10 Burn, Electrocution, Lightning

Question 1

Categories of burn

Answer 1

flame, contact, radiant heat, scalding, chemical, microwave

Question 2

Burn categories

Answer 2

• flame burns: actual contact of body and flame, skin progress to charring
• flash burns: initial ignition from flash fires that result from sudden ignition/explosion of gases, petrochemical, fine particulate material. Short duration ( a few secs), burned uniformly, usually result in partial thickness burns with singed hair
• contact “: physical contact between body and hot object. If expose to surface temp > 70 deg, trans epidermal necrosis occurs in less than a sec
• Radiant heat: caused by heat waves. No contact between body and flame or hot surface. Skin erythematous blistered > light brown, leathery > initially hair is intact > if radiant heat cont, charring of body
• scalding: contact w/ hot liquid most commonly water. Occur on exposed skin

Question 3

Severity of burns depend on

Answer 3

• extent of burned area, victims age, presence of inhalation injuries

Question 4

What is ‘rules of nines’

Answer 4

• burns covering > 15% of TBSA in adults, > 10% in children warrant fluid resuscitation
• a large area involved may be more dangerous to life than a deeper, more localised burn

Question 5

Severity of burns

Answer 5

• first degree (superficial) burns: erythematous skin w/o blisters, dilated congested vessels in dermis. epidermis intact but has some injuries to cells. Subsequent desquamation of necrotic epidermal cells (peeling in sunburns). Can be caused by prolonged exposure to low intensity heat or light (sunburn) or short duration exposure to high intensity heat or light
• second degree (partial thickness) burns: external appearance moist, red, blistered lesion
  Superficial: destruction of stratum granulosum and corneum w/ basal layer not totally destroyed and edema at dermal-epidermal junction. This injury heals w/o scarring
  Deep: complete destruction of epidermis and destruction of most basal layer. Might be blistering. Dermal appendages (hair and sweat gland) r spared. Second degree burns heal w/o scarring

Third degree (full thickness) burns
- coagulation necrosis of epidermis and dermis w/ destruction of dermal appendages. Externally, lesion dry white leathery appearance, no blisters. This wound heals as a scar

Fourth degree burns: incinerating injuries extending deeper than the skin

Question 6

Types of death caused by fire

Answer 6

• immediate death: either direct thermal injury to body (burns) or Phenomenon called ‘smoke inhalation’
• delayed death: within first 2 or 3 days caused by shock, fluid loss, acute respiratory failure caused by inhalation of gases. Death after this period caused by sepsis or chronic respiratory insufficiency

Question 7

Common PM artefact

Answer 7

• post mortem epidural hematoma: choc brown colour, crumbly or honeycomb appearance, large, fairly thick, overlie frontal, parietal, temporal
• skin splits: seen over extensor surfaces and joints, head. The skin split show no bleeding in deeper tissues

Question 8

Fatal CO level

Answer 8

• if CO sole cause of death, blood saturation atleast 40% is required
• carbon monoxide valuable indicator to see victim alive after the fire began
• presence of more than a smoker’s level of 5 percent saturation of blood with HbCo means breathing occured after the fire began
• if body not have HbCo does not mean victim died before fire began (rapid fire, flash fire by petrol takda hbco in blood)