Burn Injuries – Forensic approach -Tom Bennett 1 1 2 2 1 Burns: objectives • To understand the multiple sources of energy to produce tissue burn injuries. • To recognize the tissue reactions and appearances characteristic of each type of injurious agent. • To differentiate amongst accidental and non-accidental burn injury patterns. 3 3 Treat a fire fatality scene like a crime scene • Remember what you do or touch or move • Document what you do or touch or move • Secure and seal off the scene 4 4 2 At a crime scene, put your hands in your pockets! •Play with yourself, not the crime scene •Everyone will be happier 5 5 Once the fire victim is found: • If there is any question as to whether a fire victim is deceased, initiate CPR. • If death pronounced, DO NOT allow the body to be moved (unless it at risk of further damage) until Coroner authorizes it. 6 6 3 The six basic questions we must answer for any death (e.g., fire): • Who - Identification of body • What - Determining CAUSE of fire / injuries • When - Time of death relative to time of fire (i.e., are burn injuries premortem?) • Where - Determine where injuries were received, and how positioning of body relates • Why - Can autopsy help identify cause of fire • How - Determine MANNER of death 7 7 ALL burn deaths are Coroner / Medical Examiner cases • An autopsy is needed in essentially all cases 8 8 4 What tools do we have? • Autopsy • Toxicology • X-rays • Crime lab … • Scene investigators • History • etc. 9 9 Autopsy of a burned body: • Gather ALL of the body - may be in pieces • Photography & Diagrams • X-rays • Remnants of clothing, possessions & debris - identify & save • Complete external & internal examination • Toxicology - get blood (liquid), urine, vitreous fluid, muscle, etc. -(any available) – obtain [Alcohol] and [Carbon Monoxide] on all cases 10 10 5 Gather all the pieces • 1 or 2 (or more) people? • Co-mingled remains 11 11 48wm found in bed, in motel room: - where fire started? -lividity & color? - type of fire? - BAC & [CO]? 12 12 6 13 13 14 14 7 Photography / Diagrams • “A picture is worth 1000 words” • Digital v. 35mm v. Video -(Why not all three?) • Diagrams can be added to your reports, to include measurements, observations, etc. 15 15 Toxicology • Even in severely burned bodies, it is often possible to obtain blood from the heart or great vessels. • Obtain blood in both grey-top and plain containers. • We need (at least) [EtOH] & [CO]. 16 16 8 Toxicology - other fluids 17 17 X-rays • Artifact v. significant findings • Which films to get? – Skull AP & lateral – Chest AP – Abdomen – others? 18 18 9 Artifacts seen in X-rays 19 19 20 20 10 SCENE is usually more valuable than BODY, but the autopsy may help direct the investigation of the scene • Autopsy findings (e.g., homicide) may redirect the search for cause or origin. • Odor of accelerant may be found in lungs or GI gas. • Bomb fragments or other foreign material. 21 21 The six basic •Who? questions: •What •When •Where •Why •How 22 22 11 Who? • Even in mild burns, physical features are altered, and visual identification may be unreliable. • Rely upon: – dental – fingerprint – x-ray – DNA, etc. 23 23 Dental identification 24 24 12 Fingerprints • Fingerprints may be obtained, even in some severely-burned cases – Pugilistic pose – Skin slippage (stocking-glove) – Dermal prints 25 25 Children? • These two girls (ages 4 & 5), found together in a bed in a fire starting in the bedroom where they were to be taking a nap. • Rare to find dental records, fingerprints, x- rays, etc. • DNA is expensive. • What to do to achieve reliable ID? 26 26 13 eruption of teeth? hair color ?-clothes 27 27 The six basic •Who questions: •What? •When •Where •Why •How 28 28 14 What? -Cause of death: -Trauma -Heat -Lack of oxygen -Burns -Toxic gases -Natural causes? 29 29 Superficial burn injuries • We need to assess the depth of the burn to understand the nature of the heat. 30 30 15 31 31 Flash flame burns - 18wf 32 32 16 Hair can change color in fire • Gray brassy blond at 250°C • Brown red at 400°C • Black hair doesn’t change color • “Singed hair” 33 33 34 34 17 20wf, found on gravel road 35 35 20wf, found on gravel road 36 36 18 The six basic •Who questions: •What •When? •Where •Why •How 37 37 When? • Death certificates require we determine time of injury & death. • More important is the time of death relative to the time of fire (-i.e., were they alive in the fire?) –Carbon monoxide level –Soot in airways –Skin burns - reaction of body’s tissues 38 38 19 When? -what time did fire reach body? • Use any clues you can. • Fires can smolder for hours before their discovery. Smoldering fires produce more CO. 39 39 Time/destruction phases for average adult once the fire reaches 650°C (1200°F) • Early - skin slips & peels • 10 min - arms badly charred • 14 min - legs badly charred • 15 min - bones in face & arms start showing • 20 min - ribs & skull cranium begin showing • 25 min - shin bones begin showing • 35 min - thighs & shin bones exposed 40 40 20 Most house fires don’t exceed 650°C • Cremation requires 900-1000°C for over 1- 2 hours to ashen body. • Bones/fragments still remain - if you look you can find them in the remains of a fire. 41 41 • First 8-12 minutes - Temp rises to 500°C Typical house – still survivable fire • “Flashover”, with rapid rise to over 700°C (1300°F) – not survivable • Temp gradually declines as fuel and oxygen consumed. 42 42 21 When? -were they alive in fire? 43 43 44 44 22 Inhalation of products of the fire • Soot in airways and upper GI tract. • How far can passive diffusion get soot into the body? 45 45 45m • Found in burned car by RR crossing ~0300, 6-18. • No crash. • Fire started inside passenger compartment. • No gross soot in mouth? 46 46 23 47 47 Gross evidence of soot was minimal, but microscopic findings were conclusive. 48 48 24 49 49 50 50 25 51 51 52 52 26 Skull fractures • Fractures of the cranial bones (i.e., above the ears) may be from fire or trauma. 53 53 54 54 27 55 55 56 56 28 Injuries - premortem or postmortem? • Skin - location & magnitude • Pugilistic pose • Skull fractures (cranial v. basilar) • Intracranial bleed – Epidural blood – Subdural / subarachnoid blood • Crush injuries 57 57 21wf, found in apartment: 58 58 29 21wf, wispy soot, [CO]=28% 59 59 Basilar skull fractures • Fractures of the base of the skull are due to trauma, NOT the fire. 60 60 30 53wm, pilot of experimental plane 61 61 26bm, gasoline truck driver 62 62 31 The six basic •Who questions: •What •When •Where? •Why •How 63 63 Where? -Are the injuries consistent with the history? • Child found beside mother, both unconscious in their apartment, adjacent to burning apartment. • Fire never got into their apartment. • Baby’s [CO] = 52%. Mom’s [CO] = 38%. 64 64 32 The fire never reached this man… 65 65 25wm, in burned mobile home 66 66 33 The six basic •Who questions: •What •When •Where •Why? •How? 67 67 Why didn’t the victim escape? • Child - confused • Teen or adult - suspect another contributing factor: – Drugs/alcohol – Trauma/foul play • Elderly - look for a debilitating disease 68 68 34 • Cherry red discoloration of Carbon blood and tissues (rule out cyanide or monoxide - hypothermia) • Look for contributing factors (drugs &/or autopsy diseases) • When two or more people die suddenly and unexpectedly in a home or motor vehicle, be very suspicious of CO 69 69 “Assumption is the mother of all screw-ups” -Anonymous 70 70 35 71 71 Sources of burn injury • Flame (most common): – flash, direct, radiant • Solar / sunburn • Scald (hot liquids) • Contact with hot solids • Convection (Hot air or fluids) • Chemical • Friction • Electrical • Microwave 72 72 36 73 73 Sources of burn injury (i.e., how does the heat reach the body?): • Flame (most common): – flash, direct, radiant • Solar / sunburn • Scald (hot liquids) • Contact with hot solids • Convection (Hot air or fluids) • Chemical • Friction • Electrical • Microwave 74 74 37 Solar burns 75 75 76 76 38 77 77 Sources of burn injury (i.e., how does the heat reach the body?): • Flame (most common): – flash, direct, radiant • Solar / sunburn • Scald (hot liquids) • Contact with hot solids • Convection (Hot air or fluids) • Chemical • Friction • Electrical • Microwave 78 78 39 Hx: 11 month old child was testing the water in the tub as it was filling. 79 79 80 80 40 81 81 Skin Burns, partial thickness (1°-2°) from contact with hot liquids or solids (conduction) -from Moritz, AR, Am J Path 1947;23:695. • Temperature • Time – 120°F (48.9°C) – 5 minutes – 125°F (51.7°C) – 1.5-2 minutes – 130°F (54.4°C) – 30 seconds – 135°F (57.2°C) – 10 seconds – 140°F (60.2°C) – 5 seconds – 145°F (62.8°C) – 3 seconds – 150°F (65.6°C) – 1.5 seconds – 155°F (68.3°C) – 1 second – 160°F (71°C) – 1 second to full thickness (3rd degree) 82 82 41 Hx: 8yo boy found in basement 83 83 84 84 42 85 85 86 86 43 87 87 88 88 44 Check the water level and possible splash-marks 89 89 “Stocking sign” 90 90 45 “Donut sign” 91 91 7yo girl 92 92 46 Sources of burn injury (i.e., how does the heat reach the body?): • Flame (most common): – flash, direct, radiant • Solar / sunburn • Scald (hot liquids) • Contact with hot solids • Convection (Hot air or fluids) • Chemical • Friction • Electrical • Microwave 93 93 94 94 47 Hx: child ‘brushed’ against lit cigarette 95 95 Dad claims the 11 month-old ‘walked across the stove’.Dad claims the 11 month- old walked across the stove.