羊水栓塞诊断的方法学研究进展及法医学意义

羊水栓塞(amniotic fluid embolism,AFE)是指分娩过程中羊水进入母血循环,引起肺栓塞、休克甚至死亡等一系列严重症状的综合征。目前对于AFE的诊断为排除性诊断,方法缺乏灵敏性和特异性。因此随着以AFE为死因的孕产妇病死率的升高,寻找更精确的AFE诊断方法成为了法医学研究的重点。本文结合相关文献概述了AFE诊断方法的研究进展,希望能为法医学鉴定提供方法学参考。     

实验性兔羊水栓塞血浆凝血指标的含量变化

目的观察兔羊水栓塞(AFE)后血浆凝血指标的动态变化。方法采用怀孕家兔制作羊水栓塞动物模型,将不同性质的自身羊水注入兔血循环,分别在羊水注入前、注入后,5min、45min从兔心脏取血,用血凝仪检测血浆中各项凝血指标包括纤维蛋白原定量(FIB)、血浆凝血酶原时间(PT)、凝血酶凝固时间(TT)、活化部分凝血活酶时间(APTT)的动态变化。结果注入羊水后PT、TT、APTT时间显著延长(P<0.01),FIB则显著降低(P<0.01),而对照组无显著变化(P>0.05)。结论凝血指标的动态变化表明羊水栓塞早期有发生DIC的趋势,胎盘提取液中的某些成分可能加重了DIC的严重程度。     

Systemic Dissemination of Injected Foreign Material

A 32‐year‐old woman collapsed following an intravenous injection of material that included crushed pharmaceutical tablets. Resuscitation was attempted but was unsuccessful. She had an extensive past medical history of complications resulting from intravenous drug use. Death was due to mixed drug toxicity. The major findings at autopsy included a 10 mm deep skin sinus over the right femoral vein that was used as an injection site. Polarizable foreign material was present at the injection site and also within the lungs with a granulomatous reaction. Of note, a probe‐patent foramen ovale had permitted paradoxical embolization of this material into the systemic circulation with lodgement within the liver, portal lymph nodes, myocardium, spleen, kidneys, and pancreas. This case highlights the importance of checking for any intracardiac shunts, which may be quite small, and systemic dissemination of foreign material to multiple organs in intravenous drug users who present for medicolegal assessment.     

Intravascular bullet embolism to the right atrium

Bullet embolism is a relatively unusual complication of gunshot wounds. Embolism to the right atrium comprises <5% of all reported intravascular bullet emboli. We report an additional case of bullet embolus to the right atrium of a 0.38-caliber bullet following a gunshot wound to the chest. The intracardiac bullet was recognized radiologically on presentation, but the patient was hemodynamically stable and managed conservatively, with the bullet left in place. The missile remained within the heart without clinical significance for several years and was recovered from the right atrium only at the time of autopsy. To the best of our knowledge, this is the first documented case of a 0.38-caliber bullet which embolized to the right atrium and remained inconsequential for an extended period of time.     

家兔肺脂肪栓塞后超微病理学观察

目的 研究脂肪栓塞后肺组织的超微结构变化.方法 通过向实验组家兔血管内注射脂肪诱导肺脂肪栓塞制作肺栓塞动物模型,分别于栓塞即刻(0 h)和栓塞后3、8 h及1、2、7、14d处死动物;对照组家兔注射同等剂量的生理盐水,其余处理方法与实验组相同.经HE和苏丹Ⅲ染色证实造模成功后,用透射电镜观察肺组织的超微结构变化.结果 ...     

Fatal Acute Hemorrhagic Bowel Infarction Caused by Mesenteric Venous Thrombosis

Acute mesenteric venous thrombosis (MVT) is a rare, but life‐threatening medical phenomenon. MVT is normally characterized by insidious onset, with nonspecific signs and symptoms. A high index of clinical suspicion is required for diagnosis, and emergency surgery is necessary to optimize the chances of patient survival, especially in the people aged more than 70 years. Surprisingly, based on my review of the literature, no fatal acute MVT case has been reported in the forensic literature. All reported such cases have been documented in medical literature, and most of them have been associated with underlying risk factors for venous thrombosis, such as hypercoagulable state, certain cancers, and stasis of the blood flow. Here, I report the case of a sudden unexpected death due to extensive intestinal ischemia and infarction with massive abdominal hemorrhage caused by acute MVT in a 72‐year‐old man without known underlying risk factors.     

脂肪栓塞综合征的法医学研究进展

脂肪栓塞综合征（fat embolism syndrome,FES）是一种较多见而又威胁生命的临床症候。多年来,FES一直是医学界,尤其是法医学及骨科学领域研究的难点。在法医学中,FES的鉴定因缺乏典型的症状、体征,极易发生误鉴或漏鉴。本文就FES的病因、发病机理、病理学、致死机制以及FES的最新法医学诊断研究进行了回顾。     

大鼠实验性肺脂肪栓塞的病理学研究

取大鼠皮下脂肪乳化后作自身静脉注射,观察自身脂肪栓子对肺血管的光镜和电镜变化。结果表明,注射后1天肺小动脉及毛细血管内充满大量脂滴。4天时达高峰并伴有肺水肿、灶性出血以及单核细胞吞噬脂滴,中性、嗜酸性白细胞的浸润。7天后脂滴逐渐消失、未见其他脏器栓塞。     

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.     

A Minimally Invasive Technique for the Detection and Analysis of Pulmonary Fat Embolism: A Feasibility Study*

We investigated the feasibility of postmortem percutaneous needle biopsy (PNB) for obtaining pulmonary samples adequate for the study of pulmonary fat embolism (PFE). Samples of both lungs were obtained from 26 cadavers via two different methods: (i) PNB and (ii) the double-edged knife technique, the gold standard at our institute. After water storage and Sudan III staining, six forensic pathologists independently examined all samples for the presence and severity of PFE. The results were compared and analyzed in each case regarding the vitality of the PFE and its relationship to the cause of death. The results showed that PFE was almost identically diagnosed and graded on the samples obtained via both methods. The discrepancies between the two techniques did not affect the diagnoses of vitality or cause of death related to PFE. This study demonstrates the feasibility of the PNB sampling method for the diagnosis and interpretation of PFE in the postmortem setting.