Name 5 changes occurring 0-3h after death.
- warm and flaccid
- pallor but livor mortis soon observed (hypostasis)
- bladder may empty
- gastric contents regurgitated
- trucking of retinal blood vessels
Name 3 postmortem changes occurring 3-8 h after death
- warm and rigid
- Rigor Mortis
- livor mortis begins to develop
Factors influencing rigor mortis ? (4)
- exercise (faster)
- age: appear and disappear faster in children
- emaciated: difficult to determine
- temp: hotter = faster
- low muscle glycogen levels ( faster )
- electrocution faster
Name 2 PM changes at 8 - 36h
- cold and rigid
* algor mortis fully sets in
How long does algor mortis take to set in?
8 -12 h skin, core temp longer
What is the best estimator of time since death in first 24 h?
PMI (post mortem interval)- most accurate during intermediate phase where it drops linearly. Uses algor mortis. Pmi= body temp at death - body temp at exam.
Name 3 PM changes after 36 h
- Cold and flaccid
- putrefaction and decomposition
- skeletalisation
Name the 3 stages of putrefaction
- Initial decay (36/72 h - 1w) (abdo green discolor; bloat, blister, marbling of BVs on limbs and trunk, purge fluid)
- Black putrefaction (up to 1 mo) (organs liquefy - temp dependant)
- Dry decay then skeletonisation
If hypostasis colour is Cherry pink, what pathology can be suspected?
Carbon monoxide poisoning
If hypostasis colour is brick red, what pathology can be suspected?
Cyanide poisoning (and smell like hazelnut)
If hypostasis colour is golden brown, what pathology can be suspected?
Clostridium perfringens
Which biochemical factor can be used to estimate PMI?
Potassium concentration in vitreous. Increases PM. Must be carried out up till 5-7 days
Onset of rigor mortis?
3-4 hours after death. Face 1-4 h , limbs 3-6 h
When is rigor mortis fully established?
8-12 hours (textbook: 18 h )
Which term describes muscle stiffness with onset immediately at death, usually finding items gripped firmly in hands of deceased?
Cadaveric rigidity
In which patients may lividity be absent? (3)
• Extremes of age
• anemic
. Severe blood loss
Name 5 factors that may influence algor mortis
- Obesity (good insulator)
- emaciation (faster)
- Body posture
- body temp at time of death
- site of reading body temperature
- presence of clothing, type of material, position on body
- environmental temp and conditions - movement of air, humidity
- immersion water
Onset of decomposition?
3-4 days
Initial appearance of putrefaction?
Green discolor r iliac fossa ant abdominal wall. 3-4 days pm
Name 4 organs or tissues resistant to putrefaction initially
Prostate, uterus, tendons, ligaments
Describe process of decomposition (8)
• Green discolor right iliac fossa ant abdominal wall (cecum)
• marbling blood vessels - haemoglobin decompositions
• generalised skin discoloration
• superficial skin layers lose cohesion , blisters cont red/brown fluid form
• when blisters burst, skin sloughs off
• bloating face, abdo , breasts, genitals (gas)
. Protrusion eyes and tongue (increased int pressure ) causing purge fluid to leak from lungs, blood-stained
. Soft tissues liquefy
Then skeletalization.
What is adipocere?
Chemical change in body fat, hydrolysed to waxy soap -like compound
Conditions causing adipocere?
Wet conditions : immersion in water or bury in moist environment
Most useful method of estim time of death?
Henssge’s nomogram
