Esophageal perforation can be difficult to diagnose promptly. Delay in treatment results in a high mortality rate. There are sharp differences in etiology, presentation, treatment, and results of cervical versus thoracic perforation of the esophagus. Most cervical perforations respond well to simple drainage. Although the treatment of thoracic esophageal perforations is individualized, most patients are candidates for primary repair regardless of whether they are treated early or late.

ETIOLOGY

Esophageal perforation usually is the result of iatrogenic injury caused by instrumentation (e.g., esophagoscopy, bougienage, and achalasia dilation)^1–3 (Table 40-1). The most common site for perforation of the normal esophagus is at its most proximal location just above the cricopharyngeus muscle and below the inferior constrictor (Killian's triangle). The injury at this location usually is caused by attempted forceful intubation of the esophagus for endoscopy (rigid or flexible) in a patient who is not sufficiently anesthetized. Other common sites of perforation include those in which the esophagus is normally narrowed (the distal esophagus), pathologically narrowed, or anatomically abnormal. Occasionally, intramural perforation can occur when the mucosa is sheared off the muscularis during endoscopy or bougienage. These conditions are not perforations in the truest sense but present in a similar fashion and must be differentiated from frank perforation. Spontaneous perforation is a misnomer. It is more accurately termed barogenic perforation (Boerhaave's syndrome). Blunt and penetrating trauma contributes a small number of perforations.⁴ Foreign bodies, infections, and operative injuries are additional causes of perforation.⁵

DIAGNOSIS

Pain is prominent in patients presenting with esophageal perforation. Patients with cervical perforations usually present with neck pain, dysphagia, odynophagia, and dysphonia. Subcutaneous emphysema is often palpable in the neck. Pain from an intrathoracic perforation may be localized initially to the subxiphoid region and hence may be misinterpreted as a myocardial infarction, aortic dissection, perforated duodenal ulcer, or pancreatitis. The pain also may be substernal, referred to the back, or poorly localized, but it is usually severe. Dyspnea and anxiety are common findings in patients with esophageal perforation. Tachycardia is very common, and fever quickly develops. The frequency with which shock occurs, rarely seen after a cervical perforation, varies with the type of perforation and length of time after the original insult. With free perforation into the pleural space, as often occurs with Boerhaave's syndrome, rapid progression to shock may occur within 24 hours. Perforation by balloon dilation of achalasia similarly may result in a rapid and disastrous course if treatment is delayed. A small instrumental perforation, on the other hand, confined to the wall of the esophagus or situated in the mediastinum may lead to a much slower development of symptoms. The key feature in the diagnosis of esophageal perforation is a high level of suspicion. Prompt evaluation of patients with any of these findings or symptoms after endoscopy is most important because early diagnosis improves outcome.

RADIOLOGIC EVALUATION

A lateral plain neck film usually demonstrates air in the prevertebral space even early after cervical perforation (Fig. 40-1). Chest radiographs may show a pleural effusion, subcutaneous emphysema, pneumomediastinum, or pneumothorax. Radiographs soon after the event may be normal, but 75% of patients have abnormal radiographs within 12 hours. Examination of the esophagus with contrast material is preferably done with water-soluble medium (Figs. 40-2, 40-3, 40-4, and 40-5). Water-soluble contrast material may have a false-negative rate of 25–50%. If a question remains or the definition is inadequate, dilute barium may be used sparingly. The overall false-negative rate of contrast studies is at least 10%.³ If perforation is still strongly suspected, the test should be repeated several hours later, or another modality of investigation should be used. CT scans can help with the diagnosis of esophageal perforation and can identify the late sequelae of perforations.⁶ CT evidence of perforation may include extraluminal air, extravasation of contrast material, esophageal thickening, and communication of the air-filled esophagus with an adjacent structure (Fig. 40-6). Oral or nasogastric tube contrast material can be given just before CT scan to increase the detection rate of an esophageal perforation. Planning the diagnostic evaluation with a radiologist is recommended to avoid the administration of contrast material that may delay the use of CT. Endoscopy is helpful occasionally to either diagnose a perforation (usually in a trauma patient) or to assess the status of the esophagus in deciding which operation to perform. Important information that can be determined by endoscopy is the exact location of the tear, the presence of a stricture or other pathology, and the extent of a carcinoma. If carefully performed with a flexible endoscope by an experienced endoscopist/surgeon, there is no additional risk to performing esophagoscopy when potentially important information can be gained.

Intramural perforations can be a source of confusion to the inexperienced radiologist or surgeon. These are usually caused by instrumentation, when the mucosa is inadvertently sheared off the muscularis at the cricopharyngeus or a pathologically narrowed area. Intense pain is common. A barium swallow shows two lumens: the true lumen through which contrast material readily passes downward and a false lumen with contrast material pooled in a dependent pouch (Fig. 40-7). CT can help to clarify this diagnosis (Fig. 40-8). Critical to the early diagnosis of esophageal perforation is the physician's awareness of the possibility. Where instrumentation has preceded the development of any of these signs and symptoms, perforation must be suspected until proved otherwise.

TREATMENT

Factors important to selecting the appropriate treatment include the location, cause, status of the native esophagus, severity of the perforation, and time of perforation (Table 40-2). Treatment always involves vigorous general support of the patient, broad-spectrum antibiotics, and nutritional support. The general principles of treatment are to control or eliminate the esophageal leak, maintain or reestablish gastrointestinal tract continuity, eliminate infection, eliminate distal obstruction (if any), and drain or debride collections and devitalized tissue. Cervical perforations usually are best managed by immediate drainage of the retroesophageal space. This procedure is performed via the usual oblique neck incision along the border of the sternocleidomastoid muscle. The carotid sheath contents are retracted laterally and the visceral compartment medially. The left-sided approach is preferred to reduce the risk of recurrent nerve injury. Usually, an instrumental perforation is located directly posterior and is found easily. The cavity of contrast material, saliva, and infected contents should be drained and cleaned with irrigation. Additional tissue planes should not be opened if they are undisturbed. There is no need to search for the mucosal tear because the perforation will heal with proper drainage, antibiotics, and nutritional support. I generally place a passive Penrose drain in the cavity and an active suction drain if there is any dependent tracking of the infection into the mediastinum. The patient is kept nothing by mouth for a period of 5–7 days depending on clinical status. The drains may be removed either in the hospital or in an outpatient setting.

In thoracic perforations, conservative management is considered in two situations. One is a known, contained perforation which is demonstrated by contrast study and has already undergone a period of observation with no ill effects. The other perforation that is usually treated nonoperatively is an intramural perforation between mucosa and muscularis.

Cameron and associates suggested criteria for nonoperative treatment of esophageal perforation: (1) a contained perforation, (2) ready drainage back into the lumen, and (3) minimal symptoms.⁷ This series only had eight patients, and five of them had an esophagogastric leak after resection, thus invalidating the series with regard to treatment of true esophageal perforations. Only two patients had a barogenic perforation. All were managed nonoperatively and, after a period of observation, such that the patients were self-selected. The decision to provide nonoperative treatment is easy when there has already been a trial, so to speak, of supportive care only that has been successful. Far more difficult is the decision to pursue nonoperative treatment immediately after diagnosis. Altorjay and colleagues reported on 15 transmural perforations (they also reported 6 cases of intramural perforations) treated nonoperatively.⁸ Seventy percent were early perforations, and fifty percent were cervical. Four patients deteriorated and required operation. Two of fourteen patients died, for a mortality rate of 14%. These authors essentially endorsed Cameron's criteria but also added others: (1) circumscribed perforation; (2) contrast material flows back into lumen; (3) no cancer, obstruction, or abdominal esophageal leak; and (4) minimal signs and symptoms.

For most perforations of the thoracic esophagus that are diagnosed early (<24 hours), there is general agreement that operative repair is best.^9–12 A thoracotomy is performed on the side of the perforation at the expected interspace of the tear. The pleural space is thoroughly cleansed and the lung decorticated. The esophageal laceration is debrided in conservative fashion, the mucosa is meticulously closed with interrupted sutures, and the muscularis is similarly closed as a second layer¹² (Fig. 40-9). An alternative closure technique is to use a linear stapling device to close the mucosal tear¹¹ (Fig. 40-10). The mucosal tear often extends beyond that of the muscularis such that the surgeon must ensure that the two ends of the mucosal tear are well exposed. (This may necessitate extending the muscle tear by incising it to fully expose the underlying mucosal tear.) Buttressing, even of a fresh perforation, with healthy vascularized tissue of good consistency is advisable. The repair should be checked with instillation of a large volume of methylene blue-tinted saline injected into the esophagus via the nasogastric tube after completion of the suture lines. An optimal buttress is a pedicled intercostal muscle flap, preferably elevated at the time of entry into the chest, such that the vasculature to the muscle is intact. It should be sutured down as if it were being anastomosed to the esophageal wall rather than simply "tacked" over the closure. Other flaps that have been used are pericardial fat pad, diaphragm, chest wall muscle, omentum, and stomach wall folded over a low perforation. The pleura is not thickened sufficiently by inflammation in early perforation to be used effectively as a flap, although this has been mistakenly advised. Intercostal muscle has been used successfully as a primary patch, rather than as a buttress, in patients with rupture after balloon dilation for achalasia, in whom myotomy could not be employed and esophageal closure was impossible. The pleural space is well drained, and I place a large suction drain immediately adjacent to the repair site and leave this drain in place until a postoperative contrast swallow is done. Gastrostomy and jejunostomy are advisable, the first to keep the stomach empty to prevent reflux into the esophagus and the latter for long-term feeding. Any esophageal or pyloric obstruction must be relieved at operation, or reperforation is likely to occur. For the typical achalasia patient who is perforated during dilation, the perforation should be closed in the usual two layers and then a myotomy performed on the opposite side of the esophagus. The patient is kept nothing by mouth for at least a week, and then a contrast swallow is performed to ascertain whether the repair has been successful. If there is a small, contained leak after repair that is asymptomatic, usually just continued observation and maintenance of the nothing by mouth status is required (Fig. 40-11).

Resection for esophageal perforation generally has been restricted to perforations of carcinoma, sometimes as a result of biopsy or dilation or in rare cases of extensive necrosis of the esophagus from infection.^13,14 It also has been proposed as primary treatment for all intrathoracic perforations. This seems inadvisable because no esophageal substitute ever functions as well as the native esophagus. We believe that late perforations also should be treated surgically in almost every case. Surgery may be vastly more difficult because of inflammation and induration. However, the mucosa usually can be closed after limited debridement of its edges. Closure of the indurated muscular wall provides at best provisional closure for the purpose of accomplishing the surgery. The definitive sealing of the esophagus from the pleural space is accomplished by the use of a sturdy, well-vascularized tissue buttress applied as described earlier. Full expansion of the lung by decortication and cleansing of the pleural space is essential. In a particularly difficult situation, the diaphragm may be opened and the omentum brought up as a further buttress. The risk of transdiaphragmatic sepsis appears to be small. Another technique that is used for a late perforation is the insertion of a large T-tube in the esophagus with the sidearm brought out through the chest wall. This is rarely necessary, and the results are not predictable. Esophageal diversion is almost never desirable. This allegedly reversible procedure often may prevent salvage of a functional native esophagus, which is far superior to any eventual replacement. It was proposed because of the high incidence of releakage after primary repair, especially in late cases.¹⁵ Use of primary repair with meticulous buttressing obviates the need for diversion, except in a rare case of extensive esophageal destruction or necrosis. In such an instance, esophagectomy with delayed reconstruction is the best option. Continued irrigation per esophagus into the pleural space has been proposed to avoid operative repair.¹⁶ This seems a dubious choice. Endoesophageal stents have been used to close unresectable malignant perforations, postoperative leaks after esophagectomy, and even instrumental and barogenic perforations with some success.¹⁷ Stents seem counterintuitive because the opening one seeks to close is infected and has a foreign body next to it, but they have been reported to close a leak. The stent is left in for several months after placement, and then removal is attempted. Stent placement would seem a logical choice for patients in whom an operation would be particularly risky or in patients with advanced and unresectable esophageal cancer.

RESULTS

The overall mortality from a recent collected case series from 1990 to 2003 was 18%.³ The etiology of the perforation affected outcome. Barogenic perforations had a mortality of 36%, instrumental perforations 19%, and traumatic perforations 7%. The location of the perforation affected outcome as well. Cervical perforations had a mortality of 6%, whereas thoracic perforations had a mortality of 27%. Delay in treatment affected outcome, as would be expected. When treatment was initiated in the first 24 hours, the average mortality was 14%, whereas it was 27% if treatment was delayed beyond 24 hours. Finally, the type of treatment affected outcome. Primary repair had a mortality of 12%, resection 17%, drainage 36%, exclusion 24%, and nonoperative treatment 17%. These results have not changed appreciably since the last large case series review in 1992.¹

Older series suggested a benefit to using a tissue buttress, with a reduction in leak rates and mortality after primary repair.¹ More recent series have reported good results without use of a tissue buttress.¹¹ Our feeling is that adding a tissue buttress may help to contain a small postoperative leak and that the morbidity of taking an intercostal muscle for a flap is minimal. Of greater importance, we find, is the complete exposure of the mucosal tear with meticulous secure closure of both the mucosa and muscularis. Older series also suggested that primary repair should be undertaken only for early perforations and that exclusion or resection should be performed for late perforations. Again, recent reports suggest that primary repair is applicable whether performed early or late. As expected, the results are better with early repair, but most patients with late repairs also did well.

EDITOR'S COMMENT

It is important to diagnose and treat esophageal perforation early and aggressively to maximize survival. However, there remains a subset of patients who develop recurrent leak and sepsis secondary to delayed diagnosis and failure of esophageal repair. Two recent examples from my own practice include a patient who presented with Boerhaave's syndrome 48 hours after a perforation was explored via thoracotomy and repaired but continued to have low-grade sepsis for an additional week. A second elderly patient had a perforation from transesophageal echocardiography during open-heart surgery and was not diagnosed until 72 hours later. He also continued to have low-grade sepsis and leak despite standard repair. Both these patients benefited from esophageal diversion. One recently described technique is to bring a loop of the cervical esophagus to the neck and create a stoma without dividing the esophagus but defunctionalizing the distal limb.¹⁸ Another approach I have used is to staple the esophagus just above the gastroesophageal junction from either the abdomen or the chest and place a gastrostomy for feeding. The chest is also decorticated and drained. I have done this in two patients, and in both the sepsis was controlled, and the patients improved and were discharged. Three months later, I was able to close the proximal stoma and dilate the staple line endoscopically, yielding a normally functioning esophagus in each patient.

–RB

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