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PART 4 — PERIPHERAL VENOUS
The signs and symptoms of upper extremity ve- nous thrombosis are similar to those described for the lower extremity venous system. These can include unilateral arm or hand swelling, a superficial palpable cord, erythema, pain, and tenderness. Some patients may present with facial swelling or dilated chest wall venous collaterals, which could be suggestive of supe- rior vena cava thrombosis. Patients may present with indwelling catheters or a history of venous catheters.1,2
There may be patients presenting for an upper ex- tremity venous ultrasound who are asymptomatic. These may be patients in whom the central veins may be required to be examined prior to catheter placement or placement of pacemaker wires or other cardiac devices.
Upper extremity veins may also be examined in those patients with suspected pulmonary embolus. These patients may present with symptoms consis- tent with pulmonary embolus including chest pain, tachypnea, or tachycardia.
PATHOPHYSIOLOGY
The pathogenesis of upper extremity thrombosis, as in lower extremity venous thrombosis, can be found in the components of Virchow’s triad: namely, venous stasis, hypercoagulability, and vessel wall injury. Thrombosis in the upper extremity veins is now more common due to an increase in injury to the vein walls. Patients are having more frequent introduction of needles and cath- eters into arm veins. With few exceptions, whenever an individual has not had a venous puncture or cannula- tion, the incidence of upper extremity venous throm- bosis will be very low. This fact makes taking a history and selecting the proper indications for study of the up- per extremity veins with ultrasound much easier than with the legs. Because of the location of the subclavian and internal jugular veins, these veins are commonly used for indwelling catheters for feeding and drug ad- ministration as well as catheters used to monitor central venous pressure. Pacemaker wires are also introduced, usually through the subclavian vein, and are another common cause of upper extremity venous thrombosis.
Another type of venous catheter that can cause thrombosis is a peripherally inserted central catheter (PICC). A PICC line is not inserted into one of the large veins in the neck or shoulder region but rather via a pe- ripheral vein, often the basilic or cephalic veins. After it is inserted via one of these arm veins, the catheter is advanced to position the tip near the right atrium.
There are patients that present with upper extremity venous thrombosis without a history of venous punc- ture or cannulation. These patients include a unique group that present with upper extremity venous throm- bosis secondary to compression of the subclavian vein
at the thoracic inlet around the area of the first rib. It is thought to be the result of years of repetitive trauma and intermittent compression of the subclavian vein. This type of thrombosis is known as effort thrombosis or as Paget-Schroetter syndrome. The patients present- ing with this type of venous thrombosis are young, ath- letic, and muscular males but this syndrome can occur in other individuals as well.
SONOGRAPHIC EXAMINATION TECHNIQUES
The protocols described here are a summary of tried and true protocols that will produce accurate venous duplex ultrasound results.3–7 The compression tech- niques employed in the examination of the lower extremity veins are also performed for the upper ex- tremity veins. Using the ultrasound transducer, gentle compression is applied directly over the vein so that the walls of the vein coapt or close together. This compression maneuver is repeated every 2 to 3 cm along the course of each vein. Spectral Doppler wave- forms are recorded from all major vessels examined.
PATIENT PREPARATION
The examination should be explained to the patient. The patient signs and symptoms, along with relevant history, should be obtained. Upper extremity cloth- ing and jewelry should be removed and a patient gown or drape should be provided.
PATIENT POSITIONING
There is no need to tilt the bed for examination of the upper extremity. In fact, it is important to exam- ine the jugular and subclavian veins with the patient lying flat. This will remove any impact of hydrostatic pressure, which will tend to collapse the veins with the patient upright. While imaging the subclavian and jugular veins, the arm is positioned at the side with the head turned in the opposite direction. Imag- ing the rest of the arm veins can be done with the bed flat or with the head elevated. To view the axil- lary vein, the arm may be abducted to allow access to the axilla. The arm is then repositioned to a lower angle to allow access to the remaining arm veins.
EQUIPMENT
For the examination of upper extremity veins, at least two transducers are needed. As with the examination of the legs, a midrange transducer (5-10 MHz) will be commonly used to visualize the internal jugular, bra- chiocephalic, subclavian, axillary, deep brachial, and