Vascular Occlusive Syndromes of the Upper Extremity Treatment & Management

Chronic vascular occlusive diseases

Chronic vascular occlusive diseases occur secondary to repetitive trauma; atherosclerosis; proximal embolic events; systemic diseases, such as collagen vascular disease and vasculitis; and/or hypercoagulable states. Symptoms include pain, pallor, cold intolerance, paresthesias, and ulcerations. Such symptoms may present suddenly in workers who perform repetitive maneuvers involving a hammerlike device. Referred to as hypothenar hammer syndrome, this syndrome presents with pain in the region of the hook of hamate along with paresthesia and decreased temperatures in the ring and little fingers. This syndrome is caused by disruption of the internal elastic lamina, resulting in aneurysmal dilatation and mural thrombosis of the ulnar artery in the Guyon canal. Diagnosis is made based on history and pulsatile mass present in 10% of patients or on findings from Doppler ultrasound or angiography of the upper extremity.

Treatment for chronic vascular occlusive diseases involves thrombolytic agents acutely and, if these are unsuccessful, surgery. Because of the pathophysiology of thrombus formation and maturation, it is important to note that thrombolytic agents are not typically successful. In hypothenar hammer syndrome, surgical intervention includes resection of the ulnar artery locally, since the thrombosed vessel causes focal inflammation and swelling and sympathetic hyperstimulation of the adjacent ulnar nerve segment. Ulnar artery bypass graft with a vein conduit is recommended if patients complain of persistent pain and cold intolerance of the involved digits and if the segmental digital-brachial pressure ratio is less than 0.7. Otherwise, segmental resection is appropriate if the collateral circulation is sufficient. Despite these guidelines, adequacy of vascular flow distally into the digits cannot be confirmed until the vascular segment has been resected intraoperatively.

Thoracic outlet syndrome

Thoracic outlet syndrome follows compression of the subclavian artery and lower brachial trunk of the brachial plexus. Patients typically present with reports of ulnar dermatome paresthesia, especially of the small finger. Systemic symptoms may include occipital headaches. Diagnosis can be made based on a positive result on an Adson test, a costoclavicular maneuver, a Wright hyperabduction external rotation test, or a Russe overhead exercise test. Chest radiography with lordotic views may demonstrate an accessory cervical rib, which can be the source of compression on neurovascular bundles. Finally, diagnostic infiltration of local anesthetic solution into the anterior scalene muscle (diagnostic anterior scalene block) can be used to diagnose thoracic outlet syndrome.

Treatment of thoracic outlet syndrome involves physical therapy to allow for muscle rebalancing, scalene muscle lengthening, and improved brachial plexus gliding. Physical therapy may also result in postural correction and strengthening of shoulder girdle muscles. If physical therapy is not successful, then anterior scalenotomy, brachial plexus neurolysis, and first-rib resection have been described with variable efficacy.^[6]

Embolism

Embolism to distal vessels results in acute pain and pallor in previously noncompromised tissue. Patients present with the classic bluish finger and demonstrate petechiae of the digital tip and nail beds. As many as 70% of upper extremity emboli arise from the heart, but the subclavian artery (as part of thoracic outlet syndrome) and superficial palmar arch also are common sources. Cardiac sources produce mural thrombi that develop in the setting of atrial fibrillation; subclavian arterial thrombi are caused by compression from thoracic outlet syndrome.

Embolism treatment consists of immediate anticoagulation with heparin followed by 3 months of warfarin therapy. Thrombolytic therapy has been advocated as being more efficacious. Local treatment of acute small-vessel occlusion through infusion via a catheter floated down the radial or ulnar artery is often preferable for reasons of efficiency. This also reduces the risk of systemic complications, particularly in the case of tissue plasminogen activator (t-PA), which has the additional advantage of an extremely short half-life. Embolectomy can be attempted if emboli are embedded in vessels proximal to the superficial arch.

Aneurysm

An aneurysm may form in the vessel wall following intraluminal injury that leads to uniform and gradual dilatation of the vessel wall. This is in contrast to a pseudoaneurysm, which develops following penetrating injury of the vessel wall, leading to a saclike out-patching without an endothelial lining. Aneurysms present as expanding, palpable, painless masses. Symptoms may develop only following external compression of neighboring sensory nerves. The natural course of these lesions involves slow progression to thrombus formation and production of emboli. Diagnosis can be confirmed based on Doppler ultrasonography, angiography, or both. Treatment involves resection of the lesion and repair with a patch graft or interposition graft.

Raynaud disease and Raynaud phenomenon

Raynaud disease is a purely vasospastic condition without underlying cause, sometimes leading to acral necrosis. It is defined in Dorland's Illustrated Medical Dictionary as "a primary or idiopathic vascular disorder characterized by bilateral attacks of Raynaud phenomenon." Raynaud disease usually occurs in persons aged 30-50 years. Prevalence is greater in females than in males, and symptoms last more than 2 years. Patients demonstrate bilateral hand involvement, with pallor of digits secondary to cold exposure or psychologic stressors. Patients report dysesthesia of involved digits. Diagnosis of Raynaud disease is made on the basis of demonstration of triphasic color change of the overlying digit skin.

In contrast to Raynaud disease, Raynaud phenomenon presents concurrently with CREST syndrome (see CREST Syndrome), in which tissue necrosis results from spastic and occlusive disease. CREST syndrome refers to disease processes involving symptoms of generalized calcinosis, Raynaud phenomenon, esophageal dysfunction, scleroderma, and telangiectasia. Symptoms specific to Raynaud phenomenon include digital ischemic pain, nonhealing ulcers, and development of gangrene. Moreover, patients present with progressive joint contractures, including adduction contracture of the thumb and fixed flexion contractures of proximal interphalangeal joints with secondary extension contracture of the metacarpophalangeal joints. Ulcers develop over the proximal interphalangeal joints secondary to ischemia, pressure, minor trauma, or a combination of factors.^[7]

Initial treatment of both Raynaud disease and Raynaud phenomenon involves inhibition of vasospasms, thus improving microvascular flow and maximizing capillary perfusion. Treatment initially consists of cessation of smoking, biofeedback therapies (temperature control), and calcium channel blockers.^[8] Avoiding exposure to cold by wearing protective garments, including hand warmers, are important first-line measures. Raynaud disease is most effectively treated with these conservative measures.

Raynaud phenomenon, unlike Raynaud disease, is an intermittent bilateral attack of ischemia of the fingers or toes, as well as sometimes of the ears or nose. It is marked by severe pallor and is often accompanied by paresthesia and pain. The condition is brought on by cold or emotional stimuli, and the symptoms are relieved by heat. Raynaud phenomenon may be idiopathic, often afflicting young females of slender stature, or it may be secondary to an underlying, identifiable disease, such as scleroderma. The diagnostic term Raynaud phenomenon refers solely to the signs and symptoms consistent with the vasospastic episodes. Raynaud phenomenon does not lead to ischemic ulcers, whereas the underlying condition may lead to ulceration.

Management eventually requires surgical intervention with peripheral/periarterial sympathectomy. This includes dissection of adventitia from arterial trunks and transection of neural connections between involved arteries and paired peripheral nerves. Other surgical modalities include vascular bypass and/or cervicothoracic sympathectomy, each of which results in a 50% recurrence of symptoms. Treatment for contractures is dependent on disease severity. If contractures are mild, physical therapy is employed; if contractures are severe or dorsal skin ulcers are present, arthrodesis of proximal interphalangeal joints into a functional position is performed, which promotes primary wound closure. Maintenance of the digital cascade is pursued.

Advanced peripheral vasculitis conditions

Advanced peripheral vasculitis conditions include Wegener granulomatosis, Churg-Strauss syndrome, Takayasu arteritis, Buerger disease, and giant cell arteritis. Takayasu arteritis is referred to as the pulseless disease. It occurs in females aged 10-30 years and involves stenosis of the aortic arch, carotid arteries, and, less often, upper extremity vessels. Giant cell arteritis involves the subclavian vessels and affects women older than 50 years. It is associated with increased erythrocyte sedimentation rate values. Treatment involves systemic steroids. Buerger disease, referred to as a thromboangiitis obliterans, involves vasculitis of medium-size and small vessels. It is associated with smoking and affects the lower extremities more than it does the upper extremities. Treatment is focused on behavior modification, such as avoidance of coldexposure and cessation of smoking.

Anticoagulation and thrombolysis are rarely effective in these disease processes. Therefore, vascular reconstruction with venous or arterial grafting is generally necessary for definitive treatment. Bypass grafting following complete occlusion of involved vessels is inevitable because anticoagulation and thrombolytic therapy have not proven to be efficacious.

When one considers digital-vessel bypass surgery, considering digital-vessel diameters is important. In general, the proper digital vessels are smaller than the common digital vessels. Additionally, the diameters of the ulnar proper digital vessels of the thumb, as well as of the index and long fingers, are greater than those of their corresponding radial proper digital vessels. In contrast, the radial proper digital vessels of the ring and small fingers are larger than their corresponding ulnar proper digital vessels. Preoperative arteriography may demonstrate an incomplete arch or thrombosis of the radial or ulnar arteries, especially in women smokers.

Traumatic, acute arterial injury is common and may occur after penetrating or blunt trauma. Most isolated vascular injuries do not require immediate attention, since collateral perfusion prevents tissue compromise. Critical injuries following penetrating trauma that require immediate revascularization typically occur if the brachial artery or both the radial and ulnar arteries have been severed. Infrequently, vascular repair of a single ulnar or radial injury is necessary because of inadequate collateral flow from the remaining intact artery. Brachial injuries occurring proximal to the origin of the profunda brachii are most susceptible to distal tissue perfusion compromise.

Critical injuries following blunt trauma involve either a closed brachial artery laceration due to a supracondylar humerus fracture or development of compartment syndrome after a crushing or penetrating injury that causes arterial injury. If treated promptly with immediate wide fasciotomy, increased pressures leading to tissue death and functional deficit may be avoided. If left untreated, the patient develops an intrinsic plus position hand deformity associated with intrinsic muscle contraction. Signs of intrinsic contracture include metacarpophalangeal joint flexion and interphalangeal joint extension; passive hyperextension of the metacarpophalangeal joint decreases active and passive flexion capacity of the interphalangeal joints. The Bunnell intrinsic tightness test confirms only contracture of intrinsic muscles. This syndrome results in increased intracompartmental pressures, typically greater than 30 mm Hg, which result in necrosis of the deepest muscles.

If hypoperfusion is suspected, the DBI may be obtained to assess perfusion following arterial injury, and a Striker needle can be used to monitor intracompartmental pressures following crush injuries. Digital pulse oximetry is helpful as well. In all suspected vascular injuries that are treated conservatively, close monitoring is necessary. For example, following high-energy gunshot wounds with arterial contusion, thrombosis and progressive ischemia are not uncommon after prolonged delays. In contrast, some clinical suspicion of a forearm compartment syndrome is a sufficient indication for fasciotomy, particularly because pressure measurements and other laboratory tests may be unreliable and user dependent and will inevitably delay definitive treatment.

Traumatic, noncritical vascular injuries involve cases in which tissue perfusion is not compromised, despite vascular injury. Although not absolutely indicated, revascularization can be undertaken in some of these situations. The clinician may choose to repair vascular injuries intraoperatively if exploration of the injury must be undertaken to repair the injury and to rule out injury to other vital structures, such as tendons and nerves. Arterial repair may restore enhanced parallel flow in case of future injury, prophylaxis against future cold intolerance symptoms, and enhanced tissue healing. Thrombosis rate following radial or ulnar artery repair at the wrist is high and may negate this endeavor.

Iatrogenic arterial injuries involve procedures requiring arterial cannulation or injection. Brachial artery injury is observed in approximately 0.5% of patients following cannulation for cardiac catheterization. Similarly, injury to the radial artery is observed in 23% of patients following repeated measurement of arterial blood gasses. Such injuries may result in pseudoaneurysm formation, creation of an arteriovenous fistula, or acute thrombosis with distal embolization.

The most routine diagnostic test involves use of handheld Doppler imaging to evaluate pulses distal to the gross injury while compressing any sources of collateral flow. Alternatively, color duplex Doppler ultrasonography can be used to evaluate vessel structural integrity. Although arteriography is the criterion standard test for vascular integrity, its use is not routine.

Surgical reconstruction must be undertaken under tourniquet control in the operating room and with the aid of loupe or microscopic magnification. Surgical exposure is necessary and is provided for by extension of the traumatic laceration both proximally and distally. Following debridement of necrotic tissue, vital structures must be identified and tagged both proximally and distally prior to any repairs. In particular, vessels are trimmed to healthy intimal tissue and clamped with atraumatic vascular clamps.

Vessel repair must be performed without tension, thus necessitating use of reversed interposition vein grafting if the vessel stumps cannot be juxtaposed following mobilization. Vessel mobilization can be optimized by ligation of nonessential branches. Donor-site venous grafts depend on the caliber of the injured vessel and can include superficial veins of the dorsum of the hand; superficial veins of the arm, such as the cephalic and basilic veins or their terminal branches; or harvests taken from the lower leg, such as the distal saphenous vein or its terminal branches.

Following surgical repair and before release of vascular clamps, systemic heparin (3000-5000 U) is administered. Postoperatively, only aspirin (325 mg/d PO) administration is recommended unless intraoperative anastomosis complications are confronted, in which case postoperative heparin infusion is continued.

Various other surgical interventions have been described for management of vascular injuries. In the setting of bony injuries or more critical injuries that require immediate attention, prolonged extremity ischemia can be avoided with temporary silastic catheter shunting. Fasciotomy is indicated in the setting of overt or impending compartment syndrome. Although not regularly required, venous repair is indicated in the setting of circumferential soft-tissue injuries or amputation injuries with compromise of all venous outflow. Adequate venous drainage of the upper extremity requires a minimum of 1 draining vein (although 2 veins are preferred) and can be provided with reconstruction of a combination of the following: cephalic vein, basilic vein, and vena comitantes.

Venous insufficiency can be detected following appropriate arterial inflow and presents with gradual distention and a bluish appearance of the distal extremity. Following iatrogenic injuries, acute thrombolytic therapy has been advocated as first-line therapy, especially for cases involving embolic showering to distal nutrient microvessels. However, thrombolytic therapy is contraindicated in the presence of pseudoaneurysm. For cases of thrombosis and emboli to large vessels, embolectomy using arteriotomy with a Fogarty balloon catheter has been advocated. Finally, suture ligation of arteriovenous fistulas and patch graft using venous tissue for pseudoaneurysm or intimal flap repair may be required.