Kinematics of Trauma

Question 1

Physics

Answer 1

• KE = 1/2 mv^2
• velocity has greatest impact
  newtons first law/inertia - objects in motion will stay in motion
• pressure = force/area

Question 2

Stopping Suddenly

Answer 2

• in MVAs, a large eternal force stop the car on impact

Question 3

Collision Sequence

Answer 3

1. vehicle hits tree
2. body hits steering wheel, causing broken ribs
3. ” causing myocardial infarction

Question 4

Deceleration

Answer 4

= the true villain

• rapid deceleration = large force over short period (BAD)
• slow deceleration = large force over long period (NOT AS BAD)

Question 5

Car Safety

Answer 5

features: rear and front crumple zones, airbags, rear and front seat belts, side impact bars, collapsible steering wheel

Question 6

Types of MVAs

Answer 6

• frontal
• rear
• lateral
• rotational
• roll over

Question 7

Frontal and Rear

Answer 7

• worry about spinal/brain injury

- worry about spinal flexion (decreases angle between bones) and spinal extension (increases angle between bones)

Question 8

Lateral and Rotational

Answer 8

= a car collision on sides of vehicle; lacks cushioning on sides

• lateral injuries to neck and clavicle are common
• passengers can be hit directly
• prone to rollovers

Question 9

Rollovers

Answer 9

• caused by lateral or rotational collisions
• most serious collision: passengers prone to multiple injuries, multiple points of impact, rotation can exacerbate previous injuries and create new ones
• wear seatbelts!

Question 10

Vehicle-Pedestrian MVAs

Answer 10

• barriers from collisions; pedestrians lack proper protection
• kids are more prone to fatal injuries because of height

Question 11

Coup and Contrecoup

Answer 11

= injuries associated with cerebral contusion (brushing of brain)

• coup = injury occurs on side of impact
• contrecoup = injury occurs on opposite of impact

Question 12

MVA Consideration

Answer 12

1. scene safety - leaking gas, power lines, environmental factors; turn off car
2. assessments: how fast was vehicle going? what angle was car hit from? seat belts? air bags? crumpled front or back? did car flip? which side got hit ? additional resources?

Question 13

Penetrating Trauma

Answer 13

• injury that pierces the skin; large force over small area
• ex) bullets, arrows, knives
• injuries could be fatal
• area of injury: potential organ damage? depth? is it still there? entry and exit wounds?

Question 14

Entry and Exit Wounds

Answer 14

• entry wounds = usually round and small (relative to exit wound)
• always check for exit wounds
• assessment: what was angle and speed of object? cavitation? fragmentation?
• only remove object if it impedes airway, transport, or CPR

Question 15

Blunt Trauma

Answer 15

• injury caused by dull object; does not typically break the skin; can be life threatening
• large force over large area
• ex) bats, balls, fists, feet
• assessment: consider area of injury and organs, angle of impact, broken bones, weapon, internal bleeding

Question 16

Forces

Answer 16

• • shearing/torsion = when two forces push in opposite direction
• • compression = injuries where same mass is forced into smaller volume
• • tension = injuries where same mass is forced into larger volume

Question 17

Falls

Answer 17

• can lead to serious injuries
• serious falls = >3 feet/5 steps OR patients height
• children, elderly, & pregnant women are more at risk

Question 18

Blast Injuries

Answer 18

5 Phases:

1. primary = blast wave
2. secondary = injuries due to launching of fragment, debris, and people
3. tertiary = injuries due to collisions of F, D, and P
4. quaternary = heat injuries
5. quinary = injuries due to radiation and biological causes

Question 19

Lifting

Answer 19

• lift with legs, not back
• stand close to object with feet shoulders width apart
• keep back straight, tighten core
• ask for help