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Livor Mortis
| Evident |
30 min – 2 hrs. |
| Fixed |
8 – 12 hrs. (24 – 36 hrs if cool) |
| Tardieu spots |
18 – 24 hrs.(2 – 4 hrs in hanging limbs) |
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Rigor Mortis
| Cadaveric spasm |
heavy exercise, convulsions, high body temps |
| Evident |
2 – 4 hrs. (jaw, upper then lower extremities) |
| Maximum |
6 – 12 hrs. |
| Passes |
24 hrs (hot) – 36 hrs – 6 days (cold) |
| Accelerated |
infants, strychnine, convulsions, hyperthermia, drowning (struggle), |
Cutis anserino – rigor mortis of arrector pili muscles (gooseflesh). |
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Temperature
| Time since death = 37C – Rectal temp (C) + 3 |
| Time since death = (98.6F – Rectal temp (F)) / 1.5 |
Assumption that body temp at death was normal.
Can have postmortem rise in temp due to metabolic activity of body tissues & bacteria: may take up to 4 hrs to return to normal.
Consider effects of ambient temperature, clothing, body fat. |
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Decomposition
| Corneal clouding |
24 hrs. |
| Green belly |
24 – 36 hrs. |
| Marbling |
60 – 72 hrs. |
| Skeletonization |
Exposed remains 9-10 days |
| Mummification |
hot & dry |
| Adipocere |
damp & warm; immersed in water |
| Accelerated |
obesity, heavy clothing, sepsis |
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Gastric Emptying
| Light meal |
1.5 – 2 hrs. |
| Medium meal |
3 – 4 hrs. |
| Heavy meal |
4 – 6 hrs. |
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Insect Activity
Blowflies lay eggs immediately after death in daytime.
| Eggs |
1 – 2 days |
| Maggots to pupa |
6 – 10 days |
| Adult flies |
12 – 18 days |
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| Other Methods: Vitreous Potassium, Flow Cytometry for splenic DNA degradation (experimental) |
| Most accurate: Scene markers (mail, TV schedule, dress, last seen, receipts) |
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| Increase post-mortem: Vitreous K, Serum glucose in asphyxia, right heart or IVC |
| Decrease post-mortem: Vitreous glucose, Serum Na, Cl, glucose in left heart and extremities, |
| Stays stable post-mortem: Vitreous Na and Cl, VUN (most stable) |
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| Postmortem clot vs. antemortem clot. Postmortem looks like chicken fat & current jelly. Antemortem granular w/lines of Zahn |
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