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Necropsy findings in fatal hypothermia cases
Forensic Science, 8 (1976) 155 - 164 0 Elsevier Sequoia S.A., Lausanne -Printed
NECROPSY
JORMA
FINDINGS
IN FATAL
155 in the Netherlands
HYPOTHERMIA
CASES
HIRVONEN
Department (Received
of Forensic Medicine, December
University
8, 1975; accepted
of Oulu, 90220
Oulu 22 (Finland)
June 9, 1976)
SUMMARY A series of 22 cases of fatal accidental or suicidal hypothermia is presented. Necropsy findings on which the diagnosis can be based were analysed. Purple skin and swelling of face, hands and feet, as well as violet patches on elbows or knees were the most frequent external signs (frequency 54-59s). erosions or The most conspicuous internal macroscopic signs were gastric haemorrhages, which were seen in half of the cases. Other less frequent signs were pulmonary oedema and acute renal and hepatic degeneration. Microscopically the myocardium showed small degenerative foci and/or fuchsinophilic fibres in two thirds of the cases. The myocardium was macroscopically normal. Histamine and serotonin assays from urine did not indicate increased excretion during exposure. Catecholamine concentrations in urine were high (> 0.1 pg/ml) in most hypothermia deaths indicating increased excretion due to cold. The best diagnostic signs seem to be purple skin and oedema in face and ears, stomach erosions, degenerative foci in myocardium and high concentration of catecholamines in the urine.
INTRODUCTION
In fatalities due to hypothermia the necropsy findings even at their best can be scarce. There are cases where no morphological signs are noticed and the diagnosis must be based solely on circumstantial evidence. Textbooks of forensic sciences and other sources report cadaveric signs such as red livores, purple patches on extremities, red blood, Wichnevski erosions in the stomach, pancreatic haemorrhage, lipid depletion from the adrenal cortex and even vacuolisation of the liver cells and other similar minute signs of hypoxia [ 11. Cases of fatal hypothermia are usually accidents, but suicides by freezing are also committed during the long and rather harsh winter of northern Finland. The victims are usually found in unknown circumstances in forests and fields without any information. Therefore it is necessary to search for reliable signs and tests upon which the diagnosis of death due to hypothermia could be based. It’ is known from the clinical use of hypothermia and animal experiments, that cold does not easily cause changes in the tissues. From the forensic point of view it would be important to be able to demonstrate changes in the
156
body, which show that the organism has reacted to cold. A further goal would be to find changes which could differentiate death due to hypothermia from other types of deaths due to exhaustion of adaptative mechanisms. The mechanism of death in hypothermia is cessation of heart function which in large mammals such as dog and man appears as atria1 and ventricular fibrillation. The myocardium of hypothermic dogs shows small foci of coagulation necrosis [2]. These findings led to the search for similar changes in the myocardium of human victims of fatal hypothermia. Accumulation of neutral fats in the liver, kidneys and heart was not seen in the first cases of our series and was not investigated further. Because the morphological findings in fatal hypothermia are so scarce, biochemical parameters were scrutinised. Post-mortem assays of blood glucose and free fatty acids gave variable results and were regarded as unpromising leads. Increase of catecholamine [ 31, histamine and serotonin [ 41 excretion into urine in cold conditions has been demonstrated. The concentration of total catecholamines was found to be high in the urine of some victims of fatal hypothermia. Thus, the concentration of catecholamines, histamine, and serotonin in urine was measured. The paucity of findings in deaths due to hypothermia compelled us to use different tests in the first phase of investigation in order to find some useful ones. The present report deals with what has been found and what are some general features of hypothermia death in rather cold conditions. MATERIAL
The material of 18 males and 4 females included all necropsy cases from the period of 1971-1975 where hypothermia was determined as the principal cause, or the contributing cause of death. Cases from the earlier years were not included because of incomplete investigations. The mean age of the males was 41 years (range 15-65) and that of the females 52 (range 20-89). The cases occurred mostly from October to February: only one man died of hypothermia in May. This distribution reflects the coldest time of the year, but it was unexpected that as many cases occurred in October as in February. This observation probably indicates a certain lack of cold-acclimation after the summer months. Seventeen cases suffered from dry exposure (i.e. cold air), 5 cases suffered from exposure either in cold water or they had wetted their clothes and were thereafter exposed to cold air. Temperature of the air during exposure had been from +5 ’ to -30 “C. The ambient temperature in the wet exposures had been from +lO ’ to ?O “C. Estimated duration of the exposure ranged from approximately 1.5 hours at -30 “C to 12 hours at +5 “C. In the majority the duration was 3-6 hours and the corresponding ambient temperature approximately -10 “C. More exact calculations on the dependence of the duration of exposure as a function of the ambient temperature was not possible because of the lack of accurate information about the nature of exposure.
157 METHODS
The histological methods were selected according to the results obtained by Sarajas [Z] using the hearts of hypothermic dogs. In addition to the routine haematoxylin-eosin, Heidenhain’s iron haematoxylin (HIH) [5], McManus PAS and Mallory’s phosphotungstic acid haematoxylin (PTAH) [ 61 and acid fuchsin [ 71 were applied to the formalin fixed sample. In some cases, enzymehistochemical fl-hydroxy-butyrate, succinic and malate dehydrogenase methods were tried [8]. The enzyme methods did not give as distinct and reliable information as compared with the other stainings and therefore they were not applied through the whole material. Assays of the biogenic amines in the urine Histamine: The fluorometric method of Anton and Sayre [9] was used, omitting the chloroform purification step. Serotonin: The method of Curzon and Greene [lo] was adopted in principle. The amine was extracted at pH 10 into butanol and finally condensed with orthophthalaldehyde and measured in Aminco-Bowman fluorometer (360 nm as excitation, and 470 nm as emission wave-lengths). Catecholamines: Total catecholamine concentration was measured with the modified fluorometric method of Anton and Sayre [ 111. Blood alcoho2 concentration was measured gas-chromatographically and with ADH enzymatic-spectrophotometric method. Presence of glucose in urine was checked with Tes-tape. Drug analysis was performed only if they were suspected to be involved. The identification was done in the Laboratory of Forensic Chemistry, Department of Forensic Medicine in Helsinki University, using routine methods. FINDINGS
External signs The frequencies of the various signs in the present material are given in Table I. Red skin, frostbites in naked parts and violet patches (Fig. 1) on extremities were seen in more than half of the cases. Dilatation of veins in the skin was less frequent. In addition to the patches, excoriations were occasionally present on the extremities, these being usually bright red. If the colouration of the skin is marked, as it can be in deep frost when alcohol has been taken, the cadaver can resemble that resulting from CO-poisoning. Znterizalsigns Mucosal conspicious
erosions or haemorrhages and frequent macroscopical
in the stomach were the most sign. Other signs such as acute
158 TABLE I External findings in hypothermia deaths Sign
Frequency
Red or purple skin Swelling of ears, hands or other frostbites Violet patches on knees or elbows Dilated veins on extremities
59% 59% 54% 41%
(13/22) (13/22) (12/22) ( 9/22)
Fig. 1. Violet patches on the elbow and dilated veins on the antebrachium.
pulmonary oedema and pancreatic hepatic and renal degeneration, haemorrhages were less often observed (Table II). Histological investigation was most revealing in the myocardium which macroscopically appeared quite normal. Under close examination small foci were seen in the myocardium. The foci consisted of broken or curly homogeneous fibres, exudation and occasional extravasation of red cells (Fig. 2). The foci could be better observed with special stainings. In HIH staining, the foci were black and in addition dark solitary fibres or parts of fibres were
159
TABLE II Internal signs in hypothermia deaths Sign Macroscopical Stomach erosions or haemorrhages Acute nephrosis Pulmonary oedema Hepatic degeneration Pancreatic haemorrhages Microscopical Myocardial degenerative foci
Frequency
45% (10/22) 32% ( 7122) 27% ( 6/22) 23% ( 5/22) lS%( 4/22) 68% (15/22)
Fig. 2. A degenerative focus in the myocardium breaking of myofibres. x 260, H-E.
of a hypothermic
victim. Curling and
observed. In a few instances, the foci were PAS-positive. In PTAH staining the focus appeared dark violet against a purple background (Fig. 3). Acid fuchsin staining showed solitary red fibres but no foci (Fig. 4). The dehydrogenase reactions looked quite strong and even. Only occasionally negative or poorly stained spots were seen. Control sections were taken from victims of rapid violent deaths such as suicides by hanging or shooting. In these cases there were no myocardial changes. As further controls some hearts, which were acutely degenerated as
161
TABLE
III
Biogenic
amines
in urine, pg of the amine in 1 ml of urine:
Mean + SD Control
Amine
Hypothermia
Catecholamines (adrenaline + noradrenaline)
0.20 r 0.16 (N=9)
Histamine
0.15 + 0.17 (N = 10)
0.21 + 0.10 (N = 6)
Serotonin
0.13 f 0.10 (N = 10)
0.15 * 0.02 (N=6)
(p 0.05-0.1)
0.08 f 0.07 (N=6)
a consequence of shock were stained by the same methods. These sections showed no fuchsinophilia and were also negative in HIH and PTAH stainings. Otherwise the histological findings were non-specific such as oedema in brain and lungs. The mucosal erosions showed haemorrhage, oedema and loosening of the epithelia. Biochemical findings Test for urinary glucose was positive in some cases. This can be used as an easy and rapid test for hyperglycaemia which occurs in the early phase of cold exposure. Of course, the possibility of diabetes should also be considered. The concentration of catecholamines (adrenaline and noradrenaline together) tended to be high in the hypothermia cases (Table III). The highest catecholamine concentrations were observed in 2 cases, which had extensive exposure without alcohol; one of these was a suicide. Low concentrations were assayed in the cases which had high blood alcohol concentration. The difference between the means of the hypothermia group and the controls was almost significant (p between 0.05 and 0.1). was slightly lower in the hypoThe mean of histamine concentration thermia than in the control group. The difference was not significant and is possibly due to the general dilution of urine because of cold diuresis. The serotonin values did not differ significantly in either. Alcohol was detected in 12 cases. The blood concentration was 1.25 2.49 per ml (the mean 1.50 per ml). Drugs were involved in 4 cases. Two victims had taken barbiturates and 2 phenothiazines. Both drugs are often reported to have contributed to incidents of hypothermia.
DISCUSSION
The survey of external whole confirmed earlier
signs in our series of hypothermia cases on the reports. The most frequent signs were reddish
162
livores, purple colour and swelling of ears, face, hands and feet (frostbites), and violet patches on knees and elbows. Reddish livores is not a vital sign of hypothermia, but violet livores can turn red if the body is stored for longer time (several days) in a cold chamber. This is said to be due to the increased binding of Oa to haemoglobin in the cold [12]. The purple colour of the skin and the vein figures in the extremities can also develope supravitally. The violet patches on knees and elbows are small hyperaemic areas, which have probably developed in the final phase prior to death when the skin is pressed against snow or cold ground. The swelling of the exposed parts is more clearly a vital sign than the colouration of the skin. In cold injury capillaries are damaged which causes leaking of plasma into the tissue [ 131. The development of oedema in injuries demands active circulation. Therefore the swollen ears and nose can be regarded as vital frostbites. The internal necropsy findings were few and irregular or even absent. Erosions or haemorrhages in the stomach mucosa, i.e. Wichnevski ulcerations, were seen in approximately half of the cases. The literature reports give a frequency varying from O-90%. The formation of ulcers may depend on the duration of exposure, individual reaction to stress and resistance of the gastric mucosa. Experiments with rats indicate that tissue amines, histamine and serotonin, are in some way involved in the ulcer formation [14,15]. Other signs of systemic stress were less frequent. Pancreatic lesions have been frequent in some English series of necropsies [16, 171, but they were rare in the present material. The discrepancy may be explained by the differences in the material. The victims of the English series have generally been older people and the exposure mild but longlasting, l-2 days in cool rooms [ 181. In the present series, the victims were younger and exposure colder, leaving a shorter time for development of the pancreatic lesions. The histochemical investigation of the myocardium led to some interesting and seemingly useful findings. The small foci of degeneration seen in myocardium which macroscopically appeared quite normal were similar to those found in hypothermic dogs [2]. The foci were better demonstrated with stainings specially recommended for muscle. Phosphotungstic acid haematoxylin and iron haematoxylin stained the foci darker than the rest of the myocardium. The alteration of the single myocardial cells was further seen as fuchsinophilia. These kinds of changes in the myocardium seem to be typical of large mammals. For instance, our experiments with guinea-pigs have not revealed similar changes. The foci can be comparable to the lesions seen in the myocardium of rats after noradrenaline injections [ 191, because cold stress is a powerful releaser of catecholamines, especially noradrenaline. Accumulation of fat in the myocardium, kidneys and liver, as reported occurring in hypothermia victims [17, 181, can be seen in the normal ‘myocardium of older people [20]. Therefore this finding cannot be taken as a reliable sign for exposure to cold.
163
The assays of the concentrations of biogenic amines in urine yielded variable results. In the present cases, histamine and serotonin concentrations tended to be lower in the hypothermia victims than in the controls. Measuring the concentration is not the best way to check increased excretion, but it is the only way in the study of cadavers. At present it seems that histamine and serotonin assays cannot be regarded as tests for hypothermia deaths. Measurements of the urinary catecholamine contents were more promising than those of histamine and serotonin. The concentration was on the average higher in the hypothermia group, but because of great variation the statistical significance remained below the 95% level. The trend towards increased values in urinary catecholamines agrees well with the findings in cold exposed males [13] and is thus worthy of further studies. It is worth pointing out the possible source error in this test, resulting from the dilution of urine by cold diuresis. However, the author is apt to recommend the catecholamine test as a means to show that the organism has reacted to cold stress. The statement that there is no single sign of hypothermia death in necropsy [21] is perhaps still valid, but the combined macroscopic, microscopic and biochemical changes in cadaver, justify the diagnosis with reasonable certainty. REFERENCES 1 J. Hirvonen, Local and systemic effects of accidental hypothermia, In Forensic Medicine, Study of Trauma and Environmental Hazards, Ed., C. G. Tedeschi, Pergamon, New York, 1975. 2 H. S. S. Sarajas, Heart damage in dogs subjected to hypothermia, with or without complicating cardiac operation, Ann. Acad. Sci. Fenn. Ser. A, 86 (1961) l-230. 3 L. B. Lamke, S. Lennquist, S-O. Liljedahl and B. Wedin, The influence of cold stress on catecholamine excretion and oxygen uptake of normal persons, Stand. J. Clin. Lab. Invest., 30 (1972) 57-68. 4 J. LeBlanc, Secretion and activity of histamine, and serotonin during cold adaptation, Am. J. Physiol., 204 (1963) 520-523. 5 B. Romeis, Mikroskopische Technik, Oldenburg, Munich, 1968. 6 Manual and Histologic Staining Methods of the Armed Forces Institute of Pathology, 3rd edn., Eds., L. G. Luna, MC Graw-Hill, New York, 1968. 7 R. W. Poley, C. D. Fobes and M. J. Hall, Fuchsinophilia in early myocardial infarction, Arch. Pathol., 77 (1964) 325-329. 8 T. Barka and P. J. Anderson, Histochemistry, Harper and Row, New York, 1965. 9 A. H. Anton and D. F. Sayre, A modified fluorometric procedure for tissue histamine and its distribution in various mammals, J. Pharmacol. Exp. Ther., 166 (1969) 285 292. 10 G. Curzon and A. R. Green, Rapid method for the determination of 5-hydroxytryptamine and 5-hydroxy-indole acetic acid in small regions of rats brain, Br. J. Pharmacol., 39 (1970) 653-655. 11 A. H. Anton and D. F. Sayre, A study of the factors affecting the aluminum oxide-trihydroxy indole procedure for the analysis of catecholamines, J. Pharmacol. Exp. Ther., 138 (1962) 360-37 5. 12 H. Killian, Der Kg’lteunfall. Allgemeine Unterkiihlung, Dustri-Verlag, Munich, 1966.
164 13 J. P. Kulka, Cold injury of the skin. The pathogenic role of microcirculatory impairment, Arch. Environ. Health, 11 (1965) 484-497. 14 R. J. Lavine and E. C. Senay, Histamine in the pathogenesis of stress ulcers in the rat, Am. J. Physiol., 214 (1968) 892-896. 15 J. Hirvonen and R. Elfving, Histamine and serotonin in the gastric erosions of rats dead from exposure to cold. A Histochemical and Quantitative Study, Z. Rechtsmed., 74 (1974) 273-281. 16 A. K. Mant, Some post-mortem observations in accidental hypothermia, Med. Sci. Law, 4 (1964) 44-46. 17 A. K. Mant, Autopsy diagnosis of accidental hypothermia, J. Forensic Med., 16 (1969) 126-129. 18 H. Duguid, R. G. Simpson and J. M. Stowers, Accidental hypothermia, Lancet, 2 (1961) 1213--1219. 19 U. Kreinsen und C. M. Busing, Experimentelle Herzmuskelnekrosen bei der Ratte nach Gabe von 1-Noradrenaline und Strophantin, Virchows Arch. A, 367 (1975) 4757. 20 M. Alavaikko, J. Hirvonen and 0. R&&en, Fatty change in papillary heart muscle and in its arterioles, Acta Pathol. &and., 78 (1970) 458-472. 21 E. Trube-Becker, Zur Begutachtung beim Tod durch Unterkiihlung, Z. Rechtsmed., 59 (1967) 211-227.
NECROPSY
JORMA
FINDINGS
IN FATAL
155 in the Netherlands
HYPOTHERMIA
CASES
HIRVONEN
Department (Received
of Forensic Medicine, December
University
8, 1975; accepted
of Oulu, 90220
Oulu 22 (Finland)
June 9, 1976)
SUMMARY A series of 22 cases of fatal accidental or suicidal hypothermia is presented. Necropsy findings on which the diagnosis can be based were analysed. Purple skin and swelling of face, hands and feet, as well as violet patches on elbows or knees were the most frequent external signs (frequency 54-59s). erosions or The most conspicuous internal macroscopic signs were gastric haemorrhages, which were seen in half of the cases. Other less frequent signs were pulmonary oedema and acute renal and hepatic degeneration. Microscopically the myocardium showed small degenerative foci and/or fuchsinophilic fibres in two thirds of the cases. The myocardium was macroscopically normal. Histamine and serotonin assays from urine did not indicate increased excretion during exposure. Catecholamine concentrations in urine were high (> 0.1 pg/ml) in most hypothermia deaths indicating increased excretion due to cold. The best diagnostic signs seem to be purple skin and oedema in face and ears, stomach erosions, degenerative foci in myocardium and high concentration of catecholamines in the urine.
INTRODUCTION
In fatalities due to hypothermia the necropsy findings even at their best can be scarce. There are cases where no morphological signs are noticed and the diagnosis must be based solely on circumstantial evidence. Textbooks of forensic sciences and other sources report cadaveric signs such as red livores, purple patches on extremities, red blood, Wichnevski erosions in the stomach, pancreatic haemorrhage, lipid depletion from the adrenal cortex and even vacuolisation of the liver cells and other similar minute signs of hypoxia [ 11. Cases of fatal hypothermia are usually accidents, but suicides by freezing are also committed during the long and rather harsh winter of northern Finland. The victims are usually found in unknown circumstances in forests and fields without any information. Therefore it is necessary to search for reliable signs and tests upon which the diagnosis of death due to hypothermia could be based. It’ is known from the clinical use of hypothermia and animal experiments, that cold does not easily cause changes in the tissues. From the forensic point of view it would be important to be able to demonstrate changes in the
156
body, which show that the organism has reacted to cold. A further goal would be to find changes which could differentiate death due to hypothermia from other types of deaths due to exhaustion of adaptative mechanisms. The mechanism of death in hypothermia is cessation of heart function which in large mammals such as dog and man appears as atria1 and ventricular fibrillation. The myocardium of hypothermic dogs shows small foci of coagulation necrosis [2]. These findings led to the search for similar changes in the myocardium of human victims of fatal hypothermia. Accumulation of neutral fats in the liver, kidneys and heart was not seen in the first cases of our series and was not investigated further. Because the morphological findings in fatal hypothermia are so scarce, biochemical parameters were scrutinised. Post-mortem assays of blood glucose and free fatty acids gave variable results and were regarded as unpromising leads. Increase of catecholamine [ 31, histamine and serotonin [ 41 excretion into urine in cold conditions has been demonstrated. The concentration of total catecholamines was found to be high in the urine of some victims of fatal hypothermia. Thus, the concentration of catecholamines, histamine, and serotonin in urine was measured. The paucity of findings in deaths due to hypothermia compelled us to use different tests in the first phase of investigation in order to find some useful ones. The present report deals with what has been found and what are some general features of hypothermia death in rather cold conditions. MATERIAL
The material of 18 males and 4 females included all necropsy cases from the period of 1971-1975 where hypothermia was determined as the principal cause, or the contributing cause of death. Cases from the earlier years were not included because of incomplete investigations. The mean age of the males was 41 years (range 15-65) and that of the females 52 (range 20-89). The cases occurred mostly from October to February: only one man died of hypothermia in May. This distribution reflects the coldest time of the year, but it was unexpected that as many cases occurred in October as in February. This observation probably indicates a certain lack of cold-acclimation after the summer months. Seventeen cases suffered from dry exposure (i.e. cold air), 5 cases suffered from exposure either in cold water or they had wetted their clothes and were thereafter exposed to cold air. Temperature of the air during exposure had been from +5 ’ to -30 “C. The ambient temperature in the wet exposures had been from +lO ’ to ?O “C. Estimated duration of the exposure ranged from approximately 1.5 hours at -30 “C to 12 hours at +5 “C. In the majority the duration was 3-6 hours and the corresponding ambient temperature approximately -10 “C. More exact calculations on the dependence of the duration of exposure as a function of the ambient temperature was not possible because of the lack of accurate information about the nature of exposure.
157 METHODS
The histological methods were selected according to the results obtained by Sarajas [Z] using the hearts of hypothermic dogs. In addition to the routine haematoxylin-eosin, Heidenhain’s iron haematoxylin (HIH) [5], McManus PAS and Mallory’s phosphotungstic acid haematoxylin (PTAH) [ 61 and acid fuchsin [ 71 were applied to the formalin fixed sample. In some cases, enzymehistochemical fl-hydroxy-butyrate, succinic and malate dehydrogenase methods were tried [8]. The enzyme methods did not give as distinct and reliable information as compared with the other stainings and therefore they were not applied through the whole material. Assays of the biogenic amines in the urine Histamine: The fluorometric method of Anton and Sayre [9] was used, omitting the chloroform purification step. Serotonin: The method of Curzon and Greene [lo] was adopted in principle. The amine was extracted at pH 10 into butanol and finally condensed with orthophthalaldehyde and measured in Aminco-Bowman fluorometer (360 nm as excitation, and 470 nm as emission wave-lengths). Catecholamines: Total catecholamine concentration was measured with the modified fluorometric method of Anton and Sayre [ 111. Blood alcoho2 concentration was measured gas-chromatographically and with ADH enzymatic-spectrophotometric method. Presence of glucose in urine was checked with Tes-tape. Drug analysis was performed only if they were suspected to be involved. The identification was done in the Laboratory of Forensic Chemistry, Department of Forensic Medicine in Helsinki University, using routine methods. FINDINGS
External signs The frequencies of the various signs in the present material are given in Table I. Red skin, frostbites in naked parts and violet patches (Fig. 1) on extremities were seen in more than half of the cases. Dilatation of veins in the skin was less frequent. In addition to the patches, excoriations were occasionally present on the extremities, these being usually bright red. If the colouration of the skin is marked, as it can be in deep frost when alcohol has been taken, the cadaver can resemble that resulting from CO-poisoning. Znterizalsigns Mucosal conspicious
erosions or haemorrhages and frequent macroscopical
in the stomach were the most sign. Other signs such as acute
158 TABLE I External findings in hypothermia deaths Sign
Frequency
Red or purple skin Swelling of ears, hands or other frostbites Violet patches on knees or elbows Dilated veins on extremities
59% 59% 54% 41%
(13/22) (13/22) (12/22) ( 9/22)
Fig. 1. Violet patches on the elbow and dilated veins on the antebrachium.
pulmonary oedema and pancreatic hepatic and renal degeneration, haemorrhages were less often observed (Table II). Histological investigation was most revealing in the myocardium which macroscopically appeared quite normal. Under close examination small foci were seen in the myocardium. The foci consisted of broken or curly homogeneous fibres, exudation and occasional extravasation of red cells (Fig. 2). The foci could be better observed with special stainings. In HIH staining, the foci were black and in addition dark solitary fibres or parts of fibres were
159
TABLE II Internal signs in hypothermia deaths Sign Macroscopical Stomach erosions or haemorrhages Acute nephrosis Pulmonary oedema Hepatic degeneration Pancreatic haemorrhages Microscopical Myocardial degenerative foci
Frequency
45% (10/22) 32% ( 7122) 27% ( 6/22) 23% ( 5/22) lS%( 4/22) 68% (15/22)
Fig. 2. A degenerative focus in the myocardium breaking of myofibres. x 260, H-E.
of a hypothermic
victim. Curling and
observed. In a few instances, the foci were PAS-positive. In PTAH staining the focus appeared dark violet against a purple background (Fig. 3). Acid fuchsin staining showed solitary red fibres but no foci (Fig. 4). The dehydrogenase reactions looked quite strong and even. Only occasionally negative or poorly stained spots were seen. Control sections were taken from victims of rapid violent deaths such as suicides by hanging or shooting. In these cases there were no myocardial changes. As further controls some hearts, which were acutely degenerated as
161
TABLE
III
Biogenic
amines
in urine, pg of the amine in 1 ml of urine:
Mean + SD Control
Amine
Hypothermia
Catecholamines (adrenaline + noradrenaline)
0.20 r 0.16 (N=9)
Histamine
0.15 + 0.17 (N = 10)
0.21 + 0.10 (N = 6)
Serotonin
0.13 f 0.10 (N = 10)
0.15 * 0.02 (N=6)
(p 0.05-0.1)
0.08 f 0.07 (N=6)
a consequence of shock were stained by the same methods. These sections showed no fuchsinophilia and were also negative in HIH and PTAH stainings. Otherwise the histological findings were non-specific such as oedema in brain and lungs. The mucosal erosions showed haemorrhage, oedema and loosening of the epithelia. Biochemical findings Test for urinary glucose was positive in some cases. This can be used as an easy and rapid test for hyperglycaemia which occurs in the early phase of cold exposure. Of course, the possibility of diabetes should also be considered. The concentration of catecholamines (adrenaline and noradrenaline together) tended to be high in the hypothermia cases (Table III). The highest catecholamine concentrations were observed in 2 cases, which had extensive exposure without alcohol; one of these was a suicide. Low concentrations were assayed in the cases which had high blood alcohol concentration. The difference between the means of the hypothermia group and the controls was almost significant (p between 0.05 and 0.1). was slightly lower in the hypoThe mean of histamine concentration thermia than in the control group. The difference was not significant and is possibly due to the general dilution of urine because of cold diuresis. The serotonin values did not differ significantly in either. Alcohol was detected in 12 cases. The blood concentration was 1.25 2.49 per ml (the mean 1.50 per ml). Drugs were involved in 4 cases. Two victims had taken barbiturates and 2 phenothiazines. Both drugs are often reported to have contributed to incidents of hypothermia.
DISCUSSION
The survey of external whole confirmed earlier
signs in our series of hypothermia cases on the reports. The most frequent signs were reddish
162
livores, purple colour and swelling of ears, face, hands and feet (frostbites), and violet patches on knees and elbows. Reddish livores is not a vital sign of hypothermia, but violet livores can turn red if the body is stored for longer time (several days) in a cold chamber. This is said to be due to the increased binding of Oa to haemoglobin in the cold [12]. The purple colour of the skin and the vein figures in the extremities can also develope supravitally. The violet patches on knees and elbows are small hyperaemic areas, which have probably developed in the final phase prior to death when the skin is pressed against snow or cold ground. The swelling of the exposed parts is more clearly a vital sign than the colouration of the skin. In cold injury capillaries are damaged which causes leaking of plasma into the tissue [ 131. The development of oedema in injuries demands active circulation. Therefore the swollen ears and nose can be regarded as vital frostbites. The internal necropsy findings were few and irregular or even absent. Erosions or haemorrhages in the stomach mucosa, i.e. Wichnevski ulcerations, were seen in approximately half of the cases. The literature reports give a frequency varying from O-90%. The formation of ulcers may depend on the duration of exposure, individual reaction to stress and resistance of the gastric mucosa. Experiments with rats indicate that tissue amines, histamine and serotonin, are in some way involved in the ulcer formation [14,15]. Other signs of systemic stress were less frequent. Pancreatic lesions have been frequent in some English series of necropsies [16, 171, but they were rare in the present material. The discrepancy may be explained by the differences in the material. The victims of the English series have generally been older people and the exposure mild but longlasting, l-2 days in cool rooms [ 181. In the present series, the victims were younger and exposure colder, leaving a shorter time for development of the pancreatic lesions. The histochemical investigation of the myocardium led to some interesting and seemingly useful findings. The small foci of degeneration seen in myocardium which macroscopically appeared quite normal were similar to those found in hypothermic dogs [2]. The foci were better demonstrated with stainings specially recommended for muscle. Phosphotungstic acid haematoxylin and iron haematoxylin stained the foci darker than the rest of the myocardium. The alteration of the single myocardial cells was further seen as fuchsinophilia. These kinds of changes in the myocardium seem to be typical of large mammals. For instance, our experiments with guinea-pigs have not revealed similar changes. The foci can be comparable to the lesions seen in the myocardium of rats after noradrenaline injections [ 191, because cold stress is a powerful releaser of catecholamines, especially noradrenaline. Accumulation of fat in the myocardium, kidneys and liver, as reported occurring in hypothermia victims [17, 181, can be seen in the normal ‘myocardium of older people [20]. Therefore this finding cannot be taken as a reliable sign for exposure to cold.
163
The assays of the concentrations of biogenic amines in urine yielded variable results. In the present cases, histamine and serotonin concentrations tended to be lower in the hypothermia victims than in the controls. Measuring the concentration is not the best way to check increased excretion, but it is the only way in the study of cadavers. At present it seems that histamine and serotonin assays cannot be regarded as tests for hypothermia deaths. Measurements of the urinary catecholamine contents were more promising than those of histamine and serotonin. The concentration was on the average higher in the hypothermia group, but because of great variation the statistical significance remained below the 95% level. The trend towards increased values in urinary catecholamines agrees well with the findings in cold exposed males [13] and is thus worthy of further studies. It is worth pointing out the possible source error in this test, resulting from the dilution of urine by cold diuresis. However, the author is apt to recommend the catecholamine test as a means to show that the organism has reacted to cold stress. The statement that there is no single sign of hypothermia death in necropsy [21] is perhaps still valid, but the combined macroscopic, microscopic and biochemical changes in cadaver, justify the diagnosis with reasonable certainty. REFERENCES 1 J. Hirvonen, Local and systemic effects of accidental hypothermia, In Forensic Medicine, Study of Trauma and Environmental Hazards, Ed., C. G. Tedeschi, Pergamon, New York, 1975. 2 H. S. S. Sarajas, Heart damage in dogs subjected to hypothermia, with or without complicating cardiac operation, Ann. Acad. Sci. Fenn. Ser. A, 86 (1961) l-230. 3 L. B. Lamke, S. Lennquist, S-O. Liljedahl and B. Wedin, The influence of cold stress on catecholamine excretion and oxygen uptake of normal persons, Stand. J. Clin. Lab. Invest., 30 (1972) 57-68. 4 J. LeBlanc, Secretion and activity of histamine, and serotonin during cold adaptation, Am. J. Physiol., 204 (1963) 520-523. 5 B. Romeis, Mikroskopische Technik, Oldenburg, Munich, 1968. 6 Manual and Histologic Staining Methods of the Armed Forces Institute of Pathology, 3rd edn., Eds., L. G. Luna, MC Graw-Hill, New York, 1968. 7 R. W. Poley, C. D. Fobes and M. J. Hall, Fuchsinophilia in early myocardial infarction, Arch. Pathol., 77 (1964) 325-329. 8 T. Barka and P. J. Anderson, Histochemistry, Harper and Row, New York, 1965. 9 A. H. Anton and D. F. Sayre, A modified fluorometric procedure for tissue histamine and its distribution in various mammals, J. Pharmacol. Exp. Ther., 166 (1969) 285 292. 10 G. Curzon and A. R. Green, Rapid method for the determination of 5-hydroxytryptamine and 5-hydroxy-indole acetic acid in small regions of rats brain, Br. J. Pharmacol., 39 (1970) 653-655. 11 A. H. Anton and D. F. Sayre, A study of the factors affecting the aluminum oxide-trihydroxy indole procedure for the analysis of catecholamines, J. Pharmacol. Exp. Ther., 138 (1962) 360-37 5. 12 H. Killian, Der Kg’lteunfall. Allgemeine Unterkiihlung, Dustri-Verlag, Munich, 1966.
164 13 J. P. Kulka, Cold injury of the skin. The pathogenic role of microcirculatory impairment, Arch. Environ. Health, 11 (1965) 484-497. 14 R. J. Lavine and E. C. Senay, Histamine in the pathogenesis of stress ulcers in the rat, Am. J. Physiol., 214 (1968) 892-896. 15 J. Hirvonen and R. Elfving, Histamine and serotonin in the gastric erosions of rats dead from exposure to cold. A Histochemical and Quantitative Study, Z. Rechtsmed., 74 (1974) 273-281. 16 A. K. Mant, Some post-mortem observations in accidental hypothermia, Med. Sci. Law, 4 (1964) 44-46. 17 A. K. Mant, Autopsy diagnosis of accidental hypothermia, J. Forensic Med., 16 (1969) 126-129. 18 H. Duguid, R. G. Simpson and J. M. Stowers, Accidental hypothermia, Lancet, 2 (1961) 1213--1219. 19 U. Kreinsen und C. M. Busing, Experimentelle Herzmuskelnekrosen bei der Ratte nach Gabe von 1-Noradrenaline und Strophantin, Virchows Arch. A, 367 (1975) 4757. 20 M. Alavaikko, J. Hirvonen and 0. R&&en, Fatty change in papillary heart muscle and in its arterioles, Acta Pathol. &and., 78 (1970) 458-472. 21 E. Trube-Becker, Zur Begutachtung beim Tod durch Unterkiihlung, Z. Rechtsmed., 59 (1967) 211-227.