Differential formation of a bioactive antiaggregating substance (BAS) by layers of the vein wall

Platelets ◽  
1997 ◽  
Vol 8 (2) ◽  
pp. 143-146
Author(s):  
E. I. Bermejo ◽  
A. C. Kempfer ◽  
M. Narbaitz ◽  
J. P. Frontroth ◽  
M. A. Lazzari
Keyword(s):  
Author(s):  
Н.Н. Петрищев ◽  
Д.Ю. Семенов ◽  
А.Ю. Цибин ◽  
Г.Ю. Юкина ◽  
А.Е. Беркович ◽  
...  

The purpose. In the study we investigated the impact of the partial blood flow shutdown on structural changes in the rabbit vena cava posterior wall after exposure to high-intensity focused ultrasound (HIFU). Methods. Ultrasound Exposure: frequency of 1.65 MHz, the ultrasound intensity in the focus of 13.6 kW/cm, the area of the focal spot 1 mm, continuous ultrasound, exposure for 3 seconds. Results. Immediately after HIFU exposure all layers of the vein wall showed characteristic signs of thermal damage. A week after exposure structural changes in the intima, media and adventitia was minimal in the part of vessel with preserved blood flow, and after 4 weeks the changes were not revealed. A week after HIFU exposure partial endothelium destruction, destruction of myocytes, disorganization and consolidation of collagen fibers of the adventitia were observed in an isolated segment of the vessel, and in 4 weeks endothelium restored and signs of damage in media and adventitia persisted, but were less obvious than in a week after exposure. Conclusion. The shutdown of blood flow after exposure to HIFU promotes persistent changes in the vein wall. Vein compression appears to be necessary for the obliteration of the vessel, when using HIFU-technology.


Platelets ◽  
1997 ◽  
Vol 8 (2) ◽  
pp. 143-146
Author(s):  
E.I. Bermejo ◽  
A.C. Kempfer ◽  
M. Narbaitz ◽  
J. P. Frontroth ◽  
M.A. Lazzari
Keyword(s):  

1990 ◽  
Vol 5 (2) ◽  
pp. 77-83 ◽  
Author(s):  
H. J. Scott

The pathogenesis of the development of varicose veins remains obscure, and there have been many theories suggesting the primary cause. Recognized predisposing factors include age, sex, race, weight, height, pregnancy, diet, erect stance, clothes, alcohol, heredity, bowel habit and occupation. However the primary causative factors have centred around vein wall weaknesses, valvular deficiencies, and haemodynamic effects. This review looks at the evidence for and against arteriovenous anastomoses being the initiating factor in the development of varicose veins.


2021 ◽  
pp. 112972982110090
Author(s):  
Nicholas Mielke ◽  
Steven Johnson ◽  
Patrick Karabon ◽  
Amit Bahl

Objective: Thrombophlebitis associated with peripheral intravenous catheters (PIVCs) is a poorly described complication in the literature. Given limited accuracy of current assessment tools and poor documentation in the medical record, the true incidence and relevance of this complication is misrepresented. We aimed to identify risk factors in the development of thrombophlebitis using an objective methodology coupling serial diagnostic ultrasound and clinical assessment. Methods: We conducted a single-site, prospective observational cohort study. Adult patients presenting to the emergency department that underwent traditionally placed PIVC insertion and were being hospitalized with an anticipated length of stay greater than 2 days were eligible participants. Using serial, daily ultrasound evaluations and clinical assessments via the phlebitis scale, we identified patients with asymptomatic and symptomatic thrombosis. The primary goal was to identify demographic, clinical, and IV related risk factors associated with thrombophlebitis. Univariate and multivariate analyses were employed to identify risk factors for thrombophlebitis. Results: A total of 62 PIVCs were included between July and August 2020. About 54 (87.10%) developed catheter-related thrombosis with 22 (40.74%) of the thrombosed catheters were characterized as symptomatic. Multivariate cox regression demonstrated that catheter diameter relative to vein diameter greater than one-third [AHR = 5.41 (1.91, 15.4) p = 0.0015] and angle of distal tip of catheter against vein wall ⩾5° [AHR = 4.39 (1.39, 13.8) p = 0.0116] were associated with increased likelihood of thrombophlebitis. Conclusions: Our study found that the increased proportion of catheter relative to vein size and steeper catheter tip angle increased the risk of thrombophlebitis. Catheter size relative to vein size is a modifiable factor that should be considered when inserting PIVCs. Additional larger prospective investigations using objective methodologies are needed to further characterize complications in PIVCs.


Vascular ◽  
2021 ◽  
pp. 170853812199012
Author(s):  
Yingfeng Wu ◽  
Libing Wei ◽  
Xixiang Gao ◽  
Yixia Qi ◽  
Zhu Tong ◽  
...  

Background The main cause of severe chronic venous insufficiency is deep venous incompetence. Deep venous reconstructive surgeries are reserved for cases that do not show a good response to conservative therapies. Method We present the case of a 68-year-old man presenting with swelling, pain, and pigmentation in his left lower limb for 14 years and ulcers for 10 years. Descending venography identified a Kistner’s grade IV reflux in the deep vein of the left lower limb. Internal valvuloplasty was performed following Kistner’s method. Meanwhile, external wrapping with a 1-cm-wide polyester-urethane vascular patch was performed to strengthen the vein wall in the venospasm condition. Results Symptoms were immediately relieved postoperatively. Refractory ulcers healed five months after the procedure. At the six-month follow-up, color duplex ultrasound of the deep vein of the left lower limb showed no reflux in the proximal segment of the femoral vein. Conclusion Internal valvuloplasty combined with sleeve wrapping is feasible in the treatment of severe deep venous incompetence with good short-term results.


2011 ◽  
Vol 51 ◽  
pp. S36
Author(s):  
Anuli Caroline Anyanwu ◽  
Hui Liao ◽  
Keigo Fukase ◽  
Timothy P. Quinn ◽  
Martin M. Gruca ◽  
...  

Author(s):  
Дина Владимировна Кривоносова ◽  
Евгений Сергеевич Ермолаев

На сегодняшний день в России для лечения варикозного расширения вен часто проводятся малоинвазивные операции методами радиочастотной или лазерной облитерации, при этом метод паровой облитерации при лечении варикозной болезни не применяется совсем. Однако метод паровой облитерации обладает существенными преимуществами: малый объём и биоинертность рабочей среды - водяного пара, его невысокая температура - 120 °С, исключающая вероятность образования нагара и перфорации венозной стенки. Целью данной работы является разработка математической модели для расчёта тепловых характеристик блока нагревания, входящего в устройство для лечения варикозной болезни методом паровой облитерации. Модель описывает теплообменные процессы в гидравлической трубке блока нагревания и может быть полезна при расчёте размеров нагревательного элемента, обеспечивающих нагрев и парообразование определённой порции воды. С целью верификации математической модели результаты моделирования были сопоставлены с экспериментальными данными. Была проведена серия экспериментов, в ходе которых были получены значения энергии, содержащейся в одной инжекции пара, и объём воды в одной инжекции, а также оценена фактическая тепловая мощность нагревателя. Сравнение результатов имитационного моделирования и значения фактической тепловой мощности пара, полученной экспериментальным путем, показала работоспособность математической модели. Разработанная математическая модель позволяет подбирать геометрические параметры нагревательного элемента в зависимости от требуемой тепловой мощности, которая должна быть обеспечена блоком нагревания, а также варьировать параметры нагревательного элемента для разной степени нагрева тканей Today in Russia minimally invasive varicose veins treatment is often performed using radiofrequency or laser ablation, while the method of steam ablation is not used at all. However, the steam ablation method has significant advantages: a small volume and biological inertness of the working substance - sterile water vapor, its low temperature - 120 °C, excluding the carbon deposits and perforation of the vein wall. The purpose of this work is to develop a mathematical model for calculating the thermal characteristics of the heating module as a part of the device for varicose veins treatment using steam ablation. The model describes heat exchange processes in the hydraulic circuit of the heating module and can be applied to calculate the dimensions of the heating module which provides heating and vaporization of a certain portion of water. In order to verify the mathematical model, the simulation results were compared with experimental data. A series of experiments were carried out in which the energy contained in one steam injection and the volume of water in one injection were estimated, as well as the actual thermal power of the heating module. Comparison of the results of simulation and the value of the actual thermal power of steam obtained experimentally showed the efficiency of the mathematical model. The proposed mathematical model allows to select the geometric parameters of the heating element depending on the required thermal power, which must be provided by the heating module, and also to vary the parameters of the heating element for different degrees of tissue heating


Author(s):  
F. Kh. Nizamov

Introduction. COVID-19 infection raises many questions regarding the health condition of patients after they have had COVID-19. The aim of this study is to examine the characteristic symptoms of chronic venous insufficiency in the postcovid period.Materials and methods. The materials that were used for work included the results of studying the medical aid appealability, characteristic symptoms, diagnosis and treatment of symptoms of chronic venous insufficiency in persons who have had the coronavirus infection. 47 patients presented with complaints about deterioration of their condition after they had had COVID-19 over March to September 2021 period. Methods: general clinical examiniation, ultrasound angioscanning of veins of the lower extremities, laboratory coagulation tests.Results and discussion. Before deterioration, calf circumference was measured 22–24 cm at a typical measurement site in most patients (89%), after covid infection it reached 26–27 cm. Varicose veins remained soft, without intravascular formations, edema was often bilateral, asymmetric, pain was described as constant (5–6 VAS scores), patients had prominent signs of lymphostasis. 35 out of 47 people received diosmin-based venotonic drug of Russian manufacture at a dose of 1000 mg/day (one tablet twice a day), the course of treatment lasted one to two months. After that period, the edema subsided in 85% of patients, the severity of pain syndrome significantly reduced (up to 2–3 VAS scores). With regard to chronic venous insufficiency in patients with chronic diseases of lower extremity veins (mostly varicose and post-thrombotic diseases), the significant progress of disease was observed in almost 94% of follow-up cases. Diosmin is the main drug that is prescribed to treat chronic venous insufficiency. The drug has an angioprotective and venotonic effect, reduces the vein wall elasticity, increases venous tone, and decreases venous stasis, reduces capillary permeability and fragility, and increases their resistance, improves microcirculation and lymphatic drainage.Сonclusions. In the postcovid period, clinical symptoms of some chronic diseases occur/worsen, including clinical manifestations of chronic venous insufficiency. The use of Russian diosmin-based drug for the management of edema and pain syndrome is very promising.


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