Estimating Time of Death PDF

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CHEM 1037 ...

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Estimating Time of Death ● Witness ● CCTV ● In hospital Algor Mortis ● A process that occurs after death in which the body temperature continually cools until it reaches the ambient or room temperature (performed at the scene as early as possible) ● After the death the body undergoes a process in which it continually adjust to equalize with the environmental temperature. ● Body loses heat at a rate of approximately 1-1.5℉ per hr ● Average room temperature is 70-72℉ ● The cooling rate can be used to estimate the time of death ● The rate of heat loss influenced by factors such as ambient (room) temperature, the size of the body, and the victim's clothing. → can only approximate the amount of time that has elapsed since death Livor Mortis ● A medical condition that occurs after death and results in the settling of blood in areas of the body close to the ground ● Tells us where the blood settles→ Gravity settles the blood→ it tells us whether the body has been moved or not. ● When the human heart stops pumping, the blood begins to settle in parts of the body closest to the ground (skin becomes a bluish-purple in those area) → this condition begins 20 min to 3 hrs after death and under average conditions continues for up to 16 hrs after death, at which point all livindity (or coloring) is fixed ● Different lividity patterns in a body may indicate that the body was moved after death but before livor mortis had fully fixed. ● The skin does not become discolored in areas where the body is restricted by wither clothing or an object pressing against the body. ● Livor that is deep purple is often seen in cases where the victim suffered asphyxia or heart failure Rigor Mortis ● A medical condition that occurs after death and results in the stiffening of muscle mass. The rigidity of the body begins within 24 hrs of death and disappears within 36 hrs of death (evolves over the first 24 hrs under average temperature and body conditions) ● Immediately following death, a chemical change occurs in the muscles that causes them to become rigid. ● The rigidity subsides as times goes on, and disappears after 36 hrs ● An environment that is hot can speed up the process significantly. Conditions that affected the body before death, such as exercise or physical activity, can also speed up the process.

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