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R Choux

Publications and source records attributed to R Choux.

106 records · Page 6Linked to original sources
PubMedDate not supplied

Experimental approach to prevention of catheter-related central venous thrombosis.

The role of catheter material in the formation of deep venous thrombosis during parenteral nutrition has been widely emphasized. Systematic venograms show central venous thrombosis in 20 to 33% of cases with polyethylene catheters and in 4% of cases with silicone catheters. Heparin infusion through the catheter diminishes but does not totally eliminate the risk of thrombosis. The aim of this study was to define the conditions under which the risk of thrombophlebitis was minimal. Four series of experiments were carried out, each on five rabbits. Catheters were inserted into the vena cava and, after 10 days, venograms were performed. The animals were then sacrificed, and the vena cava was macroscopically and microscopically studied. Plastic catheters were used in the first series, heparin-Benzalkonium-bonded plastic catheters in the second, silicone catheters in the third, and heparin-Benzalkonium-bonded silicone catheters in the fourth. The results revealed thrombosis of the vena cava and a fibrin sleeve around the catheters in series 1; thrombosis of the vena cava in series 2; a fibrin sleeve around the catheters in series 3; and neither thrombosis nor a fibrin sleeve in series 4. In conclusion, heparin-Benzalkonium-bonded silicone catheters appear to provide the best protection against thrombophlebitis by reducing the damage caused to the intima by the catheters and by slowing down platelet-aggregation around them.

Animals↗
PubMedDate not supplied

Mechanism of thrombogenesis during total parenteral nutrition: role of catheter composition.

Catheter material is considered as one of the main factors of deep venous thrombosis during parenteral nutrition. The effects of five types of catheters (polyethylene, polyurethane, silicone, TFE Teflon, and FEP Teflon) on the vein wall and on the blood flow were compared. Experiments were performed on rabbits in which catheters were inserted into the vena cava. Five series of experiments were performed, each including five animals with the same type of catheter. After 10 days, venograms of the vena cava were performed, animals were then killed and the vena cava was removed with the catheter in situ. The vein and the catheter were macroscopically examined; in cases with thrombosis the clot was weighed. The vein wall and the catheter were examined by conventional microscopy and by electron microscopy, respectively. Obstruction of the venous lumen were significantly more frequent with the rigid catheters than with the soft catheters (p less than 0.001). The most extensive thromboses occurred with the Teflon catheters. The incidence of fibrin sleeves was significantly higher with the soft catheters than with the rigid ones (p less than 0.01). The venographic and macroscopic findings were in agreement in 60-100% of the cases according to the degree of venous obstruction. Catheter surfaces remained unchanged in all cases. The polyethylene catheters induced the most severe intimal inflammatory reactions. Thrombus formation was caused by two mechanisms depending on catheter composition: (1) turbulence caused by the catheter in the blood stream, and (2) platelet aggregation and subsequently, fibrin deposition on the surface of the catheter.

Animals↗
PubMedDate not supplied

[Intraosseous meningioma in a child].

The authors present a case of intra-osseous meningioma in a 10 years old boy, located on the level of the vertex in the fronto-interparietal region, with the shape of a hand mass, painless, free from all neurological, ophtalmological and angiographic signs. The x-rays examination permit a diagnosis of an osteoma of the cranial vault. The surgery enables the exeresis of a large tumor of the vault 3 cm thick, without any attachment to the dura-matter. The histological examination reveals that it is, in fact, an intra-osseous meningioma. From this observation the authors carried out a review of all litterature in this field, only 12 observations are found again, and none of them deal with children. These intra-osseous meningioma develop from Pacchioni granulations included in the diploic region. They bring about handly any clinical signs and the x-rays findings do not enable us to put forward or suggest the diagnostic of intra-osseous meningioma.

Age Factors↗
PubMedDate not supplied

[Ultrastructural study of a Masson's "humid meningioma"].

The authors report the ultrastructural analysis of a Masson's humic meningioma. The tumor presents at the electronic microscopic examination every sign of secretive hyperactivity and does not show any degenerative characteristics. The existence of an important extracellular material rich in pre-collagenic fibres accounts for lacunar texture of this neoplasia at optic microscopic investigation; the role played by tumoral cells in the elaboration of the material is taken into account and seems to corroborate histogenic ecto-mesenchymatous theory of arachnoidal cells.

Capillaries↗
PubMedDate not supplied

[Bi-tissular malignant tumors of the lung. 2 cases].

Two new cases of multiple components pulmonary carcinoma are described: a pneumoblastoma and a epitheliosarcoma. Differenciating clinical features and nosological problems are recelled, allowing to discuss the classification of these two observations.

Aged↗
PubMedDate not supplied

[A new case of Urbach-Wiethe disease. Electron-microscopy study].

A new case of Urbach Wiethe disease is reported. The diagnosis of this disorder, despite the existence of typical histological connective tissue deposits, was recognized late. The authors review the morphological characteristics of the disease, emphasizing that atypical clinical presentations may occur which underline the importance of the histological examination.

Adult↗
PubMedDate not supplied

[Thoracoscopy in 1980. A general review (author's transl)].

Examining the literature and their own experience, the authors reviewed the methods, the complications and indications of modern thoracoscopy. They considered the rigid cold light thoracoscope with diathermo-coagulation. The authors stressed the importance of the macroscopic appearance of the pleural cavity, and the need to take numerous biopsies. Several types of anesthesia can be used, although the authors prefer general anesthesia for the comfort of both the patient and the doctor. Complications are very rare, the main ones being hemorrhage, pulmonary perforation and contamination of the puncture route with cancer cells. The first two can be avoided by good technique and diathermo-coagulation. The latter can be prevented by systematic radiotherapy of the puncture route, in mesothelioma patients. Amongst the numerous indications mentioned, three are important: the etiological diagnosis of chronic effusion, where cancer is a major fear. In these cases, the authors get 97% of positive results. Spontaneous pneumothorax is also a good indication: thoracoscopy allows a useful separation of patients, into those who need surgical treatment, or those in whom local adhesion of the pleura with talcum powder would be effective. Finally, pulmonary biopsy via the thoracoscope is a reliable and effective technique in a large number of indications.

Anesthesia↗