Bodies from Water Flashcards
What is the definition of drowning
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
What is the incidence of drowning in the UK
Incidence 5.6 / 100 000 population
500 deaths each year in UK
What is the cause of the majority of drownings in the UK
66% are Accidental
33% are Suicide
Rarely homicidal
Where do most drownings in the UK occur
75% inland waters (includes baths)
25% sea
Why might someone drown
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
What scenarios have a high risk of accidental drowning
Intoxication Head injury Toddlers falling into water Children playing in rivers etc. Diving in shallow water Snorkeling & SCUBA diving Boating accidents Fishing
What clues suggest a suicidal drowning
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
Suicidal drowning is associated with what other factors
Alcohol and drugs
Makes it easier to carry out
Drowning is a common method of homicide - true or false
False
Rare as the actual method of homicide
Immersion in water is instead a common disposal/concealment method
How can a natural disease lead to drowning
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
Which underlying medical conditions put you at risk of drowning
Heart disease - MI, arrhythmias etc.
Epilepsy
When would a death be listed as ‘disease’ with contributory drowning
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
When would a death be listed as drowning with contributory ‘disease’
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
How might someone be drowned (murdered) in the bath
Can pull legs up sharply in bath to submerge face - very sudden and unexpected so causes death quickly
Reflex cardiac arrest if cold
Drowning is a diagnosis of exclusion - true or false
True
Drowning requires the person to be alive when entering the water - true or false
True
What 4 questions must be answered in the investigation of a body from water
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?
What is involved in an investigation of a body from water
Medical history Circumstances Recovery of the body Autopsy Toxicology & laboratory investigations Determine CoD
List some of the vital phenomena seen in drowning cases
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
List some of the artifacts of immersion seen in drowning cases
Injuries Gooseflesh - cutis anserina Washerwoman change - maceration Undressing Adipocere Skin pigmentation
Can occur whether alive or dead - just due to immersion
How can you estimate the duration of immersion
Body and water temperature - main factor used
Rigor mortis and cadaveric spasm
Hypostasis
Decomposition
How does body temperature change PM in water
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
What can prevent hypostasis in a drowned body
If the body is constantly moved by currents such as in turbulent sea
Blood doesn’t settle in same way
Can lividity still develop in water
Yes
It will correspond to the floating position
What can delay decomposition in water
Cold water temperature
Moving water currents
What can accelerate decomposition in water
Warm water temperature
Water pollution - increased bacteria and putrefaction
Water with wildlife - they eat the body
Bodies decompose faster in water than they do in air - true or false
False
Decompose approximately 50% slower than in air
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
At the same average temperature it would take around 2 weeks
Buried body would take 8 weeks
Describe the changes in the body after 12-30 hours immersion in water
Wrinkled fingers, palms and feet
Describe the changes in the body after 4-10 days immersion in water
Early decomposition in head, neck, abdomen & thighs
Describe the changes in the body after 2-4 weeks immersion in water
Bloating of face and abdomen
Venous marbling & peeling of epidermis on hands and feet
Scalp slippage
Describe the changes in the body after 1-2 months immersion in water
Gross skin shedding
Muscle loss
Exposure of skeleton
Describe the typical floating position of a body in water
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
The head dangles down when floating, what does this cause
Lividity in face
Injuries to prominences of face due to impact on rocks, etc. when washed along shallows
Abrasions etc.
What increases body buoyancy in water
Air trapping in the clothes
Specific Gravity of a body is similar to water - true or false
True
What decreases body buoyancy in water
Air in lungs being displaced by water
Heavy items in pockets or heavy clothing
Causes body to sink
Why do bodies resurface
Putrefactive gases form and refloat the body
Timing depends on water temperature but average is 1-2 weeks
What injuries may be present as artifacts of immersion
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
Injuries from rocks or river/sea beds occur on which parts of the body
Bony prominences
Typically abrasions
What is adipocere
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
What causes gooseflesh (cutis anserina)
Rigor mortis causes of erector pilli muscles causes hair to stand on end - piloerection
Also causes skin dimpling
Where do fish/crabs start eating on the body
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
What causes skin pigmentation in a body in water
Chromogenic bacteria
Causes it to become dark and blotchy
Areas of the body which remain above the water are vulnerable to what
Consumption by land animals - particularly rats
Seen in shallow water
Where does skin first begin to separate from the body
Around the nail beds and backs of fingers etc.
After this more of the skin starts to peel
Removing clothes from a body that has been in water for some time can cause what
Removal of the skin underneath
This is due to far gone washerwoman change
Can algae grow on the skin
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
How can you identify a body from water
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
What causes the diving response
Immersion of face in cold water
It is a protective reflex
Describe the diving response
Apnoea - stop breathing as a reflex (protective)
Peripheral vasoconstriction
Bradycardia
What causes the cold shock response
Sudden immersion in cold water
Not protective
Describe the cold shock response
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
How are the diving and the cold water response involved in drowning
They can compete and induce a cardiac arrhythmia
The cold water response alone can cause the same effect
How quickly does someone develop hypothermia in water
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
What happens when core body temperature drops to 34’C
Reduced conscious level
Aspiration of water
Person will drown
What happens when core body temperature drops below 28’C
Will go into ventricular fibrillation
Can lead to death in water
- not officially drowning
What happens when core body temperature drops below 24’C
Will go into asystole
Can lead to death in water - not officially drowning
List the phases of drowning (i.e. once they go under)
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
List the timings for the typical stages of drowning (not reliable, just a reference)
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
What are the mechanisms of death by drowning
Obstruction of airways by inhaled water
Or vagal inhibition (reflex cardiac arrest)
Laryngeal spasm
Hypothermia and exhaustion can also cause death with prolonged immersion
What happens when fresh water is aspirated
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
What happens when salt water is aspirated
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
How long does it take to drown in fresh water
4-5 minutes
Haemodilution leads to fluid overload
Fluid shift causes hyperkalaemia
How long does it take to drown in salt water
8-10 minutes
Mechanism is haemoconcentration
and absorption of Na, Cl into circulation (hypernatremia)
Prolonged resuscitation is often successful in drowning victims - true or false
True
The metabolism and O2 use is diminished so may come back after longer than usual
Especially true in children
How can immersion in water cause instantaneous death
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
In an instantaneous drowning death, the normal signs of drowning are still present - true or false
They are usually absent as it is so fast
What caused the foam in the airways in drowning cases
It is a mixture of water, air, mucus and surfactant which is whipped up by respiratory efforts
Describe the appearance of the airway foam seen in drowning cases
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
Foam in the airways is specific to drownings - true or false
False
Also seen in head injuries, epilepsy, overdoses and left ventricular failure
What causes emphysema aquosum
Active inspiration of air & water
Causes peripheral air trapping and hyperinflated lungs
Describe the appearance of emphysema aquosum
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
Where in the body is foreign material typically found after drowning
In airways, lungs, stomach
The presence of foreign material in the airways, lungs, stomach is suggestive of what
Submersion in the water when still alive
The debris is inhaled/swallowed in the process of drowning
Will foreign material be present inside the body if they were dead on entering the water
Complete absence of debris suggests rapid death or already dead
However, debris can still reach pharynx, trachea/bronchi & oesophagus in dead victim
What causes middle ear haemorrhage in drowning
Due to pressure changes or irritation via Eustachian tubes
Rare sign
How does middle ear haemorrhage appear
Blue discolouration in bony roof of middle ear
In which conditions can middle ear haemorrhage occur
Drowning
Head injury
Asphyxia
Electrocution
What causes venous congestion in drowning
Absorption of fresh water by pulmonary circulation
Fluid overload
What causes shoulder muscle bruising in drowning
Violent struggle tears pectoral and scaleni muscles
Causes haemorrhage = bruising
Why might foreign material be found in the hands of a drowning victim
Cadaveric spasm causes it to become trapped in the hands
May have been clutching at anything during the panic of drowning
List the laboratory tests used for drowning cases
Diatoms - most important
Specific gravity of blood in LV
Plasma Chloride
Plasma Magnesium
What are diatoms
Class of unicellular algae found in water
Secrete indestructible siliceous exoskeleton
When are diatoms found in drowning victims
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
List some complications of a near drowning experience
Acidosis and electrolyte disturbances Pulmonary oedema Haemolysis, haematuria and acute renal failure Pneumonitis and ARDS Bronchopneumonia
Why might someone die in the bath
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
List some of the hazards found in the bathroom that could be fatal
Falls (wet floor, hard surfaces leading to fatal injury)
Drowning (due to drugs, epilepsy, head injury)
Carbon Monoxide poisoning from faulty heater
Electrocution
Why might someone with a PE die in the bathroom
Often produces the sensation of needing to defecate so may die from PE in the bathroom
What is meant by bodies from water
Any death where the body has come out of water
Not just drowning
Includes being put in water after death
What are the possible causes of death in a body from water
accident
natural death
homicide
suicide
What are the Specific findings in the pm that suggest a suicidal drowning
There aren’t really any specific findings
Usually get more from history and circumstances (may even have witnesses)
What are the different outcomes related to natural disease with respect to drowning
- 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
If someone has CAD and collapsed dead into the water what would be the cause of death
Atherosclerotic coronary artery disease
List potential factors that mean a person cant survive/escape when they get into water
Natural disease
Trauma ( from assault, water or rocks)
Water too cold
Water too strong
If drowning is a diagnosis of exclusion what things do you need to exclude to make the diagnosis of downing
trauma as cause of death
drug/alcohol intoxication as cause of death
natural disease as cause of death
What is the difference between artifacts of immersion and vital phenomenon
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
If you recover a body from water and there is no wrinkling of the finger pads how long has it been immersed
Less than a few hours
What will contribute to defleshing of a body from water
Animal activity
Where do you get most lividity in drownings and why
Typically in the arms legs and head as they are the bits that dangle down in the floating position
Once the bodies comes out of water what happens to the rate of decomposition
Decomp slowed in water but as soon as it is taken it the decomposition will be accelerated
When may a body in water not resurface
If heavily weighed down
What does presence of adipocere suggest
That the body has been immersed for months - years
Describe the pattern of undressing that is an artefact of immersions and what does it suggest about the water
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
If a body from water has bruising associated with entry to the water what does it tell us
As they are bruised and that’s a vital phenomenon the person must have been alive when they hit the water
What does fish damage look like on a body
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
What is washerwoman change
Artefact of water immersion
Due to the skin absorbing water
It becomes white and thickened and wrinkled
Describe the progression of washerwoman change
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
When might you query sexual assault in a body from water
If body was found in still water
Undressing is normal in turbulent water but not common in still
What does adipocere look/feel like
It’s a white thick waxy material that may have clothing imprints in it
Which type of water will bodies last longest in before decomposing
Very still cold water that’s dark ( no fish) and fresh water
How do the effects fresh water and sea water in the lungs differ
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
How will sea water and fresh water effect the blood volume respectively
sea - hypovolaemia
fresh - hypervolaemia
Why do you get pulmonary oedema in drownings
Because you loose surfactant and can go into heart failure
Is sea water or fresh water inhalation more dangerous - why
Fresh
It causes hyperkalaemia and VF
Will the foam seen in drowning still be present at autopsy
Maybe
It is seen immediately on recovery of body but will start to dissipate and may be gone by day of autopsy
Why do you get pneumonitis, ARDS and bronchopneumonia in near drownings
If the water isn’t clean it can introduce bacteria
Why do you get haemolysis and hb-uria and acute renal failure subsequently in near drownings
Occurs after near drowning in fresh water
Caused by movement of the water into the pulmonary circulation - fluid shift
Why do you get acidosis and electrolyte disturbances in near drownings
Occurs if it was in sea water due to the Na and Cl being absorbed into the blood stream
How can you differentiate blunt force injury from assault and BFI from hitting the water
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
