Abstract Introduction: Hemodynamic Depression (HD) characterized by hypotension and bradycardia is a complication of carotid surgery due to direct autonomic stimulation in the carotid sinus. The authors believe the incidence of HD is high and possibly related to major cardiac complications. Methods: Analysis of patient records during admissions for carotid surgery between January 2014 and December 2018 in two hospitals. HD was defined as bradycardia or hypotension in the first 24 postoperative hours. Bradycardia was defined as heart rate < 50bpm; hypotension as systolic blood pressure < 90 mmHg, continuous use of vasopressors, or a drop in SBP > 20% compared to preoperative values. Myocardial infarction, stroke, and cardiovascular death were defined as adverse events. Results: Overall, 237 carotid surgeries (178 endarterectomies, 59 angioplasties) were studied, and the global incidence of HD was 54.4% (hypotension in 50.2%, bradycardia in 11.0%, and hypotension and bradycardia in 6.8%). The independent predictors of HD were asymptomatic carotid stenosis (OR = 1.824; 95% CI 1.014 −3.280; p = 0.045), endovascular surgery (OR = 3.319; 95% CI 1.675−6.576; p = 0.001) and intraoperative hypotension or bradycardia (OR = 2.144; 95% CI 1.222−3.762; p = 0.008). Hypotension requiring continuous vasopressor infusion was the only factor independently associated with adverse cardiovascular events (OR = 5.504; 95% CI 1.729-17.529; p = 0.004). Discussion/conclusion: Incidence of Hemodynamic Depression after carotid surgery is high and independently associated with surgical technique, symptomatic repercussion of the carotid stenosis, and intraoperative hypotension or bradycardia. Hypotension requiring the continuous infusion of vasopressors was independently associated with the occurrence of MACE.

OBJECTIVES: The aim of this study was to analyze silicone tubes with an internal diameter of 4 mm as a possible material for vascular prostheses. METHODS: Grafts were implanted into the infrarenal aortas of 33 rabbits. Fluoroscopic examinations were performed within 150 days after surgical implantation. Sample grafts were analyzed via electron microscopy to evaluate the eventual endothelialization of the prostheses. RESULTS: The patency rates of the prostheses were 87% (±6.7%) after 30 days, 73% (±9.3%) after 60 days and 48% (±12%) after 120 days. The material presented characteristics that support surgical implantation: good tolerance promoted by polyester tear reinforcement, ease of postoperative removal and a lack of pseudoaneurysms. However, intimal hyperplasia was a limiting factor for the patency rate. CONCLUSIONS: We concluded that polydimethylsiloxane has limited potential as an alternative material for small vascular prostheses.

Resumo O acesso ao sistema venoso, seja para coleta de amostras de sangue ou para infusão de soluções, é de vital importância para o diagnóstico e tratamento de pacientes com as mais variadas condições clínicas. Desde que Harvey, em 1616, descreveu o sistema circulatório a partir de estudos em animais e que Sir Christopher Wren, 4 décadas depois, realizou a primeira infusão endovenosa em seres vivos, a evolução na técnica de acesso e nos dispositivos para infusão tem sido constante. Merece destaque a criação dos cateteres de longa duração na década de 1970, em especial os totalmente implantáveis, que revolucionaram o tratamento do câncer, aumentando a segurança e o conforto dos pacientes oncológicos. Este artigo tem como objetivo a revisão de dados históricos relativos ao acesso vascular e a discussão da técnica de implante e das principais complicações associadas ao procedimento de colocação e ao uso dos cateteres totalmente implantáveis.

Abstract Access to the venous system is of vital importance for diagnosis and treatment of patients with the most varied range of clinical conditions, whether for taking blood samples or for infusion of solutions. In 1616, Harvey described the circulatory system on the basis of studies in animals and 4 decades later Sir Christopher Wren conducted the first intravenous infusions in living beings. Since then there has been constant evolution in access technique and infusion devices. Of particular note is the creation of long-term catheters in the 1970s, particularly totally implantable devices, which revolutionized cancer treatment, increasing both safety and comfort for oncology patients. The objectives of this article are to review historical data on vascular access and discuss the implantation technique and the main complications associated with procedures for placement and use of totally implantable venous access devices.

OBJECTIVES: To analyze angiotomographic parameters of juxtarenal aneurysms to assess the applicability of an endograft model to patients and to create in vitro and in vivo models to assess the new endograft. METHODS: A total of 49 patients with juxtarenal aneurysms were submitted to angiotomographic evaluation, and parameters such as the aortic diameter, the length of the neck, and the angulations of the celiac trunk, superior mesenteric artery and renal arteries; the distances between them; and anatomic variations were analyzed. Based on these parameters, an endograft model was developed and tested in a newly created in vitro model of juxtarenal aneurysm. An experimental model of juxtarenal aneurysm was then established in six pigs weighing 50-60 kg to assess the new endograft model. RESULTS: The angiotomographic parameters of juxtarenal aneurysm measured in this study were similar to those reported in the literature and allowed the development of an endograft based on the hourglass concept, which was applicable to 85.8% of the patients. The in vitro model of juxtarenal aneurysm evidenced good radiopacity and functionality and permitted adjustments in the new device and technical improvements in the procedures for treating these aneurysms. In addition, the porcine model of juxtarenal aneurysm was successfully created in all six animals using a bovine pericardial patch, and use of the new endograft in three pilot procedures evidenced its feasibility. CONCLUSIONS: The Hourglass endograft was rendered applicable to treatment of the majority of patients with juxtarenal aneurysms simply by changing its diameter. Moreover, the new in vitro and in vivo models were shown to be effective for assessing both the presented endograft and experiments assessing the endovascular treatment of juxtarenal aneurysms.