Once an airway has been established using the emergency techniques previously described or with standard endotracheal intubation, a rolled sheet is placed transversely under the shoulders to hyperextend the neck. The patient is then placed in a sitting position to bring the operative field closer to the surgical team.
With a unilateral track of penetrating wound or with any aerodigestive injury below the larynx in Zone II, an ipsilateral oblique incision is made along the anterior border of the sternocleidomastoid muscle. The length depends on the location of the known or presumed injury, the likelihood of a significant vascular injury, and the experience of the surgeon. For example, a patient with a large unilateral hematoma in Zone II overlying a presumed injury to the carotid artery or internal jugular vein should have an incision extending from the sternum inferiorly to the mastoid process superiorly. Such an extensive incision will allow for proximal and distal vascular control around the injury before entering the hematoma. In contrast, a patient without symptoms and signs of a vascular injury despite a deep stab wound in Zone II may be explored through a more limited oblique incision by an experienced surgeon.
When the track of a missile is through Zone II bilaterally, a high anterior collar incision at the level of the track of the missile is appropriate. Depending on the patient’s hemodynamic status, superior and inferior subplatysma flaps are raised, the midline raphe of the sternohyoid muscles is opened longitudinally, and the sternohyoid muscles are separated from the sternocleidomastoid muscles laterally. An injury on either side of the neck that is higher than expected can be exposed through an oblique extension of one side of the collar incision.
The appropriate incision for probable or documented injury in Zone I will depend on the likely injury, the patient’s hemodynamic status, and the experience of the surgeon. A profoundly hypotensive patient with active intrapleural hemorrhage from an injury to a great vessel in the superior mediastinum or a subclavian vessel behind the clavicle should have an ipsilateral high (above the nipple) anterolateral thoracotomy. If the injury is on the right side, a trans-sternal extension and left anterolateral thoracotomy (above or below the nipple) is added to allow for cross-clamping of the descending thoracic aorta as part of resuscitation. Vascular control is then obtained with pack compression or direct clamping. When the patient is modestly hypotensive (systolic blood pressure 90–120 mm Hg) and there is a hematoma in the superior mediastinum, a median sternotomy with a cervical or supraclavicular extension is appropriate. In the stable patient with a localized vascular injury on a CTA or conventional arteriogram, a median sternotomy or supraclavicular incision is chosen depending on which vessel is injured.
In the rare patient with hemorrhage from a penetrating wound to the internal carotid artery at the base of the skull in Zone III, a balloon catheter is passed through the entrance site as previously noted. Inadequate vascular control with the balloon inflated should prompt an ipsilateral oblique cervical incision to allow for exposure of the internal carotid artery and transarterial passage of a Fogarty balloon catheter for internal tamponade.115
Injury to the Carotid Artery
Patients with “hard” signs of an arterial injury such as external hemorrhage from Zone II, internal hemorrhage into the trachea or esophagus, or the presence of a pulsating/expanding hematoma in the anterior triangle of the neck should undergo immediate cervical exploration. In patients with loss of the carotid pulse, but no neurological deficit, many centers choose to perform a CTA to verify thrombosis of the internal carotid artery. Management of a documented thrombosis from a penetrating wound in the asymptomatic patient (observation vs revascularization) is controversial. The presence of a suspected carotid artery–internal jugular vein fistula, particularly in high Zone II or in Zone III, should prompt a CTA, as well. Depending on local expertise, a documented arteriovenous fistula may be treated with an endovascular stent or an open repair.
As previously noted, patients with “soft” signs of an arterial injury still undergo a diagnostic workup in many centers. Included would be patients with a history of bleeding at the scene or in transit, a gunshot wound passing through Zone II, a stable hematoma, or a neurological deficit such as hoarseness from an injury to the vagus nerve proximal to the origin of the recurrent laryngeal nerve. Management will vary depending on the magnitude of any injury to the carotid artery documented on a CTA, conventional arteriogram, duplex ultrasonography, or color flow Doppler examination. In general, extravasation, the presence of an early, pulsatile pseudoaneurysm, significant disruption of the intima, or significant disruption of flow to the brain mandates ipsilateral cervical exploration and repair of the common or internal carotid artery.
Patient with an Associated Neurological Deficit
A neurological deficit in a patient with a penetrating wound to the common or internal carotid artery may be due to cerebral ischemia from the injury itself, hypotension from hemorrhage, acute alcoholic intoxication, or the use of illicit drugs. In patients with any neurological deficit short of coma (GCS < 8), immediate repair of the carotid artery is indicated as the etiology of the deficit is unknown.115,116,117,118,119,120,121 The often-quoted review article by Liekweg and Greenfield in 1978 documented that a “favorable outcome” occurred in only 27% of patients undergoing carotid revascularization versus 25% undergoing ligation when “coma” was the presentation.122
In the case where a patient is found to have a carotid thrombosis with a neurological deficit, and a significant (several hours) delay in diagnosis, repair should not be attempted due to the significant possibility of hemorrhagic stroke.
Exposure of Injuries in Zone III
When stenting is not appropriate for an injury to the internal carotid artery in Zone III (ie, active hemorrhage, pseudoaneurysm has failed stenting with trans-stent coil, the internal carotid artery is very small), an operative approach is indicated. Exposure of the distal internal carotid artery at the base of the skull is obtained by a “stepladder” mandibulotomy,123 subluxation of the temporomandibular joint with interdental wiring124,125,126 or with monocortical screws and steel wiring,127 or a vertical ramus osteotomy.128
In the absence of other significant injuries, systematic heparinization (100 U/kg) is used when any repair more complex than lateral arteriorrhaphy is needed (Table 22-2). Repairs of the carotid artery are accomplished using standard techniques including the following: (1) minimal debridement and lateral arteriorrhaphy with interrupted 6-0 polypropylene sutures for a lateral defect; (2) patch angioplasty with saphenous vein, thin-walled polytetrafluoroethylene, or bovine pericardium for loss of one wall; (3) segmental resection and end-to-end anastomosis for through-and-through injuries or segmental disruption; and (4) segmental resection and insertion of a saphenous vein or polytetrafluoroethylene interposition graft.12,117,119 On rare occasions, an injury to the proximal internal carotid artery may be repaired by ligating and dividing the distal external carotid artery and using the proximal segment as a transposition graft.
TABLE 22-2Principles of Repair of the Carotid Artery ||Download (.pdf) TABLE 22-2 Principles of Repair of the Carotid Artery
Systemic heparinization (100 U/kg) if complex repair (resection with end-to-end anastomosis or interposition graft) or repair at base of skull will be necessary
No intraluminal shunt unless inadequate back-bleeding or prolonged repair at base of skull will be necessary
Interrupted 6-0 polypropylene suture repair in children or in internal carotid artery in all patients
Flushing sequence after verifying back-bleeding is externally, and then into external carotid artery, and, finally, flow is reestablished into internal carotid artery
In a young patient with excellent back-bleeding from the internal carotid or common carotid artery after distal vascular control has been attained, an intraluminal shunt is not indicated as the repair is completed. With a rare distal injury in the internal carotid artery in upper Zone II or in Zone III, insertion of a graft may take longer than 30 minutes. In this situation, a temporary intraluminal shunt should be considered as the repair is completed.
As cross-clamping of the common or internal carotid artery after a period of hypotension and during a period of repair may result in ipsilateral cerebral ischemia, postoperative care is critical.129 The possibility of an ischemia–reperfusion injury with secondary ipsilateral cerebral edema mandates avoiding hypotension and hypoxemia as well as performing serial careful postoperative neurological examinations.
Should the patient have no improvement of preoperative neurological symptoms or develops neurological deterioration in the early postoperative period, emergent CT of the brain is performed. Ipsilateral cerebral edema is treated with the insertion of an intracranial pressure monitor as well as standard drainage and medications such as hypertonic saline and/or mannitol.
In one older series, the survival rate for all 129 patients undergoing operation on an injured carotid artery was 75%.117 When patients failing resuscitation were excluded, the survival rate was 85%.117
Injury to the Vertebral Artery
An injury to the vertebral artery such as dissection from blunt trauma or intimal disruption, a pseudoaneurysm, arteriovenous fistula, or active hemorrhage from a penetrating wound is usually diagnosed on a CTA or other imaging study in the hemodynamically stable patient. Appropriate treatment is the placement of an endovascular stent for a pseudoaneurysm or intimal lesion and acute balloon occlusion, if needed, followed by coil embolization of an arteriovenous fistula or active hemorrhage.130,131
In patients undergoing a cervical exploration for hemorrhage or a suspected injury to the aerodigestive systems, active hemorrhage originating from the posterolateral neck adjacent to the spinal transverse processes is likely from an injured vertebral artery. While detailed descriptions of operative approaches to the different levels of the vertebral artery are available, they are almost never utilized in the modern era.132,133,134 As proximal ligation of the ipsilateral vertebral artery originating from the second portion of the subclavian artery is unlikely to stop the hemorrhage, packing with bone wax or gauze is commonly utilized and is nearly always successful. Many surgeons leave the bone wax in place, while the gauze pack will need to be removed at a reoperation. After packing, an ipsilateral vertebral CTA followed by proximal embolization is appropriate.
With occlusion of the vertebral artery by the trauma itself or by operative ligation or coil embolization, antegrade thrombosis is a risk in the postoperative/postprocedure period. For this reason, anticoagulation with heparin is appropriate before discharge. Whether long-term anticoagulation is necessary is still unclear at this time.
When unilateral vertebral artery ligation, packing, or coil occlusion is performed, a mortality of 5–15% expected.132,135 Deaths are invariably due to prehospital exsanguination or an associated injury to the brain.
Injury to the Internal Jugular Vein
Lateral venorrhaphy is appropriate for wall defects, while more extensive injuries are treated with ligation. As bilateral ligation of the internal jugular veins may result in pseudotumor cerebri, every effort should be made to repair one internal jugular vein when bilateral injuries are present.
The simplest technique to expose the cervical esophagus is to dissect down to the cervical vertebral bodies and then lift the posterior wall of the esophagus off them by stripping with a finger (Table 22-3). Exposure of the anterior esophagus requires some care, as the recurrent laryngeal nerves are located in the tracheoesophageal groove at the lower cervical level. Once the esophagus has been dissected circumferentially, it can be looped with a finger or Penrose drain and carefully inspected by pulling it toward the operating surgeon. Any area of hematoma staining should be gently explored with a scissor to see if the mucosa underneath has been perforated. If the mucosa is intact, the esophageal muscle is reapproximated with several simple interrupted sutures of 3-0 absorbable material.
TABLE 22-3Principles of Repair of the Esophagus ||Download (.pdf) TABLE 22-3 Principles of Repair of the Esophagus
Either one- or two-layer repair with absorbable sutures is acceptable, preferably in a transverse direction
Loss of portion of the wall in Zone II and some patients with a delayed diagnosis of perforation should be treated with a loop esophagostomy over a rod rather than an acute tenuous repair that is likely to dehisce
Combined injuries with the trachea or carotid artery mandate a vascularized muscle buttress/separator such as the sternocleidomastoid muscle
On occasion, it may be necessary to have the anesthesiologist help make the diagnosis of a small occult perforation in the cervical esophagus. One technique is to compress the distal esophagus at the thoracic inlet and to fill the proximal esophagus with 30–50 mL of methylene blue dye in saline (one ampule in 200 mL). Full-thickness staining of dye at any location suggests that a perforation is present. Another technique is to place the tip of a nasogastric tube in the midcervical esophagus, compress the distal esophagus with a finger or noncrushing clamp, and have the anesthesiologist inject 30–50 mL of air into the proximal esophagus through the nasogastric tube. By filling the operative field with saline solution, any air leak from an occult perforation would be seen as bubbling into the saline.
With a limited injury from a stab or gunshot wound, minimal debridement is performed. A two-layer repair starts with a continuous 3-0 absorbable suture closure of the mucosa, preferably in a transverse direction. The repair is completed by placing interrupted 3-0 absorbable sutures through the muscularis layer of the esophagus. As there is a 5–25% leak from repairs of the cervical esophagus historically, a small Penrose drain or closed suction drain is placed adjacent to the repair before closure of the incision.136,137,138,139 This drain is brought anteriorly so as not to cause erosion of the carotid artery laterally.
When there has been a loss of tissue from one wall or the diagnosis of a perforated cervical esophagus has been delayed, a simple lateral suture repair or end-to-end anastomosis is not appropriate. A lateral blowhole esophagostomy at the site of the defect is placed over a red Robinson catheter (much like a rod under a loop colostomy) located in the incision or lateral to it.140,141 Whether a tie of absorbable suture material should be placed around the distal side of the elevated loop remains controversial.141 Keeping the esophagus in continuity, even with a large defect, will preserve esophageal length and avoid the need for a colon interposition or free jejunal graft in the future. Conversion to a loop esophagostomy rather than performing a tenuous repair avoids the complication of a large esophagocutaneous fistula with secondary problems such as tracheoesophageal fistula, carotid artery blowout, or wound infection in the postoperative period. The esophagostomy has a tendency to shrink and to pull to the posterior midline over time, and delayed closure is often much easier than expected (Fig. 22-8).
Closure of loop cervical esophagostomy was a relatively easy procedure in this patient who had esophagogastrectomy after a distal esophageal repair leaked.
Anterior or lateral perforations are not debrided and are closed with interrupted full-thickness 3-0 absorbable sutures to create an airtight seal (Table 22-4).67,142 When there is tissue loss in the anterior or lateral trachea, a tracheostomy tube can be placed into the defect until a decision is reached on use of a vascularized muscle patch or formal reconstruction. Should the large defect be in the proximal trachea, the sternal head of the sternocleidomastoid muscle is detached, rotated medially, and sewn directly to the defect to create an airtight seal after removal of the tracheostomy tube. Resection of a large defect, mobilization of both ends of the trachea, and an end-to-end anastomosis have never been performed at a first operation in the senior author’s experience.
TABLE 22-4Principles of Repair of the Trachea ||Download (.pdf) TABLE 22-4 Principles of Repair of the Trachea
No debridement is necessary
One-layer repair with absorbable suture if small or moderate-sized hole
When there is loss of a portion of the anterior or lateral wall, a tracheostomy tube is inserted into the defect. The sternocleidomastoid muscle is then detached inferiorly, mobilized, and sewn in an airtight fashion to the defect after the tracheostomy tube is removed
When there is loss of a portion of the membranous trachea, a three-sided rectangular longitudinal flap of pericardium based superiorly is sewn to the defect to create an airtight seal
When there is a large defect in the membranous portion of the cervical trachea, a three-sided longitudinal anterior pericardial flap based superiorly is created after a median sternotomy is performed. The pericardial flap is then sewn to the defect in the membranous trachea to create an airtight seal.
Late reconstruction of a previously injured trachea with a segmental partial loss of tissue is best performed by a thoracic surgeon with experience in tracheal resection and reconstruction. Dissection should be limited at the 3 and 9 o’clock areas of the trachea to avoid devascularizing the ends. Both laryngeal lowering and bilateral lung elevating procedures may be necessary with gaps in the trachea exceeding 5–6 cm.143 Repair is accomplished with interrupted 3-0 absorbable sutures, no protective tracheostomy is performed, and a sternocleidomastoid muscle flap may be used to buttress the suture line (see following discussion).
Combined Injuries to the Trachea–Esophagus, Trachea–Carotid Artery, or Esophagus–Carotid Artery
A postoperative complication rate of 74% was reported in one older series of 23 combined tracheoesophageal injuries.144 Analysis of the complications documented that the majority were due to leaks from the esophageal repair. This led to wound infections, tracheoesophageal fistulas, secondary pneumonias, and blowouts of adjacent repairs of the carotid artery. With adjacent repairs of the trachea and esophagus, trachea and carotid artery, or esophagus and carotid artery, a vascularized sternocleidomastoid muscle flap should be used to cover the visceral repair145 (Fig. 22-9). This should lower the incidence of a leak from the visceral repair and, if a leak occurs, protect the adjacent arterial repair.
The sternal head of the left sternocleidomastoid muscle was interposed between tracheal and esophageal repairs after a gunshot wound in Zone II.
The sternocleidomastoid muscle has a tripartite blood supply that includes the thyrocervical trunk, superior thyroid artery, and occipital artery. Therefore, it can be detached from the sternum and clavicle inferiorly or the mastoid process superiorly and rotated to cover the repair of the trachea or esophagus and act as a vascularized buttress. With combined injuries of the trachea, esophagus, and/or carotid artery at the upper or mid-area of Zone II, the first step is detaching the sternal head of the sternocleidomastoid muscle from the sternum if the muscle is bulky. If it is not, both the sternal and clavicular attachments are divided. Either the detached sternal end or the entire muscle is then mobilized and rotated medially to buttress the tracheal or esophageal repair and separate it from the repair in the carotid artery. The mobilized muscle is sewn in place with multiple interrupted sutures of 3-0 absorbable material. Any esophageal repair is drained anteriorly with the drain track away from the repair in the carotid artery.