Suicide by plastic bag suffocation combined with the mixture of citric acid and baking soda in an adolescent.

We describe a case of suicidal asphyxiation using a plastic bag combined with carbon dioxide (CO2) gas. A 20-year-old male, whose head was covered with a plastic bag, was found dead in his room. In the plastic bag, there were two glass-made cups containing liquid-like substance. Through crime scene investigation by police staffs, a bottle of citric acid and a box of baking soda were also discovered in his room. The forensic autopsy revealed that there were neither lesions nor injuries in all of the organs. Moreover, any drugs and poisons could not be detected in blood samples. Based on autopsy findings and crime scene investigation, the cause of death was diagnosed as acute asphyxia due to CO2 intoxication by the mixture of citric acid with baking soda in the plastic bag. To the best of our knowledge, there are no medical literatures describing plastic bag suffocation combined with CO2 gas generated from citric acid and baking soda, which has been widely distributed as suicidal means through websites. This case report promotes forensic pathologists and medical coroners to emphasize that the Internet has a crucial role on a source of suicidal information or a promoter of suicide all over the world.

Potential medical adverse events associated with death: a forensic pathology perspective.

OBJECTIVE: To determine the incidence of potential medical adverse events among patients undergoing forensic autopsy, and to present the characteristics of potential medical adverse events. DESIGN: Retrospective review of consecutive autopsy records. SETTING: Department of Forensic Medicine, the Jikei University School of Medicine, Tokyo, Japan. PARTICIPANTS: A total of 3355 forensic autopsy cases between 1983 and 2006. MAIN OUTCOME MEASURES: Incidence of potential medical adverse events identified in decedents undergoing forensic autopsy, classified by actual occurrence as 'confirmed', 'equivocal' and 'negative' cases; proportion of potential diagnostic, performance and system errors among potential medical adverse events. RESULTS: Of 291 autopsies (8.7%) with potential medical adverse events, 66 cases (22.7%) were confirmed, 42 cases (14.4%) were negative and 183 cases (62.9%) were equivocal. Confirmed cases consisted of potential diagnostic errors in 49 cases (74.2%) and performance errors in 17 cases (25.8%). Equivocal cases included 99 cases associated with potential diagnostic errors (54.1%) and 60 cases associated with potential system errors (32.8%). In 38 of the confirmed cases (57.5%), serious exacerbation of patient condition occurred outside the medical facility. CONCLUSIONS: Potential medical adverse events are not uncommon in decedents undergoing forensic autopsy. They are particularly associated with potential diagnostic errors. Forensic autopsy may provide information that could be used to improve care and reduce deaths due to potential medical adverse events.

Intracranial vertebral artery dissection resulting in fatal subarachnoid hemorrhage: clinical and histopathological investigations from a medicolegal perspective.

OBJECT: Subarachnoid hemorrhage (SAH) due to a ruptured intracranial vertebral artery (VA) dissection sometimes results in a sudden fatal outcome. The authors analyzed the relationship between clinical features and histopathological characteristics among fatal cases to establish valuable information for clinical diagnostics and prophylaxis. METHODS: This study included 58 medicolegal autopsy cases of ruptured intracranial VA dissection among 553 fatal nontraumatic cases of SAH that occurred between January 2000 and December 2007. Their clinical features were obtained from autopsy records. Histopathological investigations were performed on cross-sections obtained from all 4-mm segments of whole bilateral intracranial VAs and prepared with H & E and elastica van Gieson staining. RESULTS: The autopsy cases included 47 males and 11 females, showing a marked predilection for males. The mean age was 46.8 +/- 7.7 years, with 78% of the patients in their 40s or 50s. Hypertension was the most frequently encountered history; it was found in 36% of cases from clinical history and in 55% of cases based on autopsy findings. Prodromal symptoms related to intracranial VA dissections were detected in 43% of patients. Headache or neck pain lasting hours to weeks was a frequent complaint. Of patients with prodromal symptoms, 44% had consulted doctors; however, in none of these was SAH or intracranial VA dissection diagnosed at a preventable stage. Autopsy revealed fusiform aneurysms with medial dissecting hematomas. Apart from ruptured intracranial VA dissection, previous intracranial VA dissection was detected in 25 cases (43%); among them, 10 showed previous dissection of the bilateral intracranial VAs. The incidence of prodromal symptoms (60%) among the patients with previous intracranial VA dissection was significantly higher than that (30%) among cases without previous dissection (chi-square test; p = 0.023). Most previous intracranial VA dissections formed a single lumen resembling nonspecific atherosclerotic lesions, with the exception of 3 cases (12%) with a double lumen. CONCLUSIONS: Intracranial VA dissection resulting in fatal SAH frequently affects middle-aged men with untreated hypertension. Related to the high frequency of prodromal symptoms, latent previous intracranial VA dissection was histopathologically detected. Furthermore, intracranial VA dissection tends to induce multiple lesions affecting both intracranial VAs recurrently. This suggests the importance of an awareness of sustained whole intracranial VA vulnerability for the prevention of recurrence. The incidence of prodromal symptoms was significantly higher among patients with previous intracranial VA dissections. Thus, earlier diagnosis of intracranial VA dissections at the unruptured stage is desirable for prophylaxis against fatal SAH.

Risk factors, diagnosis and prevention of sudden unexpected infant death.

The diagnosis of the cause of sudden unexpected infant death (SUID) is often difficult work for forensic pathologists. Its misdiagnosis or misclassification is the cause of crucial epidemiological and medicolegal problems. During the sudden infant death syndrome (SIDS) epidemic, many reports described the risk factors of SIDS as well as mechanical suffocation during sleep. Meadow's report has invited worldwide debate over whether the cause of SUID is attributable to SIDS or suffocation. On the basis of this background, the problems concerning causal diagnosis and risk factors, particularly the accidental suffocation of infants during sleep, and the specific pattern of suffocation, was reviewed from the forensic pathological viewpoint. The following tasks remain to be done for the future: (1) to avoid preventable SUIDs, the most effective measure worldwide is to identify high-risk factors for all SUIDs, including SIDS, accidental suffocation and undetermined causes, and then transmit this information to the public. (2) SIDS should be uniformly defined and diagnosed as strictly as possible to gain its reliability in the public health community and in a legal framework.

Trends in early and late deaths due to motor vehicle accidents in Japan.

To clarify trends and urban-rural differences in the early death rate (deaths within 24 h divided by the deaths within 1 year after motor vehicle accident x100 [%]) due to motor vehicle accidents (MVAs) in Japan. Mortality data were collected from the annual statistics of traffic accident research and vital statistics in Japan from 1980 through 1998 and analyzed. Early death rates were nearly constant (73.9-78.0%) from 1980 through 1998. Early death rates were lower in younger and elderly groups. As regards to geographic variations, early death rates and 1-year death rates per 100,000 vehicles were significantly higher in rural areas (population density <1000/km(2)) than in urban areas. To investigate MVA deaths, both early and late deaths should be examined. Decreasing the early death rate, a new index for MVA death, which reflects the reduction of injury severity is important for preventing MVA deaths.

Prediction of injuries to the heart and thoracic aorta in unrestrained drivers.

The purpose of the study was to investigate factors predicting injuries to the heart and/or thoracic aorta (H/TA) of unrestrained drivers in frontal motor vehicle collisions. We retrospectively analyzed findings of forensic autopsies of 37 unrestrained drivers of automobiles without airbags involved in frontal collisions. Mechanisms of injury, injury severity, presence of major injuries, and the number of fractured ribs were examined in each case. Victims were subdivided for comparison into those with (19 cases) and without (18 cases) H/TA injuries. The injury severity score and the abbreviated injury scale of the chest were significantly higher in persons with H/TA injuries (65.3+/-15.7 and 5.4+/-0.9) than in persons without (31.6+/-22.0 and 1.8+/-1.9). Because univariate analysis showed that the presence of multiple fractured ribs was an important predictor of H/TA injuries, we examined the relation between H/TA injuries and the number of fractured ribs. Copas's nonparametric smooth binary regression model showed that H/TA injuries were more likely in persons with eight or more fractured ribs. The presence of eight or more fractured ribs predicts H/TA injuries in unrestrained drivers.

Age-associated decrease in 8-hydroxy-2'-deoxyguanosine (8-OHdG) immunoreactivity in the autopsied brain.

The 8-hydroxy-2'-deoxyguanosine (8-OHdG) is a DNA base modified by reactive oxygen species (NOS). The 8-OHdG has been shown to be generated in the brain during ischemia-reperfusion. We performed the immunohistochemical study of 8-OHdG in the brains of autopsied specimens. Age had a statistically significantly negative correlation with 8-OHdG immunoreactivity in glial cells. The 8-OHdG immunoreactivity in glial cells was not increased in the surrounding border of the infarction compared with the non-ischemic areas in the same cases. There was no statistically significant difference in the disease-free areas between infarction and the age-matched control cases. This indicates that 8-OHdG immunoreactivity may not be a sensitive tool to evaluate the infarction injury in human autopsied specimens.

Sudden death involving inhalation of 1,1-difluoroethane (HFC-152a) with spray cleaner: three case reports.

Spray cleaner is a cleaning product containing compressed 1,1-difluoroethane (HFC-152a) to blow dust off electric devices and other sensitive equipment; however, it is also inhaled to induce euphoria. This report describes three cases of death involving HFC-152a inhalation with spray cleaner under different circumstances. In case 1, death was during inhalation for euphoria with which led to having frostbite. In case 2, death may have been associated with suicidal intention. Case 3 was also considered an accidental autoerotic death. In all three cases, HFC-152a was detected at 99.2-136.2mg/l in blood samples, 94.5-191.9 mg/l in urine samples and 3.6-18.4 mg in the gastric contents according to gas chromatography with flame ionization detection. To prevent death associated with HFC-152a inhalation from spray cleaner, the danger of the sudden death should be announced to people, given the ready availability of commercial products containing HFC-152a.

Toxicological analysis of 17 autopsy cases of hydrogen sulfide poisoning resulting from the inhalation of intentionally generated hydrogen sulfide gas.

Although many cases of fatal hydrogen sulfide poisoning have been reported, in most of these cases, it resulted from the accidental inhalation of hydrogen sulfide gas. In recent years, we experienced 17 autopsy cases of fatal hydrogen sulfide poisoning due to the inhalation of intentionally generated hydrogen sulfide gas. In this study, the concentrations of sulfide and thiosulfate in blood, urine, cerebrospinal fluid and pleural effusion were examined using GC/MS. The sulfide concentrations were blood: 0.11-31.84, urine: 0.01-1.28, cerebrospinal fluid: 0.02-1.59 and pleural effusion: 2.00-8.59 (µg/ml), while the thiosulfate concentrations were blood: 0-0.648, urine: 0-2.669, cerebrospinal fluid: 0.004-0.314 and pleural effusion: 0.019-0.140 (µmol/ml). In previous reports, the blood concentration of thiosulfate was said to be higher than that of sulfide in hydrogen sulfide poisoning cases, although the latter was higher than the former in 8 of the 14 cases examined in this study. These results are believed to be strongly influenced by the atmospheric concentration of hydrogen sulfide the victims were exposed to and the time interval between exposure and death.

Segmental arterial mediolysis of varying phases affecting both the intra-abdominal and intracranial vertebral arteries: an autopsy case report.

We report an autopsy case of segmental arterial mediolysis (SAM) of various phases occurring in both the intracranial vertebral artery (IVA) and intra-abdominal arteries. The patient was a 70-year-old male found dead in his house. The cause of death was massive intra-abdominal hemorrhage owing to a ruptured right gastroepiploic artery. Histopathological examination revealed that there was a broad arterial dissection as long as 20 cm in the right gastroepiploic artery associated with SAM in the injurious phase. In addition, SAM in the reparative phase was observed as organized arterial dissections in the left gastric artery. Furthermore, SAM in the reparative phase was detected as an arterial dissection in the right IVA undergoing an organizing process. These three lesions were considered to have developed at different times. SAM occurring in both the intra-abdominal and intracranial vertebral arteries is extremely rare. This coincidence may provide a clue to the relationship between SAM and spontaneous IVA dissection.

Differential diagnosis between traumatic and nontraumatic rupture of the intracranial vertebral artery in medicolegal autopsy.

We attempted to establish histopathological identification between traumatic rupture and nontraumatic arterial dissection of the intracranial vertebral artery (IVA) resulting in subarachnoid hemorrhage (SAH). Step-serial observations of ruptured IVAs among four traumatic and 44 nontraumatic SAH patients were investigated. We found that the most specific characteristic for differentiation was the shape of the ruptured adventitia. Extension of the adventitia was clearly observed in nontraumatic cases. In contrast, traumatic cases showed transmural ruptures. Other specific characteristics were also detected. For traumatic cases, small incomplete tears of intima and media were frequently found; they formed oblique tears without adventitial extension. Fragmentized internal elastic lamina was also observed in traumatic cases. In contrast, previous arterial dissections were frequently confirmed in nontraumatic cases. Medial degenerations or defects were detected in all nontraumatic cases. In these cases, the peripheral lesion of the rupture was appeared as intimal tears at recessed vascular wall caused by medial defects. This suggested a relationship between medial lesions and pathogenesis of arterial dissections. These additional features were found in both ruptured and non-ruptured intracranial arteries. We concluded that histopathological investigation is a reliable method for differential diagnosis between traumatic and nontraumatic rupture of the IVA resulting in fatal SAH. These morphological differentiations could be valuable for medicolegal diagnosis.

Fatal vascular injury as a result of operations: experience of two surgery-related autopsies.

We experienced two autopsy cases of unexpected death during surgical operation. Case 1 was a 60-year-old male. Salvage esophagectomy was performed from the right side of the thrax. After dissection of the lymph node, blood pressure decreased suddenly. Emergency thoracotomy was done for diffuse hemothorax in the left thoracic cavity. The patient died despite aggressive hemostasis. Autopsy findings revealed that the operator dissected the left subclavian artery instead of the lymph nodes. Case 2 was a 60-year-old male with advanced thyroid cancer with pelvic metastasis. Surgical removal of the sacrum was attempted for pain relief. The operation was interrupted because of massive hemorrhage from the iliac veins. After the operation, the patient's left leg quickly became necrotic. Despite the bypass grafting from the right to the left femoral artery, the patient died of reperfusion injury. Autopsy revealed ligation of the left common iliac artery along with the accompanying vein. The leg necrosis was thought to have resulted from the vascular ligation. In these two cases, the demonstration and elucidation of the causes of deaths were required with medicolegal autopsies. However, it proved difficult to visualize the operated vessels in detail. In autopsy investigations related to surgical operations, detailed information of the clinical course is valuable and should be provided by the operators themselves, as well as being obtained from clinical charts.

Sudden death due to undiagnosed acute promyelocytic leukemia: a case report.

Acute promyelocytic leukemia (APL) is associated with severe hemorrhagic coagulopathy induced by the release of procoagulant, plasminogen, and protease from leukemic cells. The case described in this report is of a 15-year-old male who unexpectedly died due to a cerebral hemorrhage caused by underlying APL within 12 h after presentation. This case suggests that underlying APL should be considered as a differential diagnosis when sudden death occurs with a fatal spontaneous hemorrhage, although it is rare.

Analysis of fatal injuries to motorcyclists by helmet type.

To clarify the characteristics of injuries of motorcyclists dying in accidents in relation to helmet type, we retrospectively analyzed forensic autopsies of 36 helmeted motorcycle riders. The presence of major injuries and injury severity were evaluated with the injury severity score and the 1990 revision of the Abbreviated Injury Scale. Persons with open-face helmets (19 cases) were significantly more likely to have sustained severe head and neck injuries, especially brain contusions, than were persons with full-face helmets (17 cases). Furthermore, major injuries of the chest or abdomen, rib fractures, lung injuries, and liver injuries were each present in more than one quarter of all cases (26.3% to 70.6%), but their prevalences did not differ significantly between riders with different types of helmet. Because many types of head and neck injuries cannot be prevented and fatal chest and abdominal injuries occur despite the use of full-face helmets, more effective helmets and devices for protecting the chest and abdomen are needed to decrease deaths from motorcycle accidents.