Quantitative Morphological Study of Larynx APUD-Cells in Asphyxial Type of Drowning in Fresh Water (Experimental Study).

An additional microscopic diagnostic sign has been identified for verification of asphyxial type of drowning. In white non-linear male rats (age 2 months) subjected to free drowning, significant hyperplasia of argyrophilic and morphofunctional activity of serotonin-containing APUD-cells of the laryngeal mucosa were revealed under conditions of acute anoxia in comparison with the intact control. These changes promote the development of laryngospasm, which prevents water penetration into the airways and lungs in asphyxial type of drowning. The presence of statistically significant hyperplasia of argyrophilic and morphofunctional activity of serotonin-containing APUD-cells of the laryngeal mucosa under conditions of acute anoxia can be used as an additional diagnostic criterion for asphyxial type of drowning in experimental studies.

Avalanche fatalities in Czech Republic: a 23-years retrospective study.

Avalanche fatalities are quite rare in the Czech Republic. Due to the presence of avalanche fields in the two Czech mountains, forensic pathologists at some forensic medicine departments may encounter this specific mechanism of accidental death. The authors summarize medicolegal aspects of deaths in avalanches in the territory of the Czech Republic for the twenty-three-year period between 1993-2015. Ten avalanche fatalities were recorded during study period. The studied group consisted of nine male and one female victims. The average age of the deceased was 27.9 years. Skiers or ski-alpinists died in the avalanche in five cases (50%), climbers in two cases (20%), snowboarders in one case (10%), cross-country skiers in one case (10%) and in one case it was a fatality of child playing on a snowy hill (10%). The cause of death was suffocation in four cases (40%), blunt trauma in four cases (40%), and in the remaining two cases it was the survival of trapped persons several hours after being rescued from the avalanche in the hospital; both victims subsequently died as a result of prolonged shock (20%) due to a combination of prolonged suffocation and hypothermia. The time interval from the fall of the avalanche to the rescue of the trapped person was in the range of minutes to 3 hours. The presence of alcohol or drugs was not detected in any studied case.

Positional asphyxia: accidental death due to head-down position in a badger sett.

Death from positional asphyxia occurs when the victim is found in a position that interferes with adequate breathing. We present an unusual case of a 67-yearold man who was found deceased trapped in a badger sett. The autopsy revealed marked congestion, cyanosis and a multitude of pinpoint hemorrhages in the face, neck and upper chest. Confluent scleral and conjunctival hemorrhage were observed and numerous petechial bleedings were found in the oral mucosa and within the reflected scalp. Death was attributed to positional asphyxia due to head-down position in a badger sett.

Asphyxia with a blunt instrument: which forensic evidence to use in complex cases of murder.

Background: The blunt injuries may be heterogeneous. Due to the diversity, it is often difficult to establish the type of weapon used. Particular attention must be paid to the circumstantial data and previous diseases because the injuries often could not correspond to the presumed instruments used. Case Report: A man was found dead in his bedroom wearing pajamas. On the bed there was a blanket with visible traces of blood, which had dried. There were around 10 dogs in the house, poor hygienic and sanitary conditions, widespread excrements and unbreathable air. Testimonies from general practitioner, neighbors and the partner were collected. An autopsy, histological and toxicological examination was performed. On external examination the face showed blood smearing down the nose, subconjunctival hemorrhages, and labial cyanosis. Mo-reover, a hypochromic skin area was present on the right lateral region of the neck. The inguinal region showed large de-epithelized areas with multiple purplish red ecchymoses which were histologically analyzed. These areas showed hemorrhagic infiltration in the superficial and deep dermis up to the adipose tissue due to traumatic action. Conclusion: The reconstruction of the case allowed us to state a strangulation probably attributable to a belt. The discovery of intradermal hemorrhagic infiltrations, supported by histopathological investigations, confirmed the diagnosis of blunt force injuries, excluding other type of non-violent causes of lesions. Therefore, we recommended the use of experimental methods and procedures to evaluate the harmful suitability on biological matrices.

An unusual case of homicide-suicide: overkilling by stabbing and suicide by hanging.

Background: This case presents a detailed forensic examination of a unique femicide case followed by the perpetrator's suicide. Case report: On a Sunday afternoon, a 52 year old man killed his 43 year old partner in their home with eleven stab wounds. A few minutes later, he committed suicide by suspending himself to a tree in their home garden by means of a rope. This unique case is interesting because of the combination of methods used for both homicide and suicide, as well as the relationship dynamics between the victim and perpetrator. The perpetrator committed homicide by stabbing and then hanged himself. Conclusion: The case adds valuable knowledge to Forensic Medicine, advocating for increased awareness and preventive measures against domestic and gender-based violence. This report provides an in-depth analysis of a homicide-suicide incident, focusing on a unique case of homicide-suicide. It serves to highlight the global crisis of femicide. The case is situated within the context of gender- based violence, illustrating how such acts are deeply rooted in societal norms. It highlights patterns of intimate partner violence, where emotional factors play a significant role. Forensic analysis uncovered the overkill nature of the homicide, indicating excessive injuries beyond what was necessary for death, reflecting the psychological turmoil of the perpetrator. It emphasizes the importance of identifying signs of potential violence in domestic settings and implementing interventions for mental health support and the prevention of genderbased violence.

When fire burns the evidence - Lesson 1: It is not always what it seems.

When a charred corpse is found, a primary unavoidable phase of the subject's identification is performed. Then, the medico-legal investigation must clarify whether the charring occurred before or after death, and so establish a differential diagnosis between accidental, homicidal, or suicidal modality. We report three cases of charred corpses in which a death dynamic was initially suspected but subsequently disproved: a suicidal intoxication in arson at first thought to be homicidal strangulation, a suicidal hanging revealed by neck haemorrhages in a suspected accidental fire, a femicide through ligature strangulation concealed with the simulation of a car accident. Many of the events are accidental, related to fires or traffic accidents. However, it must be considered that charring following a murder was deliberately provoked to prevent the identification of the subject and to conceal evidence of how the murder occurred. Because of the complex operational conditions in the study of a charred corpse, all the diagnostic tools proper to forensic science should be held beyond the preliminary circumstantial suggestions. We aim to emphasise the importance of a multidisciplinary approach since the solution of the three cases was possible thanks to the combination of crime scene investigation, radiological exams, autopsy, and histopathological and genetic analysis.

"When something goes wrong".

Background: Aspiration of food or liquids can result in suffocation, evolving in coughing, difficulty breathing and forced exhalation. Asphyxia occurs when the aspirated material occludes the upper airways, either in the proximal or distal tract, resulting in the inability to breathe. The risk of asphyxiation death, is increased if a person makes sudden movements while eating, walks or runs while eating, or even becomes distracted or frightened. It is higher in individuals with neurological diseases, intellectual disability (ID), cognitive impairment, psychiatric pathologies or their pharmacological treatments and people carrying additional physiological impairments, which can cause oral dysfunction and dysphagia. Protective mechanisms may sometimes lack or fail to expel food fragments stuck in the airways, which completely obstruct them. Case series: The authors present some peculiar cases of subjects who died from food bolus choking, namely a case of mozzarella-cheese clogging in a young subject (25 years old) undergoing rehabilitation treatment following a stroke; a 38-year-old man with middle-grade mental retardation died from first airway food bolus (mush of bread) clogging; a 26-year-old subject with epilepsy died from tripe clogging in the course of a seizure; a 38-year-old subject in psychiatric treatment for depressive disorder who died from clogging with octopus tentacles. Conclusion: Food bolus clogging asphyctic deaths generally occur in subjects with psychic/neurological pathologies, resulting in altered deglutition mechanisms or lack of protective reflexes. Foodstuff, especially if large or viscous, obstruct the proximal or distal airways, leading to acute respiratory failure and death. Autopsy is diriment in ascertain the cause of death.

Supermarket shopping death: the role of forensic investigations in plastic bag suffocation.

Background: Plastic bag suffocation may represent a very complex enigma for the forensic pathologist. The aim of this work is to highlight how the resolution of plastic bag suffocation cases is possible through the use of various forensic investigations, including psychological one (psychological autopsy) and toxicological examinations, in order to be able to define the manner of death. Case report: A 70-year-old man was found by his daughter lying on the bed, with his head inside a plastic bag knotted around his neck. The daughter claimed to have immediately removed the bag, but the father was already dead. An autopsy was performed. The clinical history of the victim was analysed in search of reason that could lead to suicide. The statements of the people on the death scene were examined. Results were compared with the scientific literature: a literature review was performed on the search engine Pubmed, Scopus and Google Scholar using the keywords "plastic bag suffocation" and "death". The autopsy showed no typical signs of asphyxial death. Toxicological examinations revealed benzodiazepines in the urine. Investigations revealed that the victim had been suffering from severe depression. Conclusions: The literature review confirmed that the most used wrapper is the supermarket shopping bag. We emphasize that plastic bag suffocation is a very quick event that does not leave any evident sign: this rapidity does not allow to appreciate the typical elements of asphyxiated death (petechiae, cyanosis). It seems that the fatal mechanism is a cardio-inhibitory, rather than a hypoxic process.

Scuba diving-related fatalities in the Philippines from 2008 to 2022 as reported in online news media.

The present study aims to investigate the demographics and characteristics of scuba diving fatalities in the Philippines which can help in the identification of local trends and ultimately in the development of appropriate preventive measures. Data on scuba diving-related fatalities in the Philippines from 2008 to 2022 were manually retrieved from online news media sources. Information on age, sex, nationality, certification, purpose, and causative factors, whenever possible were collected and analysed. A total of 39 fatalities were identified having a median age of 43.5 (range 20-80). Majority of victims were males (n = 30), and of foreign ethnicity (n = 26). Asphyxia was identified as the possible disabling injury in almost half of the cases (n = 17). The causes of death based on autopsies were determined only for few cases which included drowning (n = 2), heart attack (n = 1), and traumatic injuries from a dynamite blast (n = 1). Potential vulnerable groups were identified to be the ageing population and foreign tourist divers. In the absence of an existing database, this preliminary report provides the best available evidence at this time concerning scuba diving fatalities in the Philippines.

Effect of dimethyl fumarate on mitochondrial metabolism in a pediatric porcine model of asphyxia-induced in-hospital cardiac arrest.

Neurological and cardiac injuries are significant contributors to morbidity and mortality following pediatric in-hospital cardiac arrest (IHCA). Preservation of mitochondrial function may be critical for reducing these injuries. Dimethyl fumarate (DMF) has shown potential to enhance mitochondrial content and reduce oxidative damage. To investigate the efficacy of DMF in mitigating mitochondrial injury in a pediatric porcine model of IHCA, toddler-aged piglets were subjected to asphyxia-induced CA, followed by ventricular fibrillation, high-quality cardiopulmonary resuscitation, and random assignment to receive either DMF (30 mg/kg) or placebo for four days. Sham animals underwent similar anesthesia protocols without CA. After four days, tissues were analyzed for mitochondrial markers. In the brain, untreated CA animals exhibited a reduced expression of proteins of the oxidative phosphorylation system (CI, CIV, CV) and decreased mitochondrial respiration (p < 0.001). Despite alterations in mitochondrial content and morphology in the myocardium, as assessed per transmission electron microscopy, mitochondrial function was unchanged. DMF treatment counteracted 25% of the proteomic changes induced by CA in the brain, and preserved mitochondrial structure in the myocardium. DMF demonstrates a potential therapeutic benefit in preserving mitochondrial integrity following asphyxia-induced IHCA. Further investigation is warranted to fully elucidate DMF's protective mechanisms and optimize its therapeutic application in post-arrest care.

Suicidal decapitation by hanging: A systematic review of the literature and comparison with case reports.

INTRODUCTION: Suicidal hanging resulting in decapitation is rarely documented. This discussion involves a case of a 35-year-old man found decapitated in his residence's garden. A systematic literature review on hanging-induced decapitation was conducted to comprehensively investigate and compare the case to existing literature. The study aims to identify frequently described post-mortem findings in cases of suicidal hanging leading to decapitation. CASE REPORT: A 35-year-old man was found decapitated in his garden, with a jute strap and chimney debris nearby. The cervical region was completely severed along the dorsoventral and craniocaudal plane, exposing internal structures. A ligature mark was present, along with Amussat's sign and Simon's bleeding. METHODS: The systematic review of the literature followed PRISMA standards, analyzing 3622 publications from Google Scholar, PubMed, and Scopus databases up to 2023. Inclusion criteria comprised cases of complete or incomplete decapitation resulting from hanging, available in full-text and written in English. RESULTS: 16 articles on hanging-induced decapitation met the selection criteria; 22 cases were analyzed. Studies, mostly from Europe, showed a mean victim age of 44.3, all male. Fall height ranged from 1 m to 18 m, with various suspension media. Most cases displayed complete decapitation, primarily between cervical vertebrae C1 and C3. Some cases noted collateral findings. CONCLUSIONS: Complete crime scene investigation and thorough post-mortem examination are crucial for reconstructing events, especially with confounding elements. Precise evidence collection and literature comparison are essential to understand the case and substantiate the forensic pathologist's hypothesis in court.

Ischemic Post-Conditioning in a Rat Model of Asphyxial Cardiac Arrest.

BACKGROUND: Ischemic post-conditioning (IPoC) has been shown to improve outcomes in limited pre-clinical models. As down-time is often unknown, this technique needs to be investigated over a range of scenarios. As this tool limits reperfusion injury, there may be limited benefit or even harm after short arrest and limited ischemia-reperfusion injury. METHODS: Eighteen male Wistar rats underwent 7 min of asphyxial arrest. Animals randomized to IPoC received a 20 s pause followed by 20 s of compressions, repeated four times, initiated 40 s into cardiopulmonary resuscitation. If return of spontaneous circulation (ROSC) was achieved, epinephrine was titrated to mean arterial pressure (MAP) of 70 mmHg. Data were analyzed using t-test or Mann-Whitney test. Significance set at p ≤ 0.05. RESULTS: The rate of ROSC was equivalent in both groups, 88%. There was no statistically significant difference in time to ROSC, epinephrine required post ROSC, carotid flow, or peak lactate at any timepoint. There was a significantly elevated MAP with IPoC, 90.7 mmHg (SD 13.9), as compared to standard CPR, 76.7 mmHg (8.5), 2 h after ROSC, p = 0.03. CONCLUSIONS: IPoC demonstrated no harm in a model of short arrest using a new arrest etiology for CPR based IPoC intervention in a rat model.

The Effect of the COVID-19 Pandemic on Suicide Trends in Pretoria, South Africa.

ABSTRACT: Suicide is one of the worldwide leading causes of unnatural death. Pretoria is a capital city of South Africa and is the fourth most populated city in South Africa. Between 16 and 22 suicide cases are recorded daily in South Africa.Case files from the Pretoria Medico-Legal Laboratory were reviewed between 1 January 2015 to 31 December 2021, which spanned the COVID-19 pandemic. All cases of possible and probable suicides were included. One-way analysis of variance and Pearson chi 2 tests were conducted to determine statistical significance in the observed trends.A total of 1820 possible and probable suicide cases were identified. The year following the outbreak of the COVID-19 pandemic accounted for the largest number of suicides. White males were the most heavily represented population, followed by Black males. Hanging was the most common method for males, whereas poisoning via ingestion and/or overdose was more commonly used by females.Suicides in Pretoria have increased since previous studies from 9.74% and 10.2% to 13.32%. Methods used have changed among various population groups over the past two decades. This paper examined changes in suicide trends in Pretoria compared to previous studies and highlighted correlations between suicide trends and COVID-19 lockdown measures.

A Possible Mechanism of Laryngohyoid Fractures in Hanging: A Preliminary Observation.

ABSTRACT: Fractures of the hyoid bone, particularly the greater horns, and thyroid cartilage (superior horns) are known to be associated with hanging deaths. Depending on the literature, the frequency of these fractures varies from 0% to 83%. The mechanism underlying these fractures is believed to be direct compression or indirect traction from the ligature. The relationship of these structures with the cervical spine cannot be visualized with traditional internal examination, due to obstruction by surrounding soft tissue. Postmortem computed tomography scan offers an unobscured view of the relationship of the laryngohyoid structures with the cervical spine.We aim to illustrate the phenomenon of displacement of the laryngohyoid structures associated with fractures of the horns. In our case reports, the laryngohyoid structures were displaced, not only superiorly and posteriorly, but also in 2 of the cases, by tilting, when the suspension point was at the posterior or posterolateral aspect of the neck. This displacement had caused the greater horns of the hyoid bone and superior horns of the thyroid cartilage to be approximated against the cervical spine, particularly the transverse processes. We believe that, in these circumstances, the fractures were caused by pressure of the horns of the laryngohyoid structures against the cervical spine.

Promoting Safe Sleep: The Role of Doulas in Black Communities.

BACKGROUND: Accidental suffocation and strangulation in bed continues to be a critical issue in Black communities, despite the widespread initiatives to promote safe sleep. Doulas are in an ideal position to promote safe sleep, particularly in hard-to-reach communities that are more distrusting of conventional medical providers. Little is known about their practices and perspectives for putting infants down to rest. This study informs this gap in the literature. PURPOSE: The purpose of this study was to explore doulas' perspectives and practices in the field of putting infants down to sleep. The researchers aimed to determine whether Black caregivers that work with doulas are likely to encounter safe sleep education. METHODS: The researchers used a descriptive approach to inquiry. They conducted three focus groups with a total of 17 Black doulas. The researchers independently and critically reviewed the transcriptions and observation notes from each group to identify codes. They then triangulated the results using Artificial Intelligence-driven tools. FINDINGS: The study found four themes: (1) Individualized Services, (2) Cultural Sensitivity, (3) Negotiating Safety, and (4) Safe Sleep Education. CONCLUSIONS: The study concluded doulas have a commitment to promoting safe sleep. The researchers found that doulas engage in practices that help caregivers to integrate safe sleep practices into their lifestyle and to adapt them to meet their needs. The researchers also documented a desire for more information and instruction on safe sleep among practicing doulas.

Recognising and responding to non-fatal strangulation in domestic abuse.

Victims/survivors (the authors use this term throughout the article but acknowledge that individuals may use various terms to describe their experiences) of non-fatal strangulation associated with domestic abuse are at risk of further serious harm or death, but often do not disclose the assault. In addition, some of the signs and symptoms are not immediately apparent or obvious. Nurses have a professional responsibility to respond to suspicions about and/or disclosure of any type of domestic abuse by initiating safeguarding and protection procedures and must provide effective care. This article discusses non-fatal strangulation in domestic abuse, including the presenting signs and symptoms and barriers to disclosure, and describes the role of the nurse. The authors include a fictional case study to demonstrate the type of situation nurses may experience when they encounter a victim/survivor of non-fatal strangulation.

8-oxoguanine DNA glycosylase-1 may serve as biomarker of mechanical asphyxia.

AIM: To identify mtDNA and OGG1 as potential biomarker candidates for mechanical asphyxia. METHOD: The human tissues are divided into experimental group (hanging and strangulation) and control groups (hemorrhagic shock, brain injury group, and poisoning group). Detected the expression of OGG1 and integrity of mtDNA in cardiac tissue of each group. We used over-OGG1 vector and siRNA-OGG1 transfecting H9C2 cell line to observe the function of OGG1 in hypoxic cells. RESULTS: 1. mtDNA integrity decreased in the mechanical asphyxia group, OGG1 expression increased in mechanical asphyxia groups. They can be biomarkers for mechanical asphyxia. 2. OGG1 increased first and decreased in hypoxia-induced H9C2 cells. OGG1 upregulated the TFAM, NRF1, and Bcl2 in hypoxia-induced H9C2. OGG1 downregulated cleaved-Caspase3 in hypoxia-induced H9C2 cells. 3. In the normoxia condition, NAC maintained mtDNA integrity and decreased the mitochondrial membrane potential and amount of ATP. CONCLUSION: mtDNA integrity and OGG1 expression can be biomarkers for mechanical asphyxia. OGG1 can maintain mtDNA integrity and maintain the stability of the mitochondrial membrane.

To investigate the pattern of neck injuries and the role of toxicology in cases of hanging and manual/homicidal ligature strangulation in Ireland between 2016 - 2020: A retrospective review and analysis.

The pattern of neck injuries sustained in fatal cases of external compression to the neck is recorded during Post Mortem Examinations (PME), to assist in the interpretation of the circumstances that led to death. In this study, the PMEs performed for 298 cases of hanging and strangulation occurring between 2016 and 2020 in Ireland were retrospectively reviewed for the purpose of recording and collating the external and internal neck injuries observed during each PME, as well as the toxicology results for each decedent. Statistical analysis was performed to investigate potential novel associations between anthropometric variables pertaining to the decedents and the PME findings in cases of hanging and strangulation, serving to add further data to the existing body of research in this area and to assist in the resolution of future cases of hanging or strangulation where there are conflicting findings. In completing statistical analysis, it was found that there was no discernible association between the occurrences of cartilaginous neck fractures (CNFs) with increasing ligature width. Positive associations between increasing weight and BMI of the decedents were identified, and a significantly positive association between the increasing height of the decedent and the incidence of CNFs were identified. Analysis of the toxicology demonstrated that antipsychotics were implicated most frequently in cases of incomplete and complete hanging associated with CNFs and that opioids were implicated most frequently in cases of manual and ligature strangulation associated with CNFs. OBJECTIVE: To record the pattern of neck injuries sustained in retrospective cases of hanging and manual/ligature strangulation and to collate these findings so as to provide scientific evidence to support the interpretation of the findings in future cases of suicidal hanging and homicidal manual/ligature strangulation for the purpose of medicolegal investigation. To analyse the associations between the occurrence of neck fractures and anthropometric variables pertaining to the victims in cases of complete hanging. STUDY DESIGN: The reports of 298 Post Mortem Examinations (PMEs) performed for cases of hanging and manual/homicidal ligature strangulation between 2016 and 2020 in Ireland were retrospectively reviewed. Pseudoanonymised data sets were recorded for each report, which included the following parameters: neck injuries (soft tissue and cartilaginous), weight, height, BMI and ligature width, toxicology, noose position, ligature material, tongue protrusion, sex and age. Permission for the use of this data was sought from the pathologists and coroners involved in these cases. The data was analysed according to descriptive statistical methods and logistic regression analysis. RESULTS: Logistic regression analysis was undertaken to examine the associations between unit increases in ligature width and increases in a set of physical characteristics of the decedents (weight, BMI and height) with the occurrence of CNFs. Increasing ligature width was not found to increase the likelihood of a CNF occurring, where the Odds Ratio (OR) for this event occurring was 0.9596. Unit increases in body weight and BMI were found to increase the likelihood of the occurrence of a CNF with ORs of 1.0166 and 1.0607 respectively. Increasing height of the decedent yielded an OR = 4.64, demonstrating that CNFs are significantly more likely to occur with increasing height (CI 95 %: 0.2915, 73.9559). CONCLUSIONS: According to the statistical analysis performed for this study, increasing weight, height and BMI are parameters of the decedents which increase the likelihood of the occurrence of CNFs in cases of complete hanging.

Suicide mortality according to occupation and method of suicide, Massachusetts, 2010-2019.

BACKGROUND: Suicide rates in the United States have been increasing. Work-related factors may contribute to risk for suicide. These work-related factors may be reflected in a varied risk for different suicide methods between occupations. This study sought to assess occupational differences in suicide rates according to the method used. METHODS: Death certificate data about suicide deaths in Massachusetts between 2010 and 2019 were used to calculate mortality rates and rate ratios with univariable and multivariable models controlling for age, sex, race ethnicity, and educational attainment for suicides overall, and for three specific methods of suicide (hanging/strangulation/suffocation, firearms, and poisoning) by occupation. RESULTS: In multivariate models, the risk for suicide was significantly elevated for workers in arts, design, entertainment, sports, and media (relative risk [RR] = 1.84, 95% confidence interval [CI] = 1.53, 2.22); construction trades (RR = 1.68, 95% CI = 1.53, 1.84); protective services (RR = 1.49, 95% CI = 1.26, 1.77); and healthcare support occupations (RR = 1.55, 95% CI = 1.25, 1.93). Occupational risk for suicide differed across different methods. For hanging/strangulation/suffocation, workers in arts, design, entertainment, sports, and media occupations had the highest RR (2.09, 95% CI = 1.61, 2.71). For firearms, workers in protective service occupations had the highest RR (4.20, 95% CI = 3.30, 5.34). For poisoning, workers in life, physical, and social science occupations had the highest RR (2.32, 95% CI = 1.49, 3.60). CONCLUSIONS: These findings are useful for identifying vulnerable working populations for suicide. Additionally, some of the occupational differences in the risk for suicide and for specific methods of suicide may be due to workplace factors. Further research is needed to understand these workplace factors so that interventions can be designed for prevention.

Quantitative determination of nitrous oxide in human blood by HS-GC-MS: forensic application of two fatal poisoning cases.

Nitrous oxide (N2O), also known as laughing gas, has a euphoric effect and is becoming increasingly popular as a recreational inhalant drug. Deaths caused by recreational nitrous oxide abuse are rare, but may still occur. Although some methods for the quantification of N2O by GC-MS have been reported, elimination of carbon dioxide interference and the choice of a suitable internal standard remain current limitations to accurate N2O quantification. Here, a validated method using headspace-gas chromatography-mass spectrometry (HS-GC-MS) is described that allows the quantification of N2O in human blood samples: sodium hydroxide is used to remove carbon dioxide, and n-pentane is chosen as a suitable internal standard. Collectively, the validation results show a good linear relationship of N2O in blood within the concentration range of 0.02 ∼ 0.5 mL/mL and an LOD of 0.005 mL/mL. Subsequent application of the validated method to two real mortality cases due to N2O intoxication provided reference values for blood concentrations in forensic cases. Other biological specimens (gaseous samples and tissues) of the deceased were also analyzed to demonstrate that the deaths were caused by asphyxia due to the inhalation of N2O.