CHRONOTATODIAGNOSIS: WHAT IS IT FOR, HOW IS IT DONE, EXAMPLE - MEDICINE - 2025

The cronotanatodiagnóstico is a specialty of forensic science whose objective is to estimate the approximate time that a death occurred. Although most deaths occur in controlled settings (home, hospital, asylum) and in the presence of witnesses who can fairly accurately certify the time of evolution of death (in hours, days and even months), in some cases it is necessary to determine the approximate time of death through the chronotanatodiagnosis.

This may be because the death occurred without eyewitnesses or because for legal medical reasons, suspicion of crime or inconsistency between different versions about the time of death, it is necessary to confirm the information provided by the witnesses.

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Although any certified physician has the basic knowledge to establish an approximate time frame during which a person died, only forensic professionals have the training, experience and tools necessary to be able to determine with an acceptable degree of certainty how long an individual has been dead.

Etymology

The word chronotanatodiagnosis is the product of the combination of two Greek voices and a word in Spanish:

- Cronos = Time (in Greek)

- Thanatos = Death (in Greek)

- Diagnosis

By combining the three, chronotanodiagnosis can be defined as "the time of death diagnosis."

What is it for

The information obtained through chronotanatodiagnosis is essential in forensic investigations related to the death of a person, since it allows creating a more or less precise time line between the cadaverous events and the rest of the evidence collected during the investigation (testimonies, videos surveillance, physical evidence, etc).

Thus, it is possible to determine whether the time or day of death indicated by the witnesses corresponds to the evolution time of a corpse or to determine how long a person previously reported as missing has been dead.

On the other hand, having a more or less accurate date and time of death makes it possible to confirm or rule out suspects in a criminal investigation by crossing the available information of such individuals with the timeline of the evolution of the corpse.

Scientific bases

The scientific basis that sustains the chronotanatodiagnosis derives from the detailed knowledge of the cadaveric phenomena and the time that these take to establish themselves.

In order to understand how the chronotanatodiagnostic process is, it is necessary to first understand the cadaveric phenomena that this science studies, for this reason we will proceed with a brief summary that covers the cadaveric phenomena in recent corpses (with less than 24 hours) and in non-recent ones (with more than 24 hours).

-Corpse phenomena in recent corpses

They are all the physical-chemical changes that a body experiences from the moment of death until the beginning of the putrefaction process, which on average begins 24 hours after death.

Cadaveric phenomena at this stage include:

Dehydration

The body begins to lose water through evaporation. It is an early phenomenon that can be evaluated by very obvious physical signs such as:

-Opacification of the cornea (begins at 45 minutes with eyes open and 24 hours with eyes closed).

-Lowering of the tension of the eyeball (starts at 15 hours postmortem)

-Playing and wrinkling of the skin (evident after 24 hours on the vulva, glans and lips, it varies significantly depending on the initial state of the corpse and the environmental conditions where it is found)

Decrease in body temperature

The decrease in body temperature begins as soon as vital functions cease, balancing the body temperature with that of the environment at approximately 24 hours postmortem.

During the first 6 to 8 hours the temperature drops at a rate of 0.8 - 1 ºC per hour and later at a rate of 0.3 - 0.5 ºC / hour until it is balanced with the external environment.

This can vary depending on the characteristics of the body, environment, presence or absence of clothing and a number of additional factors.

Cadaverous stiffness

It is the contraction of the striated muscle, beginning in the head and neck, descending towards the upper extremities, trunk and lower extremities.

It is due to the coagulation of myosin in muscle fibers; It begins approximately 3 hours after death and is completed between 18 and 24 hours later.

At approximately 24 hours the biochemical phenomena at the muscular level cease and the corpse loses its rigidity.

Cadaverous lightness

They are purple spots that appear in the most declining areas of the body due to the accumulation of body fluids.

The lividities begin between 3 and 5 hours after death and reach their maximum expression at approximately 15 hours.

The study of lividities allows not only to estimate the time of death, but also the position in which the body was left since the liquid will always go towards the declining areas.

-Corpse phenomena in non-recent corpses

They are all the cadaverous phenomena associated with the rotting process. Given that the decomposition of the body begins 24 hours after death, any corpse with signs of putrefaction is at least one day dead (sometimes longer depending on environmental conditions).

The stages of putrefaction allow the time of death to be estimated with some precision, although they usually present a greater margin of error when compared with the phenomena observed in the first 24 hours.

Chromatic phase

It is characterized by the appearance of greenish spots on the skin of the abdomen, it begins 24 hours after the evolution of the corpse and is due to the decomposition process initiated by bacteria located in the gastrointestinal tract.

Emphysematous phase

This stage is characterized by the production of gas that generates vesicles under the skin, swelling of the abdomen and escape of gases through natural orifices.

At this stage, the corpse is swollen and the normal configuration of certain anatomical regions such as the vulva and scrotum is lost, which reach unusual proportions.

The emphysematous phase begins approximately 36 hours after death and lasts up to 72 hours.

Coliquative phase

At this stage, all the gas has been released (normally the body opens spontaneously as a result of pressure) and the bacteria begin to digest the body, turning it into a shapeless mass with loss of morphological characteristics.

The coliquative phase begins at approximately 72 hours and lasts for a variable period that can extend for several days or even weeks depending on the conditions where the corpse is found.

Reductive phase

In this last phase, the corpse begins to shrink as a consequence of the processes of biological degradation, dehydration and chemical changes.

It usually lasts from several months to many years depending on the characteristics of the environment where the body is located.

How is it done

Knowing the scientific bases that support the chronotanatodiagnosis, it is very easy to get an idea of ​​the steps to follow in its execution.

First, the characteristics of the corpse, the position in which it is found, and the presence or absence of clothing on the body are observed.

After the first phase, the body is mobilized on an examination table or stretcher, the clothing is removed and a detailed study of the same begins.

The first thing is the general inspection of the body to determine if it is a recent corpse or not.

In the case of recent corpses, the eyes are evaluated including measurement of the intraocular pressure with a portable tonometer, in addition, lividities are looked for and the temperature of the body is measured both outside and inside, the most reliable temperature being that of the liver.

Simultaneously, the presence of cadaveric rigidity is evaluated. The combination of all the findings makes it possible to estimate an approximate time of death.

It is important to emphasize that it is an estimate given that to date there is no method that accurately indicates the evolution time of a corpse unless there is a medical record (witnessed death) or a video.

If it is a corpse with more than 24 hours of evolution, the phase of the decomposition process in which it is found will be determined by inspection.

Example

Security agencies are alerted to the presence of a lifeless body in a remote area of ​​the city.

Forensics appear in the area and proceed to locate the body, take a detailed note of its position and the conditions in which the body is, one of the most important being that the eyes are closed and there is no evidence of putrefaction.

They begin to collect data and find that:

- The pressure of the eyeball is normal

- Body temperature is 34 ºC

- There is marked stiffness in the muscles of the head and neck, mild in the upper extremities

- No lightness is identified

With this information, they determine that the person died between 4 and 6 hours before.

Obviously the previous one is just a basic example, in real life it is a much more complex process that requires a lot of dedication and work, but in general the final result will be similar (although more extensive) to the one presented.

References

1. Brown, A., Hicks, B., Knight, B., & Nokes, LDM (1985). Determination of time since death using the double exponential cooling model. Medicine, Science and the Law, 25 (3), 223-227.
2. Muggenthaler, H., Sinicina, I., Hubig, M., & Mall, G. (2012). Database of post-mortem rectal cooling cases under strictly controlled conditions: a useful tool in death time estimation. International journal of legal medicine, 126 (1), 79-87.
3. Madea, B., & Rothschild, M. (2010). The post mortem external examination: determination of the cause and manner of death. Deutsches Ärzteblatt International, 107 (33), 575.
4. Henssge, C., Brinkmann, B., & Püschel, K. (1984). Determination of the time of death by measurement of rectal temperature of corpses suspended in water. Zeitschrift fur Rechtsmedizin. Journal of legal medicine, 92 (4), 255-276.
5. Compton, AC (1974). Telling the time of human death by statute: an essential and progressive trend. Wash. & Lee L. Rev., 31, 521.
6. Henssge, C., Beckmann, ER, Wischhusen, F., & Brinkmann, B. (1984). Determination of the time of death by measurement of central brain temperature. Zeitschrift fur Rechtsmedizin. Journal of legal medicine, 93 (1), 1-22.
7. Knight, B. (1968). Estimation of the time since death: A survey of practical methods. Journal of the Forensic Science Society, 8 (2), 91-96.