Responding to Emergencies

Commotio Cordis

Agitation of the heart

Cause: blow to chest resulting in VENTRICULAR FIBRILLATION

• blow must occur directly over the heart 10-30ms prio to T-wave

Percent of sudden cardiac death by commotio cordis

20%

Percent of survival by commotio cordis

15%

Care for commotio cordis

• Early CPR

• Early defibrillation AED

  • within 3-5 minutes is ideal

    • survival rate 41%-74%

  • EMS average response time form call to arrival is 6-8 minutes

percent wise how much does survival of a cardiac arrest decrease each minute

10%

when to assume cervical spine injury

• unconscious or altered consciousness

• bilateral neurological symptoms

• pain over spinal column with or without palpitation

• visual spinal deformity

Cervical spine injury response

1. stabilize and place cervical collar

2. may realign cervical spine

3. NO traction

4. airway exposed asap

may realign cervical spine UNLESS:

• movement increases or causes pain

• apprehension expressed by patient

• resistance is met - physical difficulty

• neurological symptoms

• muscle spasms

• airway compromised

cervical spine stabilization

rescuer at head is in charge

equipment removal

cervical collar placement

spine board applied

equpiment removal

• protective equipment may complicate or inhibit CPR

• remove BOTH helmet and shoulder pads

  • removal of facemask

Mechanical stresses

• load/stress

• deformation/strain

load/stress

external/internal force acting on tissue

deformation/strain

extent of deformation under loading

degree of deformation depends on:

• tissue composition

• speed of applied load

• frequency of loading

• direction of loading

stress-strain (load-deformation) curve

x-axis: strain

y-axis: stress

upward trend and then eventually levels out

includes:

• elastic region

• yield point

• plastic region

• ultimate point

elastic region

The initial portion of the stress-strain curve where a material will return to its original shape upon removal of the load. This region indicates elastic behavior of the material.

yield point

The point on a stress-strain curve where material begins to deform permanently. Beyond this point, the material will not return to its original shape once the load is removed.

plastic region

The portion of the stress-strain curve where the material undergoes permanent deformation. In this region, the material will not return to its original shape after the removal of the load.

ultimate point

The maximum stress that a material can withstand before failure occurs. Beyond this point, the material can either break or deform significantly.

tissue stresses

• tension

• bending

• compression

• torsion shear

• combined

tension

A type of stress that occurs when a material is pulled or stretched, resulting in a lengthening effect.

bending

The type of deformation that occurs when a force is applied to a material, causing it to curve or flex.

compression

A type of stress resulting from forces pressing together on a material, causing it to shorten or decrease in volume.

torsion

A type of stress that occurs when a material is twisted, leading to a shear deformation along its length.

shear

A type of stress that occurs when a material is subjected to two opposing forces, causing layers of the material to slide against one another.

combined

stresses that involve multiple forces acting simultaneously on a material, such as tension, compression, and torsion, resulting in complex deformation patterns.

mechanical properties of bone

• size

• shape

• direction of loading

bone size

increase mass = increase bone strength

• distribution of mechanical stresses

wolff’s law

bone shape

sudden shape changes are areas where mechanical stresses are concentrated

fracture healing

immobilizaiton for most cases

• casting/splinting/ORIF

• length of immobilization time depends on

  • vascularity of bone

  • stress on bone

• typically 6-8 weeks

healing process

• osteoblasts lay extra bone called callus

• need stimulus to regain compressive, tensile strength

• osteoclasts reshape bone

emergency action plan

• provides steps and guidance for what to do in an emergency

• should be reviewed at least once per year with all involved personnel

• helps to ensure that the best possible care is provided in an emergency

what do EAP include

• venue directions

  • venue map

• emergency personnel and their jobs, phone numbers

• emergency communication

• emergency equipment and location

• first responder roles