Venae cavae

If it is not dissolved or trapped, an embolism moving from the lower extremities can be life-threatening. People afflicted with phlebitis are particularly susceptible to this problem. A shape-memory trap has been devised that, when deployed in the vena cava, is like a multileaved mesh that traps a traveling embolism, retaining it until medication can dissolve it. Introduced in a folded form by a catheter, the mesh is prevented from deploying by subjecting it to a flow of cold saline water. Once in place, it is released from the catheter and, warmed by body heat, opens into its final shape (11). 

Hohlimg, /. cavity, hoUew, excavation. Hohl-vene, /. (Anat.) vena cava, -walze, /. hollow cylinder or roll, -welle, /. hollow shaft, -zahn, m. (Bot.) hemp nettle, -ziegel, m. hollow brick (or tile), -zirkel, m. inside calipers, -zylinder, m. hollow cylinder. 

Watanabe M, Shin oka T, Tohyama S, et al. Tissue-engineered vascular autograft Inferior vena cava replacement in a dog model. Tissue Eng, 2001, 7, 429 39. 

Large free-floating clot loosely attached to the inferior vena cava wall... 

Central venous (superior vena cava) or mixed venous oxygen saturation >70%... 

Inferior vena cava (IVC) interruption is indicated in patients with PE who have a contraindication to anticoagulation therapy... 

The primary goal of treatment of superior vena cava (SVC) syndrome is to relieve obstruction of the superior vena cava by treating the underlying malignancy. 

The superior vena cava (SVC) is the primary drainage vein for blood return from the head, neck, and upper extremities. It is a relatively thin-walled vein that is particularly vulnerable to obstruction from adjacent tumor invasion or thrombosis. The obstruction leads to elevated venous pressure, although collateral veins partially compensate. This is one reason for the relatively slow onset of the classic symptoms of SVCS. In fact, 75% of patients have signs and symptoms for more than 1 week before seeking medical attention.15... 

TABLE 96-6. Tumors Most Commonly Associated with Superior Vena Cava Syndrome... 

Wudel LJ, Nesbitt JC. Superior vena cava syndrome. Curr Treat Options Oncol 2001 2 77-91. 

PN can be administered via a smaller peripheral vein (e.g., cephalic or basilic vein) or via a larger central vein (e.g., superior vena cava). Peripheral PN (PPN) is infused via a peripheral vein and generally is reserved for short-term administration (up to 7 days) when central venous access is not available. PN formulations are hypertonic, and infusion via a peripheral vein can cause thrombophlebitis. Factors that increase the risk of phlebitis include high solution osmolarity, extreme pH, rapid infusion rate, vein properties, catheter material, and infusion time via the same vein.20 The osmolarity of PPN admixtures should be limited to 900 mOsm/L or less to minimize the risk of phlebitis. The approximate osmolarity of a PN admixture can be calculated from the osmolarities of individual components ... 

Central PN refers to the administration of PN via a large central vein, and the catheter tip must be positioned in the vena cava. Central PN allows the infusion of a highly concentrated, hypertonic nutrient admixture. The typical osmolarity of a central PN admixture is about 1500 to 2000 mOsm/L. Central veins have much higher blood flow, and the PN admixture is diluted rapidly on infusion, so phlebitis is usually not a concern. Patients who require PN administration for longer periods of time (greater than 7 days) should receive central PN. One limitation of central PN is the need for placement of a central venous catheter and an x-ray to confirm placement of the catheter tip. Central venous catheter placement may be associated with complications, including pneumothorax, arterial injury, air embolus, venous thrombosis, infection, chylothorax, and brachial plexus injury.1,20... 

HCTZ Hydrochlorothiazide IVC Inferior vena cava intravenous cholangiogram... 

SVC Superior vena cava VSS Vital signs stable... 

Retroperitoneal fibrosis An accumulation of fibrotic tissues in the retroperitoneum (the anatomic space behind the abdominal cavity). Structures that lie behind the peritoneum are thus termed retroperitoneal. These structures include kidneys, the bladder, portions of the duodenum, portions of the colon, and the inferior vena cava. 

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