Subclavian vein

Chylomicrons are discharged from the enterocytes by exocytosis into lacteals, which are lymphatic vessels that originate in the intestinal villi, drain into the cisternae chyli, and follow a course through the thoracic ducts to enter the bloodstream through the left subclavian vein. 

Unlabeled Uses Acute peripheral occlusive disease, basilar artery occlusion, cerebral infarction, deep vein thrombosis, femoropopliteal artery occlusion, mesenteric or subclavian vein occlusion, pleural effusion (parapneumonic)... 

A 46-year-old woman with septic shock had a peripheral venous infusion of vasopressin 0.04 U/minute in addition to dobutamine, via the subclavian vein extravasation of vasopressin to local soft tissue resulted in ischemic skin necrosis (26). 

Right lymphatic duct opens into right subclavian vein of bloodstream... 

Chylomicrons are produced from dietary fat by the removal of resynthesised triglycerides from the mucosal cells of the small intestine into the intestinal lumen. These then enter the circulation via the thoracic dncts in the lymphatic system and enter into the subclavian veins, where triglyceride content is reduced by the action of lipoprotein lipases (LPL) on capillary endothelial surfaces in skeletal muscle and fat. The free fatty acids (FFA) from the triglycerides are used by the tissues as an energy source or stored as triglycerides. The chylomicron remnants, stripped of triglyceride and therefore denser, are then taken up by the liver by LDL receptor-mediated endocytosis, thereby delivering cholesterol to the liver. 

Coodley, E.L., Matsnmoto Thoracic duct-subclavian vein anastomosis in management of cirrhotic ascites. Amer. J. Med. Sci. 1980 279 163-168... 

Fracture of a central venous catheter due to compression between the clavicle and the adjacent first rib has been reported (5). A pinched-off sign on X-ray indicates the need to remove the catheter, because of a significant risk of subsequent fracture, which has an incidence of 0.9%. Catheters lying anterior to the subclavian vein between the clavicle and the first rib are hable to be compressed and to fracture subsequently. This is a potentially life-threatening complication that can be averted by correct placing of the central venous catheter and by immediate chest radiography to search for evidence of catheter kinking or compression. 

A 67-year-old woman was provided with a totally implantable venous device in the right subclavian vein by the Seldinger technique with a peel-away sheath. The device was used for a course of chemotherapy. After about 1 month there was subcutaneous extravasation of the drug. A chest X-ray showed that the sihcone catheter had fractured below the clavicle and the distal portion of the catheter had embolized into the right atrium. The fragments were removed. 

Gluszek S, Kot M, Matykiewicz J. Cardiac tamponade as a comphcation of catheterization of the subclavian vein— prevention and principles of management. Nutrition 1999 15(7-8) 580-2. 

Parenteral route, which provides high-calorie nutrients administered through large veins such as the subclavian vein. This process is called total parenteral nutrition (TPN) or hyperalimentation. Parenteral is expensive, has a high rate of infection, and does not promote GI function, liver function, or weight gain. 

Parenteral nutritional support therapy is a means of providing high caloric nutrients administered through large veins such as the subclavian vein. 

After its absorption into the intestinal mucosal cell, cholesterol, together with triglycerides, phospholipids, and a number of specific apoproteins, is assembled into a large lipoprotein called the chylomicron (see later section on lipoprotein metabolism, exogenous pathway). One apoprotein component known as apolipoprotein (apo) B-48 is vital to the formation of chylomicrons, and in people with a rare deficiency of apo B-48 synthesis, chylomicron formation, and consequently cholesterol and fat absorption, is severely impaired. Chylomicrons enter the lymphatics, which empty into the thoracic duct and eventually enter the systemic venous circulation at the junction of the left subclavian vein and left internal jugular vein. 

Chylomicrons are the largest of the lipoproteins and the least dense because of their rich triacylglycerol content. They are synthesized from dietary lipids (the exogenous lipoprotein pathway) within the epithelial cells of the small intestine and then secreted into the lymphatic vessels draining the gut (see Fig. 32.13). They enter the bloodstream via the left subclavian vein. The major apoproteins of chylomicrons are apoB-48, apoCn, and apoE (see Table 34.3). The apoCn activates lipoprotein lipase... 

In patients who are to undergo thrombolysis, care must be taken with attempts at instrumentation. An arterial puncture from attempted catheterization in a non-compressiblesite(e.g.,subclavian vein)iscontraindicated in patients to be treated with thrombolytic agents. 

The chylomicrons are stabilized by adsorbed lipoprotein and phospholipids. The lymph enters the bloodstream at the juncture of the thoracic duct and the subclavian vein. This dietary fat is largely removed from the blood by the cells of adipose tissue. 

Enteral nutritional support therapy introduces nutrition into the patient by mouth or a feeding tube that is directly inserted in the stomach or small intestine. Parenteral nutritional support therapy administers high caloric nutrients through large veins such as the subclavian vein. 

Chylomicrons enter the bloodstream via the thoracic duct that is part of the lymphatic system. The thoracic duct drains fluid from the mesentery of the small intestine and passes from the abdominal cavity, along the mediastinum in the thorax, into the subclavian vein near the neck. What are the metabolic consequences of this ronte of delivery into the blood ... 

When carbohydrates are absorbed from the intestine, they pass directly into the blood that drains via the portal vein to the liver, so it is the first major organ to gain access to these nutrients. The delivery of chylomicrons into the bloodstream in the subclavian vein, rather than into the portal vein, means that the first tissues to encounter chylomicrons are not the liver. Lipids in chylomicrons first encounter the other tissues such as the heart, skeletal muscle, and adipose tissue and these interact with other chylomicrons and lipoproteins in their/fraf pass through the blood circulation. This competition with the liver for first grab at the food supply, however, is unlikely to be a major factor in the overall distribution of fuel to cells. As the mean circulation time of blood in the human is only 1 min the chylomicron pool is rapidly distributed throughout the body. 

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