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Flashcards in Bodies from Water Deck (120)
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1
Q

What is the definition of drowning

A

Death due to submersion in liquid (of nose/mouth)

Suffocation (asphyxia) caused by a liquid entering the lungs and preventing the absorption of oxygen leading to cerebral hypoxia and cardiac arrest

2
Q

What is the incidence of drowning in the UK

A

Incidence 5.6 / 100 000 population

500 deaths each year in UK

3
Q

What is the cause of the majority of drownings in the UK

A

66% are Accidental
33% are Suicide
Rarely homicidal

4
Q

Where do most drownings in the UK occur

A

75% inland waters (includes baths)

25% sea

5
Q

Why might someone drown

A

Natural death in the bath - e.g. MI that made them pass out and go under
Accident - e.g. fell into water and couldn’t get out
Suicide
Homicide

6
Q

What scenarios have a high risk of accidental drowning

A
Intoxication
Head injury
Toddlers falling into water 
Children playing in rivers etc.
Diving in shallow water
Snorkeling & SCUBA diving
Boating accidents
Fishing
7
Q

What clues suggest a suicidal drowning

A

History of suicidal intent - depression
Suicide note
Clothes may be left - old-fashioned phenomena
Ligatures and weights may be present - weights way more common
Suitable typical locations - bridges/piers
Often have injuries from impact with water - due to jump from height

8
Q

Suicidal drowning is associated with what other factors

A

Alcohol and drugs

Makes it easier to carry out

9
Q

Drowning is a common method of homicide - true or false

A

False
Rare as the actual method of homicide
Immersion in water is instead a common disposal/concealment method

10
Q

How can a natural disease lead to drowning

A

May collapse from the disease and then fall into water
Or go under if already in water such as swimming/in bath

The condition may be triggered by hot bath or exertion of swimming and have same effect

Can also weaken the person so they cannot swim for long periods of time and they drown

11
Q

Which underlying medical conditions put you at risk of drowning

A

Heart disease - MI, arrhythmias etc.

Epilepsy

12
Q

When would a death be listed as ‘disease’ with contributory drowning

A

If the victim had a non fatal disease event such as arrhythmia but this caused them to drown (as result of the event itself)
e.g. it caused a loss of consciousness

13
Q

When would a death be listed as drowning with contributory ‘disease’

A

If the person entered water (e.g. falls in or is swept away) and drowns due to the disease weakening them - e.g. lack of cardiac reserve due to heart disease
May have survived if they didn’t have underlying health problems

14
Q

How might someone be drowned (murdered) in the bath

A

Can pull legs up sharply in bath to submerge face - very sudden and unexpected so causes death quickly
Reflex cardiac arrest if cold

15
Q

Drowning is a diagnosis of exclusion - true or false

A

True

16
Q

Drowning requires the person to be alive when entering the water - true or false

A

True

17
Q

What 4 questions must be answered in the investigation of a body from water

A

Was the victim alive or dead on entering the water?

What was the cause of death? - drowning or other

Why was the victim in the water?

Why was victim unable to escape or survive?

18
Q

What is involved in an investigation of a body from water

A
Medical history
Circumstances
Recovery of the body
Autopsy 
Toxicology & laboratory investigations
Determine CoD
19
Q

List some of the vital phenomena seen in drowning cases

A
Foam in airways
Emphysema aquosum
Foreign material inhaled /swallowed  - sand/seaweed
Shoulder muscle/girdle bruising
Middle ear haemorrhage

May also have venous congestion and foreign material in hands

All mean they were alive when they were in water and is suggestive of drowning

20
Q

List some of the artifacts of immersion seen in drowning cases

A
Injuries
Gooseflesh - cutis anserina
Washerwoman change - maceration
Undressing 
Adipocere
Skin pigmentation 

Can occur whether alive or dead - just due to immersion

21
Q

How can you estimate the duration of immersion

A

Body and water temperature - main factor used
Rigor mortis and cadaveric spasm
Hypostasis
Decomposition

22
Q

How does body temperature change PM in water

A

It depends on the temperature of the water
General rule: naked body cools x2 faster than in air
Cooling is accelerated by moving water/currents
Slowed by presence of clothing

23
Q

What can prevent hypostasis in a drowned body

A

If the body is constantly moved by currents such as in turbulent sea
Blood doesn’t settle in same way

24
Q

Can lividity still develop in water

A

Yes

It will correspond to the floating position

25
Q

What can delay decomposition in water

A

Cold water temperature

Moving water currents

26
Q

What can accelerate decomposition in water

A

Warm water temperature
Water pollution - increased bacteria and putrefaction
Water with wildlife - they eat the body

27
Q

Bodies decompose faster in water than they do in air - true or false

A

False

Decompose approximately 50% slower than in air

28
Q

How long would it take a body immersed in water to reach the same level of decomposition as a body exposed to just air for a week

A

At the same average temperature it would take around 2 weeks

Buried body would take 8 weeks

29
Q

Describe the changes in the body after 12-30 hours immersion in water

A

Wrinkled fingers, palms and feet

30
Q

Describe the changes in the body after 4-10 days immersion in water

A

Early decomposition in head, neck, abdomen & thighs

31
Q

Describe the changes in the body after 2-4 weeks immersion in water

A

Bloating of face and abdomen
Venous marbling & peeling of epidermis on hands and feet
Scalp slippage

32
Q

Describe the changes in the body after 1-2 months immersion in water

A

Gross skin shedding
Muscle loss
Exposure of skeleton

33
Q

Describe the typical floating position of a body in water

A

Face down with head dangling downwards
Chest and abdomen most buoyant - closest to surface
Face down as lungs at back
Arms and legs dangle downwards - heavy

34
Q

The head dangles down when floating, what does this cause

A

Lividity in face
Injuries to prominences of face due to impact on rocks, etc. when washed along shallows
Abrasions etc.

35
Q

What increases body buoyancy in water

A

Air trapping in the clothes

36
Q

Specific Gravity of a body is similar to water - true or false

A

True

37
Q

What decreases body buoyancy in water

A

Air in lungs being displaced by water
Heavy items in pockets or heavy clothing

Causes body to sink

38
Q

Why do bodies resurface

A

Putrefactive gases form and refloat the body

Timing depends on water temperature but average is 1-2 weeks

39
Q

What injuries may be present as artifacts of immersion

A

Injuries from entry impact - from water or objects in water
e.g. rib fractures
Injuries such as abrasion/laceration from rocks, river bed etc.
Fish and crab activity

40
Q

Injuries from rocks or river/sea beds occur on which parts of the body

A

Bony prominences

Typically abrasions

41
Q

What is adipocere

A

Fat in the body is converted into a waxy substance - adipocere
This preserves the body to some extent - particularly fatty regions like cheek and neck
May see imprints of clothing that used to be there

42
Q

What causes gooseflesh (cutis anserina)

A

Rigor mortis causes of erector pilli muscles causes hair to stand on end - piloerection
Also causes skin dimpling

43
Q

Where do fish/crabs start eating on the body

A

They usually start eating bits that stick out such as ears, eyelids, lips, nipples etc.
This is because these are the only place they can get purchase
Also around lines where clothes would’ve been - don’t eat sites covered by clothes
They will expand out from here

44
Q

What causes skin pigmentation in a body in water

A

Chromogenic bacteria

Causes it to become dark and blotchy

45
Q

Areas of the body which remain above the water are vulnerable to what

A

Consumption by land animals - particularly rats

Seen in shallow water

46
Q

Where does skin first begin to separate from the body

A

Around the nail beds and backs of fingers etc.

After this more of the skin starts to peel

47
Q

Removing clothes from a body that has been in water for some time can cause what

A

Removal of the skin underneath

This is due to far gone washerwoman change

48
Q

Can algae grow on the skin

A

Yes - can grow on exposed skin (not clothed)
Particularly if the body is in fresh water in the Summer months
It can be scraped off

49
Q

How can you identify a body from water

A

Circumstances - where found, missing persons
Personal effects on body
Fingerprints
DNA
Dental - matched to AM records
X-Rays - identifying abnormalities, previous injury/operations, prothesis
Missing organs - suggest appendectomy etc.
May use tattoos if still present

50
Q

What causes the diving response

A

Immersion of face in cold water

It is a protective reflex

51
Q

Describe the diving response

A

Apnoea - stop breathing as a reflex (protective)
Peripheral vasoconstriction
Bradycardia

52
Q

What causes the cold shock response

A

Sudden immersion in cold water

Not protective

53
Q

Describe the cold shock response

A

There is a sudden cooling of skin which causes a reflex gasp
Hyperventilation - breathlessness makes it hard to swim
Breath holding time reduces to around 20s
Increased HR and BP - may induce arrhythmias

54
Q

How are the diving and the cold water response involved in drowning

A

They can compete and induce a cardiac arrhythmia

The cold water response alone can cause the same effect

55
Q

How quickly does someone develop hypothermia in water

A

Based on average adult wearing outdoor clothing cooling to 35’C (classed as hypothermia)

  • 1 hour if water temp of 5’C
  • 2-3 hours if water temp 10’C
  • 3-6 hours if water temp 15’C
56
Q

What happens when core body temperature drops to 34’C

A

Reduced conscious level
Aspiration of water
Person will drown

57
Q

What happens when core body temperature drops below 28’C

A

Will go into ventricular fibrillation
Can lead to death in water
- not officially drowning

58
Q

What happens when core body temperature drops below 24’C

A

Will go into asystole

Can lead to death in water - not officially drowning

59
Q

List the phases of drowning (i.e. once they go under)

A

The struggle against water subsides with exhaustion and drowning starts
Hold breath but the rising CO2 stimulates inhalation
Then person will start gulping, coughing, vomiting and then will become unconscious
Then convulsions and involuntary respiratory movements occur
Death occurs within few minutes

60
Q

List the timings for the typical stages of drowning (not reliable, just a reference)

A

1 - Surprise/panic lasts 5-10 seconds
2- 1st stage respiratory arrest after 1 minute
3- Deep respiratory efforts in next 1 minute
4- 2nd stage respiratory arrest lasts next 1 minute
5 - Terminal gasping
6 - Death after 3.5 – 4 mins

61
Q

What are the mechanisms of death by drowning

A

Obstruction of airways by inhaled water

Or vagal inhibition (reflex cardiac arrest)
Laryngeal spasm

Hypothermia and exhaustion can also cause death with prolonged immersion

62
Q

What happens when fresh water is aspirated

A

Inhaled hypotonic water (less salt than blood) in alveoli is absorbed into pulmonary capillaries
This causes haemodilution and hypervolemia
This results in hyponatraemia and hyperkalaemia (caused by haemolysis as K+ released)
The hyperkalaemia can induce VF

63
Q

What happens when salt water is aspirated

A

Inhaled hypertonic water (more salt than blood) in alveoli draws fluid from pulmonary capillaries
This causes haemoconcentration and hypovolemia
The Na and Cl are absorbed into blood which leads to hypernatremia

64
Q

How long does it take to drown in fresh water

A

4-5 minutes
Haemodilution leads to fluid overload
Fluid shift causes hyperkalaemia

65
Q

How long does it take to drown in salt water

A

8-10 minutes
Mechanism is haemoconcentration
and absorption of Na, Cl into circulation (hypernatremia)

66
Q

Prolonged resuscitation is often successful in drowning victims - true or false

A

True
The metabolism and O2 use is diminished so may come back after longer than usual
Especially true in children

67
Q

How can immersion in water cause instantaneous death

A

Fatal form of the cold-shock response due to sudden and unexpected immersion in cold water
Causes a reflex cardiac arrest through vagal inhibition
No struggle as so fast
Going feet first may exacerbate due to effect of water shooting up nose
Alcohol can make this reflex hypertensive

68
Q

In an instantaneous drowning death, the normal signs of drowning are still present - true or false

A

They are usually absent as it is so fast

69
Q

What caused the foam in the airways in drowning cases

A

It is a mixture of water, air, mucus and surfactant which is whipped up by respiratory efforts

70
Q

Describe the appearance of the airway foam seen in drowning cases

A

It is a fine white froth
Can be found externally at nostrils and mouth
More may appear on resus - compression of chest
Internally it can be found in the trachea and bronchi

71
Q

Foam in the airways is specific to drownings - true or false

A

False

Also seen in head injuries, epilepsy, overdoses and left ventricular failure

72
Q

What causes emphysema aquosum

A

Active inspiration of air & water

Causes peripheral air trapping and hyperinflated lungs

73
Q

Describe the appearance of emphysema aquosum

A
Lungs will be voluminous and ballooned
May even be overlapping over the heart
Pleural surfaces have marbled appearance
Doughy texture, pitting on fingertip pressure
Have crepitus on pressing
Histological distension of alveoli
74
Q

Where in the body is foreign material typically found after drowning

A

In airways, lungs, stomach

75
Q

The presence of foreign material in the airways, lungs, stomach is suggestive of what

A

Submersion in the water when still alive

The debris is inhaled/swallowed in the process of drowning

76
Q

Will foreign material be present inside the body if they were dead on entering the water

A

Complete absence of debris suggests rapid death or already dead
However, debris can still reach pharynx, trachea/bronchi & oesophagus in dead victim

77
Q

What causes middle ear haemorrhage in drowning

A

Due to pressure changes or irritation via Eustachian tubes

Rare sign

78
Q

How does middle ear haemorrhage appear

A

Blue discolouration in bony roof of middle ear

79
Q

In which conditions can middle ear haemorrhage occur

A

Drowning
Head injury
Asphyxia
Electrocution

80
Q

What causes venous congestion in drowning

A

Absorption of fresh water by pulmonary circulation

Fluid overload

81
Q

What causes shoulder muscle bruising in drowning

A

Violent struggle tears pectoral and scaleni muscles

Causes haemorrhage = bruising

82
Q

Why might foreign material be found in the hands of a drowning victim

A

Cadaveric spasm causes it to become trapped in the hands

May have been clutching at anything during the panic of drowning

83
Q

List the laboratory tests used for drowning cases

A

Diatoms - most important
Specific gravity of blood in LV
Plasma Chloride
Plasma Magnesium

84
Q

What are diatoms

A

Class of unicellular algae found in water

Secrete indestructible siliceous exoskeleton

85
Q

When are diatoms found in drowning victims

A

Found in bone marrow, liver and brain if blood was still circulating when in the water
Vital phenomena
Specific diatoms live in specific areas of water so they can be compared to see where they drowned

May also be introduced through contaminated water/food in vivo so not exact

86
Q

List some complications of a near drowning experience

A
Acidosis and electrolyte disturbances
Pulmonary oedema
Haemolysis, haematuria and acute renal failure
Pneumonitis and ARDS
Bronchopneumonia
87
Q

Why might someone die in the bath

A

Murder - drowned
Drug addicts sometimes placed in bath after overdose - try to wake them up
Suicidal incision often performed in bath
Accidental death - drugs, epilepsy, falls etc.
Death from natural disease

88
Q

List some of the hazards found in the bathroom that could be fatal

A

Falls (wet floor, hard surfaces leading to fatal injury)
Drowning (due to drugs, epilepsy, head injury)
Carbon Monoxide poisoning from faulty heater
Electrocution

89
Q

Why might someone with a PE die in the bathroom

A

Often produces the sensation of needing to defecate so may die from PE in the bathroom

90
Q

What is meant by bodies from water

A

Any death where the body has come out of water
Not just drowning
Includes being put in water after death

91
Q

What are the possible causes of death in a body from water

A

accident
natural death
homicide
suicide

92
Q

What are the Specific findings in the pm that suggest a suicidal drowning

A

There aren’t really any specific findings

Usually get more from history and circumstances (may even have witnesses)

93
Q

What are the different outcomes related to natural disease with respect to drowning

A
  • natural disease kills you first then you happen to collapse into the water
  • natural disease means you collapse alive into the water and then drown
  • natural disease means that once in water you couldn’t escape/survive as well = drowning
  • person ended up in water and drowned normally and just happens to have an underlying disease but it doesn’t contribute to the drowning
94
Q

If someone has CAD and collapsed dead into the water what would be the cause of death

A

Atherosclerotic coronary artery disease

95
Q

List potential factors that mean a person cant survive/escape when they get into water

A

Natural disease
Trauma ( from assault, water or rocks)
Water too cold
Water too strong

96
Q

If drowning is a diagnosis of exclusion what things do you need to exclude to make the diagnosis of downing

A

trauma as cause of death
drug/alcohol intoxication as cause of death
natural disease as cause of death

97
Q

What is the difference between artifacts of immersion and vital phenomenon

A

Vital phenomena only occur in the living so would only be seen PM if the victim was alive when they entered the water

Artefacts of immersion occur irrespective of if the victim was alive or dead when they entered the water

98
Q

If you recover a body from water and there is no wrinkling of the finger pads how long has it been immersed

A

Less than a few hours

99
Q

What will contribute to defleshing of a body from water

A

Animal activity

100
Q

Where do you get most lividity in drownings and why

A

Typically in the arms legs and head as they are the bits that dangle down in the floating position

101
Q

Once the bodies comes out of water what happens to the rate of decomposition

A

Decomp slowed in water but as soon as it is taken it the decomposition will be accelerated

102
Q

When may a body in water not resurface

A

If heavily weighed down

103
Q

What does presence of adipocere suggest

A

That the body has been immersed for months - years

104
Q

Describe the pattern of undressing that is an artefact of immersions and what does it suggest about the water

A

Tops go up over head and off arms sometimes
Trousers are pulled down to ankles and will come of if shoes removed
Suggests turbulent water over still water

105
Q

If a body from water has bruising associated with entry to the water what does it tell us

A

As they are bruised and that’s a vital phenomenon the person must have been alive when they hit the water

106
Q

What does fish damage look like on a body

A

Starts of as just small areas of epidermis being removed and then if gone on for long time it will get down to SC fat and whole bands of epidermis are removed
Around nipples the skin is often removed in perfect circles

107
Q

What is washerwoman change

A

Artefact of water immersion
Due to the skin absorbing water
It becomes white and thickened and wrinkled

108
Q

Describe the progression of washerwoman change

A

After a few hours it’s thickened, white, wrinkled skin
If left longer you get separation at the dermo-epi junction and skin slippage/peeling
This typically starts around the nails and then more of the skin peels off

109
Q

When might you query sexual assault in a body from water

A

If body was found in still water

Undressing is normal in turbulent water but not common in still

110
Q

What does adipocere look/feel like

A

It’s a white thick waxy material that may have clothing imprints in it

111
Q

Which type of water will bodies last longest in before decomposing

A

Very still cold water that’s dark ( no fish) and fresh water

112
Q

How do the effects fresh water and sea water in the lungs differ

A

Fresh water is hypotonic (to blood) so water is absorbed into the pulmonary circulation

In seawater its hypertonic so it absorbs water from the pulmonary circulation

113
Q

How will sea water and fresh water effect the blood volume respectively

A

sea - hypovolaemia

fresh - hypervolaemia

114
Q

Why do you get pulmonary oedema in drownings

A

Because you loose surfactant and can go into heart failure

115
Q

Is sea water or fresh water inhalation more dangerous - why

A

Fresh

It causes hyperkalaemia and VF

116
Q

Will the foam seen in drowning still be present at autopsy

A

Maybe

It is seen immediately on recovery of body but will start to dissipate and may be gone by day of autopsy

117
Q

Why do you get pneumonitis, ARDS and bronchopneumonia in near drownings

A

If the water isn’t clean it can introduce bacteria

118
Q

Why do you get haemolysis and hb-uria and acute renal failure subsequently in near drownings

A

Occurs after near drowning in fresh water

Caused by movement of the water into the pulmonary circulation - fluid shift

119
Q

Why do you get acidosis and electrolyte disturbances in near drownings

A

Occurs if it was in sea water due to the Na and Cl being absorbed into the blood stream

120
Q

How can you differentiate blunt force injury from assault and BFI from hitting the water

A

When you are assaulted the skin bruises as well as internally
When you hit the water the skin doesn’t typically bruise as you enter but it will cause internal damage causing internal bruising/haemorrhage