Chapter 45. Hilum and Great Vessel Wound Management

Injuries to the thoracic great vessels can be a significant cause of morbidity and mortality. Large vessels in the hilum of the lung include the pulmonary artery and vein. The great vessels also include the vena cava, aorta, innominate artery, subclavian artery, and subclavian vein. The mortality from injuries to the subclavian artery is approximately 5% if patients who are moribund on admission to the Emergency Department are excluded.1 However, the mortality from injury to the vena cava and the pulmonary vessels is over 60%.2 While over 85% of patients with penetrating injuries to the thorax are stable, the remainder present in varying levels of hypovolemic shock. They may have bled externally or into the chest. Each hemithorax can hold up to one-half of an individual's blood volume. In these cases, an Emergency Department thoracotomy may be performed for hypovolemic shock.

Injury to the thoracic great vessels may be due to blunt trauma, diagnostic procedures, iatrogenic causes, or penetrating trauma. Crush injuries, deceleration injuries, motor vehicle versus pedestrian collisions, and penetrating thoracic injuries may all signify an injury to a thoracic great vessel. The vessels that are most commonly injured include the aorta, innominate artery, pulmonary vein, and venae cavae.

The portable anteroposterior chest radiograph is the initial radiographic screening. It may reveal loss of the aortic knob contour, left-sided pleural effusions, mediastinal widening, nasogastric tube deviation, or tracheal deviation, all of which suggest injury to a great vessel. Other findings suggestive of such an injury include depression of the left mainstem bronchus, left apical capping, narrowing of the carinal angle, sternal fractures, opacification of the aortopulmonary window, and widening of the paraspinous stripe.

Numerous physical examination findings are suggestive of a thoracic great vessel injury. Asymmetric pulses or unequal blood pressures between the extremities are quick and simple to evaluate. Hypotension may be due to internal or external hemorrhage. Steering wheel contusions, sternal fractures, thoracic spine fractures, and a left-sided flail chest signify potential intrathoracic injury. A thoracic outlet hematoma or a hoarse voice can occur from injury to the aorta or one of its major branches. Paraplegia may be due to hypotension or an aortic disruption.

Attempts should be made to control any laceration or rupture of the thoracic great vessels.

There are no absolute contraindications to temporarily controlling any hemorrhage from a thoracic great vessel after performing a thoracotomy (Chapter 42). The thoracotomy should not be performed if the patient has obvious signs of death, no vital signs in the field, or no vital signs for over 15 minutes. A pericardial tamponade or cardiac injury may require management prior to managing a great vessel injury.

• 3-0 Prolene suture
• Foley catheters, sizes 14 to 20 French
• 10 in. needle driver
• Satinsky, or other, atraumatic vascular clamp (Figure 45-1)
• Sterile saline
• 20 mL syringe
• Laparotomy pads
• Gauze 4 × 4 squares
• Umbilical clamp
• Hemostats

There is no preparation required other than performing an anterolateral thoracotomy (Chapter 42). The patient should be intubated, ventilated with 100% oxygen, and fully monitored (i.e., telemetry, a noninvasive blood pressure cuff, and pulse oximetry). Instruct a nurse to administer intravenous broad-spectrum antibiotics that cover skin flora, gram-positive organisms, and gram-negative organisms. The Emergency Physician should wear full personal protective equipment to protect themselves from contact with the patient's blood and body fluids. While time is of the essence and this is an emergent procedure, aseptic technique should be followed.

Digital Occlusion

Digital pressure may be used to control small lacerations of the thoracic vena cava. It will provide adequate hemostasis while repairing the wound. Place a fingertip over the defect. Do not place a finger in the defect. Place horizontal mattress sutures using 3-0 Prolene to close the defect. Unfortunately, the fingertip interferes with visualization of the wound and places the Emergency Physician at risk for a needlestick injury. The fingertip will have to be intermittently removed to place the sutures.

Digital pressure and rapid transport to the operating room is the most practical method of dealing with injuries to the subclavian vessels. These vessels are extremely difficult to control through a traditional anterolateral thoracotomy incision. If digital pressure is ineffective, pack the apex of the thoracic cavity with laparotomy pads or gauze squares and apply compression from below.

Foley Catheter Technique

By inserting a Foley catheter into the vessel, inflating the cuff, and placing it under gentle traction, one may occlude a wound to a great vessel (Figure 45-2). As with digital occlusion, this is only a temporizing measure. Inflate the cuff of the Foley catheter with sterile saline to check its integrity and look for leaks. Deflate the cuff. Place a hemostat on the Foley catheter proximal to the cuff. This will prevent air from being drawn through the catheter and causing an air embolism.

Identify the location of the vascular injury. Insert the catheter through the wound until the cuff is within the vessel (Figure 45-2A). Open the hemostat, inflate the cuff with 5 to 10 mL of sterile saline, and reclamp the Foley catheter. This step should be completed quickly to prevent air from being drawn through the catheter. Do not overinflate the cuff so that it occludes flow through the vessel. Apply gentle traction to the catheter (Figure 45-2B). Apply just enough traction to mostly occlude the wound and slow the bleeding. Do not try to provide complete hemostasis. This will result in excessive traction on the catheter, causing the cuff to pull through the wound, enlarge the wound, and further injure the vessel. Place an umbilical clamp or a hemostat on the catheter just outside the vessel to prevent it from migrating into the vessel (Figure 45-2C).

The Foley catheter technique is simple and effective. It avoids the problems associated with digital occlusion. It does not interfere with visualization of the wound or the simultaneous performance of cardiac massage. Intravenous catheter tubing may be inserted into the lumen of the Foley catheter to infuse crystalloid solutions or red blood cells directly into the heart and central circulation.

Cross-Clamping Technique

Injuries to the thoracic great vessels can bleed profusely and are difficult to control. Digital occlusion is often ineffective. An atraumatic Satinsky vascular clamp can be placed to partially occlude the great vessel and isolate the injury (Figure 45-3). This will provide temporary hemostasis until definitive repair in the Operating Room.

Large wounds and complete transections are difficult to manage. Injuries to the pulmonary vasculature in the region of the hilum are most expeditiously controlled by placing an atraumatic vascular clamp across the respective hilum.3 Grasp the hilum between the thumb and the forefinger. Place the clamp carefully around the entire hilum. Take care not to injure the pulmonary parenchyma or the vessels any further. Vascular injuries may be controlled by placing a cross-clamp proximal to the injury and occluding the backbleeding with additional clamps (Figure 45-4). These patients should be immediately transported to the Operating Room to be placed on bypass and repair the injuries. It is not recommended for the Emergency Physician to suture great vessel injuries in an attempt to repair them.

If the patient is resuscitated, cover the thoracotomy wound with saline-moistened gauze and a simple dressing. Administer broad-spectrum antibiotics if not done previously. Immediately transport the patient to the Operating Room for definitive repair of the great vessel injury and any other injuries by a Trauma or Cardiovascular Surgeon.

The complications associated with digital pressure include extending the injury if the procedure is not performed carefully. Inaccurate digital control can lead to unnecessary loss of blood during transport of the patient to the operating room. Foley catheters, if pulled too tightly, can become dislodged and restart troublesome bleeding. They can also enlarge a wound if the cuff pulls through the wound. The cuff may obstruct flow through the vessel and compromise cardiac output. Decrease the cuff size by withdrawing some of the saline from the cuff. An overly rough mobilization and clamping can increase the size of the injury and cause massive bleeding. Cross-clamping of the aorta and/or pulmonary artery will obstruct peripheral blood flow. The vessel must be repaired or the patient placed on bypass to prevent anoxia and permanent neurologic dysfunction.

Injuries to the thoracic great vessels carry a high mortality as bleeding occurs unimpeded into the pleural space. The survival of the patient depends on their presenting condition as well as the speed and accuracy with which the intrathoracic hemorrhage is controlled.