Quantum Physics and the TimeSpace Continuum An in depth and highly detailed analysis of the physical universe and it’s relevance to the pre-hospital emergency medical practicum. TRAUMA KINEMATICS An Introduction to the Physics of Trauma Trauma Statistics • Over 150,000 trauma deaths/year – Over 40, 000 are auto related • Leading cause of death for ages 1-40 • One-third are preventable • Cost exceeds $220 billion (2001) • Unnecessary deaths are often caused by injuries missed because of low index of suspicion Kinematics • Physics of Trauma • Understanding kinematics allows prediction of injuries based on forces and motion involved in an injury event. Basic Principles • Conservation of Energy Law • Newton’s First Law of Motion • Newton’s Second Law of Motion • Kinetic Energy Newton’s First Law • Body in motion stays in motion unless acted on by outside force • Body at rest stays at rest unless acted on by outside force Newton’s Second Law • Force of an object = mass (weight) x acceleration or deceleration (change in velocity) • Major factor is velocity • “Speed Kills” Law of Conservation of Energy • For every action there is an opposite and equal reaction • Energy cannot be created or destroyed • Energy can only change from one form to another Kinetic Energy • Energy of Motion • Kinetic energy = ½ mass of an object X (velocity)2 • Injury doubles when weight doubles but quadruples when velocity doubles So… When a moving body is acted on by an outside force and changes its motion, then kinetic energy must change to some other form of energy. If the moving body is a human being and the energy transfer occurs too rapidly, then trauma results. Blunt Force Trauma • Force without penetration • “Unseen injuries” • Cavitation towards or away from the injury Penetrating Trauma • Piercing or penetration of body with damage to soft tissues and organs • Depth of injury Mechanism of Injury Profiles Motor Vehicle Collisions • Five major types of motor vehicle collisions: – Head-on – Rear-end – Lateral – Rotational – Roll-over Motor Vehicle Collisions • In each collision, three impacts occur: – Vehicle – Occupants – Occupant organs Head-On Collision Head-on Collision • Vehicle stops • Occupants continue forward • Two pathways – Down and under – Up and over Frontal Collision • Down and under pathway – Knees impact dash, causing knee dislocation/patella fracture – Force fractures femur, hip, posterior rim of acetabulum (hip socket) – Pelvic injuries kill! Frontal Collision • Down and under pathway – Upper body hits steering wheel • Broken ribs • Flail chest • Pulmonary/myocardial contusion • Ruptured liver/spleen Frontal Collision • Down and under pathway – Paper bag pneumothorax – Aortic tear from deceleration – Head thrown forward • C-spine injury • Tracheal injury Frontal Collision • Up and over pathway – Chest/abdomen hit steering wheel • Rib fractures/flail chest • Cardiac/pulmonary contusions/aortic tears • Abdominal organ rupture • Diaphragm rupture • Liver/mesenteric lacerations Frontal Collision • Up and over pathway – Head impacts windshield • Scalp lacerations • Skull fractures • Cerebral contusions/hemorrhages – C-spine fracture Rear-end Collision Rear-end Collision • Car (and everything touching it) moves forward • Body moves, head does not, causing whiplash • Vehicle may strike other object causing frontal impact • Worst patients in vehicles with two impacts Lateral Collision Lateral Collision • Car appears to move from under patient • Patient moves toward point of impact • Increased potential for “shearing” injuries • Increased cervical spine injury Lateral Collision • Chest hits door – Lateral rib fractures – Lateral flail chest – Pulmonary contusion – Abdominal solid organ rupture • Suspect upper extremity fractures and dislocations Lateral Collision • Hip hits door – Head of femur driven through acetabulum – Pelvic fractures • C-spine injury • Head injury Rotational Collision Rotational Collision • Off-center impact • Car rotates around impact point • Patients thrown toward impact point • Injuries combination of head-on, lateral • Point of greatest damage = point of greatest deceleration = worst patients Rollover Roll-Over • Multiple impacts each time vehicle rolls • Injuries unpredictable • Assume presence of severe injury • Justification for Transport to Level I or II Trauma Center Restrained vs Unrestrained Patients • Ejection causes 27% of motor vehicle collision deaths • 1 in 13 suffers a spinal injury • Probability of death increases six-fold Restrained with Improper Positioning • Seatbelts Above Iliac Crest – Compression injuries to abdominal organs – T12 - L2 compression fractures • Seatbelts Too Low – Hip dislocations Restrained with Improper Positioning • Seatbelts Alone – Head, C-Spine, Maxillofacial injuries • Shoulder Straps Alone – Neck injuries – Decapitation Motorcycle Collisions • Rider impacts motorcycle parts • Rider ejected over motorcycle or trapped between motorcycle and vehicle • No protection from effects of deceleration • Limited protection from gear Pedestrian vs. Vehicle • Child – Faces oncoming vehicle – Waddell’s Triad • Bumper • Hood • Ground Femur fracture Chest injuries Head injuries Pedestrian vs. Vehicle • Adult – Turns from oncoming vehicle – O’Donohue’s Triad • Bumper • Hood Tib-fib fracture Knee injuries Femur/pelvic Falls • Critical Factor – Height • Increased height + Increased injury – Surface • Type of impact surface increases injury – Objects struck during fall – Body part of first impact • Feet • Head Buttocks • Parallel Falls • Assess body part that impacts first, usually sustains the bulk of injury • Think about the path of energy through body and what other organs/systems could be impacted (index of suspicion) Falls onto Head/Spine • Injuries may not be obvious • C-spine precautions! • Watch for delayed head injury S/S Falls onto Hands • Bilateral colles fractures • Potential for radial/ulna fractures and dislocations Fall onto Buttocks • Pelvic fracture • Coccygeal (tail bone) fracture • Lumbar compression fracture Fall onto Feet* • Don Juan Syndrome – Bilateral heel fractures – Compression fractures of vertebrae – Bilateral Colles’ fractures Index of Suspicion Stab Wounds • Damage confined to wound track – Four-inch object can produce nine-inch track • Gender of attacker – Males stab up; Females stab down • Evaluate for multiple wounds – Check back, flanks, buttocks Stab Wounds • Chest/abdomen overlap – Chest below 4th ICS = Abdomen until proven otherwise – Abdomen above iliac crests = Chest until proven otherwise Stabbings • Always maintain high degree of suspicion with stab wounds • Remember: small stab wounds do NOT mean small damage Gunshot Wounds • Damage CANNOT be determined by location of entrance/exit wounds – Missiles tumble – Secondary missiles from bone impacts – Remote damage from • Blast effect • Cavitation Gunshot Wounds • Severity cannot be evaluated in the field or Emergency Department • Severity can only be evaluated in OR Significant ALS MOI • Multi-system trauma • Fractures in more than one location • MVA – death in same vehicle, high speed or significant vehicle damage • Falls > 2 X body height • Thrown > 10 – 15 feet • Penetrating trauma to the “box” • Age co-factors: < 6 or > 60 • “Lucky Victim” Conclusion • Think about mechanisms of injury • Always maintain an increased index of suspicion • Doing YOUR job as an EMT will lead to: – Fewer missed injuries – Increased patient survival