Easing Distress When Death is Near

Joanne Wolfe MD, MPH , in Textbook of Interdisciplinary Pediatric Palliative Care , 2011

Livor mortis

One of the early changes that can be observed is livor mortis, also referred to as lividity, postmortem hypostasis, vibices, and suggilations. 38 This is a physical process. While the individual is alive, the heart circulates the blood. When death occurs, circulation stops and the blood begins to settle, by gravity, to the lowest portions of the body. This results in a discoloration of those lower, dependent parts of the body. Although beginning immediately, the first signs of livor mortis are typically seen about 1 hour following death, with full development being observed 2 to 4 hours following death. 38

Postmortem Changes: Overview

M. Tsokos , R.W. Byard , in Encyclopedia of Forensic and Legal Medicine (Second Edition), 2016

Patterned Appearance and Contact Blanching

Livor mortis is frequently patterned when its development is hindered by vessels in dependent parts of the body being compressed. This occurs when prominent parts of the body, such as areas over bony structures, press firmly onto an unyielding surface due to the weight of the body, or when tight clothing compresses the involved vessel lumina ( Figures 3 and 4(a) and (b)). In such areas, livor mortis is absent: the involved body surface appears pale to white, in contrast with the surrounding red/purple skin. This contact blanching may capture the shape and pattern of objects that were in contact with the dependent parts of the body surface during livor mortis formation, and occasionally the distinctive morphological appearance of contact blanching may give the death investigator valuable hints about the case in question (Figure 5).

Figure 3. Patterned appearance of livor mortis on the back.

Figure 4. Contact blanching from tight clothing (a and b).

Figure 5. Contact blanching on the back of a body outlining a pistol.

Creasing of the skin or tight clothing may produce contact blanching around the neck, which may resemble ligature marks (Figure 6). Therefore, knowledge of the position of the head and neck as well as the clothing worn at the time of death is important for the death investigator.

Figure 6. Contact blanching on the skin of the anterior neck, which should not be confused with a ligature mark.

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The Method Debate

Chawki Bisker , T. Komang Ralebitso-Senior , in Forensic Ecogenomics, 2018

Livor Mortis

Livor mortis starts immediately after the cessation of blood circulation. Adelson (1952) reported the appearance of minor signs on specific parts of the cadaver 30   min after death, which become fully discernible after 3–4   h and fixed in 8–12   h. In contrast, Polson (1985) stated that these first appear 30   min to 2   h after death and become completely developed after 6–12   h. Typically, the color shifts and patterns will often not disappear entirely even when the cadaver is transported or repositioned. Moreover, these are not normally observable on areas in contact with solid surfaces due to the compression of blood vessels (Krompecher, 2002). This highlights the utility of livor mortis in postmortem interval delimitation, death scenario reconstruction, and cause of death assessment, especially in cases such as hypothermia, carbon monoxide poisoning, and cyanide intoxication. The use of spectrophotometry, such as tristimulus colorimetry, was suggested by Vanezis and Trujillo (1996) for PMI estimation up to 48   h, while an equation was proposed by Usumoto et al. (2010) for time of death assessment within 72   h postmortem.

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TIME SINCE DEATH

A. Tracqui , in Encyclopedia of Forensic Sciences, 2000

Lividity

Postmortem lividity (hypostasis, livor mortis) is a plurifocal staining of the skin, usually in the form of a more or less intense purple discoloration, due to the gravitational settling of blood in vessels after the circulation has ceased. It always develops at the lowest parts of the cadaver, which depends upon its posture after death: in a body lying in the usual supine position, lividity predominantly affects the nape of the neck and the posterior aspects of trunk and limbs. By contrast, it does not appear on skin areas exposed to pressure, e.g. areas in contact with the underlying supporting surface (shoulder blades, buttocks, calves and heels for a body in the supine position), or areas squeezed by tightly fitting clothing (belts, underwear elastic).

Lividity often becomes perceptible within 3–4 h of death and progressively develops in surface area and colour intensity to attain its maximum degree 8–12 h postmortem. During this early period it is still mobile, i.e. it may be locally displaced by thumb pressure on the skin, or it can move (partly or completely) to other regions of the corpse if the body position is altered. After 12–15 h, postmortem hypostasis becomes 'fixed' and thus can no longer be displaced by external action. It will then remain unchanged until masked by the generally darker discoloration resulting from putrefaction.

Although this sign is present in almost all bodies (with the exception of those dying of massive hemorrhage), the time course of lividity exhibits considerable intersubject variability – probably to a greater extent than most other estimators of time of death in the early postmortem period. In addition, its quantitative measurement is imprecise (some authors use colorimetric tables) and in most routine cases its estimation remains largely subjective.

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Supravital Reactions in the Estimation of the Time Since Death (TSD)

Jarvis Hayman , Marc Oxenham , in Human Body Decomposition, 2016

Livor Mortis

Livor mortis or lividity is the gravitational pooling of blood in the dependent parts of the body, both externally in the skin capillaries and venules but also in the internal organs. Its onset is variable but it is usually most evident about 2  hours after death, although it is stated to occur as soon as 15   minutes after death (Clark et al., 1997). Initially the color is red but it later becomes purple as oxygen dissociates from the hemoglobin, changing it to purple-colored deoxyhemoglobin. This color change can be variable depending on the circumstances of death and the environment. Cold temperatures will delay the dissociation of oxygen from the hemoglobin, delaying the color change from red to purple. Carbon monoxide poisoning produces a persistent cherry red color and cyanide poisoning will also cause the red color to persist. Lividity may not be seen in bodies that are very anemic at death. Initially it is not fixed, that is, if pressure is applied to a skin area the red color changes to white as the blood is returned to the capillaries due to the pressure. Bodies lying on a hard surface will also show white blanching in the areas making contact with the surface for the same reason. Lividity is said to become fixed in 4–6   hours, that is, the red color no longer disappears on pressure because with cooling of the body, the fat surrounding the capillaries solidifies, constricting the capillaries and preventing the return of blood into them (Clark et al., 1997).

A reference to lividity occurs in the earliest extant comprehensive handbook for mid-13th-century Chinese forensic investigators into homicides and other deaths by Sung Tz'u. A clear description of lividity occurs toward the end of Sung Tz'u's (1186–1249) handbook: "Generally, dead persons have a slight red coloration on the back of the neck, on the top of the back, on the ribs, the back of the waist, the insides of the legs, the knees, the feet and the stomach. Check to determine if after death these corpses were laid out supine overnight. The collapse of the blood vessels may cause this slight red coloration, which does not indicate any other cause of death."

Turning to more recent times, the time sequence of livor mortis has been proposed as a method of estimating the TSD. However, the physiological mechanism of blood pooling, coagulation, and hemoglobin dissociation is so variable as to make it an unreliable method (Knight, 2002). The assessment by observation with the passage of time is subjective and therefore prone to observer error. Recently attempts have been made to quantify the hypostasis of lividity by colorimetry. A preliminary study carried out by Vanezis (1991), using a colorimeter, showed a linear relationship between the passage of time and the lightening color intensity when bodies showing lividity in dependent areas were turned over to enable blood to return to capillaries. Hypostasis reduced considerably even after 24   hours and slightly up to 3 days after death. In a follow-up study, Vanezis and Trujillo (1996) attempted to quantify the rate of change in the intensity of livor mortis with time by the use of a colorimeter. Ninety-three cadavers in whom the time of death was known to within 3   hours were subjected to colorimetric study. The bodies, kept at 4°C, were placed in the prone position and the degree of luminosity on their backs measured at 4-hourly intervals up to 72   hours. A strong correlation was found between the degree of luminosity and the postmortem interval (PMI), lividity becoming darker with increasing PMI in an exponential fashion. After 72   hours lividity became fixed. There were only a small number of cases in this series and the authors concluded that factors such as body size, cause of death, body position, environmental temperature, and especially skin color could affect the luminosity.

A simple colorimeter was developed by Masashi Inoue and colleagues (1994) to measure the change in intensity of postmortem lividity with the passage of time. The colorimeter transmitted and received light in the 600-nm wavelength region which was poorly absorbed by the water and melanin of the skin but was strongly absorbed by hemoglobin. The instrument was used to measure the intensity of lividity as pressure was applied to areas of maximum and minimum lividity in 42 corpses whose PMI was known, over a period of time until lividity became fixed. A strong correlation between the passage of time and the intensity of the livor mortis was found but there were variations caused by the same factors that others had noted, namely, body size, cause of death, posture, environmental temperature, and skin color. Kaatsch and colleagues (1994) measured pressure-induced blanching of livor mortis to estimate TSD with a digital system of photometric quantification on 50 cadavers in which the time of death was known. The authors used defined magnitudes of pressure, in contrast to subjective pressure by finger or forceps. They found distinct differences between the different time categories for pressure-induced color changes in lividity up to 40   hours post mortem, after which pressure no longer produced blanching. They also found that blanching could be produced for a longer period of time in bodies stored at a cooler temperature. There were wide variations in the data which they attributed to skin color, antemortem physical condition, cause of death, environmental factors such as ambient temperature, and storage conditions prior to measurement. The authors concluded that provided these factors were taken into account, and considering this was a small study, the findings provided a basis for further research to improve the measurement of lividity.

The quantitative measurements of livor mortis are only useful for 30–40   hours post mortem and before the changes of putrefaction have begun (Kaatsch et al., 1994). The rate of occurrence, intensity of coloration, distribution, and possible redistribution of lividity are so variable and difficult to standardize that they should not be used alone to estimate the postmortem period (Vanezis and Trujillo, 1996).

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A review of research concerning the estimation of time since death in decomposed bodies in the early stages of decomposition

Jarvis Hayman MB,ChB, FRCS(Ed), FRACS, MA(Hons) Archaeology, PhD , in Estimation of Time Since Death in Australian Conditions, 2021

1.1.1 Livor mortis

Livor mortis is the process where blood pools in dependent tissues following cessation of the circulation. It is first noticed as a purple discolouration beginning about 2  hours after death and for a period of time it is not fixed, that is an area of lividity subjected to pressure will become white, as the deoxygenated blood is pressed back into the capillaries. The area of lividity will also move to another dependent region if the body is moved during this period. After about 4–6   hours, it becomes fixed, that is the area does not blanch on pressure and does not shift with body position because capillaries in the dermis are occluded by the surrounding fat as it solidifies (Clark et al., 1997). Other observers have noted a different time sequence; lividity becoming apparent from 20   minutes to 2   hours after death, reaching maximum intensity in 6–9   hours and becoming fixed from 3 to 5 days (Vanezis and Trujillo, 1996). The appearance has been divided into categories: (1) beginning, (2) confluence, (3) maximum intensity, (4) slight pressure displacement, (5) complete shifting and (6) incomplete shifting (Swift, 2006). However, these categories are subjective, are dependent on individual qualitative assessment and are of little use in the quantitative estimation of the PMI.

A preliminary study to determine the degree of lividity by colorimetry and equating it with the PMI was carried out on 26 cadavers (Vanezis, 1991). In a larger study, 93 cadavers in whom the time of death was known to within 3   hours were subjected to colorimetric study (Vanezis and Trujillo, 1996). The bodies kept at 4°C were placed in the prone position and the degree of luminosity on their backs measured at four hourly intervals up to 72   hours. A strong correlation was found between the degree of luminosity and the PMI, lividity becoming darker with increasing PMI in an exponential fashion. After 72   hours lividity became fixed. There were only a small number of cases in this series and the authors concluded that factors such as body size, cause of death, body position, environmental temperature and skin colour could affect the luminosity.

A computer-aided system for measuring pressure-induced blanching of livor mortis as a means of estimating the TSD was described by Kaatsch et al. (1993). In a later study of 50 cadavers, photometric measurement was made of areas of post-mortem lividity after using standardised pressure on the areas (Kaatsch et al., 1994). Some bodies were stored at 12°C–15°C, but some had been stored at variable temperatures before measurements began at 10   hours after death and continued until 40   hours after death. This study resulted in over 20,000 values of brightness and colour difference values which were analysed with a computer programme. The baseline brightness of an area of lividity at various time intervals was measured, as well as the difference in brightness of the same area after standardised pressure was applied. It was confirmed that brightness decreased with the increase in PMI in an exponential fashion up to 40   hours after death. Kaatsch et al. (1994) noted that wide variations in their data could be attributed to factors such as skin colour, ante-mortem physical condition, cause of death and ante- and post-mortem environmental factors such as temperature and storage conditions prior to measurement.

The quantitative measurements of livor mortis are only useful up to about 30–40   hours post-mortem and before the changes of putrefaction have begun. They are complex, difficult to standardise and should not be used alone to estimate the post-mortem period (Swift, 2006).

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Anthropology/Odontology

T. Simmons , P.A. Cross , in Encyclopedia of Forensic Sciences (Second Edition), 2013

Late Postmortem Changes

Late postmortem changes are often referred to as those that become observable from 2 to 4   h postmortem.

Livor mortis, also known as lividity or hypostasis, is the gravitational pooling of blood to lower dependant areas resulting in a red/purple coloration. Although livor mortis is commonly seen between 2 and 4  h postmortem, its onset may begin in the 'early' period, as little as 30   min postmortem. In the early period of livor mortis, the coloration is not 'fixed' and pressure of the skin can cause 'blanching.' During this period, changing the position of the body can result in resettling of the blood in newly dependant areas. After a period of time, the blood coagulates and livor mortis becomes fixed. Rigor mortis is a reversible postmortem stiffening of the muscles, beginning in the muscles of the face and jaw, and extending to the rest of the body as the postmortem period progresses. The onset of rigor mortis is dependent upon temperature and the metabolic status of the deceased and occurs concomitantly with early stage autolysis. The timing of the onset of rigor mortis is variable, but it normally begins 2–6   h postmortem and has extended over the body by 12   h postmortem. Rigidity can last for 24–82   h after which gradual resolution occurs, progressing in the same order as rigor mortis commenced. Algor mortis is the cooling of body after death as it equilibrates with ambient temperature. Normal body temperature (rectal) can vary between individuals, ranging from 34.2 to 37.6   °C with a mean of 36.9   °C. Rectal temperature is similar in value to that of the brain, lungs, and abdominal organs and is often referred to as 'deep central temperature.'

A number of factors can influence body temperature at time of death, including emotional stress, pathological febrile conditions, metabolic disorders, circulatory disorders, and exposure to extreme environmental temperatures. Further factors influence the rate of cooling. These include body posture, body size, body fat, and presence of clothing.

Skin slippage occurs as a result of autolytic release of hydrolytic enzymes at the junction of the epidermis and dermis. This results in loosening and sloughing of the epidermis. This may be seen initially as the formation of vesicles or blisters. Fluid–filled vesicles known as 'bullae' can also form beneath the epidermis. Larger areas of skin may slough off and this can occur on any area of the body. Hair and nails will also be lost with the skin and where this occurs on the head, the whole scalp can slide off.

Color changes are indicative of putrefactive changes. They occur as a result of (1) the degradation of hemoglobin and (2) the formation of hydrogen sulfide (H2S) within vessels and tissues by enteric bacteria. Greening of the lower abdomen may occur within a few hours of death. The cecum, in particular, has a large population of enteric bacteria and will produce a large quantity of hydrogen sulfide. This will react with hemoglobin and other heme-containing proteins (e.g., myoglobin) and produce a green coloration in the lower abdomen, which becomes widespread throughout body tissues. The greening of superficial blood vessels can give the appearance of 'marbling,' sometimes called suggillation.

Bloating occurs as a result of putrefactive gases becoming trapped within the body. In addition to hydrogen sulfide, a wide range of other gases are produced during the putrefactive stage. The trapped gases cause distension of the abdomen, and in males, the trapped gases can be forced into the scrotum via the inguinal canals, causing distension of the scrotum and penis. As gases build up within tissues, bloating can also be observed in the tissues of the face and neck.

Putrefaction results in a complex mixture of volatile gases produced from the breakdown of carbohydrates and proteins. Two notable products are putrescine and cadaverine, both products of protein breakdown. These products have the characteristic decompositional odor and are utilized by cadaver dogs in the search for human remains.

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Estimation of the time since death in the early postmortem period (24–48 hours)

Roger W. Byard , in Estimation of the Time since Death, 2020

Livor mortis

Livor mortis or hypostasis refers to the red-blue-purple discolouration that develops in the skin of dependent parts of the body after death. Although the cause is believed to involve gravitational settling of blood within dermal capillaries, usually within 30  min to 3   h after death, the mechanism is obviously more complex as the pattern in a body that has not been moved is not that of a simple line with lividity below and pallor above, but is instead usually quite irregular with livid areas that are not infrequently quite high up on the body. For example, irregular pink patches which may be found on the cheeks have been attributed to the effects of local stasis and have been called Kirchhofrosen in German [14].

Early in the development of livor the colour is pink-red due to oxygenation of red blood cells (Fig. 2.2). This becomes darker over time as oxygen levels decline resulting in a more blue-purple hue [2]. The colour may, however, be influenced by a variety of factors such as carbon monoxide or cyanide poisoning, hypothermia, and in bodies stored at cold temperatures where the colour is light red-pink. Classically carbon monoxide toxicity is associated with a "cherry pink/red" discolouration because of the formation of carboxyhemoglobin [5]. Livor may be brown in colour in nitrate or nitrite poisoning due to the formation of methemoglobin and green with putrefactive changes due to the accumulation of sulfhemoglobin [2]. Livor may be markedly reduced or absent if there has been excessive blood loss prior to death or if the decedent was anaemic. It may also be very difficult to discern in individuals who are deeply sun-tanned or dark-skinned.

Fig. 2.2. Pink dependent lividity over the back of a recently deceased individual with prominent pressure blanching over the buttocks and centre of the back. Linear blanching can also be seen around the waist from clothing.

Livor becomes patterned when the body has had pressure applied to dependent areas which prevents dermal capillaries filling with blood. In Caucasians the compressed skin is pale and white which often contrasts dramatically with the surrounding red-purple congested skin, as can be seen on the back of the decedent in Fig. 2.2. If an object is pressed into the skin, it may leave a distinct outline as was observed on the outer thigh in Fig. 2.3 where the fingers have been resting.

Fig. 2.3. The original position of the fingers over the left side of the body can be seen due to pressure blanching.

One of the major uses of livor is in identifying the position that the decedent was left in after death, as livor would be expected over the back in someone who has died in the supine position, and over the front in someone who has died and remained in the prone position. Although the finding of anterior lividity with pressure blanching in a body found on its back indicates that the body has been moved after death, it is not uncommon to find posterior lividity in cases at autopsy who also have anterior lividity corresponding to a face down position after death. The reason for this is that most bodies develop posterior livor during the time that they are stored lying on their backs [15].

A related phenomenon which may be encountered in areas of lividity involves postmortem ecchymoses which are small areas of interstitial haemorrhage caused by rupture of subcutaneous capillaries and smaller vessels (predominantly veins) after death due to increased intravascular pressures from blood pooling [16].

While stages in the development of lividity have been used in the past to estimate the time since death the variability among individuals makes this a very inaccurate process [4]. An approximate guide to the chronology of these changes is of livor appearing between 30   min to 3   h as a patchy red discoloration which then becomes confluent, fully developing by four to 8   h, with the maximum intensity reached at approximately 10   h. The timing is summarized in Table 2.3 [7].

Table 2.3. Very approximate times for the appearance of livor mortis after death in cool to moderately warm environments [7].

Earliest Most common Latest
Patchy 0.5   h 2   h 3   h
Confluent 4   h 6   h 8   h
Maximum 6   h 10   h 16   h

Fixation is a term used to describe a failure of livor to blanch when pressure is applied to it because the position of the livor has become permanent. In the first 12–18   h after death livor is not fixed and so applied pressure will force blood out of engorged congested capillaries, rendering the area pale in light skinned individuals. This phenomenon is also seen when a body is moved, as the areas of livor will shift to the newly positioned dependent parts. It has been suggested that this occurs because the red blood cells in congested vessels are still intact and therefore are capable of shifting within the vascular system. After this time livor becomes fixed and so will not blanch under pressure or change if the body is moved. Fixation is thought to be due to haemoconcentration and then lysis of red blood cells producing an indelible stain in surrounding tissues, much as the lining of blood vessel becomes stained from putrefactive haemolysis [17]. The process is markedly affected by environmental temperatures with fixation occurring much earlier in warmer climates or situations.

Differentiating livor from bruising is important as the latter indicates that blunt force trauma has occurred. As noted above, in the early postmortem period livor will blanch with pressure, while bruises will not. A simple incision will clearly demonstrate normal appearing yellow subcutaneous fat in livor, contrasting with red interstitial haemorrhage in bruising [18].

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Materials and methods

Jarvis Hayman MB,ChB, FRCS(Ed), FRACS, MA(Hons) Archaeology, PhD , in Estimation of Time Since Death in Australian Conditions, 2021

3.2.4.1 Decomposition of the external body surface

Rigor mortis may still be present or just waning. The body is at ambient temperature. The skin is pallid. There is no bloating present. (1 point)

Rigor mortis is absent. Livor mortis is present except over pressure areas but is not fixed, as it blanches on pressure. The skin over the lower right abdomen is slightly green. Focal marbling and bloating are beginning. Fluid purging from mouth and rectum is beginning. (2 points)

Livor mortis is patchy or widespread and fixed. Green discolouration of the abdomen is becoming more widespread. Skin blistering is apparent and there may be some skin slippage, but it is not yet widespread. Abdominal and generalised bloating is at its maximum. Focal marbling and purging are now profuse. Facial features are obscured by bloating and a darkening colour. (3 points)

Livor mortis has been obscured by a more generalised green, purple or brown colour or a patchy mixture of all three. Bloating is still present but is receding. There is widespread skin slippage and peeling. Marbling is at its fullest extent and may still be visible. Drying of the peripheries is occurring, that is the fingers, toes, ears and nose. The orbits are sunken and the eyes soft, shrunken and the details obscured. The hair and fingernails are easily avulsed. (4 points)

The skin colour has darkened to a predominantly black colour and is widespread. Bloating has receded and the abdomen is now scaphoid. The skin is of a parchment texture and dry. There may be mummification of the digits. The hair and nails have become avulsed. There may be areas of mould or microbial growth and superficial patchy skin and tissue loss caused by insects. (5 points)

Much of the skin and soft tissue is lost. The internal organs may be exposed and either absent or shrivelled and dry. There may be mummification of residual tissue. Bones of the thoracic cage, limbs and pelvis may be exposed. The cranium may be disarticulated in the cervical region. (6 points)

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Forensic Medicine/Pathology

B. Madea , G. Kernbach-Wighton , in Encyclopedia of Forensic Sciences (Second Edition), 2013

Postmortem Lividity

After irreversible circulatory arrest, postmortem lividity develops as the earliest postmortem change. Following circulatory arrest, hydrostatic pressure becomes the leading force within the parallelogram of forces comprising blood pressure, structural barriers, tissue turgor, and pressure from underlying surfaces. Hypostasis means the movement of body fluids according to gravity. All compartments are involved in hypostasis, not only intravascular but transcellular fluids as well. Influenced by gravity, blood moves to the lowest parts within the vascular system; in a supine position, it flows to the back, buttocks, thighs, calves, and back of the neck. Irregular facial pink patches, especially over the cheeks in the agonal period, are caused by local stasis. Postmortem cutaneous lividity is a consequence of movement of blood into capillaries of the corium. It may appear 20–30   min postmortem, still as pink patches in the early stages becoming gradually confluent with increasing postmortem time. Due to consumption of oxygen, the color changes from pink to dark pink or bluish.

In areas of intense hypostasis, cutaneous petechial hemorrhages due to capillary ruptures, called vibices, may develop. It is not only the development of lividity or of color that is of diagnostic and criminalistic relevance, but also its distribution, as well as the phenomena of fixation (disappearance after turning the body) and disappearance (blanching) on blunt/thumb pressure.

In case of carbon monoxide poisoning and cyanide toxicity, the color of hypostasis is typically cherry pinkish, while methemoglobin intoxication is brownish. Due to lack of dissociation of oxygen from hemoglobin, a bright pink color may be seen in hypothermia as well. In a body transferred from a cold environment into normal room temperature, typical zonal segmentation of hypostasis may be seen with a dark bluish color in the rewarmed areas.

Of predominant criminalistic significance are the phenomena of dissappearance on pressure and disappearance of lividity after turning the body. In the early stages, lividity will completely disappear on soft thumb pressure, but with ongoing postmortem interval, the pressure also has to increase. Later, lividity will disappear only incompletely on pressure and finally it will not disappear at all.

If the body is turned in the early postmortem interval, some or all of the hypostasis may move to different areas. In a comparatively later postmortem interval, only some of the hypostasis will migrate down to new areas and only slight blanching will be noted in the original region.

With increasing postmortem time, disappearance of lividity on thumb pressure and relocation after shifting decreases, and then ceases completely.

The best statistical data available for the different criteria of lividity were summarized by Mallach, who calculated mean values, standard deviations, and 95% limits of confidence based on textbook reports ( Table 1 ). As better data are still missing, these data are still undisputed. However, it should be kept in mind that these data do not represent absolute thresholds. Investigations based on quantitative measurements of livor mortis have not yet gained practical importance.

Table 1. Time course of different criteria of lividity. Statistical calculations by Mallach based on textbook reports. The statistical calculations are not based on cross-sectional or longitudinal studies but on empiric knowledge quoted in textbooks. x ¯ = mean value ; s  =   standard deviation

x ¯ s 2s Range of scatter
Lower limit Upper limit Lower limit Upper limit Number of quotations
Development ¾ 1/2 – 2 1/4 3 17
Confluence 2(1/2) 1 3/4 4(1/4) 1 4 5
Greatest distension and intensity 9(1/2) 4(1/2) 1/2 18(1/4) 3 16 7
Displacement
1. Complete on thumb pressure 5(1/2) 6 – 17(1/2) 1 20 5
2. Incomplete on sharp pressure (forceps) 17 10(1/2) – 37(1/2) 10 36 4
Displacement after turning the body
1. Complete 3(3/4) 1 2 5(1/2) 2 6 11
2. Incomplete 11 4(1/2) 2(1/4) 20 4 24 11
3. Only little pallor 18(1/2) 8 2(1/2) 34(1/2) 10 30 7

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