Determination of Electrocution Using Fourier Transform Infrared Microspectroscopy and Machine Learning Algorithm / 法医学杂志

Objective To analyze the differences among electrical damage, burns and abrasions in pig skin using Fourier transform infrared microspectroscopy （FTIR-MSP） combined with machine learning algorithm, to construct three kinds of skin injury determination models and select characteristic markers of electric injuries, in order to provide a new method for skin electric mark identification. Methods Models of electrical damage, burns and abrasions in pig skin were established. Morphological changes of different injuries were examined using traditional HE staining. The FTIR-MSP was used to detect the epidermal cell spectrum. Principal component method and partial least squares method were used to analyze the injury classification. Linear discriminant and support vector machine were used to construct the classification model, and factor loading was used to select the characteristic markers. Results Compared with the control group, the epidermal cells of the electrical damage group, burn group and abrasion group showed polarization, which was more obvious in the electrical damage group and burn group. Different types of damage was distinguished by principal component and partial least squares method. Linear discriminant and support vector machine models could effectively diagnose different damages. The absorption peaks at 2 923 cm-1, 2 854 cm-1, 1 623 cm-1, and 1 535 cm-1 showed significant differences in different injury groups. The peak intensity of electrical injury's 2 923 cm-1 absorption peak was the highest. Conclusion FTIR-MSP combined with machine learning algorithm provides a new technique to diagnose skin electrical damage and identification electrocution.

Metabolomics Changes of Serum in Rats Dying from Untypical Electric Injury / 法医学杂志

Objective To study the differential metabolites of serum in rats dying from untypical electric injury by 1H nuclear magnetic resonance （1 NMR）-based metabolomics methods, in order to provide clues for identification of death from antemortem untypical electric injury and instant postmortem electric injury. Methods Models of rats dying from untypical electric injury, instant postmortem electric injury, mechanical asphyxia, mechanical injury, and high temperature injury were established. The rats in control group were executed without any treatment. The serums of rats from every group were detected by 1H NMR-based metabolomics technology to screen differential metabolites. Results The rats dying from untypical electric injury group was compared with those from mechanical asphyxia group, mechanical injury group, high temperature injury group, and control group, respectively. Four chemical shift points with diagnostic value, and their corresponding metabolites were screened. These chemical shift points contained many small molecules, such as alcohols, phenols, sugars, amino acids, etc. The death from untypical electric injury group was compared with those from instant postmortem electric injury group and control group, and then eight chemical shift points with diagnostic value and their corresponding metabolites were screened. These chemical shift points contained small molecules, such as sugars, amino acids, esters, nucleic acids, etc. Conclusion The 1H NMR-based metabolomics technology can identify differential metabolites of serum in rats dying from untypical electric injury, therefore it may provide a basis for the diagnosis of death from untypical electric injury and the identification of antemortem electric injury and instant postmortem electric injury.

Analysis of 4 Cases of Electrocution due to Direct Current Electronic Hunter / 法医学杂志

Objective To summarize the characteristics of cases of electrocution due to direct current （DC） electronic hunter, and to provide references for forensic identification. Methods Four cases of electrocution due to DC electronic hunter were collected. Statistical analysis was carried out from the perspective of the scene and electric marks distribution, damage characteristics and histopathological changes. Results All the 4 cases of electrocution were accidental events. There were multiple electric marks, most of which were located in the lower limbs with serious damage. Some strip type electric marks were visible. Conclusion The distribution, morphological characteristics and severity of the electric marks caused by DC electronic hunter are different from those of the ordinary low-voltage alternating current damage. It is alerting that there would be actions of destroying the scene and abandoning the corpse in such cases.

Application of soft tissue expander in plastic reconstruction of head / 中国基层医药

Objective To explore the timing of surgical operation and surgical incision for the treatment of head of electrical injury and scarred alopecia with soft tissue expander .Methods Twenty-three patients with high tension electrical injury and scarred alopecia were collected ,the soft tissue expander was used to repair the wound and scar area.Selected the expander to embed the incision:patients with scarred alopecia were selected to be near the hair area in the scar;high tension electrical injury in patients with incision location selection based on the time of injury and wound repair requirements vary;within 5 days after injury ,surgery incision can be selected from the wound about 2-3cm;more than 5 days after injury,the patients chose to stay away from the wound incision ,incision about 4-5cm. Results Of 23 patients,postoperative scalp expansion flap good blood supply ,a period to solve the high tension electrical injury caused by skull necrosis and scarred alopecia problems .The patients according to the wound debride-ment and repair requirements using different surgical incision for dilator implantation ,wound and flap infection ,dilated flap poor blood supply ,necrosis,dilator exposed and other issues did not occur after surgery .Conclusion Flexible use of expander embedded surgical incision can be more effectively adapted to the wound repair requirements ,timely reduction of implantation expander surgery when the difficulty of stripping ,shorten the operation time,the maximum possible protection of healthy scalp tissue ,and eventually get a satisfactory clinical cosmetic repair effect .

Infrared Spectral Characteristics of Electrical Injuries on Swine Skin Caused by Different Voltages Based on Machine Learning Algorithms / 法医学杂志

Objective To explore infrared spectrum characteristics of different voltages induced electrical injuries on swine skin by using Fourier transform infrared-microspectroscopy (FTIR-MSP) combined with machine learning algorithms, thus to provide a reference to the identification of electrical skin injuries caused by different voltages.Methods Electrical skin injury model was established on swines.The skin was exposed to 110 V, 220 V and 380 V electric shock for 30 s and then samples were took, with normal skin tissues around the injuries as the control.Combined with the results of continuous section HE staining, the FTIR-MSP spectral data of the corresponding skin tissues were acquired.With the combination of machine learning algorithms such as principal component analysis (PCA) and partial least squares-discriminant analysis (PLS-DA), different spectral bands were selected (full band 4 000-1 000 cm-1and sub-bands 4 000-3 600 cm-1, 3 600-2 800 cm-1, 2 800-1 800 cm-1, and 1 800-1 000 cm-1), and various pretreatment methods were used such as orthogonal signal correction (OSC), standard normal variables (SNV), multivariate scatter correction (MSC), normalization, and smoothing.Thus, the model was optimized, and the classification effects were compared.Results Compared with simple spectrum analysis, PCA seemed to be better at distinguishing electrical shock groups from the control, but was not able to distinguish different voltages induced groups.PLS-DA based on the 3 600-2 800 cm-1band was used to identify the different voltages induced skin injuries.The OSC could further optimize the robustness of the 3 600-2 800 cm-1band model.Conclusion It is feasible to identify electrical skin injuries caused by different voltages by using FTIR-MSP technique along with machine learning algorithms.

Contribuição da autopsia médico-legal para a investigação do acidente de trabalho fatal: relato de caso / Contribution of medico-legal autopsy to the investigation of fatal occupational accidents: case report

Os acidentes de trabalho são um importante problema de saúde pública. Embora entendidos como eventos não intencionais, podem ser previsíveis e preveníveis. Os institutos médico-legais desempenham importante papel na investigação de acidentes de trabalho fatais (ATF), pois todos os casos de morte violenta ou suspeita devem ser submetidos à necropsia forense. Este trabalho é um relato de caso necroscópico de ATF em que os dados obtidos na necropsia poderão contribuir para a melhor compreensão da dinâmica do ocorrido. Tratava-se de indivíduo do sexo masculino, com 34 anos de idade e suspeita de ter sido vítima de queda em ambiente de trabalho. Havia equimoses avermelhadas e arroxeadas no tórax, nos membros superiores e na região occipital do periciado. Na epiderme dos dedos das mãos foram observadas lesões cutâneas endurecidas, com destacamento parcial, que apresentavam aspectos macro e microscópico característicos de passagem de corrente elétrica em vida. Evidenciou-se fratura de crânio nos ossos parietal esquerdo e occipital, hemorragia subaracnoidea difusa, além de petéquias laríngeas, subpleurais e subepicárdicas. A pesquisa de alcoolemia e o exame toxicológico foram negativos. A causa do óbito foi traumatismo cranioencefálico contuso, tendo sido observados no periciado indícios de contato com corrente elétrica em vida. A autopsia permitiu melhor entendimento do mecanismo de morte e eliminou a possibilidade do trabalhador estar sob efeito de substâncias psicoativas no momento da ocorrência. Isso pode ser importante para a determinação da sequência dos eventos, auxiliando na implantação de medidas de prevenção.

Work accidents are a major public health problem. Although they are understood to be unintentional events, they are both predictable and preventable. Medico-legal institutes play a key role in the investigation of fatal work-related accidents (FWRA) because all cases of violent or suspicious death must be subjected to forensic autopsy. The present is a report of a case of FWRA in which autopsy contributed to a better understanding of the event's dynamics. The case concerns a 34-year-old man believed to have suffered a fall at the workplace. Examination revealed reddish and purple bruises on the chest, upper limbs and the occipital area, and hardened, partially detached epidermal lesions on the fingers, with the characteristic macro- and microscopic appearance of passage of electric current while alive. Fractures on the left parietal and occipital bones were found, as well as diffuse traumatic subarachnoid hemorrhage and laryngeal, subpleural and subepicardial petechiae. Blood alcohol and toxicology tests were negative. The cause of death was blunt head trauma, with signs of contact with electric current while alive. The autopsy therefore allowed for a better understanding of the mechanism of death, and ruled out the possibility of the worker having been under the effect of psychoactive substances at the time of event. Autopsy might be relevant to determine the sequence of events, thus contributing to the implementation of preventive measures.

Extension of a Scapular Fracture into the Glenoid Cavity after Low-voltage Electric Shock

We, herein, present a patient with no history of trauma who developed shoulder pain after undergoing low-voltage electric shock. According to the computed tomography, there was a multi-segmental fracture that extended into the glenoid cavity of the left scapula. A good outcome was obtained after open reduction and internal fixation. Emergency physicians should be aware of the possibility of scapular fracture extending into the glenoid cavity, especially in patients with shoulder pain after electrical injury.

Medial Lemniscus Tract Lesion After High Voltage Electrical Injury: A Case Report

We present the case of a 33-year-old man who experienced a 10,000-V electrical shock when working with electrical wiring. He suffered third-degree burns on his scalp at the right occiput (entry wound) and on his left arm (exit would), and a second-degree burn on his left foot (exit wound). He presented with severe spasticity of both lower extremities, motor weakness with a Medical Research Council grade of 3, and sensory impairments below thoracic level 11 that included an inability to sense light touch and defects in proprioception. Initial magnetic resonance imaging (MRI) scans of his spine and brain showed no definite abnormalities. However, tractography obtained by diffusion tensor imaging of the brain showed absence of the right medial lemniscus tract. A cervical MRI scan 1 month later showed spinal cord swelling from cervical 1-5 levels, and signal changes in the lateral and posterior white matter in the axial view. After 6 months of rehabilitation, he recovered almost normal degree of motor function in his lower extremities and disappearance of spasticity. However, since the sensory impairments persisted, especially defects in proprioception, he was unable to walk independently.

A Case of Prehospital Ventricular Fibrillation due to Electrical Injury

These days, the frequency of electrical injuries is increasing with the increased spread of electricity use. Electrical injuries cause various complications, ranging from a local superficial skin injury to extensive internal organ damage, including essential vital organs, such as the cardiovascular or central nervous system. We encountered the patient who collapsed after an electrical injury on the scene and was resuscitated successfully after the prehospital early recognition of ventricular fibrillation, and rapid defibrillation, followed by post cardiac arrest care in the hospital. Prehospital early electrocardiogram monitoring and defibrillation may be needed in electrical injured patients.

Queimaduras domésticas na população infantojuvenil: atendimentos de urgência e emergência / Domestic burns among children, adolescents and young adults: urgency and emergency cases

Estudo cujo objetivo foi analisar as queimaduras domiciliares decorrentes de exposição à corrente elétrica/radiação/temperatura, fumaça/fogo/chamas e contato com fonte de calor/substâncias quentes, em vítimas crianças, adolescentes e jovens, atendidos em serviço de urgência/emergência de referência. Estudo descritivo, transversal, com vítimas de queimaduras domiciliares (entre zero a 24 anos) atendidas por serviço de pronto-atendimento em uma capital do centro oeste brasileiro, no ano de 2013. Foram estudadas 84 vítimas de queimaduras domiciliares, prevaleceu o sexo feminino (59,5%) e a faixa etária de 1-4 anos (27,4%). As queimaduras mais frequentes foram por contato com fonte de calor/substâncias quentes (82,1%) e exposição à fumaça/fogo/chamas (15,5%). As regiões corpóreas mais atingidas foram cabeça, tronco, membros superiores e inferiores (90,5%) e prevaleceu a queimadura de segundo grau (40,5%). Queimaduras domiciliares atingem significativamente o público infantojuvenil com destaque para o sexo feminino, apontando para a importância de atividades preventivas e educativas direcionadas para as meninas.

The objective of this study was to analyze domestic burns caused by the exposure to electric current/radiation/temperature, smoke/fire/flames and contact with a source of heat/hot substances, in children, adolescents and young adults treated at an urgency/emergency service of reference. A descriptive, cross-sectional study was conducted with victims (0 to 24 years of age) of home burns treated at an urgency/emergency service of a capital city located in the center-west region of Brazil, in 2013. In total, 84 victims of home burns were studied, with prevalence of female victims (59.5%) and age group of 1-4 years of age (27.4%). The most frequent burns were caused by contact with a source of heat/hot substances (82.1%) and exposure to smoke/fire/flames (15.5%). The body areas most commonly affected by home burns were head, trunk, and upper and lower limbs (90.5%), with prevalence of second-degree burns (40.5%). Home burns significantly affect children, adolescents and young adults, particularly female subjects, highlighting the importance of providing preventive and educational activities to female victims.

Cardiac Ultrastructure and Changes of HSP70 and HIF-1α Expression in Electric Shock Death Rats / 法医学杂志

Objective T o observe cardiac ultrastructure and the expression of heat shock protein 70 (H SP70) and hypoxia inducible factor-1α (H IF-1α) in electric shock death rats and to explore the application of these indexes as the basis of m edical identification in electric shock death. Methods Seventy-tw o SD rats w ere random ly divided into electric shock death group, postm ortem electric shock group and the control group. T he changes of m yocardial ultrastructure w ere observed by transm ission electron m icro-scope, and the expressions of m yocardial H SP70 and H IF-1α w ere observed by im m unohistochem ical technology. Results M yocardial m yofibril fracture, m itochondrial cristae and m em brane dissolution, and disordered arrangem ent of Z lines and M lines w ere observed in electric shock rats. H SP70 and H IF-1αw ere strong positive expressions in the electric shock death group, significantly com pared w ith the con-trol and postm ortem electric shock groups (P<0.05). Conclusion T he expressions of H SP70 and H IF-1αw ere obviously increased in electric shock death group, w hich m ay be used as the diagnostic indicator of electric shock death.

Changes of HCN4, Cx43 Expression in the Sinoatrial Node of Electric Shock Death / 法医学杂志

Objective T o investigate the expression of hyperpolarization-activated cyclic nucleotide-gated cation channel 4 (H C N 4) and connexin43 (C x43) in the sinoatrial node of electric shock death. Meth-ods As experim ental group, 34 cases of electric shock death who had definite current m ark evidence were selected from pathology departm ent of X uzhou M edical C ollege from 2010 to 2013. As the control group, 20 cases of fatal severe craniocerebral injury in traffic accidents were chosen. T he expressions of H C N 4 and C x43 in the sinoatrial node were observed by im m unohistochem ical technology. Results H C N 4 positive cells expressed in the cell m em brane and cytoplasm of the sinoatrial node. C x43 positive cells expressed in the cell m em brane and cytoplasm of T cells and m yocardial cells. T he expression of H C N 4 was significantly higher than that of the control group (P<0.05) and the expression of C x43 was signifi-cantly lower than that of the control group (P<0.05). Conclusion T he changes of H C N 4 and C x43 ex-pressions in the sinoatrial node illustrate electric shock death m ight be related to the abnorm alities of cardiac electrophysiology and conduction.

Therapeutic effect analysis of prehospital first aid in patients with cardiopulmonary arrest caused by e-lectrical shock / 心血管康复医学杂志

Objective:To explore clinical significance of prehospital first aid in treatment of patients with cardiopul-monary arrest caused by electrical shock.Methods:A total of 85 patients with cardiopulmonary arrest caused by e-lectrical shock,who hospitalized in our community health service center from Jul 2002 to Feb 2014,were selected. Influence of different factors of prehospital first aid on success rate of recovery and survival rate were explored.Re-sults:After prehospital first aid,heart beat and respiration recovered in 21 cases (24.7%)and 13 patients (15.3%) survived and discharged in 85 subjects.Success rate of recovery and survival rate on discharge in patients with age ≥60 years and high voltage wound were lower,but without significant difference compared with those of 0.05);for the time from electric shock to cardiopulmonary resuscitation,success rate of recovery and survival rate on discharge were the highest in 16min,P <0.05 or <0.01. Conclusion:Early prehospital first aids,such as cardiopulmonary resuscitation etc,can significantly improve progno-sis in patients with cardiopulmonary arrest caused by electrical shock.

Neurological Complication After Low-Voltage Electric Injury: A Case Report

Electrical shock can result in neurological complications, involving both peripheral and central nervous systems, which may present immediately or later on. However, delayed neurological complications caused by low-voltage electric shock are rarely reported. Here, a case of a man suffering from weakness and aphasia due to the delayed-onset of the peripheral nerve injury and ischemic stroke following an electrical shock is presented. Possible mechanisms underlying the neurological complications include thermal injury to perineural tissue, overactivity of the sympathetic nervous system, vascular injury, and histological or electrophysiological changes. Moreover, vasospasms caused by low-voltage alternating current may predispose individuals to ischemic stroke. Therefore, clinicians should consider the possibility of neurological complications, even if the onset of the symptoms is delayed, and should perform diagnostic tests, such as electrophysiology or imaging, when patients present with weakness following an electric injury.

High Voltage Electrical Injury and Prevention

PURPOSE: High voltage electrical injury mainly occurs in the industrial field. It can cause serious complications and sequelae that lead to high social and economic costs. We investigated the causes of this to try to help prevent these injuries. METHODS: We reviewed 128 patients who incurred high voltage electrical injury during a 3-years period from Jan. 1, 2006 to Dec. 31, 2008. We performed a retrospective analysis of the medical records to review the epidemiology. We also performed a survey by telephone. The survey questions addressed the following: the duration of work, wearing safety equipment, the reason for working without safety equipment, did they receive safety education, was the safety education adequate, recognition of a high tension wire before working and did they understand the effect of high voltage on the human body. RESULTS: The safety education was relatively carried out well. But most patients did not wear safety equipment even though they knew they had to wear it (92%). The major reason was discomfort of wear it (72%). The hand was the most common injury site (80%). Most injuries occurred with 22,900 volt or less (92%). In spite of safety education, many patients were unaware of the effects of electrical injury on their body. CONCLUSION: Strengthened safety education can play a significant role in preventing high voltage electrical injury. At this point, the doctors who are experienced in treating high voltage electrical injury must actively participate in this safety education. We suggest that handy safety equipment can lessen the incidence of high voltage electrical injury. It is essential to develop a handy safety glove for 22,900V with considering that the hand was the most common injury site and the most frequent voltage for injury was 22,900 volt or less.

A Follow up Study of Cognitive Dysfunction after High Voltage Electric Injury: a F-18 FDG-PET Study

We report a 43-year-old male who suffered cognitive dysfunction after an electric injury. He underwent evaluation for cognitive dysfunction and cerebral glucose hypometabolism at 1 week and 6 months. In contrast to the progressive decline of frontal lobe functions and visuospatial functions, memory and depressive mood were improved. SPM99 showed hypometabolic areas in the frontal and occipital lobes which were widened. Moreover new cingulate lesions appeared. This illustrates that the progression of derangement of cerebral glucose metabolism is correlated with neuropsychological impairment.

Evaluation of the Nervous and Vascular Systems in Erectile Dysfunction Patients after Electric Injuries / 대한비뇨기과학회지

PURPOSE: There is a high prevalence of erectile dysfunction (ED) after electric injuries, but our medical understanding of ED after electric injuries is scanty at best. Thus, the authors attempted to investigate nocturnal penile tumescence (NPT), bulbocavernosus reflex latency (BCRL) and penile duplex Doppler ultrasonography (PDDU) for the patients who suffer from ED after electric injuries. MATERIALS AND METHODS: Of the patients who visited our Burn Care Center between January 2005 and February 2006, ten male patients (aged 20 or older) who complaining of ED after electric injuries underwent NPT, BCRL and PDDU. RESULTS: The patients' mean age was 38.1 years (age range: 25-54), and the numbers of patients exposed to whole body, upper-lower extremity and upper-upper extremity pathways of the electrical current were 1, 2 and 7, respectively. For the patient exposed to the whole body pathway, abnormal findings were observed on all the tests. For one patient who experienced two upper-lower extremity pathways, normal findings were seen on all the tests, while the other patient showed an abnormal NPT, an normal BCRL and an arteriogenic ED. Three of the patients who experienced the upper-upper extremity pathway showed normal findings on all the tests. The other two in the group showed an abnormal NPT, a normal BCRL and arteriogenic ED; the other one showed a normal vascular function, a abnormal NPT and no reaction to BCRL; the other one showed an abnormal NPT, a delayed BCRL and an arteriogenic ED. CONCLUSIONS: More abnormal findings were seen in NPT, BCRL and PDDU for the cases associated with upper-lower body or whole body electrical current pathways, as compared to patients whose electrical pathways were limited to the upper body.

Electrical Injury-Induced High-Degree Atrioventricular Block Requiring a Permanent Pacemaker

Electrical injury may lead to a conduction disorder of the heart. We report here on a 36-year-old man, who was treated with a permanent pacemaker, after an electrical injury induced high-degree atrioventricular block and clinical manifestations (dizziness and dyspnea).

Electrical Injury As A Possible Cause of Sick Sinus Syndrome

Electrical injury is a serious public health problem. Heart is one of the most frequently affected organs. Electrical injury can cause life-threatening cardiac complications such as asystole, ventricular fibrillation, and myocardial rupture. In this case report, we present a 20-yr-old male patient with sick sinus syndrome that developed years after electrical injury.