![]() ![]() ![]() The lumen of a normal, patent vein appears anechoic. Depth and gain are adjusted as previously described in Chapter 26, Lower Extremity Deep Venous Thrombosis. In two-dimensional mode, the transducer is placed transversely over the proximal upper extremity. When the operator is facing the patient as shown in Figure 27.2, the transducer is oriented with the marker pointing toward the operator’s left side (patient’s right side) to image veins in a transverse plane, except for the subclavian vein, which is imaged longitudinally below the clavicle. For superficial veins, the frequency can be increased to 10 MHz for better resolution of smaller vessels. B, The arm is abducted to 90 degrees, and the transducer is held with the marker pointed toward the patient’s right side.Ī high-frequency (5–12 MHz) linear transducer is used to scan all upper extremity vessels. The median cubital vein runs in the antecubital fossa between the cephalic and basilic veins.Ī, Positioning of the patient, operator, and ultrasound machine for performance of an upper extremity deep venous thrombosis ultrasound exam. The basilic vein runs along the medial aspect of the upper arm, pierces the deep fascia in the mid–upper arm, and joins the brachial vein to become the axillary vein in the axilla. The cephalic vein ascends along the lateral aspect of the biceps, turns medially into the deltopectoral groove, pierces the clavipectoral fascia below the clavicle, and merges with the upper axillary vein. The superficial veins do not have accompanying arteries. The main superficial veins of the upper extremities are the cephalic, basilic, and median cubital veins. The internal jugular vein is within the carotid sheath and travels from the jugular foramen in the base of the skull to behind the clavicle, where it fuses with the subclavian vein. The superficial veins are the cephalic, basilic, and median cubital veins (see also Figure 29.1 ).Īn ultrasound examination of the upper extremity veins is not complete without assessing the internal jugular vein, even though it is located in the neck. The major deep veins are the ulnar and radial veins in the forearm brachial veins in the upper arm axillary vein becoming the subclavian vein at the lateral border of the first rib the innominate vein (brachiocephalic vein) and the superior vena cava. ![]() Similarly, reported incidence of UEDVT associated with peripherally inserted catheters varies significantly, from 1.6% to as high as 27%.Īnatomy of the upper extremity venous system. In at least one study, the incidence of DVT associated with central venous catheters appears to be higher with subclavian vein rather than internal jugular vein catheters (13% vs. Reported incidence of UEDVT with indwelling catheters varies widely from 12% to 35%, with 75% of cases being asymptomatic. Despite the strong association of venous catheters, pacemaker wires, and infusion ports with thrombosis, few studies have been published about the pathophysiology of UEDVT. The perceived lower risk leads to fewer evaluations for DVT in upper extremities compared to lower extremities. The reported risk of pulmonary embolism is lower with UEDVT (2–17%) than with lower extremity DVT, although the actual prevalence of UEDVT is not known. Underdiagnosis is a concern given the frequent lack of symptoms with nonocclusive internal jugular vein or subclavian vein thrombosis. This chapter focuses on use of point-of-care ultrasound to diagnose upper extremity deep venous thrombosis (DVT), including examination technique, imaging protocols, and common pitfalls.Īnnual incidence of upper extremity DVT (UEDVT) is approximately 3.6/100,000, occurring predominantly in patients with malignancy, critical illness, obesity, and central venous catheters. Ultrasonography of the upper extremity venous system has wide applications, including evaluation for thrombus, guidance of venous catheter insertion, preoperative mapping for hemodialysis arteriovenous fistula or graft placement, and postoperative assessment of venous patency. ![]()
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