Curva de aprendizaje para ventana ecográfica de la vena cava inferior, en residentes de medicina de emergencias

INTRODUCCIÓN. El ultrasonido es fundamental en la medicina de emergencias, no se conoce cual debería ser la curva de aprendizaje para obtener las competencias técnicas y operativas; ACEP recomienda por cada ventana ecográfica realizar 25 repeticiones. No existe una curva de aprendizaje para ventana de VCI en la población de residentes colombianos. OBJETIVO: Determinar la curva de aprendizaje necesaria para obtener una proporción mayor al 80% de éxitos en la toma de la ventana ecográfica de la VCI, usando la escala de calificación para el aseguramiento de la calidad sugerida por ACEP, en residentes de I a III año de medicina de emergencias. METODOLOGÍA: Estudio experimental no comparativo, que evaluó la proporción de éxito en función del las tomas repetidas de la VCI por ultrasonido, mediciones que se tomaron luego de participar en una capacitación teórica y demostrativa de la técnica propuesta; se calificaron los videos según la escala publicada por ACEP. El análisis estadístico se realizó con un modelo logístico multinivel para la proporción del éxito, agrupado por repetición y agrupado por sujeto. RESULTADOS: Se obtuvo información de 8 residentes, cada uno realizo 25 repeticiones a 3 modelos sanos con asignación aleatoria. Se realizó la curva de aprendizaje obteniendo en 11 repeticiones una proporción de 0.80 (rango 0.54 a 0.92) y en 21 repeticiones una proporción de 0.9 (rango 0.75 a 0.96), datos ajustados por numero de repetición y residente. CONCLUSIÓN: La curva de aprendizaje para la ventana ecográfica de la VCI es de 11 y 21 repeticiones para obtener el 80% y 90% de éxito en residentes de medicina de emergencias de I a III año de la universidad del rosario.

Inferior vena cava syndrome due to Echinococcus multilocularis.

Alveolar echinococcosis is an invasive, tumor-like zoonosis, accidentally transmitted to humans. We present a case of recurrent inferior vena cava (IVC) syndrome due to alveolar echinococcosis and strongly suspected on transthoracic echocardiographic examination.

Long-term histopathologic evaluation of inferior vena cava after modified Greenfield filter implantation - Experimental study in sheep

Aim. The authors assess a modified Greenfield filter (GF) for the long-term patency, filter tilting and histopathologic alterations of the inferior vena cava (IVC).Methods. Adult sheep (n=7) underwent modified GF placement in the IVC. Cavograms were obtained every 3 months and pulmonary angiography at 12 months. Histopathologic and scanning electron microscopy (SEM) analyses were performed on the IVC explanted at 12 months.Results. Cavograms showed that all IVC were patent at the end of the study. Filter tilting occurred in 2/7 animals and extrusion of struts was not observed. Macroscopic examination at explantation showed minimal venous wall thickening. Microscopic examination showed minimal IVC fibrosis and intimal hyperplasia. SEM showed endothelium on the IVC surface at the filter implantation site and a presumed endothelial layer covering partially or totally the struts. The interface filter-IVC was covered by deposits of leucocytes and platelets. No signs of pulmonary embolism were found in all pulmonary angiograms of both groups.Conclusion. The modified filter presented good biocompatibility, stability and absence of thrombogenicity at 12 months. It presented low tendency to tilting and extrusion of struts. The long-term histopathologic alterations in vena caval wall were minimal and the appearance of the studied filters in the IVC was similar to stents placed in the arterial system.

Implante de filtro em veia cava inferior dupla: relato de caso e revisão da literatura

Veia cava inferior dupla é uma variação anatômica rara cuja prevalência é de 0,2-3%. O implante de filtro de veia cava, quando indicado em casos com duplicidade da veia cava inferior, pode ser realizado de diferentes formas: em ambas as veias cavas; em uma delas, embolizando a anastomose entre ambas; em somente uma delas; ou por implante supra-renal. Relatamos um caso de trombose venosa profunda no pós-operatório de implante de prótese de quadril com contra-indicação para tratamento anticoagulante e cuja cavografia evidenciou duplicidade de veia cava inferior. O implante de filtro de veia cava inferior realizado em posição supra-renal mostrou-se opção adequada e segura.

Ausência parcial de veia cava inferior associada à malformação intestinal

Criança de 6 anos de idade, sexo feminino, procurou serviço médico devido a mal-formação gastrointestinal. Durante o acompanhamento médico, foi diagnosticada ausência parcial de veia cava inferior, alteração congênita rara que envolve a drenagem vascular do segmento inferior do corpo. Realizados exames de imagem, os quais contribuíram para avaliação e descrição do caso. Mantido tratamento conservador com anticoagulante oral. Paciente apresenta boa evolução após longo tempo de acompanhamento cardiovascular.

Architecture of the caudal vena cava wall of the dog at the level of the liver caudate lobe

The vascular segment of the caudal vena cava of the dog at the level of the caudate lobe was shown to be intimately related to hepatic tissue through the hepatic capsule and parenchyma. The tunica adventitia of the caudal vena cava was formed mainly by smooth muscle cells with collagen and elastic fibers arranged in bundles. The thin tunica media of the vein was also formed by smooth muscle cells, collagen and elastic fibers arranged in bundles. The tunica intima presented an elastic sub-endothelial network. The hepatic segment of the caudal vena cava showed a myoconnective architecture and propulsive characteristics in terms of its hemodynamic pattern.

Involvement of the AT(1) receptor in the venoconstriction induced by angiotensin II in both the inferior vena cava and femoral vein

Although angiotensin II-induced venoconstriction has been demonstrated in the rat vena cava and femoral vein, the angiotensin II receptor subtypes (AT(1) or AT(2)) that mediate this phenomenon have not been precisely characterized. Therefore, the present study aimed to characterize the pharmacological receptors involved in the angiotensin II-induced constriction of rat venae cavae and femoral veins, as well as the opposing effects exerted by locally produced prostanoids and NO upon induction of these vasomotor responses. The obtained results suggest that both AT(1) and AT(2) angiotensin II receptors are expressed in both veins. Angiotensin II concentration-response curves were shifted toward the right by losartan but not by PD 123319 in both the vena cava and femoral vein. Moreover, it was observed that both 10(-5) M indomethacin and 10(-4) M L-NAME improve the angiotensin II responses in the vena cava and femoral vein. In conclusion, in the rat vena cava and femoral vein, angiotensin II stimulates AT(1) but not AT(2) to induce venoconstriction, which is blunted by vasodilator prostanoids and NO. (C) 2010 Elsevier Inc. All rights reserved.

Involvement of the AT1 receptor in the venoconstriction induced by angiotensin II in both the inferior vena cava and femoral vein

Although angiotensin II-induced venoconstriction has been demonstrated in the rat vena cava and femoral vein, the angiotensin II receptor subtypes (AT1 or AT2) that mediate this phenomenon have not been precisely characterized. Therefore, the present study aimed to characterize the pharmacological receptors involved in the angiotensin II-induced constriction of rat venae cavae and femoral veins, as well as the opposing effects exerted by locally produced prostanoids and NO upon induction of these vasomotorresponses. The obtained results suggest that both AT1 and AT2 angiotensin II receptors are expressed in both veins. Angiotensin II concentration–response curves were shifted toward the right by losartan but not by PD 123319 in both the vena cava and femoral vein. Moreover, it was observed that both 10−5 Mindomethacin and 10−4 M L-NAME improve the angiotensin II responses in the vena cava and femoral vein. In conclusion, in the rat vena cava and femoral vein, angiotensin II stimulates AT1 but not AT2 to induce venoconstriction, which is blunted by vasodilator prostanoids and NO.

Tumor thrombus of inferior vena cava in patients with renal cell carcinoma - clinical and oncological outcome of 50 patients after surgery

Background To evaluate oncological and clinical outcome in patients with renal cell carcinoma (RCC) and tumor thrombus involving inferior vena cava (IVC) treated with nephrectomy and thrombectomy. Methods We identified 50 patients with a median age of 65 years, who underwent radical surgical treatment for RCC and tumor thrombus of the IVC between 1997 and 2010. The charts were reviewed for pathological and surgical parameters, as well as complications and oncological outcome. Results The median follow-up was 26 months. In 21 patients (42%) distant metastases were already present at the time of surgery. All patients underwent radical nephrectomy, thrombectomy and lymph node dissection through a flank (15 patients/30%), thoracoabdominal (14 patients/28%) or midline abdominal approach (21 patients/42%), depending upon surgeon preference and upon the characteristics of tumor and associated thrombus. Extracorporal circulation with cardiopulmonary bypass (CPB) was performed in 10 patients (20%) with supradiaphragmal thrombus of IVC. Cancer-specific survival for the whole cohort at 5 years was 33.1%. Survival for the patients without distant metastasis at 5 years was 50.7%, whereas survival rate in the metastatic group at 5 years was 7.4%. Median survival of patients with metastatic disease was 16.4 months. On multivariate analysis lymph node invasion, distant metastasis and grading were independent prognostic factors. There was no statistically significant influence of level of the tumor thrombus on survival rate. Indeed, patients with supradiaphragmal tumor thrombus (n = 10) even had a better outcome (overall survival at 5 years of 58.33%) than the entire cohort. Conclusions An aggressive surgical approach is the most effective therapeutic option in patients with RCC and any level of tumor thrombus and offers a reasonable longterm survival. Due to good clinical and oncological outcome we prefer the use of CPB with extracorporal circulation in patients with supradiaphragmal tumor thrombus. Cytoreductive surgery appears to be beneficial for patients with metastatic disease, especially when consecutive therapy is performed. Although sample size of our study cohort is limited consistent with some other studies lymph node invasion, distant metastasis and grading seem to have prognostic value.

Treatment of superior vena cava (SVC) syndrome and inferior vena cava (IVC) thrombosis in a patient with colorectal cancer: combination of SVC stenting and IVC filter placement to palliate symptoms and pave the way for port implantation

Thrombosis of the inferior vena cava is a life-threatening complication in cancer patients leading to pulmonary embolism. These patients can also be affected by superior vena cava syndrome causing dyspnea followed by trunk or extremity swelling. We report the case of a 61-year-old female suffering from an extended colorectal tumor who became affected by both of the mentioned complications. Due to thrombus formation within the right vena jugularis interna, thrombosis of the inferior vena cava, and superior vena cava syndrome, a combined interventional procedure via a left jugular access with stenting of the superior vena cava and filter placement into the inferior vena cava was performed As a consequence, relief of the patient's symptoms, prevention of pulmonary embolism, and paving of the way for further venous chemotherapy were achieved.

Safety of inferior vena cava filter retrieval in anticoagulated patients

PURPOSES: To evaluate the safety of inferior vena cava (IVC) filter retrieval in therapeutically anticoagulated patients in comparison to prophylactically or not therapeutically anticoagulated patients with respect to retrieval-related hemorrhagic complications. MATERIALS AND METHODS: This was a retrospective study of 115 consecutive attempted IVC filter retrievals in 110 patients. Filter retrievals were stratified as performed in patients who were therapeutically anticoagulated (group 1), prophylactically anticoagulated (group 2), or not therapeutically anticoagulated (group 3). The collected data included anticoagulant and antiplatelet medications (type, form and duration of administration, dosage) at the time of retrieval. Phone interviews and chart review was performed for the international normalized ratio (INR), activated partial thromboplastin time, platelet count, infusion of blood products, and retrieval-related hemorrhagic complications. RESULTS: Group 1 included 65 attempted filter retrievals in 61 therapeutically anticoagulated patients by measured INR or dosing when receiving low-molecular-weight heparin (LMWH). Four retrievals were not successful. In patients receiving oral anticoagulation, the median INR was 2.35 (range, 2 to 8). Group 2 comprised 23 successful filter retrievals in 22 patients receiving a prophylactic dose of LMWH. Group 3 included 27 attempted filter retrievals in 27 patients not receiving therapeutic anticoagulation. Six retrievals were not successful. Five patients were receiving oral anticoagulation with a subtherapeutic INR (median, 1.49; range, 1.16 to 1.69). No anticoagulation medication was administered in 22 patients. In none of the groups were hemorrhagic complications related to the retrieval procedures identified. CONCLUSIONS: These results suggest that retrieval of vena cava filters in anticoagulated patients is safe. Interruption or reversal of anticoagulation for the retrieval of vena cava filters is not indicated.

Venous thromboembolism after retrieval of inferior vena cava filters

PURPOSE: To determine the incidence of venous thromboembolism (VTE) after removal of retrievable inferior vena cava (IVC) filters. MATERIALS AND METHODS: Retrospective study was conducted of 67 patients who underwent 72 consecutive filter retrievals at a single institution. Data collected included VTE status at the time of filter placement, anticoagulant medications at the time of filter retrieval and afterward, new or recurrent VTE after filter removal, and insertion of subsequent filters. Patient questionnaires were completed in 50 cases, chart review in all patients. RESULTS: At the time of filter placement, 30 patients had documented VTE, 19 had a history of treated VTE, and 23 were at risk for but had neither previous nor present VTE. Mean duration of follow-up after filter removal was 20.6 months +/- 10.9. A total of 52 patients (57 filters) received anticoagulation and/or antiplatelet medications after filter removal. There were two documented episodes of recurrent deep vein thrombosis (2.8% of filters removed), both in patients who had VTE at the time of filter placement and underwent therapeutic anticoagulation at the time of filter removal. One of these patients (1.4% of filters removed) also experienced pulmonary embolism. Of the 23 patients without VTE when the filter was placed, none developed VTE after filter removal. Four patients (5.5% of filters removed) required subsequent permanent filters, three for complications of anticoagulation, one for failure of anticoagulation. CONCLUSIONS: VTE was rare after removal of IVC filters, but was most likely to occur in patients who had VTE at the time of filter placement.

Low-grade endometrial stromal sarcoma with inferior vena cava tumor thrombus and intracardiac extension: radical resection may improve recurrence free survival

BACKGROUND: Endometrial stromal sarcoma (ESS) represents 0.2% of all uterine malignancies. Based on the mitotic activity, a distinction is made between low and high-grade ESS. Although the overall five-year survival rate for low-grade ESS exceeds 80%, about 50% of the patients show tumor recurrence, mostly after a long latency period. Tumor invasion of the great vessels is extremely rare. We describe a patient with advanced low-grade ESS with tumor invasion of the infrarenal aorta and the inferior vena cava. The patient presented with a large tumor thrombus extending from the inferior vena cava into the right atrium. METHODS: Review of literature and identification of 19 patients, including our own case report, with advanced low-grade ESS with invasion of the great vessels and formation of an inferior vena cava tumor thrombus. RESULTS: All 19 patients presented with an abdominal tumor mass and a tumor thrombus protruding into the inferior vena cava. The tumor thrombus extended into the right heart cavities in nine patients reaching the right atrium in four, the right ventricle in three and the pulmonary artery in two patients. There were 5 patients with an advanced primary tumor and 14 patients with an advanced recurrent tumor. Seven patients presented with synchronous metastatic disease and six patients with a pelvic tumor infiltrating the bladder, the rectosigmoid colon or the infrarenal aorta. Mean age at surgery was 45.9+/-12.3 years (median 47, range 25-65 years). Tumor thrombectomy was accomplished by cavatomy or by right atriotomy after installation of a cardiopulmonary bypass. There was no peri-operative mortality and a very low morbidity. Radical tumor resections were achieved in 10 patients. The follow-up for these 10 patients was 2+/-1.3 years (median 2, range 0.3-4.5 years). Nine patients remained recurrence free whereas one patient suffered an asymptomatic local recurrence. CONCLUSIONS: Low-grade ESS is a rare angioinvasive tumor with a high recurrence rate. Resection of an inferior vena cava tumor thrombus, even with extension into the right heart cavities, can be performed safely. Extensive radical surgery is therefore justified in the treatment of advanced tumor manifestations of a low-grade ESS potentially improving recurrence free survival.

Survival effects of inferior vena cava filter in patients with acute symptomatic venous thromboembolism and a significant bleeding risk.

OBJECTIVES The purpose of this study was to investigate the survival effects of inferior vena cava filters in patients with venous thromboembolism (VTE) who had a significant bleeding risk. BACKGROUND The effectiveness of inferior vena cava filter use among patients with acute symptomatic VTE and known significant bleeding risk remains unclear. METHODS In this prospective cohort study of patients with acute VTE identified from the RIETE (Computerized Registry of Patients With Venous Thromboembolism), we assessed the association between inferior vena cava filter insertion for known significant bleeding risk and the outcomes of all-cause mortality, pulmonary embolism (PE)-related mortality, and VTE rates through 30 days after the initiation of VTE treatment. Propensity score matching was used to adjust for the likelihood of receiving a filter. RESULTS Of the 40,142 eligible patients who had acute symptomatic VTE, 371 underwent filter placement because of known significant bleeding risk. A total of 344 patients treated with a filter were matched with 344 patients treated without a filter. Propensity score-matched pairs showed a nonsignificant trend toward lower risk of all-cause death for filter insertion compared with no insertion (6.6% vs. 10.2%; p = 0.12). The risk-adjusted PE-related mortality rate was lower for filter insertion than no insertion (1.7% vs. 4.9%; p = 0.03). Risk-adjusted recurrent VTE rates were higher for filter insertion than for no insertion (6.1% vs. 0.6%; p < 0.001). CONCLUSIONS In patients presenting with VTE and with a significant bleeding risk, inferior vena cava filter insertion compared with anticoagulant therapy was associated with a lower risk of PE-related death and a higher risk of recurrent VTE. However, study design limitations do not imply a causal relationship between filter insertion and outcome.