Kinematics of Trauma

Question 1

What is kinematics?

Answer 1

• It describes the motion of objects without consideration of how that motion occurred.

Question 2

How does kinematics describe motion?

Answer 2

• Type of motion
• Location of motion
• Magnitude of motion
• Direction of motion

Question 3

What does understand the kinematics of a car crash or fall allow us as paramedics to understand or grasp an understanding or idea of?

Answer 3

• Enables prediction of injury patterns.

Question 4

What is Velocity?

Answer 4

• The rate of change of positions. You require the speed and direction of the object to figure out your Velocity.

Question 5

What are the 4 Physical laws that are relevant in trauma?

Answer 5

• Newton’s First Law
  o An object, either at rest or in motion, will remain in that state until acted upon.
• Conservation of Energy
  o Energy cannot be created or destroyed, only the state can be changed
• Newton’s Second Law of Motion
  o Net Force (F) = mass (M) x acceleration (a)
• Kinetic Energy
  o KE = half the mass (1/2 M) x velocity Squared (v2)

Question 6

What do these laws of physics mean to a paramedic?

Answer 6

• A paramedic should be aware of them for trauma jobs as you consider the forces involved, what a larger car traveling at higher speed does to a patient, compared to a smaller or lighter car traveling at lower speeds.

Question 7

What three types of impacts occur doing an MVA were energy is transferred?

Answer 7

• Vehicle collides with object
• Occupant collides with the inside of the vehicle
• Organs collide with the inside of the occupants

Question 8

What forces are associated with the above triad?

Answer 8

• Blunt and shearing forces applied to the body during rapid deceleration.

Question 9

What factors alter the type of injury a patient may suffer in an MVA.

Answer 9

• The type of collision
• The position of the occupant and types of objects that they are likely to strike
• The application of vehicle fitted restraints or the deployment of air bags

Question 10

What are the 5 groups of mechanism in an MVA?

Answer 10

• Head on (frontal) Impact
• Later impact
• Rear end impact
• Rotational impact
• Rollover

Question 11

In what direction can an unrestrained passenger travel in car in relation to the dashboard?

Answer 11

• Down and under it (knees are the leading part of the body)

- Up and over (Ribs and thorax are leading part of the body)

Question 12

What are potential injuries from down and under type forces?

Answer 12

• Femoral and hip fractures and associated haemorrhages

- Knee and lower leg fractures and associated haemorrhage

Question 13

What are potential injuries from up and over type forces?

Answer 13

• Rib fracture and hemopneumothorax
• Pulmonary or cardiac contusion
• Abdominal organ and major vessel rupture and laceration
• Traumatic head and spinal injuries

Question 14

When does lateral impact occur?

Answer 14

• When a vehicle is hit on its side, also referred to as a T-bone.

Question 15

What are some considerations when attending a lateral impact?

Answer 15

• Has the vehicle remained in place after initial impact?
• How many passengers are in the car?
• How much intrusion has occurred into the cabin?
• Has ejection occurred? Either through empty baby seats or other passengers?

Question 16

What are possible patterns of injury included in a later impact?

Answer 16

• Compression of pelvis, abdomen and torso
• Rib fracture and pulmonary contusion
• Organ rupture. In particular spleen/liver
• Pelvic fracture
• Head and neck injuries

Question 17

Does a standard seatbelt provide restraint in the case of a lateral impact?

Answer 17

• No

Question 18

What occurs when a vehicle is struck from behind?

Answer 18

• Rapid acceleration occurs

Question 19

What are possible injuries of a rear impact?

Answer 19

• Spinal injuries especially hypertension of the C- Spine.

Question 20

What type of injuries occur in a rotational Impact?

Answer 20

• Occupants suffer injuries that are common in frontal and lateral impacts.

Question 21

What injuries may be sustained in a roll over impact?

Answer 21

• Occupants are thrown around within the vehicle.

- People may sustain multiple system injures associated with all mechanism of MVA.

Question 22

What else may occur during a roll over incident?

Answer 22

• Other objects within the car may turn in to projectiles and occupants may also be ejected allowing further injuries to be sustained.

Question 23

What are common types of Deceleration and compression injuries?

Answer 23

• Head injuries

- Thoracic injuries and abdominal

Question 24

What are the forces involved in the deceleration injuries?

Answer 24

• Shearing forces that may leave the PT presenting perfectly unharmed but the forces have caused a significant organ to fail or become detached or rupture.

Question 25

What is the likely hood of death for those patients ejected from vehicles?>

Answer 25

• 6 times the risk of death.

Question 26

What types of impacts can a seatbelt provide protection from?

Answer 26

• Forward and rear. However, they are not always able to prevent injuries.

Question 27

What do airbags do?

Answer 27

• They absorb energy slowly, they also deploy and deflate within 0.5 seconds.

Question 28

In what types of crashes are frontal airbags of little to no use?

Answer 28

• Lateral and rollover collisions

Question 29

What potential injuries are airbags likely to cause?

Answer 29

• Abrasions, foreign bodies to face/eyes or allergic/respiratory reactions and burns.

Question 30

What is the cause of whiplash?

Answer 30

• The head extending backward from the torso in the initial stage of rear impact the being thrown forward.