spine → apply a large vascular (Satinsky) clamp. This redistributes blood flow to the heart and brain and controls subdiaphragmatic hemorrhage.
4. Internal cardiac massage: bimanual (two-hand) technique, compressing from apex to base toward the sternum.
5. Control pulmonary hilum: twist and clamp the hilum (hilar twist) to control massive pulmonary hemorrhage or air embolism.

17 Splenic Injury

AAST Spleen Injury Scale

Nonoperative Management (NOM)

Post-Splenectomy Considerations

Splenectomy creates lifelong risk of overwhelming post-splenectomy infection (OPSI) — fulminant sepsis from encapsulated organisms (Streptococcus pneumoniae, Haemophilus influenzae, Neisseria meningitidis). Mortality of OPSI is 50–70%. Vaccinate ≥14 days post-splenectomy (or pre-discharge if the patient may not follow up): pneumococcal (PCV20 or PCV15 + PPSV23), meningococcal (MenACWY + MenB), Hib. Patients should carry a medical alert card and receive early antibiotics for any febrile illness.

18 Liver Injury

AAST Liver Injury Scale

Operative Techniques for Hepatic Hemorrhage

Pringle maneuver: manual or vascular clamp compression of the hepatoduodenal ligament (portal triad — hepatic artery + portal vein + common bile duct) to temporarily control hepatic inflow. Safe for intermittent clamping (15–20 min on, 5 min off). If bleeding stops with Pringle → source is hepatic artery or portal vein (inflow). If bleeding continues → source is hepatic vein or retrohepatic IVC (outflow).

Perihepatic packing: the cornerstone of damage control for liver hemorrhage. Laparotomy pads placed above and below the liver, compressing the liver between the diaphragm and packs. Effective for controlling venous hemorrhage and parenchymal oozing. Leave packs in place, perform temporary abdominal closure, resuscitate in ICU, and return to OR in 24–48 hours for pack removal and definitive repair.

Finger fracture technique: for deep lacerations, the surgeon can digitally fracture hepatic parenchyma along the line of injury to expose bleeding vessels and bile ducts for individual ligation — the hepatic parenchyma is friable but vessels/ducts are more resistant and remain intact for identification and ligation.

Additional techniques: direct suture hepatorrhaphy (horizontal mattress with large chromic/Vicryl suture for simple lacerations), topical hemostatic agents (fibrin sealant, Surgicel, thrombin-soaked Gelfoam), hepatic artery ligation (right or left — the liver tolerates hepatic artery ligation due to dual blood supply, but carries risk of biliary necrosis), resectional debridement (non-anatomic resection of devitalized tissue), and in extreme cases, total hepatic vascular isolation (Pringle + suprahepatic and infrahepatic IVC clamping — extremely poorly tolerated hemodynamically).

19 Hollow Viscus & Mesenteric Injury

Small Bowel Injury

The most commonly injured hollow viscus in penetrating abdominal trauma. In blunt trauma, small bowel injuries are uncommon (~5% of laparotomies for blunt trauma) but easily missed — the CT finding of free intraperitoneal fluid WITHOUT solid organ injury should raise high suspicion. Mechanism in blunt trauma: compression against the spine (especially the fixed duodenojejunal junction at the ligament of Treitz and the distal ileum at the ileocecal valve), or mesenteric tearing with bowel devascularization. CT signs: bowel wall thickening, mesenteric stranding/hematoma, extraluminal air, free fluid without solid organ injury. Management: simple lacerations → primary repair (single or double layer); extensive injury or devascularized segments → segmental resection with anastomosis. In damage control situations, bowel is stapled off (not anastomosed) and left in discontinuity for second-look.

Colon Injury

Primary repair is appropriate for most colon injuries, including in the setting of penetrating trauma — the older practice of mandatory diversion (colostomy) for all colon injuries has been largely abandoned based on multiple prospective studies. Indications for diversion (colostomy): delayed diagnosis (>12 hours), massive fecal contamination, damage control setting, destructive rectal injuries, hypotension requiring vasopressors, or large colon tissue loss requiring tenuous anastomosis. Extraperitoneal rectal injuries: presacral drainage and proximal diversion remain standard.

Gastric Injury

The stomach is relatively protected by the rib cage but can be injured by penetrating trauma (GSW, stab wound) or severe blunt force (full stomach rupture on impact). Most gastric injuries are found during laparotomy for other indications. Management: debridement of devitalized tissue → primary two-layer repair (inner running absorbable, outer interrupted seromuscular Lembert sutures). Always inspect BOTH the anterior and posterior walls — a through-and-through injury requires opening the lesser sac (dividing the gastrocolic ligament) to inspect the posterior stomach wall. Missed posterior gastric wall injuries are a classic pitfall.

Mesenteric Injury

Mesenteric hematomas may compromise bowel blood supply even without direct bowel wall injury. Operative management: inspect the mesenteric border for any compromised bowel (dusky, non-peristaltic, non-bleeding from cut edges → resect). Control mesenteric hemorrhage with suture ligation. Avoid ligating the SMA or large mesenteric branches — loss of significant mesenteric vasculature may require resection of the affected bowel segment. The "seatbelt sign" (ecchymosis across the abdominal wall from a lap belt) is associated with a 5–10x higher incidence of bowel and mesenteric injury — maintain a high index of suspicion in these patients and have a low threshold for CT or even diagnostic laparoscopy.

20 Pancreatic & Duodenal Injury

Pancreatic Injury

Uncommon (~2% of abdominal trauma) but high morbidity. Mechanism: blunt epigastric force compressing the pancreas against the spine (classically, bicycle handlebar injury in children, steering wheel in adults, or assault). The key determinant of management is ductal integrity.

Ductal assessment: MRCP (non-invasive, preferred in stable patients), ERCP (diagnostic and therapeutic — stenting for small ductal disruptions), or intraoperative assessment (transection visible, or intraoperative secretin injection with ductal cannulation). CT findings suggestive of pancreatic injury: pancreatic laceration/transection (often subtle), peripancreatic fluid, fluid between the splenic vein and the pancreas (separating the pancreas from its retroperitoneal bed), and thickening of the left anterior renal fascia. CT sensitivity for pancreatic injury is only ~60–80%, especially in the first 12 hours — maintain a high index of suspicion with handlebar or seatbelt mechanism injuries.

Duodenal Injury

Most duodenal injuries result from penetrating trauma. Blunt injuries are uncommon but easily missed. Management depends on location and severity:

Simple lacerations (<50% circumference, no devascularization): primary repair in two layers (inner absorbable, outer seromuscular). Complex injuries (>50% circumference, devascularized, or delayed diagnosis): Roux-en-Y duodenojejunostomy (serosal patch for small defects), pyloric exclusion (close pylorus from inside with absorbable suture + gastrojejunostomy — pylorus reopens spontaneously in 2–3 weeks), or rarely pancreaticoduodenectomy (Whipple) for combined severe pancreatic head and duodenal injuries. Duodenal hematoma (intramural, typically from blunt trauma in children): usually resolves with nasogastric decompression and TPN over 1–3 weeks; operates only if obstruction persists beyond 2–3 weeks or if exploration is required for other reasons.

21 Renal & Urologic Trauma

AAST Kidney Injury Scale

Nonoperative management is successful in >90% of blunt renal injuries (grades I–IV). CT with delayed images (10-min delay) assesses collecting system integrity and urinary extravasation. Renal artery thrombosis from blunt deceleration has a very narrow window for revascularization (<4–6 hours of warm ischemia); beyond this, nephrectomy or observation (if contralateral kidney is normal) is preferred.

Ureteral Injury

Rare in trauma (most are iatrogenic from surgery). If identified operatively: simple laceration → primary repair over a stent; complete transection → debridement of devitalized tissue + spatulated, tension-free, stented reanastomosis. Distal ureteral injury → ureteroneocystostomy (reimplantation into the bladder with a psoas hitch or Boari flap for length). Mid-ureteral loss → transureteroureterostomy or ileal interposition graft.

Bladder Injury

Extraperitoneal rupture (80%): associated with pelvic fractures; managed with Foley catheter drainage alone for 10–14 days; heals spontaneously in >95%. Intraperitoneal rupture (20%): results from blunt force to a full bladder (seatbelt injury); requires operative repair — two-layer closure with absorbable suture + Foley drainage. If bladder injury is found during laparotomy for other indications, repair both types operatively. Diagnosis: retrograde cystogram (instill at least 350 mL contrast via Foley, obtain filled and post-drainage films) or CT cystogram. Gross hematuria with pelvic fracture is an absolute indication for cystography.

Urethral Injury

Suspect in males with pelvic fractures. Classic triad: blood at the urethral meatus, perineal/scrotal ecchymosis ("butterfly hematoma"), and high-riding or non-palpable prostate on DRE. Do NOT insert a Foley catheter until urethral injury is excluded by retrograde urethrogram (RUG). Posterior urethral injury (membranous urethra, above the urogenital diaphragm): associated with pelvic fractures; initial management = suprapubic catheter placement; definitive repair (urethroplasty) delayed 3–6 months. Anterior urethral injury (bulbar/penile urethra, below the urogenital diaphragm): straddle injuries; may be managed with primary alignment over a catheter or delayed repair. A single gentle attempt at Foley placement is acceptable if blood at the meatus is absent and clinical suspicion is low, but any resistance mandates RUG.

22 Retroperitoneal Hematoma

Retroperitoneal hematomas (RPH) found during trauma laparotomy require a zone-based management strategy (see Section 01 for zone anatomy).

23 Peripheral Vascular Injury

Hard vs Soft Signs of Vascular Injury

Ankle-Brachial Index (ABI): ratio of ankle SBP to brachial SBP measured by Doppler. ABI <0.9 = abnormal, requires CTA or operative exploration. ABI >0.9 in an asymptomatic patient with soft signs has a negative predictive value >99% for clinically significant vascular injury.

Vascular Repair Principles

Obtain proximal and distal vascular control before entering a hematoma. Options for repair: lateral arteriorrhaphy (for small lacerations — ensure no stenosis >50%); patch angioplasty (for larger lacerations that would stenose with primary repair); end-to-end anastomosis (for transections with <2 cm gap after debridement); interposition graft (autologous reversed saphenous vein preferred; PTFE if vein unavailable or for large-caliber vessels); temporary vascular shunt (Argyle, Javid, or Pruitt-Inahara shunt — used in damage control to restore distal flow while other life-threatening injuries are addressed or the patient is transferred). Shunts are secured with silk ties and can remain patent for 24–48 hours.

Mangled Extremity Severity Score (MESS)

*Score doubled if ischemia time >6 hours. MESS ≥7 has historically predicted the need for amputation with high specificity, though it should not be used as the sole determinant — modern microsurgery and free tissue transfer have salvaged limbs with high MESS scores. The LEAP trial (PMID: 12473698) showed similar long-term functional outcomes between reconstruction and amputation for severe lower extremity injuries.

24 Compartment Syndrome & Fasciotomy

Pathophysiology

Elevated pressure within a closed fascial compartment compromises tissue perfusion, leading to ischemia and necrosis of muscle and nerve. Ischemic time >6 hours causes irreversible damage. Common causes: fractures (tibial shaft most common), crush injuries, vascular injury with ischemia-reperfusion, tight circumferential dressings/casts, burns, massive fluid resuscitation.

Diagnosis

The 6 P's (pain, pressure, paresthesias, paralysis, pallor, pulselessness) — but pain out of proportion to injury and pain with passive stretch of the compartment muscles are the earliest and most sensitive clinical findings. Loss of pulses is a LATE finding — do not wait for this. In obtunded patients, measure compartment pressures with a Stryker pressure monitor: absolute pressure >30 mmHg or delta pressure (diastolic BP minus compartment pressure) <30 mmHg is the threshold for fasciotomy (delta pressure is more reliable than absolute pressure).

Four-Compartment Lower Leg Fasciotomy

25 Pelvic Fractures & Hemorrhage Control

Classification (Young-Burgess)

Hemorrhage Control Algorithm

26 Orthopedic Trauma Principles

Gustilo-Anderson Classification of Open Fractures

Antibiotic Prophylaxis for Open Fractures

Based on the EAST guidelines: Type I–II: first-generation cephalosporin (cefazolin 2 g IV q8h) for 24 hours. Type III: add an aminoglycoside (gentamicin 5 mg/kg IV q24h) for 72 hours or until soft tissue coverage. Farm/soil contamination: add penicillin G (for Clostridium). All patients: verify tetanus prophylaxis status.

Damage Control Orthopedics (DCO)

In polytrauma patients who cannot tolerate definitive fixation (hemodynamically unstable, coagulopathic, hypothermic, head injury), temporary external fixation of long bone fractures is performed to achieve skeletal stability without the "second hit" of prolonged definitive surgery. External fixators are converted to intramedullary nails or plates when the patient stabilizes (typically 5–10 days). Early Total Care (ETC) — definitive fixation within 24 hours — is appropriate for isolated long bone fractures in hemodynamically stable patients, particularly femoral shaft fractures (early fixation reduces pulmonary complications and ICU stay).

Traumatic Amputations

Management in the field: tourniquet application proximal to the amputation (leave in place until operative control), pressure dressing on the stump, wrap the amputated part in saline-moistened gauze → place in plastic bag → place on ice (NOT directly on ice — avoid freezing). Replantation criteria (consider for): thumb amputation, multiple digit amputations, mid-hand or more proximal amputations in adults, almost any level in children. Sharp amputations (clean-cut) have better replantation success than crush/avulsion amputations. Warm ischemia time limit: ~6 hours for digits, ~4 hours for major limbs. Cold ischemia tolerance: ~12 hours for digits, ~6 hours for major limbs.

Traumatic Joint Dislocations

Hip dislocation: 90% posterior (dashboard injury — flexed, adducted, internally rotated hip). Reduce within 6 hours to minimize risk of avascular necrosis (AVN) of the femoral head. Sciatic nerve injury in 10%. Knee dislocation: emergency — popliteal artery injury in 30–40% of cases. After reduction, mandatory ABI measurement: ABI <0.9 → CTA or surgical exploration. Even with normal ABI, serial vascular exams for 24–48 hours are required (intimal injuries may thrombose with delayed occlusion). Multi-ligament knee injury (ACL + PCL ± collaterals) requires vascular assessment regardless of dislocation status.

27 Damage Control Laparotomy

Indications for Damage Control

Abbreviated Laparotomy Technique

The damage control laparotomy follows a strict protocol of rapid hemorrhage control and contamination control, without definitive repair:

1. Midline laparotomy: full xiphoid-to-pubis incision.
2. Four-quadrant packing: pack all four quadrants with laparotomy pads → temporary hemorrhage control → systematic inspection.
3. Hemorrhage control: perihepatic packing for liver injuries; splenectomy for severe splenic injury; vascular clamping or shunting for major vessel injuries; ligation of smaller vessels.
4. Contamination control: staple across bowel injuries (GIA stapler) — do NOT perform anastomosis; temporarily close bowel ends with suture or stapler. Drain bile/urine if bile duct or bladder injury identified.
5. Temporary abdominal closure: do NOT attempt fascial closure (risk of abdominal compartment syndrome). Apply negative pressure wound therapy (Barker vacuum pack or commercial VAC system) or use a Bogota bag (sterile IV bag sewn to skin edges).
6. Transfer to ICU for damage control resuscitation.

Total OR time for abbreviated laparotomy should be <60–90 minutes. "You can stop anytime" — if the patient deteriorates, the surgeon should progress to closure immediately.

28 ICU Resuscitation & Planned Reoperation

ICU Phase Goals

The ICU phase of damage control focuses on correcting the lethal triad before returning to the OR:

Planned Reoperation

Return to OR typically within 24–48 hours once the lethal triad is corrected. At reoperation: remove packing (soak with warm saline before removal to minimize re-bleeding), reassess bowel viability (resect any non-viable segments), perform definitive bowel anastomosis or stoma creation, perform definitive vascular repair (remove shunts, complete grafting), irrigate thoroughly, and attempt fascial closure if possible.

29 Open Abdomen Management

Temporary Abdominal Closure Techniques

Sequential Fascial Closure

The goal is primary fascial closure at the earliest safe opportunity. With each return to OR, the fascia is serially advanced (tightening the NPWT system or Wittmann patch). Fascial closure rates with NPWT are 60–80% when closure is achieved within 7–10 days. After 10–14 days, progressive loss of fascial domain makes primary closure increasingly difficult — the fascial edges retract laterally and the abdominal wall musculature shortens. If primary closure cannot be achieved, the abdomen is managed as a planned ventral hernia: NPWT continued until granulation tissue covers the viscera → split-thickness skin graft over granulation tissue → delayed ventral hernia repair (6–12 months after skin grafting, once the patient has fully recovered).

Techniques to facilitate delayed closure: component separation (external oblique release), progressive pneumoperitoneum (daily insufflation of air into the peritoneal cavity to stretch the abdominal wall and recover fascial domain), and biologic mesh bridging (porcine or human acellular dermal matrix placed as a bridge between fascial edges — vascularizes and incorporates, providing a scaffold for tissue ingrowth, though long-term hernia rates remain high).

30 Burn Assessment & Fluid Resuscitation

Burn Depth Classification

Total Body Surface Area (TBSA) Estimation

Rule of Nines (adults): head/neck = 9%; each upper extremity = 9%; anterior trunk = 18%; posterior trunk = 18%; each lower extremity = 18%; perineum = 1%. Lund-Browder chart: more accurate, especially in children (adjusts for proportional differences — e.g., an infant's head is 18% TBSA vs 9% in adults). Palmar method: the patient's palm (including fingers) ≈ 1% TBSA — useful for small or scattered burns. Only include partial-thickness and full-thickness burns in TBSA calculation for fluid resuscitation (superficial burns are excluded).

Fluid Resuscitation — Parkland Formula

Escharotomy

Circumferential full-thickness burns create a non-elastic eschar that, as underlying tissue swells, can cause compartment syndrome of the extremity or restrict chest wall excursion (respiratory compromise). Indications: circumferential extremity burns with diminished pulses, poor capillary refill, or elevated compartment pressures; circumferential chest burns with impaired ventilation. Technique: full-thickness incision through eschar only (not into subcutaneous fat) along the medial and lateral mid-axial lines of extremities or along the anterior axillary lines of the chest. No anesthesia required (the eschar is insensate). Bleeding is usually minimal (full-thickness burns destroy dermal vasculature).

Burn Center Transfer Criteria (ABA)

Partial-thickness burns >10% TBSA; burns involving face, hands, feet, genitalia, perineum, or major joints; full-thickness burns of any size; electrical/chemical burns; inhalation injury; burns in patients with significant comorbidities; burns with concomitant trauma (where burn is the greatest risk); children in facilities without qualified pediatric burn capabilities.

Electrical Burns

Low voltage (<1000 V): primarily causes cutaneous thermal burns at entry/exit sites. High voltage (≥1000 V): current travels through tissues of least resistance (nerves, blood vessels, muscle) causing deep tissue destruction far exceeding the visible surface burn. Complications: rhabdomyolysis (aggressive IV fluids to maintain UOP >1–2 mL/kg/hr; alkalinize urine if myoglobinuria), cardiac arrhythmias (ECG monitoring for 24 hours — high voltage, loss of consciousness, or abnormal initial ECG), compartment syndrome (fasciotomy often required), and delayed neurologic deficits (transverse myelitis, peripheral neuropathy). Lightning injury: direct strike, side flash, ground current; cardiac arrest from asystole (often reversible with CPR, unlike VFib in other settings — "reverse triage" — treat the apparently dead first).

Chemical Burns

Treatment principle: copious water irrigation for at least 20–30 minutes — begin immediately. Remove all contaminated clothing. Do NOT attempt neutralization (exothermic reaction worsens injury). Specific agents: hydrofluoric acid (HF) — uniquely dangerous; fluoride ion penetrates tissue and chelates calcium, causing severe hypocalcemia, cardiac arrhythmias (QT prolongation), and progressive deep tissue necrosis. Treatment: topical calcium gluconate gel (2.5%) to the affected area; for significant exposures, intradermal or intra-arterial calcium gluconate injection; monitor serum calcium and ECG. Alkali burns (cement, lye, oven cleaners) cause liquefactive necrosis — deeper penetration than acid burns (coagulative necrosis with acid creates a protective eschar). Irrigate extensively.

31 Inhalation Injury, Hypothermia, & Frostbite

Inhalation Injury

Three components: supraglottic thermal injury (heat is efficiently dissipated by the oropharynx — direct thermal injury is rare below the glottis unless steam exposure); lower airway chemical injury (combustion products — acrolein, aldehydes, HCl — cause mucosal edema, bronchospasm, mucosal sloughing); systemic toxicity (carbon monoxide [CO] and cyanide [HCN]). Suspect inhalation injury with: facial burns, singed nasal hairs/eyebrows, soot in oropharynx/sputum, hoarseness, stridor, history of enclosed-space fire. Diagnosis confirmed by fiberoptic bronchoscopy (mucosal edema, erythema, carbonaceous deposits, ulceration). Management: early intubation (airway edema progresses rapidly — intubate prophylactically if signs of impending obstruction), aggressive pulmonary toilet, bronchodilators.

Carbon monoxide poisoning: CO has 200–250x greater affinity for hemoglobin than oxygen → carboxyhemoglobin (COHb) shifts the oxyhemoglobin dissociation curve left → tissue hypoxia. Pulse oximetry is falsely normal (reads COHb as O2Hb). Diagnosis: co-oximetry on ABG. Treatment: 100% FiO2 via NRB or mechanical ventilation (half-life of COHb: room air = 5 hours; 100% O2 = 60–90 min; hyperbaric O2 = 20–30 min). Hyperbaric O2 is indicated for COHb >25%, LOC, pregnancy, or end-organ dysfunction. Cyanide poisoning: suspect in enclosed-space fire victims with persistent lactic acidosis despite normal PaO2. Treatment: hydroxocobalamin 5 g IV (Cyanokit) — first-line; binds cyanide directly. Alternative: sodium thiosulfate.

Hypothermia

Frostbite

Classified by depth: 1st degree (superficial — erythema, edema, no blisters → full recovery); 2nd degree (partial-thickness — clear blisters, erythema → usually heals); 3rd degree (full-thickness — hemorrhagic blisters, skin necrosis); 4th degree (extends to muscle/bone — mummification, likely amputation). Treatment: rapid rewarming in 37–39 C water bath for 15–30 minutes (do NOT use dry heat, do NOT rub). TPA within 24 hours may improve limb salvage in severe frostbite with absent flow on angiography. Do NOT debride early — "frostbite in January, amputate in July" (allow complete demarcation before definitive surgery).

32 Chest Tube, Cricothyroidotomy, & DPL

Chest Tube Thoracostomy

Indication: pneumothorax (symptomatic or tension), hemothorax, post-thoracotomy. Position: 4th or 5th intercostal space, anterior to mid-axillary line, in the "safe triangle" (anterior border of latissimus dorsi, lateral border of pectoralis major, horizontal line at nipple level, apex of axilla). Size: 28–32 Fr for hemothorax; 24–28 Fr for pneumothorax. Technique: 2–3 cm skin incision over the rib below the target intercostal space → blunt dissection with Kelly clamp over the TOP of the rib (avoids the intercostal neurovascular bundle on the inferior rib margin) → puncture the parietal pleura → finger sweep to confirm entry into pleural space and sweep for adhesions → direct tube posteriorly and superiorly (for hemothorax drainage) → connect to water seal (−20 cm H2O) → secure with suture → CXR to confirm position. Document initial output volume.

Surgical Cricothyroidotomy

Indication: "can't intubate, can't oxygenate" scenario. Contraindicated in children <12 (use needle cricothyroidotomy). Technique: palpate the cricothyroid membrane (between thyroid cartilage and cricoid cartilage — the most accessible and avascular area of the airway). Stabilize the larynx. Horizontal stab incision through skin and membrane → insert tracheal hook to maintain airway → dilate with hemostats or Trousseau dilator → insert cuffed tracheostomy tube (6.0) or cuffed ETT (6.0). Surgical cricothyroidotomy should be converted to formal tracheostomy within 24–72 hours if prolonged airway is needed.

Diagnostic Peritoneal Lavage (DPL)

Largely replaced by FAST and CT, but remains useful when ultrasound is unavailable or equivocal in unstable patients. Technique: decompress the stomach (NG tube) and bladder (Foley). Open (infraumbilical or supraumbilical if pelvic fracture) or Seldinger technique. Aspirate: grossly positive if >10 mL of gross blood (→ laparotomy). If not grossly positive, infuse 1 L warm LR (10 mL/kg in children) → drain by gravity → send for lab analysis. Positive lavage criteria: RBC >100,000/mm3 (blunt) or >5,000/mm3 (penetrating); WBC >500/mm3; amylase >175 IU/dL; bacteria or bile on Gram stain; food particles. DPL is very sensitive (~98%) but not specific — it detects ANY intra-abdominal blood and does not grade injuries or guide nonoperative management.

33 REBOA

Resuscitative Endovascular Balloon Occlusion of the Aorta

REBOA is an endovascular adjunct for temporary aortic occlusion to control non-compressible torso hemorrhage (NCTH), serving as a less-invasive alternative to resuscitative thoracotomy with aortic cross-clamp.

Technique: Common femoral artery access (ultrasound-guided, 7 Fr sheath). Advance balloon catheter (ER-REBOA catheter) to the appropriate zone under fluoroscopic guidance (or using external landmarks). Inflate balloon until loss of contralateral femoral pulse (Zone I) or until blood pressure response. Partial REBOA (partial inflation) may reduce ischemia-reperfusion injury. Complications: aortic injury, iliac/femoral injury, distal ischemia, balloon migration, ischemia-reperfusion injury on deflation (hyperkalemia, lactic acidosis, cardiac arrest). Time limit: Zone I inflation should be <60 minutes; Zone III <90 minutes. Transition to definitive care as rapidly as possible.

REBOA vs Resuscitative Thoracotomy

34 Fasciotomy Techniques

Fasciotomy technique for the four-compartment lower leg release is detailed in Section 24. Additional fasciotomy sites:

Forearm Fasciotomy

Volar (flexor) compartment: curvilinear incision from proximal to the medial epicondyle, crossing the antecubital fossa, extending distally along the ulnar aspect of the forearm to the wrist, then crossing into the palm (carpal tunnel release). Release the lacertus fibrosus, flexor-pronator mass, and carpal tunnel. Dorsal (extensor) compartment: straight longitudinal incision over the mobile wad (lateral forearm). The mobile wad (brachioradialis, ECRL, ECRB) lies between the volar and dorsal compartments.

Thigh Fasciotomy

Three compartments: anterior (quadriceps), medial (adductors), posterior (hamstrings). Lateral incision from the greater trochanter to the lateral femoral condyle releases the anterior and posterior compartments through the lateral intermuscular septum. A separate medial incision is used for the medial compartment.

Foot Fasciotomy

Nine compartments in the foot. Two dorsal incisions (medial: over the 2nd metatarsal; lateral: over the 4th metatarsal) access interosseous and adductor compartments. A medial incision posterior to the medial malleolus accesses the calcaneal compartment. Most commonly performed for crush injuries or calcaneal fractures.

Prophylactic Fasciotomy Indications

Fasciotomy should be performed prophylactically (before clinical compartment syndrome develops) in the following high-risk situations: combined arterial and venous injury with >4–6 hours of ischemia before revascularization; crush injury with prolonged entrapment (>4 hours); massive fluid resuscitation (≥6 L crystalloid); high-velocity injury with significant soft tissue destruction; and after repair of any popliteal artery injury (prophylactic 4-compartment fasciotomy is recommended by many surgeons given the high rate of subsequent compartment syndrome). Delayed fasciotomy (>8 hours after onset of compartment syndrome) carries a high risk of infection and should be balanced against the likelihood of non-viable muscle requiring debridement.

35 Blood Products & Tranexamic Acid

Blood Product Overview

Tranexamic Acid (TXA) — Detailed

Mechanism: synthetic lysine analog that competitively inhibits plasminogen activation → prevents fibrinolysis → stabilizes clot. Dose: 1 g IV bolus over 10 min (within 3 hours of injury) → 1 g IV infusion over 8 hours. Key evidence: CRASH-2 (PMID: 20554319) — 1.5% absolute mortality reduction when given within 3 hours; TXA >3 hours INCREASED mortality. CRASH-3 (TBI) — modest benefit in mild-to-moderate TBI when given early; no benefit in severe TBI with GCS 3–8. MATTERs study (military) — TXA + MTP associated with 6.5% absolute mortality reduction. Contraindications: time >3 hours from injury, active thromboembolic disease, DIC with predominant thrombosis.

36 Reversal Agents, Vasopressors, & Adjuncts

Anticoagulant Reversal Agents

Vasopressors in Trauma

Volume resuscitation is the first-line treatment for hemorrhagic shock. Vasopressors are used as a bridge while hemorrhage control and blood product resuscitation are ongoing — they are NOT a substitute for volume.

Additional Adjuncts

Tetanus prophylaxis: all trauma patients with wounds — give Td/Tdap if last dose >5 years ago; add TIG (tetanus immune globulin 250 U IM) if unknown vaccination history or <3 prior doses. Antibiotics for open fractures: see Section 26. VTE prophylaxis: all trauma patients are at high risk for DVT/PE. Start LMWH (enoxaparin 30 mg SC q12h) as early as safe — within 24–48 hours for most injuries (hold for active hemorrhage, intracranial hemorrhage, incomplete spinal cord injury, or high-grade solid organ injury with active blush). Mechanical prophylaxis (SCDs) from admission. IVC filter placement only if VTE prophylaxis is contraindicated for >72 hours AND high-risk features present. Dose adjustments: consider enoxaparin 40 mg SC q12h in obese patients (>120 kg) — measure anti-Xa levels (target 0.2–0.4 IU/mL for prophylaxis). Unfractionated heparin 5000 U SC q8h is an alternative in patients with CrCl <30 mL/min.

Stress ulcer prophylaxis: indicated in mechanically ventilated patients, coagulopathic patients, and those with TBI, burns >35% TBSA, or spinal cord injury. Proton pump inhibitors (pantoprazole 40 mg IV daily) or H2 blockers (famotidine 20 mg IV q12h). Transition to enteral PPI when tolerating feeds. Discontinue when risk factors resolve.

Nutritional support: early enteral nutrition (within 24–48 hours) is strongly recommended in trauma patients. Trophic feeds (10–20 mL/hr) via nasogastric or post-pyloric tube should be started as soon as resuscitation is complete. Goals: 25–30 kcal/kg/day, 1.5–2 g protein/kg/day (trauma patients are hypermetabolic/hypercatabolic). Parenteral nutrition is reserved for patients who cannot tolerate enteral feeds for >7 days. Open abdomen patients present a unique challenge — enteral feeding is still recommended (jejunal access preferred) and is safe even with exposed bowel, provided there is intestinal continuity.

37 Classification Systems (All)

AAST Organ Injury Scales — Summary

AAST grading for spleen (Section 17), liver (Section 18), kidney (Section 21), and pancreas (Section 20) are detailed in their respective sections. The grading system (I–V or I–VI) is universally used for operative decision-making and reporting.

Glasgow Coma Scale

Detailed in Section 08. Range: 3–15. Severe TBI ≤8, moderate 9–12, mild 13–15.

Hemorrhagic Shock Classes (ATLS)

Detailed in Section 02. Classes I–IV based on estimated blood loss and physiologic parameters.

Gustilo-Anderson Classification

Detailed in Section 26. Types I, II, IIIA, IIIB, IIIC for open fractures.

MESS (Mangled Extremity Severity Score)

Detailed in Section 23. Score ≥7 historically predictive of amputation.

AAST Organ Injury Scale — Diaphragm

Additional Classification Systems

38 Complications — Missed Injury, ACS, ARDS, & DVT/PE

Missed Injury

Missed injury rate in major trauma: 2–10%. Most commonly missed: thoracolumbar spine fractures, small pneumothoraces, extremity fractures (especially in obtunded/intubated patients), hollow viscus injuries (CT sensitivity for bowel injury is only ~90%), diaphragmatic tears (especially small penetrating injuries to the left diaphragm), and peripheral nerve injuries.

Abdominal Compartment Syndrome (ACS)

Sustained intra-abdominal pressure (IAP) >20 mmHg with new organ dysfunction. Normal IAP: 5–7 mmHg. Measured via bladder pressure transduction (instill 25 mL saline into Foley → measure pressure at end-expiration). Causes in trauma: massive fluid resuscitation, retroperitoneal hemorrhage, visceral edema, tight abdominal closure.

ARDS (Acute Respiratory Distress Syndrome)

Berlin Definition: acute onset (within 1 week of insult), bilateral opacities on CXR (not fully explained by effusions/atelectasis), respiratory failure not fully explained by cardiac failure, PaO2/FiO2 ratio: mild 200–300, moderate 100–200, severe <100 (on PEEP ≥5). Common causes in trauma: pulmonary contusion, aspiration, massive transfusion (TRALI), sepsis, fat embolism. Management: lung-protective ventilation (tidal volume 6 mL/kg ideal body weight, plateau pressure <30 cm H2O — ARDSNet protocol), PEEP titration, prone positioning for moderate-severe ARDS (PROSEVA trial — PMID: 23688302), conservative fluid strategy (FACTT trial), and neuromuscular blockade in severe cases.

DVT/PE

Trauma patients are at very high risk for VTE due to Virchow's triad: stasis (immobilization, pelvic/lower extremity fractures), endothelial injury (vascular trauma, surgery), and hypercoagulability (acute phase response, blood product transfusion). Prophylaxis: LMWH (enoxaparin 30 mg SC q12h) started as early as safely possible + mechanical compression devices. Screening duplex ultrasound is debated — some centers screen all high-risk patients before mobilization. Treatment of confirmed DVT/PE: therapeutic anticoagulation (heparin drip → transition to LMWH or DOAC). Massive PE with hemodynamic instability → thrombolysis (alteplase), catheter-directed therapy, or surgical thrombectomy.

Fat Embolism Syndrome

Classic triad: respiratory distress, neurologic changes (confusion, agitation), and petechial rash (upper chest, axillae, conjunctivae). Occurs 24–72 hours after long bone fractures (especially femoral shaft). Diagnosis is clinical (Gurd's criteria). Treatment: supportive — O2, mechanical ventilation if needed. Prevention: early fracture fixation reduces incidence.

Venous Thromboembolism — Specific Trauma Considerations

The highest-risk trauma populations for VTE include: spinal cord injury (DVT rate 60–80% without prophylaxis), pelvic fractures, lower extremity fractures requiring immobilization, and prolonged ICU stays. Risk stratification tools (e.g., Greenfield Risk Assessment Profile for trauma) can guide prophylaxis intensity. Duplex screening ultrasound before mobilization is used at some trauma centers for high-risk patients. IVC filters are reserved for patients who cannot receive anticoagulation for >72 hours AND have a high risk profile — retrievable filters should be removed as soon as anticoagulation can be safely initiated. Complications of IVC filters include DVT below the filter, IVC thrombosis, filter migration, IVC perforation, and failure to retrieve.

Infection & Sepsis

Post-traumatic infections include surgical site infection (SSI), pneumonia (particularly ventilator-associated pneumonia — VAP), urinary tract infection (catheter-associated), bloodstream infections (central line-associated — CLABSI), empyema, intra-abdominal abscess, and wound/soft tissue infections (necrotizing fasciitis in contaminated wounds). Empiric antibiotics for post-traumatic intra-abdominal sepsis: piperacillin-tazobactam or carbapenem. Duration guidelines: hollow viscus perforation repaired within 24 hours requires only 24 hours of antibiotics (not prolonged courses). Damage control patients with open abdomens are at particular risk for fungal infections (Candida) — consider empiric antifungal therapy if multi-drug resistant bacteria or clinical deterioration despite antibiotics.

39 Abbreviations Master List