Blunt Trauma

Introduction to Blunt Trauma Kinetics of Blunt Trauma Types of Trauma Sections Introduction to Blunt Trauma Kinetics of Blunt Trauma Types of Trauma Blunt Trauma Explosion Other Blunt Trauma Examination, Diagnosis

Introduction to Blunt Trauma Most common cause of trauma death and disability Energy exchange between an object and the human body, without intrusion through the skin

Kinematics Process of examining the scene to determine potential injuries that result from the forces of motion Windshield, steering wheel, dashboard Was the patient flying thru the air? Roll-over? Engine block on lap? (intrusion)

Mechanism of injury MOI description of the mechanical and physiological changes that result in anatomical or functional damage of tissue Translation: What hit the patient???, what did the patient hit???!

Index of Suspicion Based on the MOI and kinetics Predict expected injuries Experience counts here! Be obsessive and compulsive, its OK!!

Kinetics of Blunt Trauma Inertia “A body in motion will remain in motion unless acted upon by an outside force.” “A body at rest will remain at rest unless acted upon by an outside force.” (Newton) Conservation of Energy “Energy can neither be created nor destroyed. It is only changed from one form to another.” (Newton)

Kinetics of Blunt Trauma Force (Newton’s 2nd law of motion) Emphasizes the importance of rate at which an object changes speed (acceleration or deceleration)

SOOOO The Force that puts an object in motion must be absorbed before the object will stop. Guess what absorbs that force???? This absorption is what causes tissue injury in the body.

Kinetics of Blunt Trauma Kinetic Energy Energy in Motion Double Weight = Double Energy Double Speed = Quadruple Energy SPEED IS THE GREATEST DETERMINANT

Physics (UGH!) Three types of forces in blunt trauma Compression Shear Overpressure

Compression Like laying an organ on a table and hitting it with a hammer, every time you hit it, cells are getting compressed and crushed. Enough said…..

Shear Occur when the organ and the organ’s attachment do not accelerate or decelerate at the same rate of speed, or two parts of an organ accelerate or decelerate at different rates. Examples are arch of aorta, spleen, kidney.

Overpressure Like hitting a closed paper bag with the open hand….the bag pops. Examples are like steering column hitting abdomen…pop! goes the diaphragm. Also can pop bladder, bowel, lungs……

Types of Trauma Blunt Closed injury Indirect injury to underlying structures Transmission of energy into the body Tearing of muscle, vessels and bone Rupture of solid organs Organ injury Ligamentum teres in the chest for example

Blunt Trauma: Car Crashes 44,000 people die each year on US highways Events of Impact Vehicle Collision Body Collision Organ Collision Secondary Collisions Objects inside vehicle strike occupant Additional Injuries Vehicle receives a second impact

Inertia and MVC’s

Protections (think Volvo!) Steel frame Belts Bags Seat construction Roof Crumple Zones

Blunt Trauma: Car Crashes Restraints Seatbelts Occupant slows with the vehicle Shoulder and Lap belts MUST be worn together Injuries if worn separately Airbags (SRS) Reduce blunt chest trauma Cause: Hand, Forearm, & Facial Injury Check for steering wheel deformity Side Airbags Child Safety Seats Infants and Small Children: Rear facing Older Child: Forward facing

Benefits of Air bags 700-1000 lives saved if all vehicles had head protecting SABs per year In side impacts where someone died, 60% suffered brain injury. Only 92 cases of SAB injury, 6 involving children, with no major injuries, only one minor injury (skin lac).

Bags and Belts Burns, abrasions Do not protect when a second collision hits! Abdominal injuries (seat too close) Chest injuries (short, elderly) Seat belt abrasions above the pelvis account for a 30-60% incidence of intra-abdominal injuries: intestinal rupture, mesenteric injury, vascular disruption

Blunt Trauma: Automobile Crashes Types of Impact Frontal: 32% Lateral: 15% Rotational: 38% Left & Right – Front & Rear Rear-end: 9% Rollover: 6%

Blunt Trauma: Car Crashes Frontal Impact Down-and-Under (legs lead point) Knee, femur, and hip fracture (dislocation of knee, fx acetabulum) Chest trauma-Steering Wheel Up-and-Over (head lead point) Head, c-spine injuries Tenses legs = Bilateral femur fracture Hollow organ rupture and liver laceration Similar chest trauma Axial Loading Ejection Due to up-and-over pathway Contact with the vehicle & external object

Blunt Trauma: Automobile Crashes Lateral Impact (intersection race) 15% of MVC’s but 22% of deaths Upper extremity injury Rib, clavicle, humerus, pelvis, femur fracture, c-spine dislocations, locked facets. Lateral compression Ruptured diaphragm, Spleen fracture, Aortic injury EVALUATE the unrestrained occupant

Blunt Trauma:Car Crashes Rotational Vehicle struck at oblique angle Less serious injuries unless strike a secondary object

Blunt Trauma:Car Crashes Rear-end Seat propels the occupant forward Head is forced backwards Stretching of neck muscles and ligaments Hyperextension & hyperflexion (think carotid) Rollover Multiple points of impact Ejection or partial ejection (think: arm out of window, then roll….) Less injury with restraints

Blunt Trauma: Automobile Crashes Vehicle Crash Analysis Crumple Zones Intrusion (one inch for each mile per hour) Deformity of Vehicle Use of Restraints Intoxication Fatal Accidents: >50% involved ETOH Recreational Accidents

Blunt Trauma: Automobile Crashes Vehicular Mortality Head: 48% Internal (Torso): 37% Spinal & Chest fracture: 8% Extremity fracture: 2% All Other: 5%

Blunt Trauma: Automobile Crashes Crash Evaluation Collision Questions How did collision occur? Direction? Speed? Similar/Different sized? Secondary collisions? Cause of Crash Weather & visibility? Alcohol involved? Skid marks? Auto Interior Starring of windshield? Steering wheel deformity? Dash deformity? Intrusion?

The “Lucky Other Guy” The passenger in the same car as the deceased driver for example. BUT, this “lucky”person was in the same vehicle and the energy exchange on the body was the same. So you’d better find that unrecognized injury!

Blunt Trauma: Motorcycle Crashes Serious injuries can occur with high and low speed collision. Types of Impact Frontal Angular Sliding (“laying the bike down”) Ejection Initial Bike/Object Collision Rider/Object Rider/Ground

Motorcycle Injuries No helmet use increases chance of head injury by 300%. Does not protect c-spine, but does not injure it either. Anti-helmet organizations such as American Motorcycle Association may say different………

Blunt Trauma:Pedestrian Struck Adults Adults turn away and run (lat,post injuries) Bumper strikes lower legs first Victim rolls up and over and thrown Children Children turn toward (ant injuries) Femurs, Pelvis often injured Thrown away or run over

Blunt Trauma: Recreational Vehicle Accidents Lack structure and restraint system Types of Vehicles Snowmobiles Personal watercraft ATV’s

Other Types of Blunt Trauma Falls Stairs, Force, Surface Landing Area Surface Type Body Part Height of Fall (3 times height of victim) Elderly Axial Loading…..

Maam, you aren’t on Coumadin, are you??????

Other Types of Blunt Trauma Crush Injuries Cause Structural collapse, explosion, industrial; or agricultural Great force to soft tissue and bones Tissue stretching and compression Extended pressure results in anaerobic metabolism distal to compression Return of blood flow, toxins to entire body Severe hemorrhage due to severe damaged blood vessels Care Prolonged crush Medications Sodium Bicarbonate: Reduce Acidosis Morphine: Pain management

Blunt Trauma: Blast Injuries Dust, Fumes, Explosive Compounds Explosion Fuel + Oxidant combine instantaneously Heat & Pressure Wave

Primary Injuries rapid changes in atmospheric pressure from movement of blast wave hollow organs more susceptible blast wave rapidly passes through tissue of varying density; if lower density is adjacent to higher density surface tissue of denser tissue is disrupted- “spalling” as wave transverses the walls of the alveoli (high density), they rupture as the wave encounters the air within the alveoli (low density); massive destruction of alveoli and diffuse hemorrhage in lung

Implosion pressure wave passes through the lung, it forces blood out of the vascular space and into the alveoli wave of high pressure is followed by wave of low pressure allowing alveoli to expand rapidly with further tearing of the lung parenchyma, atelectasis, hemorrhage

Secondary Injury Results from flying debris created by the explosion and carried by blast winds injuries are typically severe and penetrating due to high KE of projectiles

Tertiary Injuries Blast winds are sufficient force to cause victims to become human missiles victim strikes the ground

Associated Injuries Injuries resulting from changes in the environment as a consequence of the explosion fire; burns combustion of toxic products; poisoning leaks of toxic chemicals; asphyxiation

Explosion Pressure Wave Burns Projectiles Personnel Displacement Structural Collapse Blast Wind Burns Projectiles Personnel Displacement Blast Injury Phases Primary: Heat of the explosion Secondary: Trauma caused by projectiles Tertiary: Personnel displacement and structural collapse

Explosion Blast Injury Assessment Be alert for secondary device Initial scene size-up important Establish Incident Command System (ICS) Evaluate for secondary hazards Injury Patterns Rupture of Air or Fluid Filled Organs Lung: Late manifestation (heat & pressure) Hearing loss

Explosion Blast Injury Care Lungs Abdomen Forceful compression and distortion of chest cavity Compression and decompression Pulmonary Embolism, Dyspnea, Hemoptysis, Pneumothorax Abdomen Compression & Decompression Release of bowel contents Diaphragm rupture from pushing of organs up into thorax area

Explosion Blast Injury Care Ears Penetrating Wounds Burns Initial Hearing Loss Injury improves over time Penetrating Wounds Care as any serious open wound or impaled object Burns Treatment consistent with traditional management.