Homicidal asphyxia

Homicides due to asphyxia are relatively uncommon. To better understand the presentation of such cases, the files of the Bexar County Medical Examiner's Office were reviewed from January 1, 1985, through December 31, 1998, for all such homicides. A total of 133 cases were found. The largest category was ligature strangulation with 48 deaths (21 male, 27 female). Petechiae were present in the conjunctivae and/or sclerae in 86% of the cases; fractures of the hyoid and/or thyroid cartilage were present in 12.5%. There were a total of 41 deaths from manual strangulation (27 female, 14 male). Petechiae were present in 89% of the cases. In cases of manual strangulation, fractures of the hyoid, thyroid, or cricoid cartilage were found in all the male victims and slightly more than one half of the female victims. Twenty-six cases of suffocation were found; 20 of the victims were < or =2 years of age. Only 1 of these children had petechiae and/or scleral hemorrhage. Five deaths were due to choking. Three of the deaths involved adults who were gagged; 2 deaths involved infants with foreign material pushed into the mouth. Other categories of asphyxia were as follows: 9 deaths due to more than one form of asphyxia; 1 death due to hanging, and 3 deaths due to drowning. Rape was the motive in 66% of the female victims of ligature strangulation and 52% of those due to manual strangulation.     

Histological examination of the temporal bone in medicolegal cases of asphyxia

Histological findings of the temporal bone in 23 autopsy cases of various asphyxial fatalities were studied. The temporal bones of 12 cases who died of tumors including mammary cancer, gastric cancer, myxoma of heart and craniopharyngioma, the bones of 3 cases of heart attack and the bones of 17 cases who died of various poisoning (barbiturate, amphetamine, paraquat and alcohol) were used as controls. In drowning, the primary finding was hemorrhage in the mastoid air cells of the bilateral temporal bones. In cases of strangulation by ligature, hemorrhage and edema of the cochlear duct in the inner ear as well as hemorrhage in the mastoid air cells were demonstrated bilaterally. In contrast, congestion and edema in the mastoid air cells and inner ear were found in cases of manual strangulation but there was no hemorrhage. From these results, the histological examination of the temporal bone is useful as an adjunct procedure for diagnosing the cause of asphyxia. Differentiation between drowning, strangulation by ligature and manual strangulation may be possible by observing hemorrhages or their absence in the mastoid air cells and inner ear.     

Aquatic fatalities--a systematic retrospective analysis

In a retrospective analysis of the autopsy material (n = 5,767) of the Institute of Legal Medicine of the Hanover Medical School covering the period of 1998-2007, all aquatic fatalities were evaluated, categorized and systematically compared under epidemiological and forensic criteria. The total of 156 cases of death by drowning (2.7 % of all autopsies) included 38 bathtub drownings and 28 deaths in the water for which no pathological anatomical cause of death could be reliably demonstrated. A control group (n = 221) was investigated for the presence of aqueous liquid in the sphenoid sinuses and compared with the findings of the drowning cases without signs of putrefaction. About 16 % of the control cases had fluid in the sphenoid sinuses compared with 57.6 % in the drowning group. Most of the drowning victims were men (60.9 %), whereas in the group of bathtub drownings the majority were women. More than half of the drowning cases (n = 89) could be classified as accidents. The individual groups showed a different incidence of findings associated with drowning.     

A sandwich enzyme immunoassay for pulmonary surfactant protein D and measurement of its blood levels in drowning victims

A sensitive sandwich enzyme immunoassay for human pulmonary surfactant protein D (SP-D) was developed and used to examine the blood SP-D levels of drowning victims. Human SP-D was purified from amniotic fluid by chromatographic methods, and an antibody against human SP-D was prepared. A polystyrene ball coated with anti-SP-D IgG was incubated with purified human SP-D, and then with anti-SP-D Fab'-peroxidase conjugate. Peroxidase activity bound to the polystyrene ball was assayed by fluorometry using 3-(4-hydroxyphenyl)propionic acid as the hydrogen donor. The detection limit of human SP-D was 5.2 pg per assay tube. Examination of cross-reactions of this sandwich enzyme immunoassay with proteins from other human organs showed it to be highly specific for lung, and Northern blot analysis detected specific SP-D mRNA expression only in lung. The SP-D concentration of normal human serum was 6.4+/-2.7 (mean+/-S.D.) ng ml(-1) (n=20). The recovery rates of 0.52 ng and 5.2 ng SP-D added to 5 microl normal human serum were 93.6+/-2.7% and 93.6+/-6.1%, respectively. Blood SP-D levels of victims from the saltwater drowning group (n=14) revealed higher concentrations (105.8+/-53.7 ng ml(-1)), while freshwater drowning victims (n=12) were estimated to be 74.1+/-43.9 ng ml(-1). The SP-D levels of 15 subjects who died of hemorrhage (n=5), heart failure (n=8), traumatic shock (n=1), and electrocution (n=1) were lower (22.0+/-8.5 ng ml(-1)), and those of asphyxia victims (n=10) were slightly higher (36.2+/-17.1 ng ml(-1)) than those of other causes of death, except for drowning. These results suggest that in drowning victims, SP-D flowed into the systemic circulation by physiological and physical mechanisms, and the differences of blood SP-D levels between saltwater drowning and freshwater drowning victims are presumed to be influenced by the type of agony and/or the length of survival time in water.     

Lung histology in experimental drowning

Experiments were carried out on anesthetized rats which had to aspirate actively watery fluids of different osmolarities (range: freshwater--2.9% NaCl solution) by a tracheotomy tube. The cytologic and histological alterations which are to be found are mainly of osmotic origin. In aspiration of hypotonic solutions macroscopy shows the well-known emphysema aquosum. Corresponding to the structure of the respiratory system, the histological alterations show areolar limitations. The influx of fluids causes a wide range of reactions from the development of an alveolar-interstitial edema in combination with intracellular and intercellular vesiculation, karyolysis with swollen homogenized nuclei of the subendothelial, septal, and epithelial cells to a necrosis of all the cellular elements. A pronounced microangiopathy with edema of the vascular walls, a hydrops of the myocytes containing large vacuoles and perivascular edema with dilated lymphatic channels are likewise to be found. The alveolar macrophages are considerably increased. Sporadic ruptures of the alveolar walls and microhemorrhages occur. In salt water drowning alterations of the shape of both the erythrocytes (thorn-apple form) and the alveolar epithelium in combination with a striking of the pneumocytes and villous transformation prevail. Besides, these are capillary hyperemia and sludge. In a careful specimen analysis a differentiation of the findings between vital reactions and postmortem fluid impact is possible.     

Fatalities in the bathtub

A retrospective analysis concerning deaths in the bathtub was carried out in the Institute of Legal Medicine in Hamburg. The study includes 245 death cases between 1971 and 1988 (1% of all autopsies). 66 cases proved to be natural deaths, 76 were classified as suicides, 39 as accidents and 13 as homicides; 51 fatalities remained unclear with respect to one of these groups. Among the natural deaths sudden cardiac deaths were dominating (n = 39), among the suicides the intoxications (n = 37) and electrocutions (n = 20), and among the accidents the intoxications by carbon monoxide (n = 17) and electrocutions (n = 12). Out of 13 homicides only 2 were committed directly in the bathtub: One by drowning of a child and one by electric current via a hair dryer; in the other cases the dead body was put into the bathtub post mortem. About 50% of the victims were alcoholized. Signs of drowning were present in about 40% of all cases; the most frequent finding was emphysema aquosum.     

Diagnostic dilemma of sudden deaths due to acute hemorrhagic pancreatitis

Sudden death due to acute pancreatitis has been rarely determined. A review of 3305 autopsies performed between 1991 and 2001 at the Council of Forensic Medicine found 12 cases (0.36%) with sudden death due to acute hemorrhagic pancreatitis without symptoms. A history of chronic alcohol ingestion was obtained from family in four cases (33%), and no stones were found in the bile ducts or in the gall bladders. During the autopsies, hemorrhage and edema were localized on the head of the pancreas in three cases and the whole pancreas in nine cases. The most common extrapancreatic pathology was found in the lung including pulmonary edema, alveolar hemorrhage, pleural effusion, and pulmonary congestion. There was no correlation between pulmonary and pancreatic damage. It is suggested that the forensic pathologists who are dealing with sudden unexpected death must not ignore the examination of pancreatic and extrapancreatic regions to avoid missing acute pancreatitis.     

Classification of Asphyxia: The Need for Standardization

Abstract: The classification of asphyxia and the definitions of subtypes are far from being uniform, varying widely from one textbook to another and from one paper to the next. Unfortunately, similar research designs can lead to totally different results depending on the definitions used. Closely comparable cases are called differently by equally competent forensic pathologists. This study highlights the discrepancies between authors and tries to draw mainstream definitions, to propose a unified system of classification. It is proposed to classify asphyxia in forensic context in four main categories: suffocation, strangulation, mechanical asphyxia, and drowning. Suffocation subdivides in smothering, choking, and confined spaces/entrapment/vitiated atmosphere. Strangulation includes three separate forms: ligature strangulation, hanging, and manual strangulation. As for mechanical asphyxia, it encompasses positional asphyxia as well as traumatic asphyxia. The rationales behind this proposed unified model are discussed.     

Pulmonary surfactant-associated protein A levels in cadaveric sera with reference to the cause of death

Pulmonary surfactant-associated protein A (SP-A) is an exclusively lung specific protein, and is considered to leak into the blood stream in alveolar septal damage. In this study we examined the serum SP-A level in forensic autopsy materials using an enzyme immunoassay with monoclonal antibodies to assess the postmortem level in relation to the cause and mode of death. Although a gradual postmortem degradation should be taken into consideration, topological relationship of serum level seemed to be fairly stable (arterial> or =venous blood in most cases), indicating no evident influence of postmortem diffusion. Significant elevation of serum SP-A (76.7-250 ng/ml in left heart blood) was observed in hyaline membrane diseases from various causes independent of the postmortem intervals (<30 h). However, mean SP-A levels in postmortem heart blood were usually low in asphyxia including hanging, strangulation and choking (left, 25.5 ng/ml; right, 22.3 ng/ml), polytrauma (left, 13.1 ng/ml; right, 9.0 ng/ml) and stab wound to the neck (left, 34.1 ng/ml; right, 29.4 ng/ml). Prominent elevation was noted in a case of fatal strangulation with complication of idiopathic interstitial pneumonia, and also in some deaths due to drowning, burns in fires, blunt and gunshot chest injuries. These findings indicated that postmortem elevation of serum SP-A levels was associated with alveolar septal damage due to inflammation, mechanical and physical stresses, which caused leakage of SP-A into the bloodstream.     

Drowning without aspiration: is this an appropriate diagnosis?

It has been reported that 10-15% of drowning victims do not aspirate water. We have revisited the original studies quoted to reach this conclusion and find it is without foundation. Sudden cardiac standstill is known to occur on land and, therefore, may also occur when the victim is in water. In the absence of the common finding of significant pulmonary edema in the victim's respiratory system, to conclude his or her death was caused by "drowning without aspiration" is unwise. All causes of sudden death that might occur in which respiration may not take place should receive serious consideration when examining bodies with such findings that are found in water.     

A frozen newborn infant: froth in the air-passage after thawing

We performed an autopsy on a frozen newborn infant who was found in a freezer at -18 degrees C. After thawing, froth emerged from the nostrils and was present in the trachea. Sometimes froth may be seen in the air-passage in cases of strangulation and drowning. In our case, however, there was neither proof of asphyxia due to strangulation nor drowning. The existence of the froth indicates that the infant was probably in a state of respiratory distress before death. Histologic findings of the lung showed that the infant did not suffer from respiratory disorders such as respiratory distress syndrome. Karyopyknosis and vacuolation of the keratinocytes, shrinkage of the hepatocytes, dilatation of the sinusoid, spaces between heart muscle fibers and deep staining of the nuclei and hemolysis were characteristic in our case. This case shows that froth persists in the internal air-passage for a long time as a result of freezing. Moreover, the froth in the air-passage, along with the findings of the lungs, demonstrates that the newborn infant was born alive.     

Homicide-suicide in Hong Kong, 1989-1998

This study provides the first systematic research of homicide-suicide (HS) in a Chinese society. Data were drawn from the HK Homicide Monitoring Data-base computer file derived from investigation and death reports held by the HK Police Force and the Coroner's Court. During the 10-year study period, 56 events involving 133 deaths were identified. The majority of offenders were males (75%) and most victims were female (64%). The mean age of offenders and victims were 41.9 and 32.3 years, respectively. Spouses and lovers comprised the majority of victims (46.4%) followed by child victims (36%). Most HS events were motivated by separation or termination of marital or sexual relations (39%), economic reasons (25%) and other domestic disputes (20%). The most frequent modes of killing were strangulation/suffocation (26%), stabbing/chopping (24%), followed by gassing/poisoning (14%) and falling from a height (14%). The commonest method of suicide was falling from a height (48%). It was followed by gassing/poisoning (22%) and strangulation/suffocation (13%). Depression (18.3%) was found to be the commonest mental disorder. Most offenders were from low-socio-economic background. Two-third were unemployed and 76.6% had 9 or less years of education. HS in HK were distinguished from those reported in the western literature in respect to the high relevance of economic factors, the absence of mercy killing between old couples, a higher percentage of pedicide-suicides and the infrequent use of firearms.     

Homicide–suicide in Hong Kong, 1989–1998

This study provides the first systematic research of homicide–suicide (HS) in a Chinese society. Data were drawn from the HK Homicide Monitoring Data-base computer file derived from investigation and death reports held by the HK Police Force and the Coroner’s Court. During the 10-year study period, 56 events involving 133 deaths were identified. The majority of offenders were males (75%) and most victims were female (64%). The mean age of offenders and victims were 41.9 and 32.3 years, respectively. Spouses and lovers comprised the majority of victims (46.4%) followed by child victims (36%). Most HS events were motivated by separation or termination of marital or sexual relations (39%), economic reasons (25%) and other domestic disputes (20%). The most frequent modes of killing were strangulation/suffocation (26%), stabbing/chopping (24%), followed by gassing/poisoning (14%) and falling from a height (14%). The commonest method of suicide was falling from a height (48%). It was followed by gassing/poisoning (22%) and strangulation/suffocation (13%). Depression (18.3%) was found to be the commonest mental disorder. Most offenders were from low-socio-economic background. Two-third were unemployed and 76.6% had 9 or less years of education. HS in HK were distinguished from those reported in the western literature in respect to the high relevance of economic factors, the absence of mercy killing between old couples, a higher percentage of pedicide–suicides and the infrequent use of firearms.     

A microbiological test for the diagnosis of death by drowning

The present study was aimed at demonstrating the diffusion of sea water or freshwater into the bloodstream as a consequence of water aspiration due to drowning. The study was carried out on 42 study group subjects who died by drowning in salt water (20 cases) and freshwater (22 cases) and 30 control group subjects who died from causes other than drowning. For 25 cases we obtained water samples from the aquatic locations where the victims were found. The blood samples of study and control groups were analyzed to search for faecal coliforms (FC) and faecal streptococci (FS) bacteria. The presence of FC and FS was showed by the development of blue and red colonies, respectively. From left ventricular (LV) and right ventricular (RV) blood cultures of the 20 sea drowning victims we always isolated FS and FC, whereas 19 (95%) femoral arterial (FA) and 18 (90%) femoral venous (FV) blood cultures were positive for both faecal bacteria. Related to freshwater victims, LV blood cultures showed FS presence for all the 22 cases studied (100%) and FC presence for 20 cases (90.91%). Blood cultures from RV, FV, and FA showed various patterns of faecal bacteria presence. The analysis of 25 water samples from the aquatic locations where the victims were found showed the presence of FC and FS bacteria. Blood cultures from the 30 control subjects uniformly proved the absence of faecal bacteria.     

Intrapulmonary aquaporin-5 expression as a possible biomarker for discriminating smothering and choking from sudden cardiac death: a pilot study

The diagnosis of mechanical asphyxia as a cause of death, especially smothering and choking lacking evident injury, is one of the most difficult tasks in forensic pathology. The present study investigated the intrapulmonary expressions of aquaporins (AQPs; AQP-1 and AQP-5), as markers of water homeostasis, in forensic autopsy cases (total n=64, within 48 h postmortem) of mechanical asphyxiation due to neck compression (strangulation, n=24), including manual/ligature strangulation (n=12) and atypical hanging (n=12), smothering (n=7) and choking (n=8), compared with sudden cardiac death (n=14) and acute brain injury (n=11). Quantification of mRNA using a Taqman real-time PCR assay system demonstrated suppressed expression of AQP-5, but not AQP-1, in smothering and choking, compared with that in strangulation as well as sudden cardiac death and acute brain injury death. Immunostaining of AQP-5 was weakly detected in a linear pattern in the type I alveolar epithelial cells in smothering and choking cases, while cardiac and brain injury death showed marked positivity, and most strangulation cases had AQP-5-positive granular aggregates and fragments in intra-alveolar spaces. These observations indicate a partial difference in pulmonary molecular pathology among these causes of death, suggesting a procedure for possible discrimination of smothering and choking from sudden cardiac death.     

Pulmonary edema in fatal heroin overdose: immunohistological investigations with IgE, collagen IV and laminin - no increase of defects of alveolar-capillary membranes

Pulmonary edema complicating heroin overdosage is a well recognized entity and regarded as the major mechanism contributing to death in heroin addicts. It's pathogenesis is unknown, several mechanisms are discussed: hypoxia-induced increase of pulmonary capillary permeability, depressed myocardial contractility, centrally induced respiratory depression, primary toxic effects on the alveolar capillaries and acute anaphylactic shock. The present study included opiate-related deaths (n=23) and a control group of sudden cardiovascular deaths (n=12) to verify the hypothesis, that defects of the alveolar capillary membranes and/or an acute anaphylactic reaction leads to pulmonary congestion, edema and hemorrhages. Lung specimens were obtained from these 35 autopsies of persons autopsied in the Institute of Forensic Medicine, University of Bonn, in 1997 and 1998. All specimens were examined with hematoxylin-eosin, prussian blue and investigated with immunohistological methods using primary antibodies against collagen IV, laminin and IgE. Defects of the basal laminae of the alveoli were found, demonstrated by laminin and collagen IV, and the number of IgE-positive cells was counted in both groups. There was an increased but not significant number of IgE-positive cells in the heroin-group and defects of the epithelial and endothelial basal laminae were found in both groups without significant differences.     

Determining the type of drowning based on the levels of blood in the thoracic duct lymph

The degree of lymphogemy in persons who died of different causes (including drowning) was studied by histologic analysis of the thoracic lymphatic ducts. It was found that quantitative estimation of the presented feature makes it possible to estimate the specific type of drowning which depends on the level of venous hypertension in the system of superior vena cava. This phenomena is strongly marked in spastic and mixed types of drowning and is absent in aspiration and reflex types.     

Forensic aspects of 40 accidental autoerotic deaths in Northern Germany

Between 1983 and 2003, 40 accidental autoerotic fatalities have been investigated. in the Institute of Legal Medicine in Hamburg. Only 50% (n = 20) were autopsied (13 legal autopsies, 6 for scientific purposes and 1 for an insurance company). All the victims were males, aged between 13 and 79 years (among them five children and adolescents, the deceased mainly between 20 and 40 years). The paraphiliacs utilized a great range of devices and props as fetishism, sexual aids or pain-stimulating agents, like intimate feminine garments, ropes, chains, bondages, locks, pornographic magazines, condoms, rubber items, and chemical anaesthetics. The cause of death was strangulation in 20 cases (17× hanging, 3× ligature strangulation), 11× suffocation (8× under plastic bags, 3× with face-masks, 2× thoracic compression, 1× positional asphyxia, and 1× cocaine intoxication). Five cases without autopsy remained unclear because of missing morphological and toxicological findings; it could not be differentiated between asphyxiation/intoxication/natural disease, although the scene characteristics seemed to be typical for autoerotic deaths. It is emphasized that the findings at the scene, the morphological and toxicological examination of the dead body (full autopsy as prerequisite) by experienced investigators and the personal history of the deceased have to be evaluated very carefully and intensely to reconstruct the accidental fatal autoerotic course accurately and undoubtedly (to exclude the possibility of sexual homicide, neglected killing, or suicide).     

A contribution to a possible differentiation between SIDS and asphyxiation

The singular and combined appearance of conjunctival petechiae, of acute pulmonary emphysema and of signs of aspiration was evaluated in resuscitated and non-resuscitated children dying of SIDS (n=115), of other causes of natural death (n=17), of severe head injury (n=10) and of asphyxiation/strangulation (n=7). Conjunctival petechiae occurred in all of the asphyxiated victims and in five out of 10 children dying of severe head injury, but were exclusively found in four resuscitated babies and one baby with questionable resuscitation trials of the SIDS-group (4%), furthermore in one resuscitated child dying of a congenital heart defect. Acute pulmonary emphysema was detected in six out of the seven children of the asphyxiation/strangulation group, in two resuscitated children with head injury and in five resuscitated babies dying of SIDS. Both parameters were observed exclusively in the asphyxiation/strangulation group (71% of the cases) but not in the control cases. Therefore, it can be concluded that the simultaneous appearance of conjunctival petechiae and of acute pulmonary emphysema strongly indicates death by asphyxiation.     

Intra-familial child homicide in Finland 1970-1994: incidence, causes of death and demographic characteristics

The purpose of this study was to investigate all child homicides for the 25-year period, 1970-1994 in Finland and to analyse the specific characteristics of the filicide cases. A total of 292 child homicides occurred during this period. In 201 (69%) cases the offender was a parent or a stepparent of the child. Altogether, 173 (59%) of the victims were boys and 119 (41%) were girls. For the closer examination of the filicide cases we excluded the neonaticide and homicide-suicide cases. Consequently, we report on 70 filicide victims. Of these victims, 42 (60%) were boys and 28 (40%) were girls. Twenty six (37%) of the children were killed before the age of 1 year and 53 (79%) before the age of 5 years. The offender was the mother in 43 (61%) cases and the father or the stepfather in 26 (37%) cases. The victims of the mothers were younger than those of the fathers. The most frequent causes of death were head injuries, drowning and suffocation. The most common means of assault were battering, drowning and strangulation. One in two of the fatally battered children had a documented history of previous abuse.