Thrombosis and thromboembolism: Brighton collaboration case definition and guidelines for data collection,analysis, and presentation of immunization safety data

This is a Brighton Collaboration case definition of thrombosis and thromboembolism to be used in the evaluation of adverse events following immunization, and for epidemiologic studies for the assessment of background incidence or hypothesis testing. The case definition was developed by a group of experts convened by the Coalition for Epidemic Preparedness Innovations (CEPI) in the context of active development of SARS-CoV-2 vaccines. The case definition format of the Brighton Collaboration was followed to develop a consensus definition and defined levels of certainty, after an exhaustive review of the literature and expert consultation. The document underwent peer review by the Brighton Collaboration Network and by selected expert reviewers prior to submission.     

The effect of ChAdOx1 nCov-19 vaccine on arterial thrombosis development and platelet aggregation in female rats

ChAdOx1 nCoV-19 adenoviral vector vaccine (ChAd) against coronavirus disease 2019 has been associated with vaccine-induced thrombosis and thrombocytopenia (VITT), especially in young women who have presented with unusual localized thrombosis after receiving the vaccine. The pathogenesis of VITT remains incompletely understood. We tried to provide new insights into mechanisms underlying this phenomenon in the model of arterial thrombosis electrically induced in the carotid artery of female rats. At 28 days post-vaccination, ChAd induced SARS-CoV-2-specific neutralizing antibody responses in all animals. The analysis of the blood vessel/thrombus area showed slight luminal narrowing of the carotid artery with extravasation of blood in vaccinated rats. These small changes were not accompanied by differences in thrombus weight and composition. The vaccinated animals presented a slight increase (by around 14–24%) in platelet aggregation. ChAd did not significantly affect blood coagulation, platelet counts, and their activation markers. Unaffected thrombus formation, the lack of thrombocytopenia and all the measured blood and hemostasis parameters that predominantly stayed unchanged, indicate that the ChAd does not increase the risk of arterial thrombosis development in female rats.     

置管溶栓与机械吸栓治疗急性下肢动脉血栓的安全性与疗效比较

目的:比较机械吸栓(PMT)与置管溶栓(CDT)治疗急性下肢动脉血栓的安全性与临床疗效。方法:回顾性分析2015年7月—2018年3月因急性下肢动脉血栓形成接受腔内介入治疗的67例患者的临床资料。其中37例行PMT治疗(PMT组),30例行CDT治疗(CDT组),比较两组的围手术期相关指标。结果:两组患者术前指标、术后需进一步行球囊扩张+支架植入的患者例数、一期血管开通率以及12个月一期血管通畅率均无统计学差异(均P0.05)。PMT组平均住院时间明显低于CDT组[(5.8±0.8)d vs.(8.9±0.6)d,P0.05],但平均住院费用高于CDT组[(7.0±1.1)万元vs.(4.8±0.8)万元,P0.05]。两组患者术后严重出血、术后截肢、穿刺处血肿、穿刺处感染、肾功能不全发生率均无统计学差异(均P0.05),但PMT组术后总并发症发生率明显低于CDT组(5.4%vs. 26.7%,P0.05)。结论:PMT与CDT在治疗急性下肢动脉血栓方面同样是安全、有效的。PMT相对于CDT术后总并发症发生率和住院时间减少,但住院费用增加。     

Coronary thrombo-embolic events after Covid-19 vaccination- a single centre study

Thrombo-embolic complications after Corona virus disease-19 (COVID-19) vaccination have been previously reported. We aimed to study the coronary thrombo-embolic complications (CTE) after COVID-19 vaccination in a single centre during the initial 3 months of vaccination drive in India. All patients admitted to our hospital between 1st March 2021 and 31st May 2021 with Acute coronary syndrome (ACS) were included.Of the 89 patients [Age 55 (47–64)y, 13f] with ACS and angiographic evidence of coronary thrombus, 37 (42%) had prior vaccination history. The timing from last vaccination dose to index event was <1, 1–2, 2–4 and >4 weeks in 9(24%), 4(11%), 15(41%) and 9 (24%) respectively. ChAdOx1 nCoV-19/AZD1222 (Covishield) was the most used vaccine- 28 (76%), while 9 (24%) had BBV152 (Covaxin). Baseline characteristics were similar in both vaccinated (VG) and non-vaccinated group (NVG), except for symptom to door time [8.5 (5.75–14) vs 14.5 (7.25–24) hrs, p = 0.003]. Thrombocytopenia was not noted in any of the VG patients, while 2 (3.8%) of NVG patient had thrombocytopenia (p = 0.51). The pre- Percutaneous Coronary Intervention (PCI) Thrombolysis in Myocardial Infarction (TIMI) flow was significantly lower [1 (0–3) vs2 (1–3), p = 0.03) and thrombus grade were significantly higher [4 (2.5–5) vs 2 (1–3), p = 0.0005] in VG. The in-hospital (2.7% vs 1.9%, p = 1.0) and 30-day mortality were also similar (5.4% vs 5.8%, p = 1.0).This is the first report of CTE after COVID-19 vaccination during the first 3 months of vaccination drive in India. We need further reports to identify the incidence of this rare but serious adverse events following COVID-19 vaccination.     

下肢静脉曲张术后并发静脉血栓的有效护理干预

目的:分析对下肢静脉曲张术后并发静脉血栓患者的有效护理干预措施。方法:以2019年6月~2019年6月我院收治的42例下肢静脉曲张患者为研究对象,随机分为两组,各21例,对照组常规护理,实验组实施有效护理干预,对比护理效果。结果:对照组下肢静脉曲张术后患者的并发深静脉血栓发生率高于实验组患者,差异具备统计学价值;实验组下肢静脉曲张术后患者的护理满意度高于对照组患者,差异显著且具备统计学意义。结论:下肢静脉曲张术后实施有效护理干预可降低并发静脉血栓发生率,同时提升患者护理满意度,有效改善患者预后,促进患者康复,也有利于维护良好的护患关系,因此应在临床实践中对有效护理干预进行推广与普及。     

Clinico-radiological profile of CVT patients and its correlation with D-dimer

Cerebral Venous Thrombosis (CVT) is a well-known disease with diverse clinical presentation and causes. With advances in neuroimaging and changing lifestyles, the clinical profile and causes of CVT are changing. D-dimer has been studied in early diagnosis of CVT with variable results. This prospective study was carried out to assess the clinical profile of CVT and role of D-dimer in early diagnosis of CVT. The study period was from September 2017 to July 2019 and included 32 imaging proven patients of CVT. We also included 32 patients of migraine for assessing D-dimer. Data was collected according to a preformed format. D-dimer was assessed by a rapid semi-quantitative latex agglutination assay. Out of 32 CVT patients, 16(50%) were females. The mean age of the patients was 31.56 ± 14.31 years. Most common clinical features were headache (96.25%), papilloedema (37.5%) and seizures 10 (31.25%). Puerperium was the most common cause of CVT in females. Superior sagittal and transverse sinuses were the most common sinuses to be affected. The sensitivity of D-dimer assay was 81.25% and specificity 62.5%. Cerebral venous thrombosis is a disease with equal predilection among both genders affecting mostly young individuals. Most of the patients present with headache. Puerperium still contributes to majority of the cases. Iron deficiency anaemia needs to be evaluated as an association for CVT. Positive D-dimer should strengthen the suspicion of CVT in patients with acute headache.     

一种氯化铁诱导血栓生成的小鼠大脑中动脉远端缺血模型

目的 建立稳定的小鼠大脑中动脉远端氯化铁血栓模型，评价其造成的脑损伤及神经功能损伤程 度。 方法 C57BL6/J雄性小鼠随机分为脑缺血组和假手术组。脑缺血组用10%氯化铁（ferric chloride， FeCl3）溶液诱导右侧大脑中动脉远端形成血栓。在术前、术后10 mi n、术后1 d和7 d观测术侧脑血流 和手术动脉血流量的变化。术后1 d观察脑组织梗死率。术后1 d、3 d、5 d、7 d用3种神经学评分[改良 加西亚评分（modified Garcia score，mGS）、改良神经损伤严重程度评分（modified neurological severity scores，mNSS）和15分神经学评估表（15-point neurological evaluation scale，NES）]和胶黏纸测试评价小 鼠神经功能。术后7 d免疫荧光染色标记神经细胞核观察脑组织损伤，标记CD16/32、CD206和Iba1观 察胶质细胞表达。 结果 与假手术组相比，脑缺血组术后10 mi n、1 d、7 d脑表面血流和手术动脉血流下降，术后1 d脑 皮层梗死明显，术后7 d仍有明显脑组织损伤；脑缺血组术后1 d、3 d、5 d和7 d时3种神经学评分及胶 黏纸测试均提示小鼠神经功能不同程度损伤。术后7 d脑缺血组梗死周围皮层M1和M2型胶质细胞表 达增加。 结论 FeCl3溶液可诱导形成稳定的小鼠脑缺血模型，该模型可造成手术侧大脑中动脉远端及脑表 面血流量降低，皮层脑梗死，小鼠神经功能受损，梗死周围胶质细胞表达上调。本研究建立了稳定 氯化铁诱导血栓形成的小鼠脑缺血模型，为脑血栓形成和抗栓药物治疗提供了一种可靠的研究工 具。