Core Topics in General & Emergency Surgery: Companion to Specialist Surgical Practice (29 page)

Classification

Perforation of the oesophagus can be broadly classified into iatrogenic and spontaneous. Iatrogenic perforations represent the most common cause of oesophageal perforation, with most occurring during diagnostic or therapeutic endoscopy, while some are related to para-oesophageal operations, such as fundoplication, cardiomyotomy, bariatric procedures, etc. The reported incidence of perforation for rigid oesophagoscopy is 0.11% and for fibre-optic endoscopy varies from 0.018% to 0.03%.
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Therapeutic endoscopy is associated with a much higher frequency of perforation (1–10%).
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Spontaneous rupture of the oesophagus (Boerhaave's syndrome) accounts for approximately 15% of perforations and classically occurs after forceful retching or vomiting, often related to an episode of binge eating and/or drinking.
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The perforation is typically located just proximal to the oesophagogastric junction and more commonly opens into the left pleural space. Other less common causes of oesophageal perforation include foreign body penetration, traumatic endotracheal intubation, nasogastric catheterisation and the swallowing of corrosives.

The overall mortality following oesophageal perforation was estimated to be 18% in a recent review covering 726 published patients.
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Paramount in the management of this highly lethal emergency is expedient diagnosis and judicious clinical management. However, the presentation can be non-specific and may easily be confused with other disorders such as spontaneous pneumothorax/pneumomediastinum, myocardial infarction, acute pancreatitis and pneumonia. The essential attribute is to maintain a high index of suspicion, especially if a normal laparotomy has been performed. Pain is the most common symptom, which may occur anywhere from the neck to the abdominal region, depending on the location, the cause and the time elapsed between onset and presentation. Less often, dysphagia, odynophagia, dyspnoea, cyanosis and fever are other possible complaints. A preceding history of forceful vomiting, oesophageal instrumentation, para-oesophageal surgery and chest trauma should always be taken into consideration. Physical examination and plain radiograph may reveal surgical emphysema over the neck and upper chest wall (
Fig. 6.4
). Hydrothorax or pneumothorax may also be found on erect chest X-ray (
Fig. 6.5
). Hamman's sign (a crunching sound heard on chest auscultation) is found less commonly than suggested in textbooks.

The role of ancillary investigations for oesophageal perforation depends largely on the condition of the patient. If a patient is relatively stable and requires no endotracheal intubation, a water-soluble contrast swallow is a relatively easy way to confirm the diagnosis, determine the location, and assess the severity of the perforation (
Fig. 6.6
). However, for patients with profound sepsis mandating intubation and ventilatory support, a contrast-enhanced CT scan of the suspected region will be required to help establish the diagnosis (
Fig. 6.7
). A careful flexible oesophagoscopy is a very useful technique when the diagnosis is in doubt after these other investigations and often before surgery, as it confirms the exact site and length of perforation.

The management of oesophageal perforation starts with aggressive resuscitation and close monitoring of the physiological parameters. Further contamination of the mediastinum is minimised by making the patient ‘nil by mouth’. Although insertion of a nasogastric tube reduces the potential for ongoing leakage from refluxed gastric contents, in the presence of a perforation that might be managed non-operatively (see below), this will need to be inserted either under direct vision (endoscopically) or using X-ray guidance. Vigorous intravenous fluid replacement and broad-spectrum antibiotics are prescribed for control of systemic infection, and antifungal therapy should also be considered. Chest drainage should be established if there is hydrothorax or hydropneumothorax and most patients require intensive care support. Subsequent management should be individualised according to the patient's clinical condition, the presence of comorbidities, the underlying oesophageal pathology, the location of perforation, and sometimes the time lapse between perforation and diagnosis. Nowadays, a multidisciplinary team approach involving medical, endoscopic and surgical management is increasingly adopted in the care of such patients.

Candidates for conservative treatment, as defined by Cameron and colleagues in 1979, include those with a small perforation that does not breach the mediastinal pleura, together with mild symptoms and no evidence of systemic sepsis.
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Preferably, the perforation is accompanied by a re-entry of extravasated contrast medium into the oesophageal lumen. Any sympathetic pleural effusion has to be drained, with the effluent regularly inspected to exclude fistulation. Nutritional support, either by the parenteral route or increasingly by the operative insertion of a feeding jejunostomy tube, is commenced early.

Previous experience suggests that patients who respond to non-operative management are those with small cervical tears following oesophagoscopy or traumatic endotracheal intubation, well-circumscribed intramural dissection after pneumatic dilatation for achalasia and small anastomotic leaks following oesophageal surgery.
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Non-operative treatment of spontaneous rupture (Boerhaave's syndrome) and iatrogenic perforation of the thoracic oesophagus with pleural contamination used to have a high failure rate in previously reported series and such patients were often managed by early surgical intervention. However, all this has changed over the last decade with the introduction of aggressive conservative strategy and the increasing interest in endoscopic stenting technology.

Vogel et al. were the first to advocate an ‘aggressive conservative’ approach in a series of 47 patients with oesophageal perforation (10 proximal and 37 thoracic).
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Of these 47 patients, 34 were managed non-operatively with repetitive radiographs, aggressive image-guided chest drainage and operative intervention when indicated (only needed in 30% of the patients). The authors reported no mortality and an admirably high oesophageal healing rate in the series, even among patients with Boerhaave's syndrome. In another cohort study by a tertiary referral centre of 81 consecutive patients with acute oesophageal perforation managed over a 20-year period, there was a marked temporal increase in the frequency of utilising CT scan for diagnosis and treatment monitoring of the patients. The percentage of patients being treated non-operatively also increased significantly from 0% in the first 5-year cohort to 75% in the last one.
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Parallel to these results was a marked reduction in complication rate and mean hospital stay. There was no difference in final mortality rates between patients treated with a non-operative approach and those who underwent immediate surgery.

One hindrance in promulgating wider use of the non-operative approach for oesophageal perforation lies in the difficulty of selecting appropriate candidates for this treatment while those who will benefit from early surgery are not delayed unnecessarily. The criteria set by Cameron et al. were far from evidence based, and the subsequent modification by Altorjay et al. also restricted non-operative management to patients with almost microperforation only.
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Recently, an oesophageal perforation severity scoring system has been suggested by the Pittsburgh group.
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Based on 10 clinical variables (old age, tachycardia, leucocytosis, pleural effusion, fever, non-contained leak, respiratory compromise, delay in diagnosis, cancer and hypotension), a maximum score of 18 can be derived at the time of admission. The prevalence of complications, mortality and the length of hospital stay were found to be significantly varied among groups with different scores (less than 2, 3–5 and more than 5). Notably the data suggested that patients with low clinical scores had worse outcomes if treated operatively when compared to those managed by the non-operative approach. These authors concluded that patients with a low clinical score, especially those with minimal mediastinal contamination and no respiratory distress, should be tried with aggressive non-operative treatment and surgical repair reserved for those with signs of deterioration.

An important adjunct now available in dealing with these ‘minor’ perforations is endoluminal stenting.
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The recent development of a retrievable type of silicone-coated stent has shown some promising results (
Fig. 6.8
). In a prospective series of 18 patients with iatrogenic perforation of the oesophagus, 17 were treated with the Polyflex (Boston Scientific, Natick, MA, USA) stent in addition to chest drainage.
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Except for one patient with a persistent leak who required operative repair, the remaining 16 had successful resolution of their perforations as confirmed by oesophagram. Most of the patients were able to resume oral intake in 72 hours, and the mean time before the stent was removed was 52 days. Alternatively, elderly and frail patients who suffer perforation following attempted dilatation of a malignant stricture can be managed by insertion of a covered permanent stent.

The technical success rate of stenting was 99% and clinical success was achieved in 85% of patients. Though 34% of the patients had a stent-related complication (mainly stent migration), surgical intervention was required in only 13%, in whom the rupture site failed to heal completely after 6–8 weeks of stenting. These stents should be removed as soon as possible to prevent longer-term problems.