Esophageal injuries: Principles of management

Incidence

The incidence of esophageal injuries is low with most resulting from penetrating trauma. Esophageal trauma received little notice until the completion of World War II, with only 18 esophageal injuries recorded in the military records reviewed from that war and the Korean and Vietnam Wars combined. Numerous reports in the literature document the incidence of esophageal trauma to be less than 1%, with penetrating wounds of the esophagus far outnumbering blunt esophageal injuries. The predominant mechanism responsible for esophageal trauma injury is gunshot wounds (70%-80%) followed by stab wounds (15%-20%) and shotgun wounds (3%-5%). Esophageal injuries resulting from blunt trauma account for less than 1% of all esophageal injuries and are quite rare. These injuries are most often located in the cervical esophagus as the result of an anterior blow with the neck in a hyperextended position. An acute blow to a distended stomach may produce tears of the distal esophagus, with the most common cause being penetrating injuries sustained from stab and gunshot wounds.

The cervical esophagus represents the most common site of injury followed by thoracic and abdominal esophageal injuries. Thoracic wounds are relatively uncommon in patients who present to the hospital alive, given the proximity of the esophagus to the aorta and its relative protection by the thoracic by vertebrae. The abdominal esophagus measures only 2 to 3 cm, making injuries uncommon. Virtually all patients who sustain an esophageal injury also incur associated injuries to other respiratory, gastrointestinal, and vascular structures. As a result, trauma surgeons must maintain a high index of suspicion so that untoward diagnostic delays may be avoided. Although these wounds occur relatively infrequently, they continue to be associated with a significant mortality rate.

Diagnosis

Diagnostic delays are often cited as significant factors in the high morbidity and mortality rates associated with injuries to the esophagus. Several factors contribute to this diagnostic delay including the uncommon occurrence of these injuries. Because associated injuries are common, delays may occur before the initiation of specific diagnostic tests to evaluate the esophagus. All the while, even a “simple” perforation elicits a massive inflammatory response with mediastinal tissue destruction that may further complicate the integrity of repair.

Esophageal injuries must be suspected in penetrating neck injuries that violate the platysma, in transmediastinal gunshot wounds, and following significant chest trauma with associated tracheobronchial injuries. The clinical findings most commonly associated with cervical esophageal injuries include neck pain and dysphagia. Tenderness to palpation and with passive motion, dyspnea, and hoarseness may be present. Hematemesis, hemoptysis, or bloody nasogastric tube aspirate in the absence of obvious oral or pharyngeal trauma should suggest the possibility of esophageal injury. Expanding cervical hematoma is certainly a cause for concern as are the subsequent development of fever, cough, and stridor. Palpable crepitus or air within the soft tissues or a wide prevertebral shadow on neck or cervical spine radiographs may provide the initial suggestion of an esophageal injury. Computed tomography examination may demonstrate subcutaneous emphysema within the soft tissues or in the upper mediastinum.

The clinical findings associated with thoracic esophageal injuries may be nonspecific and initially absent. They may include abdominal tenderness or rigidity, cervical crepitus from tracking of mediastinal emphysema, and Hamman sign (mediastinal crunch on auscultation). The presence of mediastinal emphysema and pleural effusion in the face of penetrating thoracic trauma should elevate awareness for the possibility of a thoracic esophageal injury.

Subdiaphragmatic esophageal injuries often present with abdominal tenderness or rigidity. Patients frequently complain of abdominal pain and may progress to signs of frank peritonitis. Upright chest radiographs or computed tomography scans may demonstrate pneumoperitoneum.

Although penetrating neck or thoracic wounds with hemodynamic instability often necessitate immediate exploration for associated injuries, the hemodynamically stable patient often presents a diagnostic challenge. In the past, all penetrating neck wounds that violated the platysma were routinely explored. However, most trauma centers now practice selective management of neck wounds. Selective management necessitates some type of study to exclude esophageal injury. We recommend a water-soluble contrast esophagogram in stable patients. If no injury is seen, addition of dilute barium adds a measure of safety in excluding an injury. Because contrast studies yield a false-negative rate of up to 25%, esophagoscopy may be added in patients regarded as high risk for injury. The specificity of a negative esophagogram accompanied by negative esophagoscopy approaches 100%. Even in hemodynamically stable patients with cervical hematomas who undergo exploration, we advocate esophagoscopy, as the injury may be further localized by the appreciation of blood or hematoma within the esophagus. It is often difficult to identify an esophageal injury during exploration due to extensive blood staining of the tissues. All studies should be obtained in an expeditious manner as prolonged time to diagnosis has been widely correlated with increased morbidity and mortality rates. Once an esophageal injury has been diagnosed, all oral intake is held, careful nasogastric tube decompression is performed, and intravenous fluid resuscitation and broad-spectrum antibiotics are initiated before prompt surgical intervention.

Surgical treatment

Although some penetrating cervical wounds may be managed nonoperatively, all confirmed esophageal injuries should be managed operatively in expedient fashion. The preferred surgical management of esophageal injuries is dictated by the location of the injury, stability of the patient, time to diagnosis, and associated injuries.

In our opinion, all esophageal injuries should be treated by general unifying principles regardless of location. These principles include (1) attempted closure of all defects by some method; (2) the use of onlay flaps, preferably muscular, as a buttress or for primary closure; and (3) tube drainage near the repair. Given the lack of a serosa, primary healing of the esophagus is not uniform. Therefore, the use of a buttress often enhances healing without fistula development. Local muscle flaps, in particular, are useful for either buttress or as a primary onlay repair.

Injuries to the cervical esophagus may be approached either by a collar incision or by an incision anterior to the sternocleidomastoid. An anterior unilateral incision should be made for unilateral cervical and single injuries, whereas a collar incision is indicated for midline, multiple, or bilateral cervical injuries. The esophagus is located deep to the trachea, and placement of a nasogastric tube often facilitates localization by palpation. Throughout the dissection, great care must be taken to identify and avoid injury to the recurrent laryngeal nerves, which are located in the tracheoesophageal groove. If further exposure is needed, the omohyoid muscle may be divided. After blunt dissection, the esophagus should be encircled by a Penrose drain or similar device in order to further facilitate the dissection.

Thoracic esophageal injuries are best approached through thoracotomy incisions based on the suspected level of the injury. Following initial studies, the decision for the incision should be determined by the presence of pleural effusion or defined leak identified on esophagogram. Injuries to the upper two thirds of the thoracic esophagus are best approached through a right posterolateral thoracotomy though the fifth intercostal space, as superior thoracic injuries may be difficult to expose due to the aortic arch. Injuries to the lower third of the thoracic esophagus are best approached through an incision in the left sixth intercostal space.

Injuries to the abdominal esophagus should be approached through a laparotomy incision, with the left side of the chest prepped into the operative field should a thoracic approach be necessitated. Additional exposure can be achieved by placing the patient in the Trendelenburg position and by mobilizing the left lobe of the liver. The midline incision can be extended superiorly and to the left of the xiphoid process for an additional 1 to 2 cm of exposure. The esophagus should be exposed with blunt manual dissection at the gastroesophageal junction and encircled with a Penrose drain. The hiatus can be widened, if necessary, to expose wounds near the gastroesophageal junction.

While many injuries of the esophagus can be primarily repaired if promptly diagnosed, we always recommend a buttress of this repair. Small injuries may be closed transversely, whereas injuries larger than 2 to 3 cm can be closed longitudinally in order to avoid undue tension. Unfortunately, diagnostic delay often yields significant mediastinal inflammation and sepsis. Furthermore, the lack of a serosal layer complicates primary reapproximation as the esophageal tissues are extremely friable especially under these circumstances. Primary closure after a period of a few hours rarely is successful. Numerous strategies have been proposed including nonoperative management with drainage, esophageal resection, and diversion with exclusion. The use of pleural flaps has been widely described for buttressing primary repairs. More recently, various muscle flaps have been advocated for primary repair of esophageal defects and as a buttress to suture repair.