ByBy

Lecturer of Forensic Medicine & Clinical ToxicologyLecturer of Forensic Medicine & Clinical Toxicology

DefinitionDefinition

A thermal injuryA thermal injury is a tissue injury resulting is a tissue injury resulting from the application of heat in any form tofrom the application of heat in any form tothe external or internal surface of the body.the external or internal surface of the body.

Types of Types of thermalthermal injuriesinjuries

Dry or simple burn.Dry or simple burn.

Scald or moist burn.Scald or moist burn.

Chemical or corrosive burn.Chemical or corrosive burn.

Electric burn.Electric burn.

Radiation burn.Radiation burn.

Old classificationOld classificationFirst degree burnFirst degree burn

Second degree burnSecond degree burn

Third degree burnThird degree burn

Fourth degree burnFourth degree burn

Fifth degree burnFifth degree burn

Sixth degree burnSixth degree burn

Recent classificationRecent classification

Epidermal degreeEpidermal degree 11stst & 2 & 2ndnd degree degree

Dermo - epidermal burnDermo - epidermal burn33rdrd & 4 & 4thth degree degree

Deep burnDeep burn55thth & 6 & 6thth degree degree

Dry burnDry burn ScaldScald CorrosiveCorrosive

CauseCause

ClothesClothes

CharringCharring

Flame or Flame or heated heated

bodybody

Steam or Steam or hot hot

liquidliquid

Corrosive Corrosive acid or acid or alkalialkaliBurBur

ntntWWetet

EateEatenn

PresePresentnt

AbsAbsentent

With With mineral mineral

acidacid

SkinSkin Dry & Dry & charredcharred

Sodden & Sodden & bleachedbleached

Stained & corrodedStained & corroded

ScarScar Thick with Thick with disfigurementdisfigurement

Less Less disfiguredisfigure

mentment

Much Much disfiguremdisfigurem

entent

Air passageAir passage Contains Contains sootsoot

No No sootsoot

No No sootsoot

BloodBlood Thick, Thick, viscid & viscid & contains contains

COHbCOHb

DegreeDegree Any Any degreedegree

11stst, 2, 2ndnd & 3& 3rdrd

11stst, 3, 3rdrd, , 44thth

HairHair SingSingeded

WetWet EateEatenn

VesiclesVesicles At At circumferenccircumferenc

e of burnt e of burnt areaarea

Over burnt Over burnt areaarea

Rarely Rarely foundfound

Site & spreadSite & spread From From below below

upwardupward

From From above above

downwardownwardd

At & below At & below site of site of contactcontact

Factors affecting degree of burnFactors affecting degree of burnA) Extent of burnt area:A) Extent of burnt area: is determined by rule of nine of Wallace.is determined by rule of nine of Wallace.

B) Depth of burn:B) Depth of burn: The 3rd degree burn is the most serious one.The 3rd degree burn is the most serious one.

C) Site of burn.C) Site of burn. Neck, abdominal wall or genitalia are more Neck, abdominal wall or genitalia are more dangerous than those of the extremities.dangerous than those of the extremities.

D) AgeD) Age

E) SexE) Sex

F) General health.F) General health.

Causes of death from burnCauses of death from burnIIII) ) Rapid death Rapid death ""within 6-48 within 6-48

hourshours:”:”I)I) Immediate causes Immediate causes ""within 6 hourswithin 6 hours““

Neurogenic shock.Neurogenic shock.

Associated accidental serious injuries to Associated accidental serious injuries to vital organs.vital organs.

Asphyxia (suffocation). Asphyxia (suffocation).

Traumatic asphyxia.Traumatic asphyxia.

Secondary oligaemic shock.Secondary oligaemic shock.

Secondary toxaemic shock.Secondary toxaemic shock.

Acute oedema of glottis (in the neck).Acute oedema of glottis (in the neck).

Pulmonary fat embolism (burn in a fatty areaPulmonary fat embolism (burn in a fatty area.(.(

IIIIII) ) Death within 2-7 daysDeath within 2-7 days::- Supra-renal haemorrhage.Supra-renal haemorrhage.

- Bronchopneumonia.Bronchopneumonia.

- Inflammation of serous membranes.Inflammation of serous membranes.

- Septicemia.Septicemia.

- Tetanus, gangrene and erysipelas.- Tetanus, gangrene and erysipelas.:

IV) Death after one week:IV) Death after one week:

- Rupture of an acute duodenal ulcer - Rupture of an acute duodenal ulcer ((at at 12th day12th day)) ((curling's ulcercurling's ulcer) () (stress ulcerstress ulcer)):: may be due to hypovolaemia causing may be due to hypovolaemia causing devitalization of mucous membrane in devitalization of mucous membrane in addition to the absorbed burn toxins which addition to the absorbed burn toxins which are excreted by the liver into the are excreted by the liver into the duodenumduodenum..

--Liver, kidney or heart damageLiver, kidney or heart damage: : cell cell degeneration and necrosis of these organs degeneration and necrosis of these organs due to the effect of burn toxins due to the effect of burn toxins metabolismmetabolism..

Burn vitalityBurn vitality

Line of hyperemiaLine of hyperemia PresentPresent AbsentAbsent

Antemortem burnAntemortem burn Postmortem burnPostmortem burn

absent poor inabsent poor in albumin and chloridealbumin and chloride

Albuminous fluidAlbuminous fluid rich in chloriderich in chloride

Infl., pusInfl., pushealinghealing

PresentPresent AbsentAbsent

NilNil

VesiclesVesicles

Vital reactionVital reaction

SootSoot in URTin URT

Presence of COHbPresence of COHb

Cause of deathCause of death

PresentPresent AbsentAbsent

NothingNothingBut burnBut burn Other causesOther causes

Age of BurnAge of Burn

ErythemaErythema 3636 hshs 4848 hshsAppearsAppears

immediatelyimmediately

VesiclesVesicles 11 ww 22 wswsAppearsAppears 2-3hs2-3hs

SepsisSepsis 3636 hshs 22 – – 33daysdays

Superficial sloughSuperficial slough 11 ww

Deep sloughDeep slough 33 wsws

ScarScar 22 mm 66 mmRedRed CopperyCoppery

Complications of BurnComplications of Burn

SepsisSepsis KeloidKeloid formationformationDeformitiesDeformities

Postmortem Picture of BurnPostmortem Picture of Burn -- The body shows evidence ofThe body shows evidence of antemortem antemortem burnsburns of various degrees. of various degrees. - The body presents a peculiar attitude;The body presents a peculiar attitude; attitude of defenceattitude of defence,, boxingboxing or or "Pugilistic "Pugilistic attitude". attitude".

- Crimson red colour of hypostasis.Crimson red colour of hypostasis.

- Generalized visceral congestion and HgeGeneralized visceral congestion and Hge in the internal organs.in the internal organs.

-- Particles of soot are present in the air Particles of soot are present in the air passage. passage.

- Subcutaneous or subserous peticheal hgeSubcutaneous or subserous peticheal hge may be presentmay be present ..

- Haemoconcentration of blood due to lossHaemoconcentration of blood due to lossof plasma and cherry red colour of the skin.of plasma and cherry red colour of the skin.

- - -Skull may show thermal fracture "fissureSkull may show thermal fracture "fissure - fracturefracture.“.“

Points of differentiation () thermal & traumatic fracturePoints of differentiation () thermal & traumatic fracture

ThermalThermal FractureFracture Traumatic FractureTraumatic Fracture

The The brain is shrunkenbrain is shrunken The The brain is edematousbrain is edematous

Extradural haematomaExtradural haematoma doesn’tdoesn’t fill the spacefill the space

Extradural haematomaExtradural haematoma fill the spacefill the space

The fracture is not displacedThe fracture is not displaced The fracture is displacedThe fracture is displacedPostmortem signs of burnPostmortem signs of burnOther postmortemOther postmortem signs of death signs of death & &associated with contused wound in scalpassociated with contused wound in scalp

Electric burnElectric burnFactors influencing the effect of electric currentFactors influencing the effect of electric current

PhysicalPhysical PhysiologicalPhysiological

VoltageVoltage

Nature of currentNature of current

Duration of Duration of contactcontact

Resistance of Resistance of body tissuebody tissue

HumidityHumidity

Pathway of Pathway of currentcurrent

Anticipation of Anticipation of shockshock

General healthGeneral health

Causes of DeathCauses of DeathVentricularVentricular fibrillation fibrillation

Respiratory failureRespiratory failureCentralCentral

PeripheralPeripheral

Cerebral anoxiaCerebral anoxia

Hyperthermic effectHyperthermic effect

Cardiac arrestCardiac arrest

Electric burnElectric burn

P.M. Picture of Electric BurnP.M. Picture of Electric Burn

Rapid onset of rigor mortisRapid onset of rigor mortis

Marked hypostasisMarked hypostasis

Presence of current markPresence of current mark

Internal signs of asphyxiaInternal signs of asphyxia

Current MarksCurrent MarksN / E appearanceN / E appearanceMicroscopic appearanceMicroscopic appearance

- Compression of the stratum corni which Compression of the stratum corni which stains deeply with superficial carbonization.stains deeply with superficial carbonization.

- Separation of the cells in the form of slitsSeparation of the cells in the form of slits (electric channels).(electric channels).

- Elongation of both cells and nuclei.- Elongation of both cells and nuclei.

- It is of the same size and shape as theIt is of the same size and shape as the conductor.conductor.

- Grayish-white painless areas of aseptic Grayish-white painless areas of aseptic necrosis.necrosis.

-- They vary from superficial circumscribedThey vary from superficial circumscribed lesions to severe burns with full thickness lesions to severe burns with full thickness tissue necrosis.tissue necrosis.

DefinitionDefinition

It is the discharge of the atmosphere It is the discharge of the atmosphere potential ()potential () clouds,clouds, or ()or () clouds and clouds and Earth. Earth.

-The electric current is DC not AC.The electric current is DC not AC. -About 20.000 amperes. About 20.000 amperes.

-About 100 - 1000 million volts.About 100 - 1000 million volts.

- A single flash lasts 1/1000th of a second. - A single flash lasts 1/1000th of a second.

Lightning syndromeLightning syndrome

Characterized by:Characterized by: Loss of consciousness.Loss of consciousness.

Skin burn (similar to 1Skin burn (similar to 1stst degree burn. degree burn.

Conductive deafness.Conductive deafness.