Mechanism of Death in Hanging: A Historical Review of the Evolution of Pathophysiological Hypotheses

Abstract: In cases of hanging, the exact mechanism leading to death has yet to be elucidated. Most of our contemporary knowledge is still based on writings from the end of the 19th and the beginning of the 20th century. This article reviews the historic experiments that shaped our current theories. Medico‐legal textbooks written in English and French from 1870 to 1930 were reviewed. Various animals, such as rabbits, mice, and dogs, have been used to develop animal models of hanging. Limited human studies on cadavers and judicial hangings have provided some additional insight into the pathophysiology of death by hanging. The main pathophysiological theories described were respiratory asphyxia, interruption to cerebral blood flow because of occlusion of vessels in the neck, and cardiac inhibition secondary to nerve stimulation. The relative contributions of each of these theories to death in cases of hanging is still debated today.     

Agonal Sequences in Four Filmed Hangings: Analysis of Respiratory and Movement Responses to Asphyxia by Hanging*

Abstract: The human pathophysiology of asphyxia by hanging is still poorly understood, despite great advances in forensic science. In that context, filmed hangings may hold the key to answer questions regarding the sequence of events leading to death in human asphyxia. Four filmed hangings were analyzed. Rapid loss of consciousness was observed between 13 sec and 18 sec after onset of hanging, closely followed by convulsions (at 14–19 sec). A complex pattern of decerebration rigidity (19–21 sec in most cases), followed by a quick phase of decortication rigidity (1 min 00 sec–1 min 08 sec in most cases), an extended phase of decortication rigidity (1 min 04 sec–1 min 32 sec) and loss of muscle tone (1 min 38 sec–2 min 47 sec) was revealed. Very deep respiratory attempts started between 20 and 22 sec, the last respiratory attempt being detected between 2 min 00 sec and 2 min 04 sec. Despite differences in the types of hanging, this unique study reveals similarities that are further discussed.     

Agonal sequences in a filmed suicidal hanging: analysis of respiratory and movement responses to asphyxia by hanging

The forensic literature on the pathophysiology of human hanging is still limited. Therefore, forensic pathologists often feel uncomfortable when confronted with related questions. Here presented is the filmed suicidal hanging of a 37-year-old man. This recording allows a unique analysis of agonal movement sequences: loss of consciousness (13 sec), convulsions (15 sec), decortication rigidity (21 sec), decerebration rigidity (46 sec), second decortication rigidity (1 min 11 sec), loss of muscle tone, (1 min 38 sec) and last isolated muscle movement (4 min 10 sec). As for respiratory responses, very deep respiratory attempts started at 20 sec. Respiratory movements progressively decreased and completely stopped at 2 min. Despite the fact that extending the presented data on all cases of hanging asphyxia would be a mistake, this case gives a very interesting insight into movement and respiratory response to asphyxia by hanging.     

Agonal Sequences in Eight Filmed Hangings: Analysis of Respiratory and Movement Responses to Asphyxia by Hanging*

Abstract: It has been proposed that filmed hangings may hold the key to a better understanding of human asphyxia, and The Working Group on Human Asphyxia was formed to systematically review and compare these video recordings. This study analyzed eight filmed hangings. Considering time 0 to represent the onset of the final hanging, rapid loss of consciousness was observed (at 8–18 sec), closely followed by convulsions (at 10–19 sec). A complex pattern of decerebrate rigidity and decorticate rigidity then followed. Between 1 min 38 sec and 2 min 15 sec, muscle tone seemed to be lost, the body becoming progressively flaccid. From then on, isolated body movements were observed from time to time, the last one occurring between 1 min 2 sec and 7 min 31 sec. As for the respiratory responses, all cases presented deep rhythmic abdominal respiratory movements (last one between 1 min 2 sec and 2 min 5 sec).     

家兔限制性体位窒息模型中的LDH/CHE活性变化

目的 探讨家兔体位性窒息模型中乳酸脱氢酶(LDH)和胆碱脂酶(CHE)活性变化与窒息死亡的关系。方法 建立动物模型，检测膈肌、腓肠肌，以及血清中LDH、CHE的活性变化。结果 实验组家兔膈肌与腓肠肌相比，LDH活性明显下降，且差异显著(P＜0.05)，CHE活性差异无显著性(P＞0.05)；2组膈肌比较，LDH活性明显下降，有显著性差异(P＜0.05)，CHE活性无显著性差异(P＞0.05)；实验组血清中LDH活性比对照组明显升高，有显著性差异(P＜0.05)，2组CHE活性无显著性差异(P＞0.05)。结论 膈肌中LDH活性的降低与固定双上肢悬挂体位具有相关性。     

体位性窒息对心、肺功能影响的实验研究

通过从股静脉将漂浮导管插入肺动脉的方法 ,检测悬挂前、悬挂期间和临终阶段呼吸、肺动脉压、心输出量的变化,探讨体位性窒息对心、肺功能影响及其在死亡中所起作用。结果:(1)悬挂前呼吸频率平稳 ,悬挂期间逐渐加快 ,临终前呈无规律状态 ;(2)悬挂期间及临终时肺动脉压比悬挂前明显升高;(3)悬挂前及悬挂期间的心输出量基本平稳 ,临终时比悬挂前及悬挂期间明显下降。本研究发现 ,悬挂可致呼吸失调 ,机体缺氧 ,导致心、肺功能障碍 ,属肺性死亡。其特征为呼吸停止是原发性的 ,心跳停止是继发的。     

Epidemiology of suicide by hanging in Transkei, South Africa

To describe the epidemiology of suicide by hanging, in Transkei region of South Africa. This is a record review of the autopsy register from 1993 to 2003. There is an increasing trend of hangings from 5.2 per 100,000 to 16.2 in 2003. The highest was in the 20- to 29-year age group. The least number of hangings of 2.2 per 100,000 was in those over 70 years of age. Males (86.4%) outnumber females. The ratio of male to female suicide is 6.4:1. The 2 youngest suicide victims were also males aged 9 years. Peak of these hangings is in May and November and least in September. There is increasing trend of hanging especially among young adults between 20 and 29 years old.     

Animal-related fatalities--part II: characteristic autopsy findings and variable causes of death associated with envenomation, poisoning, anaphylaxis, asphyxiation, and sepsis

In addition to blunt and sharp trauma, animal-related fatalities may result from envenomation, poisoning, anaphylaxis, asphyxiation, and sepsis. Although the majority of envenomation deaths are caused by hornets, bees, and wasps, the mechanism of death is most often anaphylaxis. Envenomation resulting from the injection of a poison or toxin into a victim occurs with snakes, spiders, and scorpions on land. Marine animal envenomation may result from stings and bites from jellyfish, octopus, stonefish, cone fish, stingrays, and sea snakes. At autopsy, the findings may be extremely subtle, and so a history of exposure is required. Poisoning may also occur from ingesting certain fish, with three main forms of neurotoxin poisoning involving ciguatera, tetrodotoxin ingestion, and paralytic shellfish poisoning. Asphyxiation may follow upper airway occlusion or neck/chest compression by animals, and sepsis may follow bites. Autopsy analysis of cases requires extensive toxinological, toxicological, and biochemical analyses of body fluids.     

鼠窒息后缺氧诱导因子1-α在心、肺中的表达

目的研究大鼠机械性窒息死亡后缺氧诱导因子1-α(HIF1-α)在心、肺中的表达变化,探讨其作为窒息死亡诊断指标的可行性。方法制作大鼠缢死模型,分别于窒息死后及正常断颈处死后0、2、6、24h时间段取材,用免疫组织化学、RT-PCR方法测定缢死后HIF1-α在心肌和肺组织中的分布和表达变化。结果HIF1-α在窒息组的心肌和肺组织中表达,窒息组和对照组在各时间段表现出明显差异,对照组仅在死后2、6、24h阳性表达。窒息死亡组可见核阳性表达,而对照组未见核阳性表达。半定量RT-PCR结果显示HIF1-α在0h时各组未见升高,但在2、6、24h窒息组则较对照组升高。结论心和肺组织HIF1-α表达核阳性细胞的出现,可以作为窒息死亡的特征性表现。     

兔皮肤钝器伤IL-1β、COX-2和MCP-1 mRNA表达与法医学应用

目的应用荧光定量PCR技术检测兔皮肤钝器伤后IL-1β、COX-2和MCP-1mRNA的时序性表达规律,分析其与损伤时间的关系。方法分别在兔耳皮肤钝器伤后<0.5h,0.5h,1h,2h,3h,4h,5h,6h,8h,12h,24h,1d,3d,7d和死后10min,0.5h,1h取材,一步法提取组织总RNA,逆转录合成cDNA第一条链,荧光定量PCR检测IL-1β、COX-2和MCP-1mRNA逆转录合成第一条cDNA链的拷贝数,作统计学分析。结果IL-1βmRNA在钝器伤后<0.5h表达显著增强(P<0.001),0.5h达到峰值,至第2d降至基本水平;COX-2mRNA于创伤后0.5h表达显著增强(P<0.05)并持续强表达至24h开始下降,第2d降至正常;MCP-1 mRNA在钝器伤后于1h表达显著增强(P<0.05),于3h出现表达峰,至第3d降至正常;3个指标在死后各时间组与正常对照无明显表达差异。结论检测皮肤IL-1β、COX-2和MCP-1mRNA可对早期损伤时间的推断提供帮助,并且这三个指标都可以鉴别生前伤和死后伤。     

Comparison of patterns of decomposition in a hanging carcass and a carcass in contact with soil in a xerophytic habitat on the Island of Oahu, Hawaii

Decomposition studies were conducted to determine differences in rates and patterns of decomposition of carcasses hanging and exposed on the surface of the soil. These studies were conducted between 17 October and 17 December 1997 inside of Diamond Head Crater on the island of Oahu, Hawaii. The animal model was the domestic pig. Sus scrofa. The rate of biomass removal from the hanging carcass was significantly slower than that observed for the control carcass during the bloat and decay stages of decomposition. Internal temperatures for the control carcass were elevated above the ambient air temperatures during the earlier stages of decomposition (bloated and decay), while those recorded for the hanging carcass approximated the ambient air temperatures. There was a greater diversity of arthropod species recorded and numbers of individuals observed were higher for the control carcass. A significant site of arthropod activity was observed on the surface of the soil immediately under the hanging carcass and this became the primary site of arthropod activity as decomposition progressed.     

自杀方式与性别和年龄关系548例分析

目的分析国内5个城市地区采取不同自杀方式人群的性别和年龄特征。方法收集上海、金华、武汉、娄底、都匀城市地区警方处理的548例自杀案例,根据自杀方法将案件进行分类,研究各种自杀方法的人群年龄和性别特征,结果在各种自杀方式的年龄分析中,高坠和自缢的自杀者平均年龄最大(约55岁),溺水、自缢次之(约49岁)、口服毒物较为年轻(约45岁),而CO中毒自杀者平均年龄最小(约37岁)。在自杀方式的性别差异中,男性更多地出现了锐器自杀(52:24),自缢(67:33)和高坠(55:45),女性则在溺水自杀中占据多数(58:42)。结论每种自杀方式涉及到的人群的性别和年龄特征差异明显,CO中毒自杀的自杀者最为年轻;男性更倾向于用机械性损伤的方式来自杀。     

Cluster hanging suicides in the young in South Australia

Retrospective review of hanging suicides in individuals aged ≤ 17 years was undertaken at Forensic Science South Australia, Australia, over two 5-year periods: 1995-1999 and 2005-2009. Seven cases of hanging suicides were identified from 1995 to 1999, with a further 14 cases from 2005 to 2009, an increase of 100% (p < 0.001). Hanging accounted for 33.3% of all suicides in this age group (7/21) from 1995 to 1999, compared with 93.3% of the total number of suicides (14/15) in the second 5-year period. In contrast, Australian national data from 1998 and 2008 showed a 30% decrease in hanging suicides in the young, from one case/100,000 population in 1998 to 0.7 in 2008. Cluster suicides occur in the young and are often initiated by direct communication. As it is possible that Internet-based social sites may facilitate this phenomenon, investigations should include an evaluation of the victim's Internet access given the potential risk of similar actions by peers.     

Accidental Hanging Deaths in Children in Konya,Turkey Between 1998 and 2007*

Abstract: In general, hanging cases are the result of suicide, and accidental and homicidal hanging cases are rarely seen. This study retrospectively investigated 4571 death examinations and autopsies that were performed at The Konya Branch of the Forensic Medicine Council (Turkey) between 1998 and 2007; hanging was involved in 201 (6.5%) of the cases. There were a total of 13 accidental hanging cases, where 12 of these involved children. In seven of the cases, the accidental hanging involved a scarf that wraps around swing‐like cradles and is intended to prevent infants from falling down. It was concluded that accidental hanging deaths can be reduced by replacing swing‐like cradles with cribs that are designed for children, removing ropes in and around the house, and preventing children from reaching and/or playing with rope‐like objects.     

大鼠急性心肌缺血后脑钠肽、c-fos基因的表达及法医学意义

目的研究大鼠在急性心肌缺血（acute myocardial ischemia,AMI）后目的基因脑钠肽（brain natriuretic peptide,BNP）和c-fos的mRNA表达变化与AMI发生后所经历时间的关系,为法医病理学鉴定心源性猝死提供依据。方法用结扎法制作大鼠AMI动物模型,结扎成功后观察时间组为10、30、60min和3h,用RT-qPCR、普通PCR检测目的基因BNP和c-fos的mRNA表达变化,同时行HE染色。比较不同时间组间的结果差异。结果RT-qPCR结果显示,BNP在3h组的表达量高于正常组、10min组、30min组及60min组,有显著性差异（P〈0.05）,c-fos除正常组与10min组之间、30min组与3h组之间无显著性差异（P≥0.05）以外,其他各组间均有显著性差异（P〈0.05）,并以60min组c-fos基因的表达量最多。普通PCR未见目的基因不同时间的组间差异。HE染色仅在实验组3h组偶见局部嗜酸性增强、肌纤维呈波浪状等改变。结论c-fos基因可能作为缺血发生30min后的辅助诊断指标。RT-qPCR方法较适合早期AMI的诊断。     

Petechiae in hanging: a retrospective study of contributing variables

Petechiae, one of the classic signs of asphyxia, are thought to be more frequently observed in cases of hanging where part of the body is supporting the victim's weight, ie, cases of incomplete hanging. However, there is very little evidence-based medicine to support this claim. The present study is intended to evaluate the relationship between petechiae and the type of hanging (complete vs. incomplete). Furthermore, several other variables were analyzed to determine if they contribute significantly to the presence of petechiae. An 8.5-year retrospective study of 206 cases of death by hanging reviewed autopsy reports for the presence of petechiae. For each case, the following information was also compiled: gender and age, height and weight, body mass index, the type of hanging (complete or incomplete suspension), the type of ligature used (narrow or wide), and whether or not the victim had received cardiopulmonary resuscitation maneuvers. Statistical analysis revealed that the incidence was higher among incomplete hanging victims compared with cases of complete suspension and that the incidence of petechiae varied inversely with the height of the victims. The other factors were not shown to contribute significantly to the presence of petechiae.     

Six‐Year Retrospective Study of Suicidal Hangings: Determination of the Pattern of Limb Lesions Induced by Body Responses to Asphyxia by Hanging*

Abstract: The objective of the present study was to estimate the proportion of hanging victims presenting with limb lesions, to compare this rate between hanging in restraint spaces and in more open settings, and to describe the usual pattern of limb lesions associated with hanging. Two hundred and seven cases of suicidal hanging were retrospectively reviewed and compared to 45 homicidal nonhanging strangulation victims. Bruises incidence was significantly lower in hanging victims (19.8%) compared to homicidal strangulation victims (55.6%). Bruises were more commonly encountered in restraint areas such as closets and staircases (56.3% and 66.7%, respectively) than in more open settings such as barn, bridge, fence, and park. Limb bruises on hanging victims were generally located on the posterior upper limb or the anterior lower limbs, whereas strangulation victims did not display this preferential bruises concentration. Possible suspicion criteria for limb bruises distribution are discussed, in relation to physiopathology of human asphyxia by hanging.     

Cultural influence on the incidence and choice of method of suicide in Saudi Arabia.

The present study was undertaken to explore how racial and cultural factors could possibly influence suicidal rates and patterns in Saudi Arabia. During the 10-year period from 1986 to 1995, 221 cases of suicide were examined at the Medico-legal Center, Dammam, Saudi Arabia. The suicide rate for the entire population averaged 1.1/100,000 population per annum. The male-to-female ratio was 4.5:1. The highest suicide rate was among the age group from 30 to 39 years (44.3%), followed by the age group from 20 to 29 years (32.6%), and the lowest suicide rate was among the age group <20 years (1.8%). The rate in the group >60 years was also low (3.2%). Immigrants formed 77% of the cases, and of these, Asians accounted for 70% of the overall cases and Indians showed the highest suicidal rates (43%). The most common means of suicide chosen was hanging (63%), followed by jumping from heights (12%) and gunshot injuries (9%); death from poisoning accounted for only 6% of cases. This study showed an increasing rate of suicide during the second 5-year period compared with the first 5-year period.     

Induction of hypoxia-inducible factor-1alpha in two kinds of rats asphyxiation death models

OBJECTIVE: To investigate the expression of hypoxia-inducible factor 1-alpha (HIF1-alpha) in the heart, lung, liver and kidney in rats died of two typical models of asphyxia. METHODS: Two asphyxia models were made and tissue samples of the dead rats were collected from different groups at various postmortem duration. The expression and the changes of HIF1-alpha in various tissues were examined by immunohistochemistry and image analysis techniques. Results Significant expression of HIF1-alpha was observed in the myocardial fibers, kidney cells, liver cells and lung cells in both asphyxia models, but not in the control group. The expression of HIF1-alpha in various tissues in the rat died of nitrogen gas breathing was found in the nuclei at 0 hour and the expression level decreased gradually thereafter. The HIF1-alpha expression level and duration in various tissues of the rat died of hanging were higher and longer than that of the former group, with a peak of the expression level observed 6 hours after death, and then started to decline in all tissues except the heart where the expression still showed an increase 24 hours after death. The control groups showed a steady expression in the cytoplasm but not in the nuclei. CONCLUSION: HIF1-alpha appears to be a valuable biomarker in the diagnosis of asphyxia within 24 hours after death.     

Lethal Laryngopyocele

A 44‐year‐old man collapsed after complaining of difficulty breathing. Layer dissection of the neck at autopsy revealed a large mixed internal and external laryngopyocele occluding the upper airway. It contained 30 mls of yellow‐gray pus. Mechanisms of death in laryngoceles involve obstruction of the opening into the larynx resulting in accumulation of mucus or air within the sac causing airway occlusion. Once infection supervenes, deaths in laryngopyocoeles result either from accumulated pus causing airway occlusion from a mass effect (as in the current case) or the discharge of pus into the airway causing death from aspiration. Sudden death in laryngopyoceles is a very rare event that requires careful dissection at autopsy to demonstrate the characteristics of the underlying lesion and the possible mechanism of death. Laryngopyocele should be considered in the differential diagnosis of natural conditions causing acute, potentially lethal, upper airway obstruction.