Sudden death caused by tension pneumothorax after rupture of a thoracic aortic aneurysm. Case report

A rare case of fatal tension pneumothorax is reported. An aged Japanese man with marked subcutaneous emphysema of the neck was found collapsed in a betting office. He was ascertained to have left tension pneumothorax, based on radiographic examinations carried out before his death. At autopsy, severe pneumomediastinum was observed, and the descending thoracic aorta with a ruptured dissecting aneurysm was closely adhered to the left lung pleura. The hemorrhage spread into the pulmonary parenchyma and finally spouted out from the surface of the lung apex. Because the blood loss itself was not fatal in quantity, it is concluded that the patient died of tension pneumothorax caused by a lung penetration from the rupture of an aortic aneurysm.     

Fatal paradoxical air embolism diagnosed by postmortem imaging and autopsy

The recognition and visualization of an arterial gas embolism are difficult. We report a case of sudden death caused by paradoxical air embolism of coronary and cerebral arteries, diagnosed by the pre autopsy computed tomography (CT) scanning. A 54-year-old woman suddenly died after the self-removal of the jugular vein catheter. Postmortem imaging examination using CT scanning showed multiple gas embolisms in the cerebral arteries, pulmonary artery, right atrium and ventricle, left ventricle, aorta, and coronary arteries. These findings suggested that the occurrence of acute ischemia of the brain and heart caused by massive air inflow to the artery. Conventional autopsy revealed a patent foramen ovale of the heart. These results indicated that the patient died of paradoxical air embolization of the coronary and cerebral arteries through a patent foramen ovale because of right-to-left shunting. The use of postmortem imaging as an aid for conventional autopsy has proved to be of advantage in the case of gas embolism.     

Severe Cardiac Rupture by Only One Blow to the Chest in a Young Boy: An Autopsy Case

Cardiac rupture by blunt chest trauma is commonly seen after motor vehicle accidents and falls; however, it is rarely caused by a blow to the chest. We herein report an autopsy case of a high school boy who sustained severe right ventricular rupture by only one knee kick to the chest during a quarrel. He was hospitalized and developed cardiopulmonary arrest. Emergency surgery was performed, but the patient died. The autopsy revealed no external severe trauma or deformation, but the side wall of the right ventricle contained a large V‐shaped laceration. The other thoracic organs had no injuries. This case illustrates that severe cardiac rupture can occur by only one blow to the chest. Blunt cardiac injuries can occur even if no severe injuries are present on the body surface. We should consider the possibility of severe cardiac injuries regardless of the presence of external injuries.     

Occlusion of left and right coronary arteries and coronary sinus following blunt chest trauma

Blunt chest trauma from rapid automobile airbag deployment causing coronary artery occlusion and myocardial infarction is a rare but potentially fatal condition. We present the case of a 37-year-old man who developed extensive anterior and inferior myocardial infarction because of occlusion of both left anterior and right coronary arteries following blunt injury to the chest in a car accident. The patient was scheduled for emergency coronary angiography but left and right coronary ostia were not cannulated because of thrombus formation probably. The patient died, and the autopsy revealed external compression by epicardial hematomas involving separately left and right coronary arteries and the coronary sinus without signs of coronary and/or aortic dissection. To our knowledge, this is the first case presenting occlusion of both coronary arteries secondary to blunt chest trauma causing acute myocardial infarction in a young man without signs of prior coronary artery disease.     

Cardiac rupture due to severe fatty infiltration in the right ventricular wall

An extremely rare case of sudden death caused by cardiac rupture due to severe fatty infiltration in the right ventricular myocardium is presented. The patient, a 74-year-old woman, had no history of chest trauma, hypertension, or pulmonary disease. The autopsy showed a small tear in the right ventricle and cardiac tamponade, but no coronary artery lesion. In the right ventricular myocardium, muscle fibers were definitely atrophic or absent, with massive fatty replacement. Fatty infiltration of the myocardium, if severe, can be a cause of serious cardiac dysfunction or, occasionally, sudden death.     

Venous air embolism in homicidal blunt impact head trauma. Case reports

From 1992 through 1997, there were 41 deaths by homicidal blunt impact head trauma in Hillsborough County, Florida. Twenty-one cases were excluded from the study because of putrefaction or survival beyond the emergency department doors, leaving 20 cases for the study. One of the 15 nonputrefied victims found dead at the scene and 1 of the 5 victims pronounced dead in the emergency department had definite venous air embolism. Victim 1 was found dead, bludgeoned with a concrete block, and had open vault and comminuted basilar skull fractures. The dura forming the right sigmoid sinus at the jugular foramen was lacerated. A preautopsy chest radiograph and examination under water documented gas in the pulmonary artery and right ventricle. Victim 2 was bludgeoned with a steel stake and was pronounced dead on arrival in the emergency department. He had open comminuted vault fractures, a transverse basilar skull fracture, and lacerations of the brain. Direct examination and preautopsy chest radiography revealed air in the right side of the heart. A third victim, with basilar fractures, had a small gas bubble in the pulmonary artery not detected by the case pathologist. A fourth victim, with a basilar skull fracture, had an unusual radiographic finding that was thought to be air in the posteromedial aspect of the lower lobe of the left lung but could not be excluded as an air embolus. Optimal postmortem documentation of venous air embolism includes the demonstration of the embolus and the site of air ingress. This study demonstrates that venous air embolism occurs in some victims of homicidal bludgeoning and suggests that when significant, it is easily demonstrated in the absence of putrefactive gas formation. The presence of venous air embolism can serve as evidence that a victim was alive and breathing at the time of the infliction of head wounds. In the belief that venous air embolism might be underdiagnosed in many medical examiner offices, the authors have sought to bring attention to the entity by publishing their experience with it in cases of bludgeoning.     

Air embolism or putrefaction? Gas analysis findings and their interpretation

Gas was detected in the hearts of 111 necropsy cases. The gas was quantified and then analyzed by gas chromatography. In 70 cases H2, a clear marker of putrefaction, could be identified in the samples. After critical consideration, air embolism was accepted in 36 of the remaining cases. In nearly all instances, severe skull trauma or stab wounds to the neck or clavicular region gave rise to the air embolism. When the gas analysis data were compared, clear-cut differences were found between the two groups of putrefaction and air embolism. CO2 concentrations below 15%, N2 concentrations above 70%, and a CO2/N2 ratio below 0.2 proved to be good criteria to determine an air embolism. However, gas volumes, O2 concentrations, and CO2/O2 ratios largely overlapped in the two groups. Air embolism samples consistently had lower O2 concentrations and higher CO2 concentrations than atmospheric air, and this was evidently independent from incipient putrefaction. We suggest that these deviations result from a gas exchange between the venous blood and the embolized air volume taking place in the right heart ventricle. The dimensions of the concentration shifts may be understood from severe agonal hypoxia and hypercapnia.     

Spinal epidural haematoma after blunt trauma to the neck and hyperflection of the cervical spine

Spinal epidural haematomas (sEDH) can be regarded as rare events, in principle a spontaneous and a traumatic aetiology can be distinguished. Spontaneous spinal epidural haematomas can arise, e.g. from vascular malformations, coagulopathies, etc. On the other hand, traumatic sEDH are related to, e.g. spinal trauma or intraoperative vascular injuries. With regard to clinical significance, spinal epidural haematomas accompanied by transient mild neurological symptoms up to lethal outcomes have been observed. We report on a 53-year-old male alcoholic who was found in the kitchen of his asylum in a grotesquely fixed body position, with his head and cervical spine in a maximum anteflected position. A general practitioner had ruled for a non-natural manner of death due to "broken neck" and alcohol intoxication, therefore, the prosecution authorities called for a medicolegal autopsy. At autopsy, paravertebral soft tissue haemorrhage in between the shoulder blades was disclosed. Furthermore, a spinal epidural haematoma, extending from the foramen magnum down to the middle portion of the thoracic spine was found. No fractures of vertebrae nor lesions of spine ligaments or bleedings of intervertebral discs were found. Blood alcohol concentration was determined 1.92 g/l and urine alcohol concentration was 1.76 g/l. Further morphological findings were cerebral oedema and cardiac hypertrophy; the urinary bladder was found filled to bursting. Neuropathological investigations confirmed the presence of the spinal epidural haematoma and assigned lethal significance to this finding. There were no histological signs of axonal injury. Reconstruction revealed that when sitting on a chair in a drunk condition, the individual's upper part of the body had fallen backwards in the corner and subsequently got stuck with maximum anteflection of the head and cervical spine, causing rupture of vessels and spinal epidural haematoma. Acute respiratory failure caused by impairment of the phrenic nerve following spinal epidural haematoma with potential synergism of alcohol intoxication was ascertained as the cause of death.     

颅脑损伤部位与智力评估分析

目的探讨颅脑损伤部位与智力损伤的关系。方法315例颅脑外伤者根据疾病诊断分成8组：蛛网膜下腔出血组、脑震荡组、硬膜外血肿组、硬膜下血肿组、颞叶损伤组、额叶损伤组、顶叶损伤组、枕叶损伤组、广泛性损伤组和其他组，按中国修订韦氏成人智力量表进行测试，分析性别、年龄、文化程度、损伤部位与智商水平的关系。结果颅脑外伤后的平均总智商（FIQ）为64．45±16．09。性别对颅脑外伤后的智商水平影响不明显（P=0．578）；老年颅脑外伤后的智商水平较青年和中年高（P〈0．01）；文盲者颅脑外伤后的智商水平较文化程度高者低（P〈0．01）。各组智商水平高低为：其他组〉蛛网膜下腔出血组、脑震荡组〉硬膜外血肿组、硬膜下血肿组〉颞叶损伤组、额叶损伤组、顶叶损伤组、枕叶损伤纽〉广泛性损伤组。同时左额叶损伤组的智商水平较右额叶损伤组低；右颞叶损伤组的操作智商（PIQ）明显比左颞叶损伤组低，而言语智商（VIQ）则反之（P〈0．01）。结论颅脑外伤后的智力损伤与损伤部位密切相关。     

Sudden death in a child due to an intrathoracic paraganglioma

A 12-year-old boy under treatment for asthma was found dead in his home. The autopsy revealed a large posterior mediastinal mass that completely compressed the upper lobe of the right lung and the associated airways. This mass extended from the right costovertebral sulcus into the thoracic spinal canal through the spinal foramen and compressed the spinal cord. It was located in the epidural space and was adherent to a nerve root. The histologic and immunocytochemical features were that of a paraganglioma. Although neurogenic tumors are the most common posterior mediastinal masses in the pediatric population, paragangliomas are rare, and spinal involvement has not been described in children. In addition, sudden death has not been reported in association with any of the 13 cases of posterior mediastinal paraganglioma described in the literature as involving the spine. This case illustrates an unusual cause of sudden death in a pediatric patient due to a benign neoplasm.     

A case of aortic dissection caused by blunt chest trauma

A 74-year-old woman was struck by a car travelling at about 50 km/h. On arrival at hospital, a CT scan showed dissection of the ascending and descending aorta. She collapsed and died suddenly 8h later. At autopsy, there was massive bleeding into the left pleural cavity, ruptures of the pericardium and right ventricle, and a type A thoracic aortic dissection. The cause of death was haemorrhagic shock due to rupture of the pericardium and delayed rupture of the right ventricle following trauma to the chest. The thoracic aortic dissection was not the direct cause of death although histological examination did reveal that it occurred in the accident. Traumatic aortic dissection is rare although traumatic aortic rupture is a major cause of death after blunt chest trauma. This paper discusses the mechanisms, and factors involved in aortic dissection caused by blunt trauma.     

Embolism of heart tissue to the middle cerebral artery as a complication of heart surgery.

After suture closure of an intraarterial septal defect an atrioventricular block occurred in a 6 years old child. Therefore, the suture was removed and the defect closed by a Dacron patch. The sinus rhythm returned. After the operation convulsions occurred, the patient died after 16h which was considered to be due to cerebral air embolism. Autopsy confirmed a correct operation, but the right middle cerebral artery has been found to be completely occluded by heart muscle and pericardial fat tissue.     

An autopsy case of intraoperative death due to pulmonary fat embolism—possibly caused by release of tourniquet after multiple muscle-release and tenotomy of the bilateral lower limbs

We report a case of a juvenile male with muscle rigidity caused by cerebral palsy who experienced intraoperative sudden death due to pulmonary fat embolism after multiple muscle-release and tenotomy of the bilateral lower limbs. Data were obtained through review of the surgical and anesthesia records, as well as from autopsy and histopathological examination. All surgical procedures were performed within the same operation, beginning with the right lower limb and then proceeding with the left lower limb, with application of a pneumatic tourniquet to avoid intraoperative hemorrhage. Slight changes in the hemodynamics were noticed after release of the right tourniquet. Further, sudden onset of hypotension, severe bradycardia, and a marked decrease in percutaneously monitored oxygen saturation occurred just after release of the left tourniquet when the left limb was raised for casting. The patient died despite immediate and vigorous cardiopulmonary resuscitation. At autopsy performed 20 h after death, examination of the lungs revealed a pale surface, slight edema, and obvious fat droplets in the vessels at the cut surfaces. Histopathological examination with fat staining was notable for the presence of pulmonary fat embolism. These results suggest that restoration of venous return after removal of the tourniquet combined with massive fat embolism from dead spaces was the likely cause of death.     

Fatal Venous Air Embolism Following Intravenous Infusion*

Abstract: Venous air embolism has been reported as a complication of invasive diagnostic and therapeutic procedures or accidental trauma. Little is known about the incidence of air embolism after minimal intravenous manipulations such as the insertion of a peripheral intravenous cannula. Only when large amounts of air sufficient enough to block the cardiovascular system enter, the patient develops symptoms and signs of severe neurological injury, cardiovascular collapse, or death. The dead body of a 14‐year‐old boy was brought for postmortem examination with allegations of death from negligence during treatment. He was treated for pain in the abdomen in a hospital by attendants in telephonic consultation with a medical practitioner. Following intravenous infusions, the boy died suddenly in respiratory distress. Gross findings indicated the death to be from venous air embolism. Chemical analysis, histopathology, and microbiology ruled out other causes of death. Dilemmas of the case with difficulties in diagnosis are being presented herewith.     

Barotrauma and air embolism in hyperbaric oxygen therapy

A 69-year-old woman underwent hyperbaric oxygen therapy because of a nonhealing ulcer of her foot. During decompression, she developed a left-sided hemiplegia and confusion. Recompression resulted in transient neurologic improvement, but she eventually became comatose. Ventricular dysrhythmias developed and she died without regaining consciousness 17 h after onset of symptoms. An autopsy revealed diffuse interstitial pulmonary fibrosis with severe paracicatricial emphysema, chronic interstitial inflammation, and chronic bronchitis with abundant intrabronchial mucus. There was extensive multifocal ischemic injury of the cerebral cortex. The hippocampi, basal ganglia, and cerebellum were spared. Scattered acute myofiber necrosis was present in the heart. Clinical presentation and autopsy findings strongly support the diagnosis of air embolism and illustrate a potential risk of hyperbaric oxygen therapy in patients with preexisting pulmonary disease.     

Visualization and quantification of air embolism structure by processing postmortem MSCT data

Venous air embolism (VAE) is an often occurring forensic finding in cases of injury to the head and neck. Whenever found, it has to be appraised in its relation to the cause of death. While visualization and quantification is difficult at traditional autopsy, Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) offer a new potential in the diagnosis of VAE. This paper reports the findings of VAE in four cases of massive head injury examined postmortem by Multislice Computed Tomography (MSCT) prior to autopsy. MSCT data of the thorax were processed using 3D air structure reconstruction software to visualize air embolism within the vascular system. Quantification of VAE was done by multiplying air containing areas on axial 2D images by their reconstruction intervals and then by summarizing the air volumes. Excellent 3D visualization of the air within the vascular system was obtained in all cases, and the intravascular gas volume was quantified.     

大鼠实验性脑梗死早期CT值和GFAP表达变化的研究

目的探讨大鼠24h内实验性脑梗死CT值及脑内胶质纤维酸性蛋白(GFAP)的表达变化,以间接推测脑梗死的发生时间。方法参照Longa线栓法建立大鼠大脑中动脉栓塞脑梗死模型,在不同时相点进行头颅CT扫描,测量右侧脑梗死和左侧未梗死区脑组织的CT值并求出两侧的差值。同时用免疫组化检测脑内GFAP的表达变化。结果6h组大鼠CT平扫均有明确的脑梗死灶,梗死与非梗死两侧脑组织CT值的差值与梗死时间呈直线正相关,GFAP表达与梗死时间也有一定的相关性。结论血管栓塞引起的脑梗死最早于梗死发生后6h可以诊断,并可通过脑梗死与非梗死两侧CT值的差值计算及GFAP表达变化来推测脑梗死发生的时间。     

Biomechanical features of spinal trauma depending on conditions of the trauma

The aim of the study was to investigate biomechanical features of spinal trauma (fractures) depending on external impact, position of a human body or its parts in the moment of the trauma and before it; to reveal morphological signs of fractures characterizing specific trauma mechanisms. From a position of theoretical mechanics, the vertebral column is an elastic stem the strength of which depends on elastic properties of the pulpous nuclei and intervertebral disks, the column length and curvature. To determine the mechanism of the trauma, it is recommended to make the following measurements: the length of the body, the length of the vertebral column, the length of the cervical, thoracic, lumbar parts, size of the chest kyphosis.     

Fatal bilateral pneumothoraces after electroacupuncture treatment: A case report and literature review

Acupuncture is practiced as a complementary medicine worldwide. Although it is considered a safe practice, pneumothorax is one of its most common serious complications. However, there have been few reports of deaths due to pneumothorax after acupuncture treatment, especially focused on electroacupuncture. We report an autopsy case of a man in his 60s who went into cardiopulmonary arrest and died immediately after receiving electroacupuncture. Postmortem computed tomography (PMCT) showed bilateral pneumothoraces, as well as the presence of numerous gold threads embedded subcutaneously. An autopsy revealed two ecchymoses in the right thoracic cavity and a pinhole injury on the lower lobe of the right lung, suggesting that the needles had penetrated the lung. There were marked emphysematous changes in the lung, suggesting that rupture of bullae might also have contributed to bilateral pneumothoraces and fatal outcome. The acupuncture needles may have been drawn deeper into the body than at the time of insertion due to electrical pulses and muscle contraction, indicating the need for careful determination of treatment indications and technical safety measures, such as fail-safe mechanisms. This is the first case report of fatal bilateral pneumothoraces after electroacupuncture reported in the English literature. This case sheds light on the safety of electroacupuncture and the need for special care when administering it to patients with pulmonary disease who may be at a higher risk of pneumothorax. This is also the first report of three-dimensional reconstructed PMCT images showing the whole-body distribution of embedded gold acupuncture threads, which is unusual.     

Retrograde venous cerebral air embolism from disconnected central venous catheter: an experimental model

There are few reported cases of death attributed to retrograde cerebral air embolism from central venous catheter. The pathophysiological mechanism and the necessary conditions are not fully understood, also because of missing experimental data. We performed experimental simulation while working on a possible case of retrograde cerebral air embolism. A hermetic system consisting of two containers connected to each other and to an electric pump by means of rubber hoses was built. In this system, a fluid (water and blood) could continuously flow under conditions similar to those of the common jugular vein. The part of the system representing the jugular vein could be freely positioned at angles between 0 and 90°. A central venous catheter was inserted into this part. After disconnection, the behavior of the air bubbles entering the hose through the tip of the catheter was evaluated at different positions. At angles between 0 and 45°, the air bubbles followed the fluid flow. At angles >45°, the air bubbles showed the tendency to flow upstream; this phenomenon was more evident the more vertically the hose was located. We were able to demonstrate that a retrograde air embolism can be caused by a disconnected catheter and is even more likely if the neck is in a vertical position.