Upper Extremity and Junctional Zone Injuries

Considerations for Management of Upper Extremity Vascular Trauma

• 1.

  Tourniquets for hemorrhage control, temporary shunts for early restoration of perfusion, and low threshold for fasciotomy when facing delayed repair or complex upper extremity injuries.

• 2.

  Prepare and drape the patient to allow for appropriate proximal and distal control of the injury, as well as harvesting of autologous conduit such as saphenous vein.

• 3.

  Exposure in the upper extremity junctional zone is difficult. Be prepared for sternotomy and thoracotomy.

• 4.

  Long bong fractures should be brought to length before vascular repair. (Consider immediate vascular shunt placement followed by placement of fixation devices.)

• 5.

  Liberal use of interposition grafting and patching avoids arterial narrowing that often results from primary repair.

• 6.

  Prosthetic conduit is an acceptable option in upper extremity junctional zone injuries where size match is important and where infectious complications are less common than in the groin.

• 7.

  Repair of venous injury may improve limb outcomes and should be entertained, particularly in the proximal upper extremity or junctional zone.

• 8.

  Endovascular repair of upper extremity vascular injury is now possible with reasonably good early results, particularly in proximal or central injuries.

• 9.

  Liberal use of Duplex ultrasound as a means to surveille the repair is recommended.

• 10.

  Elevation of the extremity, early rehabilitation, and antithrombotic therapy are important in the postoperative care after revascularization for upper extremity trauma.

Subclavian Artery Injuries

The relatively short extent of the subclavian vessels, along with their surrounding bony structures and musculature, makes injuries to these proximal upper extremity vessels rare. Although injury to the subclavian artery is more common in penetrating trauma, reports from military and civilian centers show the prevalence of subclavian artery injuries to range from 1% to 10%. Subclavian vascular injury should be considered when the bony structures of the thoracic outlet, such as the first rib or the clavicle are fractured. Subclavian artery injury may not present with critical ischemia given the ample collateral circulation around the shoulder. Absence of a distal pulse in an upper extremity, reduction in the injured extremity index (less than 0.9), or the presence of hemodynamic collapse with apparent mechanism should be considered highly suspicious for occult subclavian artery injury. In fact, many patients with a subclavian artery injury will present in shock. Hemopneumothorax is common. Other signs can include supraclavicular and low cervical swelling or tracheal compression from a hematoma. Concomitant injuries to the cervical or thoracic spine may be present, and brachial plexus injuries along with associated venous injury will commonly be present. Meticulous assessment for these injuries should be performed as soon as the patient's status permits.

Anatomy of the Junctional Zone and Subclavian Artery

The junctional zone of the upper extremity is composed of the thoracic aperture and shoulder. The articulations between the first rib, the sternum, and spinal column create the bony boundaries of the thoracic outlet. The clavicle connects to the manubrium anterior to the first rib, and these anatomic relationships make direct access to the vasculature, including the subclavian vessels and their branches, challenging. The musculature surrounding the thoracic outlet can be best visualized as an inverted cone with the anterior and posterior scalenes attaching to the first and second ribs, respectively, the sternothyroid; the sternohyoid attaching to the sternum; and the sternocleidomastoid attaching to the medial clavicle and sternum. Although the complexity of the anatomy in this area creates a protective cage for the underlying vessels and nerves, obtaining proximal control in rushed situations can easily result in inadvertent damage to critical structures.

The major arterial structure of the thoracic outlet is the subclavian artery ( Fig. 21.3 ). The right subclavian originates from the innominate artery posterior to the costoclavicular joint, and the left subclavian artery originates from the aortic arch at roughly the level of the 4th left interspace. The subclavian artery is divided into three sections based on the relationship to the anterior scalene and the branches provide collateral pathways around the shoulder ( Fig. 21.4 ). The first portion is proximal to the muscle and its branches include the vertebral artery, the thyrocervical trunk, and the internal thoracic artery. The phrenic and vagus nerves cross anterior to the artery, and the internal jugular and subclavian vein join anterior to the nerves. On the left, the thoracic duct courses across the proximal subclavian artery and drains into the junction of the left internal jugular and left subclavian vein. The mid portion of the subclavian artery is posterior to the anterior scalene, abuts the brachial plexus trunks located posteriorly and superiorly to the artery, and gives off the dorsalscapular branch. The third portion is located lateral to the anterior scalene and remains in close proximity to the brachial plexus as the cords form from the trunks. These cords are intimately associated with the third part of the subclavian artery, which does not have side branches.

Operative Management of Junctional Zone and Subclavian Artery

The proximal portion of the right subclavian artery can be exposed via a median sternotomy. Further exposure may require a supraclavicular extension of the incision, with or without resection of the clavicular head. The origin of the left subclavian artery is in a more posterior location on the aortic arch and must be exposed through a high, left anterolateral thoracotomy ( Fig. 21.5 ). The mid to distal left subclavian artery may be controllable through a median sternotomy with a supraclavicular or cervical extension or via “trapdoor” thoracotomy. When the goal is to expose the mid-portion of the artery, a combined supraclavicular and infraclavicular (two-incision) technique has been described, but in the authors' experience a single-incision approach with subperiosteal clavicular resection (with or without simultaneous reconstruction of the clavicle) seems most expeditious and flexible. A distal left subclavian and proximal axillary vessel injury can be exposed by a separate supraclavicular incision. Alternatively, the clavicle can be resected in a subperiosteal fashion to expose the subclavian vessels. The distal subclavian artery and proximal axillary artery is potentially treatable from a two-incision approach, but injury management may require a lateral clavicular resection, again with or without bony replacement.

Dissection in the area of the subclavian artery and vein should be performed with care given the abundance of adjacent nerve structures ( Fig. 21.6 ). In addition to the brachial plexus and vagus, the phrenic nerve sits on the anterior scalene muscle and should be identified and preserved. The abundance of collaterals around the shoulder and neck may allow for ligation of the subclavian artery in emergency situations with modest upper extremity ischemia. Temporary shunting, however, may be considered and, in the authors' opinions, provides a better alternative to ligation. Tension-free repair of the subclavian artery cannot be overemphasized as the vessel is relatively thin, nonmuscular, and delicate. Because of this, primary repair and patch angioplasty is challenging. If these are entertained, use of pledgets is recommended. Prosthetic material can be used as an interposition graft for larger, more proximal great vessel and upper extremity reconstructions. Autologous conduit such as saphenous vein, paneled saphenous vein, internal jugular vein, or even femoral vein can be used depending on size and length considerations. The choice is dependent on patient condition and associated soft-tissue injury. In more extensive injuries, ligation and revascularization using bypass with inflow based more proximally, such as from the ascending aorta, the innominate artery, or the carotid systems, may be options.

Operative Technique

In order to accomplish proximal surgical control of the left subclavian, an anterolateral thoracotomy is completed. Position the patient supine and place shoulder roll. Create a transverse, curvilinear incision over the left 5th rib from the lateral border of the sternum to the anterior axillary line (just below the breast in a female patient, along the lower contour of the pectoralis major muscle in a male patient). Divide the pectoralis fascia and muscle fibers at the 4th intercostal space, then the intercostal muscles. Enter the 4th intercostal space at the cranial aspect of the 5th rib and incise the parietal pleura. At this point, place a rib spreader retractor (i.e., Fianchetto rib retractor). Retract superiorly below the left lung caudally and visualize the aortic arch, then divide the mediastinal pleura overlying the arch and descending thoracic aorta. Identify the proximal origin of the left subclavian artery. Of note, avoid injury to the left vagus and recurrent laryngeal nerves at this location. Achieve proximal control of the left subclavian artery.

The supraclavicular approach to the subclavian provides exposure to the mid and distal portions of the artery. The surgeon should consider that this approach is more time-consuming and subjects critical nerve structures to risk. Position the patient supine and place shoulder roll. Create a transverse, supraclavicular incision approximately one fingerbreadth cranial to the clavicle with the medial extent originating at the medial aspect of the clavicular head of the sternocleidomastoid muscle. Divide the clavicular head of the sternocleidomastoid and expose the scalene fat pad. Identify and protect the phrenic nerve which is located at the anterior aspect of the anterior scalene muscle. Mobilize the scalene fat pad cephalolaterally. Complete a phrenic neurolysis to increase nerve mobility and facilitate division of the anterior scalene muscle. Divide (resect if required) the anterior scalene muscle and identify the underlying subclavian artery. Circumferentially, isolate the subclavian artery and achieve proximal and/or distal control. The thyrocervical trunk can be ligated if required.

The trapdoor thoracotomy provides excellent exposure to the left subclavian artery and is another option that surgeons should be familiar with. Perform an anterolateral thoracotomy as previously described. Next, control the proximal subclavian artery. Ligate the internal mammary/thoracic vessels and perform a supraclavicular approach as previously described. Then complete a vertical incision over the sternum to connect the medial borders of the anterolateral thoracotomy and supraclavicular incisions. Divide the exposed sternum via median sternotomy.