The internal jugular vein exits the skull base from the jugular foramen collecting blood from the sigmoid sinus. However, when ultrasound guidance is not feasible, CVLs may be placed using anatomical landmarks without ultrasound. Ultrasound guidance can benefit all approaches and is recommended for every CVL placement. The subclavian vein approach is at higher risk for pneumothorax than the internal jugular vein approach. The femoral veins are compressible sites and, as such, may be more appropriate for patients who are at high risk of bleeding. The right internal jugular and subclavian valves are the most direct paths to the right atrium via the superior vena cava. There are three possible sites for CVL placement in adult patients: namely, the internal jugular, femoral, and subclavian. This article will detail the anatomy of the site placement, indications and contraindications, equipment and personnel involved, technique, preparation, and associated complications. With ultrasound guidance, standardized techniques, new catheter designs, and central line care bundle, this procedure has become ubiquitous in the intensive care unit. Over the past decade, there has been tremendous improvement and reduced complications associated with central line placement procedures. According to epidemiologic data, 8% of hospitalized patients require central venous access, and more than 5 million central venous catheters are inserted in the United States annually. ![]() Central line placement is an essential skill, especially in critical care units. Now referred to as the Seldinger technique, this procedure allows the safe and reliable insertion of a central venous catheter in the large lumen central veins. ![]() Sven-Ivar Seldinger, in 1953 introduced the method to facilitate catheter placement into the central veins lumens. For graphic design work it is almost never worthwhile to upsize an image more than about 10%.A central venous line (CVL) is a large-bore central venous catheter placed using a sterile technique (unless an urgent clinical scenario prevents sterile technique placement) in specific clinical procedures. There is a limit to how far you can scale any image before the result becomes too fuzzy to be useful, and the definition of what is useful depends entirely on your application. My experience is that the best approach varies according to the image, the amount of upsizing and the result you're looking for. ![]() This takes patience and a lot of trial and error to make it work for any give image, so I don't recommend it except in extreme cases, but once in a while it will allow you to push enlargement beyond where you can go without that intermediate sharpen. ![]() Sometimes you can get a better result if you increase the size by a smaller amount, apply a sharpen (not too much!), then increase it some more, apply another sharpen, etc., until you reach the size you want. In general, enlarge the image using Bicubic interpolation (sometimes, depending on the image, "Bicubic Smoother" works better, but usually straight Bicubic is more satisfactory), then either use Smart Sharpen to bring back the edge contrast, or copy the layer, set the blend mode of the copy to Overlay, and run Filter > Other > High Pass.
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