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Early Changes After Death

Death is defined as the cessation of all vital functions of the body including the heartbeat, brain activities (including the brain stem) and breathing. Death may come in many forms whether it is expected (eg. after a diagnosis of terminal illness) or unexpected (eg. accidents or medical conditions). It is also defined as irreversible loss of function of an organism as a whole. Upon the occurance of death, there are certain changes that occur to the body. The changes that occur are divided into early changes and late changes. Changes in the skin, changes in the eye, algor mortis or decrease in body temperature, rigor mortis and livor mortis are changes that involved in early changes of death. In late changes of death, decomposition, formation of adipocere or mummification occur.

Changes to the skin

When death occurs, the first change that can be observed on the skin of the deceased are from the skin colour and elasticity of the skin itself. The elasticity of the skin is lost gradually and the skin becomes pallor.

Changes to the eye

Changes to the eyes can be seen by testing the reflexes of the pupils and cornea of the eye. After death, there is are no reflexes of the pupils to light  and the cornea also loses its reflex. The cornea of the deceased also become cloudy after two hours of death. Besides that, the pressure in the eyes start to decrease and the eyeballs become flaccid before it they sink into the orbits of the eyes.

Algor Mortis

Algor mortis, also known as cooling of the body, is one of the changes that occur in early changes of death when the temperature of the body start to decrease. It is a complex process, which do not occur at the same rate throughout the body. Under average conditions, the body cools at the rate of about 2.0 – 2.5 degrees Farenheit per hour during the first few hours after death and slower afterwards. The temperature can decrease by radiation, convection, and as well as conduction process. There are a few factors that affect the rate of cooling of the body, such as the age of the deceased, condition of the deceased, manner of death, environment temperature as well as the condition of the environment where death had occured.

The rate of cooling of the body, is quicker if the deceased is a child as compared to an adult  Children have a larger body surface area compared to the volume of the body. Besides that, body build and clothing also give a significant effect to this process. Obesity slows cooling because of the insulation by the body fat. The rate of temperature decrease is higher if the deceased is dressed in light clothing or naked as compared to dressed in heavy clothing.

Other than that, significant difference between environmental temperature and body temperature increases the rate of cooling of the body. For bodies found in water, the decrease of body temperature is influenced by water conditions, water temperature and water flow.  Dirty water make the body temperature drops slower as the activity of the bacteria present in the water can raise the body temperature.

Rigor Mortis

Besides algor mortis, the body of the decease will also go through a phase called rigor mortis. Rigor mortis is a condition in which the body gradually becomes stiff after death takes place. This condition usually happens in the first 1-2 hours after death and the stiffening of the body gradually lost and ends after 48 hours. The stiffening of the body is caused by chemical reaction which occur to muscles when consumption of oxygen decrease in production of Adenosine Tri phosphate (ATP) and thus the muscles contract.

Factors that influence rigor mortis include age of the deceased, the activity done by the deceased prior to death, environmental temperature when death takes place and the deceased body build. Signs of rigor mortis do not appear if death happens in temperature of 6 degree celsius. Instead, cold stiffening will occur. As the environmental temperature increase, rigor mortis appear and disappear faster.  Conversely, lower temperature slowdown the rigor mortis until it gradually disappears.

In situation where the deceased was in an active state before death occured, (for example, the deceased involved in a struggle), process of rigor mortis  rapidly occurs due to loss of ATP in large amount during the struggle.

The lack of muscles in the body could affect the rate of progress of rigor mortis process. Rigor mortis occur more rapidly in infants, elderly and small body build compared to large body build deceased.


Figure 1 : Rigor Mortis

Livor Mortis

Livor mortis also known as postmortem lividity or postmortem hypostasis. It is defined as settling of the blood in dependent portions of the body except in areas exposed to pressure. It begins after death where the blood sinks by gravity to the dependent region of the body. Small blood vessels in those areas become very congested with blood. This postmortem lividity can be identified by the red purple colour at the area of the body involved.

The location of the livor mortis depends on the position of the body during death. If the deceased is in supine position, the hypostasis will appear at the back side except for the area that is touching the surface such as the buttocks and scapula.

As we can observe in poisoning case, the hypostasis colour significantly depends on the poison involved in the death. In this situation, the colour provides us information of posibble types of poison used in cessation of life activity which leads to determination of cause of death. Death due to cyanide poisoning gives dark blue to pink colouration to the livor, while in carbon monoxide poisoning, cherry red colour is noticed. Livor mortis starts to occur 1-3 hours after cessation of life takes place.

In medicolegal cases, livor mortis is important to help estimate the time of death, confirming the death as well as it to give information on the last position of the decease.


Figure 2 : Livor mortis

The early changes that occur after death helps in estimation of time since death as well as for death confirmation. Furthermore, it is useful in the investigation of the cause of death and gives information on the last position held by the deceased before death. After all the early changes after death take place, late changes such as decomposition of the body, adipocere formation and mummuification will begin.

References

  1. http://forensicpathologyonline.com/e-book/post-mortem-changes/cooling-body
  2. http://www.centralia.edu/academics/forensicscience/FORS%20101/PowerPointPres/TDeathInvest.ppt
  3. www.harriscountry.gov/ifs/cause.aspx
  4. http://webpages.sou.edu/chapman/CH300S10/ForensicPathology%202%20(student).ppt
  5. http://lontar.ui.ac.id/
  6. Postmortem Changes Powerpoint Presentation by Dr Amir Saad,Forensic Pathologist,HKL
  7. Postmortem Changes and Time of Death Powerpoint presentation by Ms. Anne Cuppero, University of New Orleans
  8. William A.Cox, Early Postmortem Changes and Time of Death,December 22,2009.
  9. Shahrom Abd. Wahid,Patologi Forensik, Dewan Bahasa & Pustaka, 2001.

Picture References

  1. Postmortem Changes Powerpoint Presentation by Dr Amir Saad,Forensic Pathologist,HKL
  2. Shahrom Abd. Wahid,Patologi Forensik, Dewan Bahasa & Pustaka, 2001

 

Last Reviewed : 2 July 2014
Writer / Translator : Suhailey bt. Mohd Noor
Accreditor : Dr. Nor Zaimah bt. Mohamad Idris