Structural principles of hemostatic processes

The formation of the hemostatic plug on areas of skin injury is characterized as a sequence of structure-forming processes ending in the formation of an impenetrable barrier. The morphology of this barrier is further elucidated by means of scanning- and transmission electron microscopy. Especially the fibrin coating of the injury shows a completely different formation than is deducible from the solely hemostaseologically orientated view of the formation of the hemostatic plug. These structure-forming processes are: activation of the intrinsic clotting system by means of explosion-like destruction of thrombocytes with an immediate formation of a fibrin clot within seconds after the injury. Later during the process the fibrin clot is then condensed and as a function of thrombocyte dependent retraction receives its final fibrin stabilisation and modellation towards an occluding plug. The very narrow net formation of fibrin fibers is interpreted as dependent on the destruction of thrombocyte pseudopodia using their round shape as a rail for fibrin fiber formation. Disturbances of clot formation of postmortal clots compared to vital clots are interpreted as functional thrombocytic distortions, especially of the thrombocytic energy metabolism. Extracorporal clotting of blood drops after extreme ischemia resemble fibrin structures and fibrin structure formation distortions of postmortal origin.     

Characteristics of fibrin formation in stab wounds of the skin, determined by scanning electron microscopy

In an investigation on fibrin formation in skin cut wounds on guinea pigs using scanning electron microscopy, it was established that immediately after the infliction of cuts on live animals, a fine, netlike fiber structure of fibrin forms that gradually covers the entire wounded surface. In the period early after the cuts blood-forming elements attach to the fibrin net through numerous fine fibrin fibers, which incorporate a great number of thrombocytes. Postmortem investigations of these wounds showed that the fibrin net formed preserves its structure. It was also established that a fibrin net forms over skin wounds that were inflicted at different periods after death. In the wounds in the early periods after death, the fibrin net formed was very similar to the one established on wounds inflicted on living animals. Our investigation describes some peculiar characteristics of the fibrin net formed in living animals; there is a fine fiberlike net and the quantity is definitely larger. These characteristics permit the establishment of whether the wounds occurred before death and how much time has lapsed since then.     

Zur ultrastruktur vitaler,postmortaler und autolysierter gerinnsel

Investigations on animal experimental and human tissue material (skin, musculature, liver) with the scanning electron microscope are reported. These studies were carried out to clarify open questions on extravascular fibrin structures after blunt and sharp traumatization of vital and postmortem nature. The network formation which was already characterized earlier as typically vital and the irregular structure of postmortem coagula could be demonstrated even with modification of the traumatization, especially in tissue hematomas. Experimental investigations on autolysis revealed an exceedingly good preservation of the structure of vital coagulum material with massive damage and granular decomposition of fibrin fiber structures produced postmortem. The structural differences in the mode of interlinking of the fibrin was shown up especially clearly by the autolysis, which suggests an application as preparation technique for the question specified.Special modifications of the preparation technique (fixation according to Karnovsky, critical-point drying) did not provide such substantial advantages for routine investigations that they might be generally recommended.Sources of artefacts and possibilities of misinterpretation of findings as well as more advanced techniques are discussed.     

对纤维蛋白诊断生前伤的评价——45例枪弹创组织的MSB染色和扫描电镜对比观察

生活反应是诊断生前伤的主要根据.近二十年来,法医病理学在研究生前伤和死后伤的诊断中,采用了多种新兴技术,如扫描电镜技术、酶组织化学技术、酶标技术、电泳技术等,促使生前伤的诊断水平有明显提高.伤后存活1小时死亡者,大部分皆可获得明确诊断;立即死亡或在濒死期形成的损伤,由于生活反应甚微,或受腐败等     

死后肌肉切创创壁纤维蛋白的扫描电镜观察

用扫描电镜观察大鼠肌肉组织切创创壁纤维蛋白网的形成和形态,发现生前和死后8小时内的切创壁,均有纤维蛋白网形成,两者形态无显著差异。死后16小时,切创创壁无纤维蛋白网形成。     

扫描电子显微镜下生前和死后枪弹创的对比观察

本文用扫描电镜,对11例生前枪弹创和12例死后不同时间形成的枪弹创作对比观察。结果发现,生前枪弹创有大量红细胞和血小板凝块,纤维蛋白网形成,死后10min内的枪弹创亦有少许散在红细胞和纤维蛋白形成,很少见纤维蛋白网。死后25min的标本仍可见稀疏的红细胞,但无纤维蛋白形成。作者认为在扫描电镜下诊断生前枪弹创,需全面观察,综合分析。     

Cerebral ischemia or post traumatic thrombosis of the A. carotis occuring to a car driver (author's transl)]

A short while after leaving a public-house a 71 year old man as the driver of his car was involved in a head-on collision with another car. On admission to a hospital he was unconscious with a distinct debility for the left side of his body and showed a changing anisocoria. Angiography of the right carotid artery revealed an occlusion. It was suspected that this was the terminal state of a generalized arteriosclerotic occlusion which was considered being the reason for the accident. The autopsy-findings showed, however, a posttraumatic thrombosis (whiplash-trauma of the cervical vertebral column) of the right arteria carotis and of the right arteria vertebralis with thromboembolia in a small pontine artery with an infarct-like ischemic softening. The differentiation from an apoplexia is of importance for the differential diagnosis.     

Postmortem diffusion of drugs from the bladder into femoral venous blood.

We describe significantly elevated drug concentrations in the femoral venous blood due probably to postmortem diffusion from the bladder. A 16-year-old deceased male was found in a shallow ditch in winter. The estimated postmortem interval was 9 days and putrefaction was not advanced. The cardiac chambers contained fluid and coagulated blood and a small amount of buffy coat clots. Diffused hemorrhages were found in the gastric mucosa. The bladder contained approximately 600 ml of clear urine. Gas chromatographic-mass spectrometric analysis of the urine disclosed allylisopropylacetylurea (a fatty acid ureide sedative), diphenhydramine, chlorpheniramine and dihydrocodeine. The cause of death was considered to be drowning due to a drug overdose and cold exposure. The concentrations of diphenhydramine, free dihydrocodeine and total dihydrocodeine in the femoral venous blood (1.89, 3.27 and 3.30 microg/ml, respectively) were much higher than those in blood from the right cardiac chambers (0.294, 0.237 and 0.240 microg/ml, respectively). Urine concentrations of diphenhydramine, free dihydrocodeine and total dihydrocodeine were 22.6, 37.3 and 43.1 microg/ml, respectively. The stomach contained negligible amounts of diphenhydramine, free dihydrocodeine and total dihydrocodeine (0.029, 0.018 and 0.024 mg, respectively); concentrations of these drugs in the femoral muscle were 0.270, 0.246 and 0.314 microg/g, respectively. These results indicate that postmortem diffusion of diphenhydramine and dihydrocodeine from the bladder resulted in the elevated concentrations of these drugs in the femoral venous blood. Not only high urinary drug concentrations but also a large volume of urine in the bladder might accelerate the postmortem diffusion.     

The effects of drying the rinsed dissected heart on postmortem heart weight

Blood and blood clots should be removed from the heart chambers before being weighed. The actual method in removing blood and blood clots may vary and can include manual removal with subsequent rinsing the heart in water. It is unclear whether drying the rinsed heart affects the heart weight. The objective of this article was to investigate the effects drying the rinsed dissected heart (residual rinsing water) on postmortem heart weight. The prospective study compared 44 dissected heart weights after being rinsed and after being pat dried. An average 18–20 g of residual rinsing water (4% of heart weight) was present in the dissected heart. The amount of residual rinsing water correlates positively with heart weight. The effects of drying the rinsed dissected heart were considered clinically insignificant. Although being clinically insignificant, this study highlights the lack of standardized approach in weighing the heart and the potential implications in interpreting heart weights.     

Lethal Laryngopyocele

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

Ultraviolet 365 as an Alternative Light Source for Detection of Blood Serum

The use of alternative light sources (ALS) in bloodstain analysis has focused on dried (whole) blood, while information on detection of blood serum is lacking. Serum detection by ALS could provide valuable information at a crime scene, as serum may become separated from blood during clotting and cast off, especially in cases where the victim is moved. Additionally, a perpetrator may concentrate on the removal/scouring of dried blood with small amounts of serum going unnoticed, as it dries relatively clear on certain objects. In this report, the detection of human blood serum was evaluated using ultraviolet (UV) light at two different wavelengths. These results show that ultraviolet (UV) at 365 nm (UV365) was effective in the detection of even small amounts of blood plasma and serum, compared with UV at 395 nm, which was not. UV365 was also found to be useful in distinguishing blood imprints from clotting blood which had been transferred to material versus blood that had been added directly. Taken together, these results demonstrate that UV365 may be utilized as a simple, nondestructive method for blood serum detection.     

枪弹创纤维蛋白形成能力的免疫组化研究

采用免疫组化PAP染色法，对57例人体枪弹创标本的纤维蛋白形成能力进行检测。结果发现，所有生前枪弹创均有纤维蛋白形成祖创缘邻近皮肤组织内毛细血管内皮细胞以及血管内充盈的红细胞膜上亦呈棕色阳性染色；死后30min内形成的枪弹创均有纤维蛋白形成；死后37min后形成的枪弹创无纤维蛋白形成，说明死后30min，纤维蛋白形成能力仍存在。作者认为，仅根据损伤局部有纤维蛋白形成即判断为生前伤是不恰当的，尚应结合损伤部位、损伤程度、损伤类型以及其它生活反应综合评定，不宜单凭纤维蛋白判断。     

颅骨骨折断面细微结构的观察研究

作者利用扫描电子显微镜,对颅骨骨折断面上微细结构的形态学特征进行了观察与研究,发现在颅骨骨折断面上有微细的骨折裂线,向断面深部的骨质中延伸,其宽度为5至100um不等,主要分布在颅骨外板内,或外板与板障的交界处.分布于板障内的微细裂线可造成骨小梁横行、纵行和螺旋形骨折.骨折时,骨基质中的胶原纤维束可被分离或断裂,各胶原纤维层可分开.骨内血管可被骨折裂线横断或纵形撕裂,损伤的血管可被从哈佛氏管中拉出.生前骨折时,在微细裂线的深方可清楚见到纤维蛋白网和红细胞相互粘集,死后骨折则未见到此现象.本文还探讨了颅骨骨折发生的机理和推断生前骨折的可能性.     

Tissue distribution of intubation-related lidocaine in brain-dead patients

Tissue distribution of lidocaine that was used for endotracheal intubation during cardiopulmonary resuscitation (CPR) was measured in 3 patients who were brain-dead or near brain death. Case 1 was a 69-year-old female whose heartbeat was restored by CPR but stopped 10 hours later. The lidocaine ratios of cerebrum to blood (2.04) and diencephalon to blood (1.01) were within ranges of those found in non-brain-dead patients. Case 2 was a 77-year-old female whose heart resumed beating after CPR but stopped 66 hours later. The lidocaine ratios of cerebrum to blood (5.69), diencephalon to blood (18.7), and cerebellum to blood (11.3) were much higher than those in non-brain-dead patients. Case 3 was a 48-year-old male who had cardiopulmonary arrest following an acute subarachnoid hemorrhage. His heart resumed beating after resuscitation but ceased beating 114 hours after admission. Lidocaine was detected only from the cerebrum, cerebellum, and blood clots in the superior sagittal sinus at levels of 0.028, 0.024, and 0.007 mug/g, respectively. Tissue distribution of intubation-related lidocaine in brain-dead patients is useful as supplementary data for reviewing hemodynamic changes in their brains during medical treatment.     

Diagnosis of carbon monoxide poisoning following embalming and exhumation

Clots of blood, which were found in the cardiac ventricles at an autopsy of an embalmed corpse, were to analyse for carbon monoxide. It was not possible to determine reliably the CO-Hb-content of the blood clots with the known methods. Therefore a new procedure was developed. Carbon monoxide was released by a solution of nitric acid and determined gas chromatographically by a headspace method. In the same vessel the iron-content of the sample was measured after decomposition with atomic absorption spectrometry. This procedure is especially suitable for samples like putrid or heat-clotted blood.     

Sudden unexpected death in a child with varicella caused by necrotizing fasciitis and streptococcal toxic shock syndrome

A 4-year-old child with chickenpox infection for 5 days prior to death complained of swelling and pain in his right leg that required medical assistance in the emergency department. Radiologic study was normal, and analgesic and bandage of the leg were prescribed. Some hours later, he presented cyanosis, dizziness, and vomiting and collapsed. A complete forensic autopsy was performed 12 hours after death. External examination of the body showed numerous crusty varicella skin lesions, especially over the trunk, and swelling and reddening of his right leg. The brain was swollen, with cerebellar herniation, and both adrenal glands were hemorrhagic.Microscopically, neutrophilic infiltration and muscle fiber necrosis were observed in soft tissues of his right leg, and fibrin microthrombus were numerous in capillaries of the plexus choroideus, larynx, lungs, and adrenals. Bacterial emboli were present in most of the tissues. Microbiologic cultures of blood and cerebrospinal fluid showed group A beta-hemolytic streptococcus (Streptococcus pyogenes). Death was attributed to fulminant streptococcal toxic shock syndrome, with necrotizing fasciitis as a complication of varicella.     

损伤经过时间的实验研究

作者在全身麻醉及无菌条件下,通过在大白鼠背部皮肤造成的切创创口,于伤后不同时间杀死.每组中1只于处死前8小时注射秋水仙碱以观察核分裂.取损伤处皮肤,经福尔马林固定、石蜡切片、HE染色、Gorden和Sweet染色(网状纤维)、Weigert染色(弹力纤维)、PTAH染色(纤维蛋白)和Van Gieson染色,于显微镜下观察.结果发现创口逐日缩小,但其中24小时创口较12小时创口有所扩大,伤后第6～7日创口呈突击式缩小.通过组织学变化观察,作者对创口收缩现象在判断损伤时间的意义及形成机理作了讨论.     

Injuries of the large arteries of the brain and vital reactions. An electron microscopy study

In 90 forensic autopsies (Craniocerebral injury, gunshot, stabbing, blow, strangulation, etc.), semithin sections of great arteries were prepared from around 770 Epon blocks and checked for vital reactions at the mural and intimal ruptures. In 21 cases in which death had occurred immediately or soon after the trauma, with three exceptions, there was a subsequent electron microscopic investigation. In all six mural ruptures and in five of ten intimal ruptures, thrombocyte aggregates were found at the rupture margins. In five intimal ruptures, the possibility of the occurrence of preparations injuries had to be considered. In five cases, the results of the histological study were negative. The success rate is limited in principle in such a screening test since there are technical difficulties in preparing serial sections on long vessels. Death was rapid and the thrombocytes were observed to adhere to the injured wall sites immediately after the trauma. The "thrombocyte sign" is thus of substantial importance as the earliest local vital reaction. In two control cases (strangulation), thrombocyte aggregates were found at intimal ruptures of the basilar artery, which were regarded as the results of stretching via the vertebral arteries during attacks to the neck. The healing processes of intimal ruptures and traumatic medial necrosis in incomplete ruptures occurring later in life are discussed. Even if a cadaver is a few days old, the histological findings at the level of the thrombocytes can be evaluated.     

Identification of mechanical asphyxiation in cases of attempted masking of the homicide

Five homicides are described that had remained unexplained as to the causes of death after gross pathology. Although general signs of asphyxiation were present, they were lacking injuries specific of strangulation or oro-nasal occlusion. The diagnoses of asphyxiation were established by microscopical investigation of the lung and confirmed by subsequent police inquiries. An oro-nasal occlusion was involved in three cases, a strangulation or an oro-nasal occlusion, in another case. The victims were young and healthy. Toxicological investigations remained negative in four cases; one victim was anaesthetized by bromazepam and ether and had a blood alcohol concentration of 80 mg/100 ml. Lung histology and electron microscopy revealed acute emphysema, the development of a haemorrhagic-dysoric syndrome and a microembolism syndrome. With regard to the haemorrhagic-dysoric syndrome, the development of alveolar-interstitial edema is particularly important. This finding may also be diagnosed by light microscopy in semi-thin sections. It is emphasized that the combined action of several pathomechanisms is responsible for the rapid manifestation of the pulmonary lesions. Especially, the haemorrhagic-dysoric syndrome is brought about by the combined action of inspiratory intrapulmonary vacuum and raised intracapillary pressure. The complex pattern allows to compile the diagnosis of mechanical asphyxia even if there is no corresponding injury.     

A burning issue. The Japanese "fire basin"

This article presents two deaths due to acute carbon monoxide poisoning that occurred when charcoal-burning hibachis were used as heating sources in enclosed camping facilities. In both deaths, the levels of blood carbon monoxide saturation were at or slightly below the expected lethal level. Coronary arteriosclerosis may have contributed to one death, while oxygen depletion may have been a contributing factor in the other. These cases illustrate the danger of using such heating sources in enclosed spaces, due to their carbon monoxide-generating capability. We suggest that suitable warnings be placed on the hibachis themselves.