Chapter 23 Esophagus and Diaphragmatic Hernia
Principles of Surgery Companion Handbook
ESOPHAGUS AND DIAPHRAGMATIC HERNIA
|Gastroesophageal Reflux Disease|
|Indications for Antireflux Surgery|
|Motility Disorders of the Pharynx and Esophagus|
|Motility Disorders of the Esophageal Body and Lower Esophageal Sphincter|
|Cancer of the Esophagus|
|Benign Tumors and Cysts of the Esophagus|
|Miscellaneous Esophageal Lesions|
|Techniques of Esophageal Reconstruction|
The esophagus is a muscular tube that starts as the continuation of the pharynx and ends as the cardia of the stomach. The esophagus lies in the midline but deviates to the left in the lower portion of the neck and returns to the midline near the bifurcation of the trachea. In the lower thorax, the esophagus again deviates to the left to pass through the diaphragmatic hiatus (Fig. 23-1).
FIGURE 23-1 Important clinical endoscopic measurements of the esophagus in adults. (From: Rothberg M, DeMeester TR: Surgical anatomy of the esophagus, in Shields TW (ed): General Thoracic Surgery, 3d ed. Philadelphia, Lea & Febiger, 1989, p 78, with permission.)
Three normal areas of esophageal narrowing are evident on the barium esophagogram. The uppermost is caused by the cricopharyngeal muscle. The middle narrowing is caused by the crossing of the left mainstem bronchus and aortic arch. The lowermost narrowing is caused by the gastroesophageal sphincter mechanism. These constrictions tend to hold up swallowed foreign objects and corrosive liquids because of their slow passage through these areas.
The cervical portion of the esophagus is approximately 5 cm long and descends between the trachea and the vertebral column to the level of the suprasternal notch anteriorly. The recurrent laryngeal nerves lie in the right and left grooves between the trachea and the esophagus. On the left and right sides of the cervical esophagus are the carotid sheaths and the lobes of the thyroid gland.
The thoracic portion of the esophagus is approximately 20 cm long. In the upper thorax, it is in intimate relationship with the posterior wall of the trachea and the prevertebral fascia. Just above the tracheal bifurcation, the esophagus passes to the right of the aorta. From the bifurcation of the trachea downward, both the vagal nerves and the esophageal nerve plexus lie on the muscular wall of the esophagus.
The thoracic esophagus follows the curvature of the spine and remains in close contact with the vertebral bodies. In the thorax, the thoracic duct lies dorsal to the esophagus between the azygos vein on the right and the descending thoracic aorta on the left.
The abdominal portion of the esophagus is approximately 2 cm long. This portion of the esophagus is subjected to the positive-pressure environment of the abdomen.
The musculature of the esophagus can be divided into an outer longitudinal and an inner circular layer. The upper 26 cm of the esophagus contains only striated muscle fibers. More distally, smooth muscle fibers gradually become more abundant. Most of the clinically significant esophageal motility disorders involve only the smooth muscle in the lower two-thirds of the esophagus.
The circular muscle layer of the esophagus is thicker than the outer longitudinal layer. The geometry of the circular muscle is helical and makes the peristalsis of the esophagus assume a wormlike drive as opposed to segmental and sequential squeezing. As a consequence, severe motor abnormalities of the esophagus assume a corkscrew-like pattern on the barium swallow radiogram.
The cervical portion of the esophagus receives its main blood supply from the inferior thyroid artery. The thoracic portion receives its blood supply from the bronchial arteries. Two esophageal branches arise directly from the aorta. The abdominal portion of the esophagus receives its blood supply from the ascending branch of the left gastric artery and from the inferior phrenic arteries. On entering the esophagus, the arteries form a longitudinal plexus, giving rise to an intramural vascular network in the muscular and submucosal layers.
The esophageal veins empty into the inferior thyroid vein, into the bronchial, azygos, or hemizygous vein, and into the coronary vein. The submucosal venous networks of the esophagus and stomach are in continuity with each other, and in portal venous obstruction, this communication functions as a collateral for portal blood to enter the superior vena cava via the azygos vein.
The parasympathetic innervation of the pharynx and esophagus is provided mainly by the vagus nerves. The cricopharyngeal sphincter and the cervical portion of the esophagus receive branches from both recurrent laryngeal nerves. Damage to these nerves interferes not only with function of the vocal cords but also with function of the cricopharyngeal sphincter, predisposing to pulmonary aspiration.
Afferent visceral sensory pain fibers from the esophagus using a combination of sympathetic and vagal pathways are also occupied by afferent visceral sensory fibers from the heart; hence both organs have similar symptomatology.
The lymphatics located in the submucosa of the esophagus are dense and constitute a single plexus. Lymph flow runs in a longitudinal direction. In the upper two-thirds of the esophagus the lymphatic flow is mostly cephalad and in the lower third caudad. In the thoracic portion of the esophagus, the submucosal lymph plexus extends over long distances in a longitudinal direction before penetrating the muscle layer. The cervical esophagus has a more direct segmental lymph drainage into the regional nodes.
Lymphatics from the cervical esophagus drain into the paratracheal and deep cervical lymph nodes and those from the upper thoracic esophagus empty mainly into the paratracheal lymph nodes. Efferent lymphatics from the lower thoracic esophagus drain into the subcarinal nodes and nodes in the inferior pulmonary ligaments. The superior gastric nodes receive lymph not only from the abdominal portion of the esophagus but also from the adjacent lower thoracic segment.
The tongue and pharynx function as a piston pump with three valves. The esophagus and cardia function as a worm-drive pump with a single valve (Fig. 23-2). The three valves in the pharyngeal cylinder are the soft pallet, the epiglottis, and the cricopharyngeus. The valve of the esophageal pump is the lower esophageal sphincter. Failure of the valves or the pumps leads to abnormalities in swallowing.
FIGURE 23-2 Intraluminal esophageal pressures in response to swallowing. (From: Waters PF, DeMeester TR, Med Clin North Am 65:1238, 1981, with permission.)
Swallowing, once initiated, is entirely a reflex. With the posterior movement of the tongue, the soft palate is elevated. This prevents pressure generated in the oropharynx from being dissipated through the nose. During swallowing, the backward tilt of the epiglottis covers the opening of the larynx to prevent aspiration.
During swallowing, a sizable pressure difference develops between the hypopharyngeal pressure and the less-than-atmospheric midesophageal or intrathoracic pressure. This pressure gradient speeds the movement of food. The bolus is propelled by peristaltic contraction of the posterior pharyngeal constrictors and sucked into the thoracic esophagus. When esophageal compliance is lost because of muscle pathology, dysphagia can result.
Swallowing can be started at will, or it can be reflexly elicited by the stimulation of areas in the mouth and pharynx. The swallowing center in the medulla coordinates the complete act of swallowing by discharging impulses through cranial nerves V, VII, X, XI, and XII, as well as the motor neurons of C1 to C3. Operative damage to the innervation can interfere with laryngeal, cricopharyngeal, and upper esophageal function and predispose the patient to aspiration.
The lower esophageal sphincter (LES) provides a pressure barrier between the esophagus and stomach. Sphincter-like function is related to the architecture of the muscle fibers at the junction of the esophageal tube with the gastric pouch. The LES actively remains closed to prevent reflux of gastric contents into the esophagus and opens by a relaxation that coincides with a pharyngeal swallow.
The antireflux mechanism in human beings is composed of three components: a mechanically effective LES, efficient esophageal clearance, and an adequately functioning gastric reservoir. A defect of any one of these three components can lead to increased esophageal exposure to gastric juice and the development of mucosal injury.
Physiologic Reflux Healthy individuals have occasional episodes of gastroesophageal reflux. They are more common when awake and in the upright position than during sleep in the supine position. Normal subjects rapidly clear the acid gastric juice from the esophagus regardless of their position. LES pressure in normal subjects is significantly higher in the supine position than in the upright position. This is due to the hydrostatic pressure of the abdomen to the abdominal portion of the sphincter when supine.
The LES has intrinsic myogenic tone, which is modulated by neural and hormonal mechanisms. Beta blockers stimulate the LES, and alpha-blockers decrease its pressure. Peppermint, chocolate, coffee, ethanol, and fat are all associated with decreased LES pressure and may be responsible for esophageal symptoms after a sumptuous meal.
Tests to Detect Structural Abnormalities Radiographic Evaluation The first test in patients with suspected esophageal disease should be a barium swallow followed by full assessment of the stomach and duodenum. Esophageal motility is optimally assessed in the horizontal position. Hiatal hernias are best demonstrated with the patient prone because the increased intraabdominal pressure promotes displacement of the esophagogastric junction above the diaphragm. Fully distended views of the esophagogastric region are crucial. Esophageal disorders shown well by a full-column technique include circumferential carcinomas, peptic strictures, large esophageal ulcers, and hiatal hernias. The full-column technique should be supplemented with mucosal relief or double-contrast films to enhance detection of smaller or more subtle lesions.
The radiographic assessment of the esophagus is not complete unless the entire stomach and duodenum have been examined. A gastric or duodenal ulcer, partially obstructing gastric neoplasm, or scarred duodenum and pylorus may contribute significantly to symptoms otherwise attributable to an esophageal abnormality.
Endoscopic Evaluation In any patient complaining of dysphagia, esophagoscopy is indicated even in the face of a normal radiographic study. The flexible esophagoscope is the instrument of choice because of its technical ease, patient acceptance, and the ability to simultaneously assess the stomach and duodenum. The rigid esophagoscope may be an essential instrument when deeper biopsies are required or the cricopharyngeus and cervical esophagus need closer assessment.
When gastroesophageal reflux disease is suspected, particular attention should be paid to the presence of esophagitis and Barrett's columnar-lined esophagus. Grade I esophagitis is defined as reddening of the mucosa without ulceration. Grade II esophagitis is defined by the presence of linear erosions lined with granulation tissue. Grade III esophagitis represents a more advanced stage where the linear ulcerations coalesce, leaving islands of epithelium. Grade IV esophagitis is the presence of a stricture.
Barrett's esophagus is a condition in which the tubular esophagus is lined with specialized columnar epithelium as opposed to the normal squamous epithelium. Its presence is confirmed by biopsy. Barrett's esophagus is susceptible to ulceration, bleeding, stricture formation, and most important, malignant degeneration.
A hiatal hernia is determined by a pouch lined with gastric rugal folds lying 2 cm or more above the margins of the diaphragmatic crura. When a submucosal mass is identified, biopsies are usually not taken. If a biopsy is taken, the mucosa may become fixed to the underlying abnormality. This complicates the surgical dissection by increasing the risk of mucosal perforation.
Tests to Detect Functional Abnormalities Stationary Manometry Esophageal manometry is a widely used technique to examine the motor function of the esophagus and its sphincters. It is particularly necessary to confirm the diagnosis of specific primary esophageal motility disorders, i.e., achalasia, diffuse esophageal spasm, nutcracker esophagus, and hypertensive LES. It also identifies nonspecific esophageal motility abnormalities and motility disorders secondary to systemic disease such as scleroderma, dermatomyositis, polymyositis, or mixed connective tissue disease. In patients with gastroesophageal reflux, manometry can identify a mechanically defective LES and evaluate the adequacy of esophageal peristalsis and contraction amplitude.
A mechanically defective LES is identified by having one or more of the following characteristics: an average LES pressure of less than 6 mmHg, an average length exposed to the positive-pressure environment in the abdomen of 1 cm or less, or an average overall sphincter length of 2 cm or less.
24-Hour Ambulatory Manometry In both normal volunteers and symptomatic patients, esophageal motor activity increases with the state of consciousness and focus on eating activity. In patients with nonobstructive dysphagia, the circadian esophageal motor pattern is characterized by an inability to organize the motor activity into peristaltic contraction during a meal period. In patients with noncardiac chest pain, ambulatory motility monitoring can document a direct correlation of abnormal esophageal motor activity with the symptom and shows that the abnormal motor activity immediately preceding the pain episodes is characterized by an increased frequency of simultaneous, double- and triple-peaked, high-amplitude, and long contractions. In patients with gastroesophageal reflux disease, ambulatory motility monitoring shows that the contractility of the esophageal body deteriorates with increasing severity of esophageal mucosal injury, compromising the clearance function of the esophageal body. The combination of ambulatory 24-h esophageal manometry with esophageal and gastric pH monitoring is currently the most physiologic way to assess patients with foregut motility disorders.
Esophageal Transit Scintigraphy The esophageal transit of a 10-mL water bolus containing technetium-99m (99mTc) sulfur colloid is recorded with a gamma camera. Its best use is to quantify the effect of an esophageal motility disorder by measuring esophageal emptying time.
Video- and Cineradiography High-speed cinematic or video recording of radiographic studies allows reevaluation by reviewing the study at various speeds. Observations suggesting dysfunction include misdirection of barium into the trachea or nasopharynx, prominence of the cricopharyngeal muscle, a Zenker's diverticulum, a narrow pharyngoesophageal segment, and stasis of the contrast medium in the valleculae or hypopharyngeal recesses. The simultaneous computerized capture of videofluoroscopic images and manometric tracings is now available and is referred to as manofluorography. It is presently the best means available to evaluate complex functional abnormalities.
Tests to Detect Increased Exposure to Gastric Juice The most direct method of measuring increased esophageal exposure to gastric juice is by an indwelling pH electrode. A 24-h period is necessary so that measurements are made over one complete circadian cycle. The 24-h esophageal pH monitoring should not be considered a test for reflux but rather a measurement of the esophageal exposure to gastric juice. The detection of increased esophageal exposure to acid gastric juice is more dependable than the detection of increased exposure to alkaline gastric juice. The presence of duodenal contents within the esophagus can now be determined via an indwelling spectrophotometric probe capable of detecting bilirubin over a 24-h period.
Standard Acid Reflux Test The development of powerful acid reduction agents such as omeprazole has created difficulties in the measurement of esophageal acid exposure. Standard acid reflux testing (SART) is performed following manometry by placing a pH electrode 5 cm above the upper border of the LES. The manometry catheter is then advanced temporarily into the stomach, and 300 mL of 0.1 N HCl is infused. The pH of the esophagus is monitored while the patient performs deep breathing, Valsalva and Mueller maneuvers, and coughs. A decrease in esophageal pH to less than 4 is considered evidence of reflux.
Patients with severe reflux may be unable to clear acid from the esophagus after reflux has been documented. SART has a sensitivity of 59 percent and a specificity of 98 percent and an overall accuracy of 81 percent.
Radiographic Detection of Gastroesophageal Reflux The radiographic demonstration of spontaneous regurgitation of barium into the esophagus in the upright position is a reliable indicator that reflux is present.
Tests for Duodenogastric Function Abnormalities of the gastric reservoir or increased gastric acid secretion can be responsible for increased esophageal exposure to gastric juice. Reflux of alkaline duodenal juice, including bile salts, pancreatic enzymes, and bicarbonate, is thought to have a role in the pathogenesis of esophagitis and complicated Barrett's esophagus. Duodenogastric function is assessed by studying gastric emptying with radionuclide-labeled meal, by gastric analysis, cholescintigraphy, and 24-h gastric pH monitoring.
GASTROESOPHAGEAL REFLUX DISEASE
Gastroesophageal reflux accounts for approximately 75 percent of esophageal pathology. Heartburn, or acid regurgitation, is very common. Even when excessive, these symptoms can be caused by achalasia, diffuse spasm, esophageal carcinoma, pyloric stenosis, cholelithiasis, gastritis, gastric or duodenal ulcer, and coronary artery disease. Gastroesophageal reflux can present with atypical symptoms, such as nausea, vomiting, postprandial fullness, chest pain, choking, chronic cough, wheezing, or hoarseness. Bronchiolitis, recurrent pneumonia, idiopathic pulmonary fibrosis, and asthma can be due primarily to gastroesophageal reflux disease. An alternative definition for gastroesophageal reflux disease is the presence of endoscopic esophagitis. Using this criterion assumes that all patients who have esophagitis have excessive regurgitation of gastric juice into their esophagus (Fig. 23-3). This is true in 90 percent of patients, but in 10 percent the esophagitis has other causes.
FIGURE 23-3 Proposed mechanisms of the progression of gastroesophageal reflux disease.
A third approach to define gastroesophageal reflux disease is to measure the basic pathophysiologic abnormality of the disease, i.e., increased exposure of the esophagus to gastric juice.
Etiology There are three known causes of increased esophageal exposure to gastric juice in patients with gastroesophageal reflux disease: a mechanically incompetent LES, inefficient esophageal clearance of refluxed gastric juice, and abnormalities of the gastric reservoir that augment physiologic reflux.
The Lower Esophageal Sphincter Failure of the LES is caused by inadequate pressure or overall length or abnormal position. Failure of all three sphincter components inevitably leads to increased esophageal exposure to gastric juice.
The most common cause of a mechanically defective LES is inadequate sphincter pressure. Sphincter pressure depends on the length and tension properties of the sphincter's smooth muscle. An adequate abdominal length is important in preventing reflux caused by increases in intraabdominal pressure. Reflux can occur whenever an increase in gastric pressure exceeds the sphincter pressure that is necessary to provide competency for the overall length of sphincter present.
Esophageal Clearance A second portion of the antireflux mechanism in human beings is effective esophageal clearance. Ineffectual clearance is more apt to be seen in association with a mechanically defective sphincter, where it augments the esophageal exposure to gastric juice by prolonging the duration of each reflux episode.
Four factors important in esophageal clearance are gravity, esophageal motor activity, salivation, and anchoring of the distal esophagus in the abdomen. The bulk of refluxed gastric juice is cleared from the esophagus by primary peristaltic waves initiated by a pharyngeal swallow. Manometry of the esophageal body can detect failure of esophageal clearance by analysis of the pressure amplitude and speed of wave progression through the esophagus.
Salivation contributes to esophageal clearance by neutralizing the minute amount of acid that is left following a peristaltic wave. Saliva production also may be increased by the presence of acid in the lower esophagus. This is referred to as water brash.
The presence of a hiatal hernia also can contribute to an esophageal propulsion defect due to loss of anchorage of the esophagus in the abdomen. The presence of a hiatal hernia contributes to the pathogenesis of gastroesophageal reflux disease.
Gastric Reservoir Abnormalities of the gastric reservoir that increase esophageal exposure to gastric juice include gastric dilatation, increased intragastric pressure, persistent gastric reservoir, and increased gastric acid secretion. The effect of gastric dilatation is to shorten the overall length of the LES, resulting in a decrease in the sphincter resistance to reflux.
Increased intragastric pressure occurs from the outlet obstruction of a scarred pylorus or duodenum, a vagotomy, and in the diabetic patient with gastroparesis. A persistent gastric reservoir results from delay of gastric emptying and increases the exposure of the esophagus to gastric juice by accentuating physiologic reflux. It is caused by gastric atony, advanced diabetes, diffuse neuromuscular disorders, anticholinergic medications, and postviral infections, vagotomy, antropyloric dysfunction, and duodenal dysmotility. Gastric hypersecretion can increase esophageal exposure to gastric acid juice by reflux of concentrated gastric acid.
Complications of Gastroesophageal Reflux Complications due to repetitive reflux are esophagitis, stricture, Barrett's esophagus, and progressive pulmonary fibrosis due to repetitive aspiration. The mechanical defect of the sphincter is primary and not the result of inflammation or tissue damage. Unrestricted reflux of gastric juice into the esophagus leads to mucosal injury with progressive deterioration of esophageal contractility and regurgitation into the pharynx with aspiration. The presence and severity of reflux complications are related to the presence of a mechanically defective sphincter and an increased esophageal exposure to both acid and alkalinity. Gastroesophageal reflux disease is significantly worse in patients with acid/alkaline reflux as compared with those with only acid reflux. Duodenal-gastric reflux and the acid secretory capacity of the stomach interrelate by altering the pH and enzymatic activity of the refluxed gastric juice to modulate the injurious effects of enzymes on the esophageal mucosa.
The disparity in injury caused by acid and bile alone as opposed to gross esophagitis caused by pepsin and trypsin explains the poor correlation between the symptoms of heartburn and endoscopic esophagitis. The reflux of acid gastric juice contaminated with duodenal contents could break the esophageal mucosal barrier, causing severe heartburn. Changing the pH of refluxed duodenogastric juice from acid to alkaline by the administration of histamine H2 blockers may intensify the mucosal injury while giving the patient a sense of security by alleviating the symptom of heartburn.
When esophageal injury occurs, a luminal stricture and/or Barrett's esophagus can develop by replacement of repetitively destroyed squamous mucosa with columnar epithelium. Endoscopically, the Barrett's changes can be associated with esophagitis, stricture, Barrett's ulceration, or dysplasia. Barrett's epithelium may become dysplastic and progress to adenocarcinoma with an incidence between 0.5 and 10 percent.
Esophageal stricture occurs at the site of maximal inflammatory injury, i.e., the columnar-squamous epithelial interface. As the inflammation extends higher, the stricture moves progressively up the esophagus. In patients with normal acid exposure, the stricture may be due to a drug-induced chemical injury resulting from the lodgment of a capsule or tablet in the distal esophagus. Long, stringlike strictures as a result of repetitive caustic injury from a capsule or tablet are often resistant to dilatation. Refluxed gastric juice can reach the pharynx with pharyngeal tracheal aspiration, causing cough, choking, hoarseness, and recurrent pneumonia. In patients with increased esophageal acid exposure, if the pH is below 4 for 1 percent of the time in the cervical esophagus, there is a high probability that the respiratory symptoms have been caused by aspiration.
Gastroesophageal reflux disease is such a common condition that most patients with mild symptoms carry out self-medication. Patients should be advised to elevate the head of the bed, avoid tight clothing, eat small frequent meals, avoid eating their nighttime meal soon before retiring, lose weight, and avoid alcohol, coffee, chocolate, and peppermints.
Alginic acid reacts with sodium bicarbonate in saliva to form a viscous solution that protects the esophagus against the noxious gastric contents. Medications to promote gastric emptying, such as metoclopramide, domperidone, and cisapride, have been of little value in severe disease.
In patients with persistent symptoms, the mainstay of medical therapy is acid suppression. High doses of proton pump inhibitors, such as omeprazole, can reduce gastric acidity by 8090 percent. With severe esophagitis, healing may occur in only half of patients. Within 6 months of discontinuation of any form of medical therapy for gastroesophageal reflux disease, 80 percent of patients have a recurrence of symptoms.
Patients whose symptoms persist despite simple antacid therapy should undergo endoscopy to determine if the complications of reflux disease such as esophagitis, stricture, or Barrett's esophagus are present. All are then placed on histamine H2 or omeprazole therapy. If their symptoms disappear completely after 12 weeks of therapy, the medication should be discontinued and the patient observed. If their symptoms recur within 4 weeks, they should be studied with manometry and 24-h foregut pH monitoring. Patients who on repeat endoscopy show persisting complications of the disease also should be studied. Depending on the results of the tests, further intensive medical therapy may be instituted, or the patient may be considered for surgical therapy if the criteria are met. Patients whose symptoms do not recur within 4 weeks and are free of complications of the disease should be monitored and treated intermittently when symptoms occur.
Indications for Antireflux Surgery
Before proceeding with an antireflux procedure, it is necessary to confirm that the patient's symptoms are caused by increased esophageal exposure to gastric juice secondary to a mechanically defective LES. This requires performing esophageal function studies, i.e., 24-h esophageal pH monitoring and esophageal manometry. Patients with increased esophageal acid exposure, a mechanically defective LES, and no complications of the disease should be given the option of surgery if they are drug dependent to control their symptoms.
If the patient responds symptomatically to medical therapy but endoscopic esophagitis persists, surgery should be performed. Without surgery, these patients can progress to develop a stricture or Barrett's esophagus.
Anatomic shortening of the esophagus can compromise the ability to do an adequate repair without tension and lead to an increased incidence of breakdown or thoracic displacement of the repair. When present, the motility of the esophageal body must be evaluated carefully, and if it is adequate, a gastroplasty should be performed. In patients who have absence of contractility or more than 50 percent interrupted or dropped contractions or a history of several failed previous antireflux procedures, esophageal resection should be considered as an alternative.
The surgeon should query the patient for specific complaints of epigastric pain, nausea, vomiting, and loss of appetite. These can be due to excessive duodenogastric reflux, which occurs in about one-third of patients with gastroesophageal reflux disease. In these patients, 24-h pH monitoring of the stomach may help to detect and quantitate duodenogastric reflux. If the symptoms of duodenogastric reflux persist after antireflux surgery, the administration of sucralfate may relieve the persistent complaint of nausea and epigastric pain.
Approximately 30 percent of patients with proven gastroesophageal reflux on 24-h pH monitoring will have hypersecretion on gastric analysis. These factors may modify the proposed antireflux procedure in patients with active ulcer disease or documentation of previous ulceration by the addition of a highly selective vagotomy.
Delayed gastric emptying is found in approximately 40 percent of patients with gastroesophageal reflux disease. Only in patients with severe emptying disorders is there a need for an additional gastric procedure.
Principles of Surgical Therapy (Fig. 23-4) The primary goal of antireflux surgery is to safely reestablish the competency of the cardia. First, the operation should restore the pressure of the distal esophageal sphincter to a level twice resting gastric pressure. Second, the operation should place an adequate length of the distal esophageal sphincter in a positive-pressure environment of the abdomen. Third, the operation should allow the reconstructed cardia to relax on deglutition. Fourth, the fundoplication should not increase the resistance of the relaxed sphincter to a level that exceeds the peristaltic power of the body of the esophagus. Fifth, the operation should ensure that the fundoplication can be placed in the abdomen without undue tension and maintained there by approximating the crura of the diaphragm above the repair.
FIGURE 23-4 Conceptual schema of the ideal treatment at each stage of the spectrum of gastroesophageal reflux disease.
PRIMARY ANTIREFLUX REPAIRS
The most common antireflux procedure is the Nissen fundoplication using only the gastric fundus to envelope the esophagus in performing the fundoplication, sizing the fundoplication with a No. 60 French bougie, and limiting the length of the fundoplication to 12 cm.
In the presence of altered esophageal motility, where the propulsive force of the esophagus is not sufficient to overcome the outflow obstruction of a complete fundoplication, a partial fundoplication may be indicated (the Belsey Mark IV repair).
In patients with a short esophagus due to stricture, Barrett's esophagus, or a large hiatal hernia, a Collis gastroplasty is performed as an esophageal lengthening procedure. The gastroplasty will lengthen the tubular esophagus by constructing a gastric tube, allowing tension-free construction of a Belsey Mark IV or Nissen fundoplication around the gastric tube, with placement of the repair in the abdomen.
Indications for performing an antireflux procedure by transthoracic approach are a previous antireflux procedure, esophageal myotomy for achalasia or diffuse spasm, esophageal stricture or Barrett's esophagus, hiatal hernia that does not reduce below the diaphragm, associated pulmonary pathology, and an obese patient (Fig. 23-5).
FIGURE 23-5 Algorithm of decision making for tailored antireflux surgery.
Studies have shown that the Nissen fundoplication is an effective and durable antireflux repair in 91 percent of patients over 10 years. Laparoscopic Nissen fundoplication has been shown to relieve typical symptoms of gastroesophageal reflux in greater than 90 percent of patients. Overall, there is a 4.2 percent conversion rate to open surgery and a 0.5 percent rate of early reoperation. The incidence of dysphagia has decreased to 35 percent with increasing experience and attention to technical details. Patients with early, uncomplicated gastroesophageal reflux are the best candidates for a laparoscopic approach. It is recommended that the surgical approach to patients with gastroesophageal reflux disease be selective, i.e., that the specific antireflux procedure for any patient be based on the patient's existing esophageal function.
The condition whereby the tubular esophagus is lined with columnar epithelium rather than squamous epithelium is an acquired abnormality that occurs in 710 percent of patients with gastroesophageal reflux disease and represents the end stage of the natural history of this disease.
The definition of Barrett's esophagus has evolved considerably over the past decade. Traditionally, Barrett's esophagus was identified by the presence of columnar mucosa extending at least 3 cm into the esophagus. Now, the diagnosis is made given any length of endoscopically identifiable columnar mucosa that proves on biopsy to show intestinal metaplasia. The hallmark of intestinal metaplasia is the presence of intestinal goblet cells.
Barrett's esophagus is associated with profound mechanical deficiency of the LES and marked esophageal acid exposure. The typical complications in Barrett's esophagus include ulceration in the columnar-lined segment, stricture formation, and a dysplasia-cancer sequence. It has the propensity to bleed, penetrate, or perforate. Risk of adenocarcinoma is variously estimated at 1 in 50 patient-years to 1 in 400 patient-years, a risk 40 times that of the general population. About one-third of all patients with Barrett's present with malignancy.
Patients whose symptoms are readily controlled by medication are suitable for medical therapy (histamine H2 blockers and omeprazole). Healing of ulcers and stabilization of strictures are not readily achieved. Medical treatment does nothing to correct the underlying defective sphincter and does nothing to reduce the reflux of alkalized gastric juice or prevent aspiration. The symptomatic relief may allow tissue damage to progress unnoticed, so advancement of the disease continues to occur. For this reason, surgery may be appropriate earlier in the course of the disease.
Since Barrett's esophagus is a premalignant condition, there are strong theoretical grounds for reversing the underlying cause before malignancy develops by performing antireflux surgery. Regression of Barrett's epithelium after surgery has not been reported often. There is a growing body of evidence to attest to the ability of fundoplication to protect against dysplasia and invasive malignancy. When high-grade dysplasia is discovered at biopsy, an esophagectomy is recommended because 50 percent of such specimens will show early invasive carcinoma.
The development of a stricture while on acid suppression therapy in a patient with a mechanically defective sphincter represents a failure of medical therapy and is an indication for a surgical antireflux procedure. Before surgery, a malignant etiology of the stricture should be excluded and the stricture progressively dilated up to a No. 60 French bougie. Three factors become important in the management of these patients: (1) the response to dilatation, (2) an assessment of esophageal length by endoscopy or barium swallow, and (3) adequacy of esophageal contractility on motility studies.
If the amplitude of esophageal contractions and the length of the esophagus are adequate, total fundoplication can be performed. In a patient with adequate esophageal length in whom dysphagia persists or esophageal contractility is compromised, partial fundoplication should be done. If the esophagus is shortened by the disease process, a gastroplasty and partial fundoplication should be performed.
ATYPICAL REFLUX SYMPTOMS
Chronic respiratory symptoms such as chronic cough, recurrent pneumonia, episodes of nocturnal choking, waking up with gastric content in the mouth, or soilage of the bed pillow also may indicate the need for surgical therapy. The chest radiograph in patients suffering from gastroesophageal reflux often shows signs of pleural thickening, bronchiectasis, and chronic interstitial pulmonary fibrosis. If 24-h pH monitoring confirms the presence of increased esophageal acid exposure and manometry shows a mechanical defect of the LES and normal esophageal body motility, an antireflux procedure can be done with an expected good result.
Chest pain may be an atypical symptom of gastroesophageal reflux and is often confused with coronary artery disease. Fifty percent of patients in whom a cardiac etiology of the chest pain has been excluded will have increased esophageal acid exposure as a cause of the episode of pain. An antireflux procedure provides relief of the chest pain with greater constancy than will occur with medical therapy.
Dysphagia, regurgitation, and/or chest pain on eating can be related to the presence of a large paraesophageal hernia, intrathoracic stomach, or a small hiatal hernia with a narrow diaphragmatic hiatus. The surgical repair of the hernia usually includes an antireflux procedure because of the potential of destroying the competency of the cardia during the surgical dissection.
REOPERATION FOR FAILED ANTIREFLUX REPAIRS
Placement of the wrap around the stomach is the most frequent cause for failure after open procedures, whereas herniation of the repair into the chest is the most frequent cause of failure after a laparoscopic procedure. This is probably due, in both instances, to an unrecognized short esophagus. Partial or complete breakdown of the wrap or construction of a too tight or too long wrap occurs with both open and closed procedures. Ten percent of these patients had an antireflux procedure for a misdiagnosed underlying esophageal motor disorder.
The preferred surgical approach to a patient who has had a previously failed antireflux procedure is through a left thoracotomy with a peripheral circumferential incision in the diaphragm to provide for simultaneous exposure of the upper abdomen and safe dissection of the previous repair from both abdominal and thoracic sides of the diaphragm. When dysphagia is associated with poor motility and multiple previous repairs, esophageal resection and replacement should be considered.
MOTILITY DISORDERS OF THE PHARYNX AND ESOPHAGUS
Clinical Manifestations Dysphagia is the primary symptom of esophageal motor disorders. To apply surgical therapy to the problem of dysphagia, the surgeon needs to know the precise functional abnormality causing the symptom. This usually entails a complete esophageal motility evaluation in addition to contrast studies and endoscopy.
Disorders of the pharyngoesophageal phase of swallowing result from a discoordination of the neuromuscular events involved in chewing, initiation of swallowing, and propulsion of the material from the oropharynx into the cervical esophagus.
Pharyngoesophageal swallowing disorders usually result from cerebrovascular accidents, brain stem tumors, poliomyelitis, multiple sclerosis, Parkinson's disease, pseudobulbar palsy, peripheral neuropathy, or operative damage to the cranial nerves. Muscular diseases such as radiation-induced myopathy, dermatomyositis, myotonic dystrophy, and myasthenia gravis are less common causes. Extrinsic compression by thyromegaly, cervical lymphadenopathy, or hyperostosis of the cervical spine can cause pharyngoesophageal dysphagia.
Video- and cineradiography are currently the most objective tests to evaluate oropharyngeal bolus transport, pharyngeal compression, relaxation of the pharyngoesophageal segment, and the dynamics of airway protection during swallowing.
In patients with Zenker's diverticulum, it has been difficult to consistently demonstrate a motility abnormality. Perhaps the diverticulum develops as a consequence of the repetitive stress of bolus transport through a noncompliant muscle of the pharyngoesophageal segment. A cricopharyngeal bar is a result of a noncompliant pharyngoesophageal segment and can be improved by a cricopharyngeal myotomy.
Zenker's pharyngoesophageal diverticula have occurred in 0.1 percent of 20,000 routine barium examinations, classically in elderly white males, and they tend to enlarge progressively with time. Presenting symptoms include dysphagia associated with the spontaneous regurgitation of undigested, bland material, often interrupting eating or drinking. The dysphagia can be severe enough to cause debilitation and severe weight loss. Chronic aspiration and repetitive respiratory infection are common associated complaints. The diagnosis is established by a barium swallow. Endoscopy is potentially dangerous, owing to obstruction of the true esophageal lumen and the attendant risk of diverticular perforation.
The low morbidity and mortality of a cricopharyngeal and upper esophageal myotomy has encouraged a liberal approach toward its use for almost any problem in the oropharyngeal phase of swallowing. This attitude has resulted in an overall success rate of only 64 percent.
The myotomy can be performed under local or general anesthesia through an incision along the anterior border of the left sternocleidomastoid muscle. The pharynx and cervical esophagus are exposed by retracting the sternocleidomastoid muscle and carotid sheath laterally and the trachea and larynx medially. The diverticulum is carefully freed from the overlying areolar tissue to expose its neck just below the inferior pharyngeal constrictor and above the cricopharyngeus muscle. Placement of a nasogastric tube into the cricopharyngeal sphincter helps in localization of the structures. The myotomy is extended cephalad, dividing 12 cm of inferior constrictor muscle and caudally dividing the cricopharyngeal muscle and the cervical esophagus for a length of 45 cm.
If the diverticulum is present after a myotomy, it may be inverted to the prevertebral fascia using a permanent suture. If the diverticulum is excessively large, a diverticulectomy should be performed. Recurrence of a Zenker's diverticulum is seen late, presumably because of persistence of the underlying loss of compliance of the cervical esophagus when a myotomy is not performed.
MOTILITY DISORDERS OF THE ESOPHAGEAL BODY AND LOWER ESOPHAGEAL SPHINCTER
With standard esophageal manometry, specific primary esophageal motility disorders have been recognized. These include achalasia, diffuse esophageal spasm, the so-called nutcracker esophagus, and the hypertensive LES. Twenty-four-hour monitoring of esophageal motor activity has shown that there are significant differences in the classification of esophageal motor disorders when based on standard manometry or ambulatory monitoring.
The best known and understood primary disorder of the esophagus is achalasia, a primary disorder of the LES. Abnormal esophageal peristalsis develops as a result of the increased resistance provided by the nonrelaxing LES. Observations in patients with pseudoachalasia due to tumor, a tight stricture, or a too tight antireflux procedure indicate that dysfunction of the esophageal body can be caused by the increased outflow obstruction. That esophageal peristalsis can return in patients with classic achalasia following dilatation or myotomy provides further support for a primary disease of the LES.
The pathogenesis of achalasia is presumed to be a neurogenic degeneration. In patients with the disease, degenerative changes have been shown in the vagus nerve and in the ganglia in the Auerbach plexus of the esophagus itself. Degeneration results in hypertension of the LES, elevation of intraluminal esophageal pressure, and a subsequent loss of peristalsis in the body of the esophagus. As the disease progresses, the esophagus becomes massively dilated and tortuous.
DIFFUSE AND SEGMENTAL ESOPHAGEAL SPASM
This esophageal motor disorder is characterized clinically by substernal chest pain and/or dysphagia. Diffuse esophageal spasm is primarily a disease of the esophageal body and is a rare condition occurring about five times less frequently than achalasia.
Hypertrophy of the muscular layer of the esophageal wall and degeneration of the esophageal branches of the vagus nerve have been observed. The classic manometric finding is simultaneous and repetitive esophageal contractions of abnormally high amplitude or long duration. The esophagus retains a degree of peristaltic performance in excess of that seen in achalasia. The LES usually shows normal resting pressure and relaxation of deglutition. In patients with advanced disease, the tertiary contractions appear helical and are termed corkscrew esophagus.
The disorder termed nutcracker' or supersqueezer esophagus is the most frequent of the primary esophageal motility disorders. It is a manometric abnormality characterized by peristaltic esophageal contractions with peak amplitudes greater than 2 standard deviations above the normal values in individual laboratories. Esophageal myotomy is a therapeutic option for patients with dysphagia and diffuse esophageal spasm but is of questionable value in patients with chest pain thought secondary to nutcracker esophagus.
HYPERTENSIVE LOWER ESOPHAGEAL SPHINCTER
This disorder is characterized by an elevated basal pressure of the LES with normal relaxation and normal propulsion in the esophageal body. About half of these patients have associated motility disorders of the esophageal body, particularly hypertensive peristalsis and simultaneous contractions. Myotomy of the LES may be indicated in patients not responding to medical therapy or dilatation.
NONSPECIFIC ESOPHAGEAL MOTOR DISORDERS
Many patients complaining of dysphagia or chest pain of noncardiac origin demonstrate a number of contraction patterns on esophageal manometry that are clearly out of the normal range but do not meet the criteria of a primary esophageal motility disorder. Surgery plays no role in the treatment of these disorders unless there is an associated diverticulum. Progression from a nonspecific esophageal motility disorder to classic diffuse esophageal spasm has been demonstrated. Twenty-four-hour esophageal pH and motility monitoring has shown that an increased esophageal exposure to gastric juice is common in patients diagnosed as having a nonspecific esophageal motility disorder.
DIVERTICULA OF THE ESOPHAGEAL BODY
An esophageal diverticulum most commonly occurs with nonspecific motility disorders but can occur with all the primary motility disorders. The motility disorder is usually diagnosed before development of the diverticulum.
Epiphrenic diverticula arise from the terminal third of the thoracic esophagus. They are classically pulsion diverticula and have been associated with diffuse spasm, achalasia, or nonspecific motor abnormalities in the body of the esophagus.
When associated with esophageal motility disorders, esophageal myotomy from the distal extent of the diverticulum to the stomach is indicated; otherwise, one can expect a high incidence of suture-line rupture. When a large diverticulum is associated with a hiatal hernia, the diverticulum is excised, a myotomy is performed, and the hernia is repaired because of the high incidence of postoperative reflux when it is omitted.
Midesophageal or traction diverticula were noted frequently in patients who had mediastinal lymph node involvement with tuberculosis. It is now believed that some diverticula in the midesophagus also may be caused by motility abnormalities.
Most midesophageal diverticula are asymptomatic and may be ignored. Patients with symptoms of dysphagia, regurgitation, chest pain, or aspiration in whom a diverticulum is discovered should be investigated thoroughly for an esophageal motor abnormality and treated appropriately.
The indication for surgical intervention is the degree of symptomatic disability. If a motor abnormality is documented, a myotomy should be performed.
Long Esophageal Myotomy for Motor Disorders of the Esophageal Body A long esophageal myotomy is indicated for dysphagia caused by any motor disorder characterized by segmental or generalized simultaneous contractions when symptoms are not relieved by medical therapy. Such disorders include diffuse and segmental esophageal spasm, vigorous achalasia, and nonspecific motility disorders associated with a mid- or epiphrenic esophageal diverticulum. Twenty-four-hour ambulatory studies aid in the identification of patients who might benefit from a surgical myotomy. The symptom of chest pain alone is not an indication for a surgical procedure.
Most surgeons extend the myotomy distally across the LES to reduce outflow resistance. Consequently, some form of antireflux protection is needed to avoid gastroesophageal reflux if there has been extensive dissection of the cardia. A partial fundoplication will not add resistance to interfere with the ability of the myotomized esophagus to empty.
A myotomy is performed through all muscle layers extending distally over the stomach 12 cm below the gastroesophageal junction and proximal on the esophagus over the distance of the manometric abnormality. The muscle layer is dissected from the mucosa laterally for a distance of 1 cm. The gastric fundic flap is sutured to the margins of the myotomy over the distal 4 cm and replaced into the abdomen. This maintains separation of the muscle and acts as a partial fundoplication to prevent reflux.
If an epiphrenic diverticulum is present, it is excised by dividing the neck and closing the muscle. The myotomy is then performed on the opposite esophageal wall. If a midesophageal diverticulum is present, the myotomy is made so that it includes the muscle around the neck, and the diverticulum is inverted and suspended by attaching it to the paravertebral fascia of the thoracic vertebra.
Postoperative motility studies show that myotomy reduces the amplitude of esophageal contractions to near zero, eliminating both simultaneous and peristaltic waves. A delicate balance exists between success and failure of a long esophageal myotomy, and this emphasizes the importance of preoperative motility studies.
Myotomy of the Lower Esophageal Sphincter Secondary to reflux disease, achalasia is the most common functional disorder of the esophagus to require surgical intervention. Relief can be achieved by an uncontrolled instrumental rupture of the sphincter muscle or by a controlled surgical myotomy. Surgical myotomy is associated with low morbidity and gives better long-term results. In practice, most patients are dilated. An inherent risk of pneumatic dilatation is rupture of the esophagus (as high as 15 percent).
In performing a surgical myotomy of the LES, there are four important principles: (1) minimal dissection of the cardia, (2) adequate distal myotomy to reduce outflow resistance, (3) prevention of postoperative reflux, and (4) prevention of rehealing of the myotomy site.
A modified Heller myotomy is performed through all muscle layers, extending distally over the stomach to 12 cm below the junction and proximally on the esophagus for 45 cm. The cardia is reconstructed by suturing the gastric fundic flap to the margins of the myotomy to prevent rehealing of the myotomy site and to provide reflux protection in the area of the divided sphincter.
If simultaneous esophageal contractions are associated with the sphincter abnormality, the so-called vigorous achalasia and then the myotomy should extend over the distance of the motility abnormality, as mapped by the preoperative motility study. When an antireflux procedure is added to the myotomy, it should be a partial fundoplication. A 360-degree fundoplication is associated with progressive retention of swallowed food, regurgitation, and aspiration. It has been shown that video-assisted endosurgical myotomy can be accomplished safely either laparoscopically or thoracoscopically.
Esophageal Resection for End-Stage Motor Disorders of the Esophagus Patients with dysphagia and long-standing benign disease whose esophageal function has been destroyed by disease or multiple surgical procedures are best managed by esophagectomy. Weak contractions, failure of the distal esophageal sphincter to relax, and loss of the secondary peristaltic reflex signal end-stage motor disease.
CANCER OF THE ESOPHAGUS
Squamous carcinoma accounts for most esophageal carcinomas. Its incidence is highly variable, ranging from approximately 20 per 100,000 in the United States and Britain to 540 per 100,000 in the Guriev District of Kazakhstan. Environmental factors such as food additives (nitroso compounds) and deficiencies (zinc and molybdenum) have been suggested. In Western societies, smoking and alcohol consumption are strongly linked with squamous carcinoma.
Adenocarcinoma of the esophagus, once an unusual malignancy, is diagnosed with increasing frequency and accounts for over 50 percent of the esophageal cancer in some Western countries. The most important etiologic factor in the development of primary adenocarcinoma of the esophagus is a metaplastic columnar-lined, or Barrett's, esophagus, which occurs as a complication in approximately 10 percent of patients with gastroesophageal reflux disease. This risk is similar to the risk for developing cancer of the lung in a person with a 20 pack-year history of smoking. There is no reliable evidence that medical therapy or an antireflux procedure removes the risk of neoplastic transformation; malignancy in Barrett's esophagus is curable if detected at an early stage.
Clinical Manifestations Esophageal cancer is a disease of advancing age, with dysphagia and weight loss the most common symptoms. Extension of the primary tumor can cause stridor, coughing, choking, aspiration pneumonia, severe bleeding, or vocal cord paralysis. Systemic metastases may cause jaundice or bone pain.
Dysphagia usually presents late in the natural history of the disease, when more than 60 percent of the esophageal circumference is infiltrated with cancer. Thus the disease is usually far advanced at the time of diagnosis, and greater than 40 percent of patients will have evidence of distant metastases.
Staging (Table 23-1) The stage of the disease is determined by the depth of penetration of the primary tumor and the presence of lymph node and distant organ metastases. Classification is based on imaging techniques. Computed tomographic (CT) scans only confirm clinical findings when extensive disease is present. Magnetic resonance imaging (MRI) has so far not been shown to be superior. Preoperative staging shows only minor differences in long-term survival among various stages of the disease. Only metastasis to lymph nodes and tumor penetration of the esophageal wall have a significant and independent influence on prognosis.
TABLE 23-1 STAGING OF CANCER OF THE ESOPHAGUS AND CARDIA: MODIFIED WNM CRITERIA
Tumor size, cell type, degree of cellular differentiation, and location of the tumor within the esophagus have no effect on survival of early lesions. Resectable esophageal tumors, which meet the criteria of no wall penetration and/or less than four regional lymph node metastases, could be defined as potentially curable.
The important goal of clinical staging of esophageal carcinoma is to determine cure or palliation. Making the selection for cure or palliation identifies the mission of the operation. It emphasizes the use of durable reconstruction in patients operated on for cure and identifies patients for multimodal therapy if surgical cure is not possible.
Clinical Approach Patient Selection The selection of surgical therapy for patients with carcinoma of the esophagus depends on the anatomic stage of the disease, the swallowing capacity of the patient, and the location of the primary tumor (Fig. 23-6).
FIGURE 23-6 Algorithm for the evaluation of esophageal cancer patients to select the proper therapy: curative en bloc resection, palliative transhiatal resection, or nonsurgical palliation. (From: DeMeester TR, Esophageal carcinoma: Current controversies. Semin Surg Oncol 13:217, 1997, with permission.)
Primary malignant tumors of the cervical esophagus are more common in females and drain directly into the paratracheal and deep cervical or internal jugular lymph nodes with minimal flow in a longitudinal direction. Lesions not fixed to the spine, not invading major vessels, and not having fixed cervical lymph node metastases should be resected.
Low cervical lesions that reach the level of the thoracic inlet are usually unresectable because of early invasion of the great vessels and trachea. The length of the esophagus below the cricopharyngeus is insufficient to allow intubation or construction of a proximal anastomosis for a bypass procedure.
Tumors that arise within the middle or upper third of the thoracic esophagus lie too close to the trachea and aorta to allow an en bloc resection. Only tumors that have not penetrated through the esophageal wall and have not metastasized to the regional lymph nodes are potentially curable.
Tumors of the lower esophagus and cardia are usually adenocarcinomas. Squamous cell carcinoma of the lower esophagus, however, does occur. Both tumors are amenable to en bloc resection. The longitudinal lymph flow in the esophagus can result in skip areas with small foci of tumor above the primary lesion, underscoring the importance of a wide resection of esophageal tumors. A curative resection requires a cervical division of the esophagus and a greater than 50 percent proximal gastrectomy. This compromises the length of the stomach and esophagus remaining to reestablish gastrointestinal continuity and necessitates a colon interposition.
An en bloc resection for cure of carcinoma of the esophagus is unwise in patients older than 75 years because of the additional operative risk in face of a short life expectancy.
Physiologic Status Patients undergoing esophageal resection should have sufficient cardiopulmonary reserve to tolerate the operation. The forced expiratory volume in 1 s (FEV1) should be 2 L or more; an FEV1 of less than 1.25 L carries a 40 percent risk of death from respiratory insufficiency within 4 years. Echocardiography and thallium imaging provide accurate information on wall motion, ejection fraction, and myocardial blood flow. A resting ejection fraction of less than 40 percent is an ominous sign.
Clinical Staging Clinical factors that indicate an advanced stage of carcinoma are recurrent nerve paralysis, Horner syndrome, spinal pain, paralysis of the diaphragm, fistula formation, and malignant pleural effusion. Factors that make surgical cure unlikely include a tumor greater than 8 cm in length, abnormal axis of the esophagus on a barium radiograph, enlarged lymph nodes on CT, a weight loss of greater than 20 percent, and loss of appetite. Staging depends on the length of the tumor measured with endoscopy and the degree of wall penetration and lymph node metastasis seen with endoscopic ultrasound. Finding a small tumor should encourage an aggressive approach, and the smaller the tumor, the more aggressive the approach should be.
Intraoperative Staging Intraoperative staging is designed for intraoperative selection of favorable candidates for a curative en bloc resection. Patients with a tumor that penetrates through the esophageal wall or multiple or distant lymph node metastases have a poor survival.
Curative en bloc dissection is abandoned if intraoperative staging reveals an unresectable primary tumor, cavitary spread of the tumor, distant organ metastasis, extension of the tumor through the mediastinal pleura, multiple gross lymph node metastases, or microscopic evidence of lymph node involvement at the margins of the en bloc resection. If the tumor does not extend through the esophageal wall and there are fewer than six lymph nodes positive, the 5-year survival is 75 percent (Fig. 23-7).
FIGURE 23-7 Algorithm of intraoperative decision making for cancer of the lower esophagus and cardia.
Management of Patients Excluded from Curative Resection If the patient is physiologically fit, a simple esophageal resection and reconstruction with esophagogastrostomy offers the best palliation. If an obstructing tumor cannot be resected because of invasion of the trachea, aorta, or heart, or when the patient's general condition precludes an operative procedure, a number of techniques, including bouginage, intubation, laser ablation, and electrical coagulation, are available and can be used alone or in combination.
The nutritional status of the patient is of paramount importance for the outcome of an esophageal resection. A feeding jejunostomy tube provides the most reliable and safest method for nutritional support in patients who cannot consume an oral diet and have a functionally normal small bowel. The jejunostomy is performed as a separate procedure to allow for preoperative nutritional support. Otherwise, the jejunostomy tube is placed at the time of esophageal resection.
Cervical Esophageal Cancer Tumors treated with radiation therapy initially tend to recur locally as well as systemically. Patients who undergo surgical therapy have few local recurrences of the tumor provided total excision was possible, but they succumb to metastatic disease. Improvements in the techniques of immediate esophageal reconstruction have reduced the complications of the surgical treatment of this disease and have encouraged a more aggressive surgical approach. Palliation is better achieved in patients who underwent esophagectomy with immediate gastric pull-up than in those who underwent primary radiation therapy or chemotherapy.
A total laryngectomy in combination with esophagectomy is necessary, and simultaneous en bloc bilateral neck lymph node dissection is done, sparing the jugular veins on both sides.
The thoracic esophagus is removed by blunt dissection through cervical and upper abdominal incisions, and gastrointestinal continuity is reestablished by pulling the stomach up through the esophageal bed.
Tumors of the Thoracic Esophagus and Cardia A combined transthoracic and transhiatal approach is used to remove tumors in the middle or upper third of the thoracic esophagus because of their tendency to adhere to hilar structures. Gastrointestinal continuity is reestablished by pulling up the previously prepared stomach through the posterior mediastinum and anastomosing it to the esophagus in the neck.
To remove tumors in the lower third of the thoracic esophagus and cardia, an en bloc resection for cure or a transhiatal removal for palliation is preferred. The en bloc resection is done through three incisions: right posterolateral thoracotomy with en bloc dissection of the distal esophagus, mobilization of the esophagus, closure of the thoracotomy, and repositioning of the patient in the recumbent position; an upper midline abdominal incision and en bloc dissection of the stomach and associated lymph nodes; and a left neck incision, transhiatal removal of the previously en bloc dissected distal esophagus and mobilized proximal esophagus, and left colon interposition. If an incurable situation is identified, a palliative resection is performed in a manner similar to that described for tumors of the middle and upper thoracic esophagus. A standard left thoracotomy, or an Ivor Lewis approach, is not advocated because of the proven need to resect long lengths of the esophagus to eradicate submucosal spread, the higher morbidity of a thoracic anastomotic leak, and the high incidence of esophagitis secondary to reflux following an intrathoracic anastomosis. Some surgeons advocate that if the morbidity of the procedure is acceptable, aggressive surgical attempts at cure with an en bloc dissection are justified.
Primary treatment with radiation therapy does not produce results comparable with those obtained with surgery. Its use is restricted to patients who are not candidates for surgery. There is a reluctance to treat patients with advanced disease.
The proposal to use adjuvant chemotherapy in the treatment of esophageal cancer began when it became evident that most patients develop postoperative systemic metastases without local recurrence. Systemic chemotherapy may be helpful if the cells are sensitive to the agent. On the other hand, chemotherapy may be a hindrance because of its immunosuppressive properties. Randomized, prospective studies with squamous cell carcinoma have shown no survival benefit with preoperative chemotherapy over surgery alone. A complete response to chemotherapy occurred only in 6 percent of patients. With the exception of the potential to improve resectability of tumors located above the carina, the benefits of preoperative chemotherapy are questionable.
Preoperative combination chemoradiotherapy using cisplatin and 5-fluorouracil in combination with radiotherapy has been reported to be beneficial in both adenocarcinoma and squamous cell carcinoma of the esophagus. Of all the randomized, prospective studies, only one showed any survival benefit with preoperative chemoradiotherapy over surgery alone.
Current data support giving chemoradiotherapy as a matter of routine in a limited number of clinical settings including (1) preoperatively to reduce tumor size in a young person with surgically incurable squamous cell carcinoma above the carina and (2) chemotherapy as salvage therapy for recurrent systemic disease after surgical resection (Fig. 23-8).
FIGURE 23-8 Suggested global algorithm for the management of carcinoma of the esophagus.
Sarcomas and carcinosarcomas are rare neoplasms. They present with the symptom of dysphagia, which does not differ from the dysphagia associated with the more common epithelial carcinoma. A barium swallow usually shows a large polypoid intraluminal esophageal mass. The smooth polypoid nature of the lesion is distinctive enough to suggest the presence of a sarcoma rather than the more common ulcerating, stenosing carcinoma. Esophagoscopy commonly shows an intraluminal necrotic mass. Accurate diagnosis by endoscopic biopsy is difficult because of surface necrosis.
Polypoid sarcomas of the esophagus remain superficial to the muscularis propria and are less likely to metastasize to regional lymph nodes. Thus the presence of a large polypoid tumor should not deter the surgeon from resecting the lesion. Sarcomatous lesions of the esophagus can be divided into epidermoid carcinomas with spindle cell features such as carcinosarcoma or true sarcomas such as leiomyosarcoma, fibrosarcoma, and rhabdomyosarcoma.
Surgical resection is the treatment of choice, since radiation therapy has little success. Surgical resection is responsible for the majority of the reported 5-year survivals.
BENIGN TUMORS AND CYSTS OF THE ESOPHAGUS
Benign tumors and cysts of the esophagus are relatively uncommon and are divided into those within the muscular wall and those within the lumen of the esophagus. The intramural lesions are either solid tumors or cysts; the most common are leiomyomas. Fibromas, myomas, fibromyomas, and lipomyomas, lipomas, neurofibromas, hemangiomas, osteochondromas, granular cell myoblastomas, and glomus tumors are all quite rare.
Intraluminal lesions are polypoid or pedunculated growths that originate in the submucosa, develop into the lumen, and are covered with normal stratified squamous epithelium. These tumors have a rich vascular supply; myxoma, myxofibroma, fibroma, and fibrolipoma are examples. Pedunculated intraluminal tumors should be removed.
Leiomyomas constitute more than 50 percent of benign esophageal tumors. The average age at presentation is 38 years. Leiomyomas are twice as common in males than in females. Because they originate in smooth muscle, 90 percent are located in the lower two-thirds of the esophagus.
Typically, leiomyomas are oval and remain intramural, and the overlying mucosa is freely movable and normal in appearance. Dysphagia and pain are the most common complaints. Bleeding related to the tumor is so rare that when hematemesis or melena occurs in a patient with an esophageal leiomyoma, other causes should be investigated.
A barium swallow is the most useful method to demonstrate a leiomyoma of the esophagus. The tumor appears as a smooth, semilunar or crescent-shaped filling defect, sharply demarcated, and covered and surrounded by normal mucosa. The mass should not be biopsied because of an increased chance of mucosal perforation at the time of surgical enucleation.
Leiomyomas should be removed surgically; the majority can be removed by simple enucleation. Large lesions or those involving the gastroesophageal junction may require esophageal resection.
Cysts may be congenital or acquired. Congenital cysts are lined wholly or partly by columnar ciliated epithelium of the respiratory type, by glandular epithelium of the gastric type, by squamous epithelium, or by transitional epithelium. Acquired retention cysts also do occur, probably from obstruction of the excretory ducts of the esophageal glands.
Enteric and bronchogenic cysts are the most common and arise as a result of developmental abnormalities during the formation and differentiation of the lower respiratory tract, esophagus, and stomach from the foregut.
Cysts vary in size and are usually located intramurally in the middle of the lower third of the esophagus. Their symptoms are similar to those of a leiomyoma. Surgical excision is the preferred treatment, with most able to be enucleated without damage to the mucosa.
Perforation of the esophagus constitutes a true emergency. It most commonly occurs following diagnostic or therapeutic procedures. Spontaneous perforation, referred to as Boerhaave's syndrome, is the etiologic cause for only 15 percent of such patients, foreign bodies for 14 percent, and other trauma 10 percent. Pain is a striking and consistent symptom. If subcutaneous emphysema is present, the diagnosis is almost certain.
Spontaneous rupture of the esophagus has a poor survival because of the delay in recognition and treatment. Air or an effusion in the pleural space shown on the chest radiograph is often misdiagnosed as a pneumothorax or pancreatitis. If the chest radiograph is normal, the diagnosis is often confused with a myocardial infarction or dissecting aneurysm.
Spontaneous rupture usually occurs in the left pleural cavity or just above the gastroesophageal junction. During vomiting, high peaks of intragastric pressure can be recorded, frequently exceeding 200 mmHg. When this pressure exceeds 150 mmHg, rupture of the esophagus is apt to occur. When a hiatal hernia is present and the sphincter remains exposed to abdominal pressure, the lesion produced is usually a Mallory-Weiss mucosal tear, and bleeding rather than perforation is the problem.
Diagnosis Abnormalities on the chest radiograph can be variable and should not be depended on to make the diagnosis. The presence of mediastinal emphysema, a strong indicator of perforation, takes at least 1 h to be demonstrated, and mediastinal widening secondary to edema may not occur for several hours. In cervical perforation, cervical emphysema is common and mediastinal emphysema rare; the converse is true for thoracic perforations. A pleural effusion secondary to inflammation of the mediastinum occurs late.
The diagnosis is confirmed with a contrast esophagram; water-soluble Gastrograffin is preferred. There is a 10 percent false-negative rate. When the patient is upright, the passage of water-soluble contrast material can be too rapid to demonstrate a small perforation. The studies should be done with the patient in the right lateral decubitus position to fill the whole length of the esophagus, allowing the actual site of perforation to be shown.
Management The key to optimal management is early diagnosis. The most favorable outcome is obtained following primary closure of the perforation within 24 h, resulting in 8092 percent survival. The most common location for the injury is the left lateral wall of the esophagus just above the gastroesophageal junction. The edges of the injury are trimmed and closed. The closure is reinforced with the use of a pleural patch or construction of a Nissen fundoplication.
After 24 h, survival decreases to less than 50 percent. If the delay approaches 24 h and the tissues are inflamed, division of the cardia and resection of the diseased portion of the esophagus are recommended. The remainder of the esophagus is mobilized, and as much normal esophagus as possible is saved and is brought out as an end-cervical esophagostomy. The contaminated mediastinum is drained, and a feeding jejunostomy tube is inserted. The recovery from sepsis is often immediate, dramatic, and reflected by a marked change in the patient's course in 24 h.
Nonoperative management of the esophageal perforation has been advocated in selected patients. Conservative management should not be used in patients who have free perforations into the pleural space. Cameron proposed three criteria for the nonoperative management of esophageal perforation: the barium swallow must show the perforation to be contained and drain well back into the esophagus, mild symptoms should be present, and there should be minimal evidence of clinical sepsis.
Accidental caustic injuries occur mainly in children. In adults and teenagers, the swallowing of caustic liquids is usually deliberate during suicide attempts.
Pathology Caustic substances cause both an acute and chronic injury. Alkalies dissolve tissue and, therefore, penetrate more deeply; acids cause a coagulative necrosis that limits their penetration. There is a correlation between the depth of lesion and the concentration of sodium hydroxide solution. Esophageal contractions are weakest at the striatedsmooth muscle interface. Clearance from this area may be somewhat slower, so caustic substances are in contact longer with the mucosa and affect this level more than in the lower portions.
The lesions caused by lye injury occur in three phases. In the acute necrotic phase, lasting 14 days after injury, there is a coagulation and an intense inflammatory reaction. In the ulceration and granulation phase, starting 35 days after injury, the superficial necrotic tissue sloughs, leaving an ulcerated, acutely inflamed base, and granulation tissue fills the defect. Third is the phase of cicatrization and scarring, which begins the third week following injury. The previously formed connective tissue begins to contract, resulting in narrowing of the esophagus. During this period, efforts must be made to reduce stricture formation.
Clinical Manifestations The clinical picture of an esophageal burn is determined by the degree and extent of the lesion. Early complaints consist of pain in the mouth and substernal region, hypersalivation, pain on swallowing, and dysphagia. Fever and bleeding can occur, and frequently the patient vomits. During the scarring phase, the complaint of dysphagia reappears and is due to fibrosis and narrowing of the esophagus. If dysphagia does not develop within 8 months, it is unlikely that a stricture will occur.
Early esophagoscopy is advocated to establish the presence of an esophageal injury. The scope should not be introduced beyond the proximal esophageal lesion in order to lessen the possibility of perforation. Radiographic examination is important in later follow-up to identify strictures.
Treatment The immediate treatment consists of limiting the burn by swallowing neutralizing agents within the first hour. Lye or other alkali can be neutralized with half-strength vinegar, lemon juice, or orange juice. Acid can be neutralized with milk, egg white, or antacids. Emetics are contraindicated because vomiting renews the contact of the caustic substance with the esophagus and can contribute to perforation if vomiting is too forceful. Hypovolemia is corrected, and broad-spectrum antibiotics are administered to lessen the inflammatory reaction and prevent infectious complications. A feeding jejunostomy tube is inserted to provide nutrition. Oral feeding can be started when the dysphagia of the initial phase has regressed. Dilatations can be started the first day after the injury with the aim of preserving the esophageal lumen. This approach is controversial in that dilatations can traumatize the esophagus. The use of steroids to limit fibrosis is debatable.
The presence of extensive necrosis of the esophagus frequently leads to perforation and is best managed by resection. When there is extensive gastric involvement, the esophagus is nearly always necrotic or severely burned, and total gastrectomy and near-total esophagectomy are necessary.
Some authors have advocated the use of an intraluminal esophageal stent in patients who are found to have evidence of esophagogastric necrosis; a biopsy of the posterior gastric wall should be performed to exclude occult injury. Esophagoscopy should be done if strictures are present, and dilatation should be initiated. Antegrade and retrograde dilatations with a Tucker bougie have been satisfactory. The length of time the surgeon should persist with dilatation before consideration of esophageal resection is problematic. If during the course of treatment an adequate lumen cannot be established or maintained, operative intervention should be considered.
Currently, the stomach, jejunum, and colon are the organs used to replace the esophagus, either through the posterior mediastinum or the retrosternal route. Free jejunal grafts based on the superior thyroid artery have provided excellent results. Minor errors of judgment or technique may lead to serious or even fatal complications.
The site of the upper anastomosis depends on the extent of the pharyngeal and cervical esophageal damage encountered. Recovery is long and may require several endoscopic dilatations and often reoperations. Sleeve resections of short strictures are not successful because the anastomosis is carried out in a diseased area.
The management of a bypassed damaged esophagus after injury is problematic. If the esophagus is left in place, ulceration from gastroesophageal reflux or the development of carcinoma must be considered. However, the extensive dissection necessary to remove the esophagus has a significant morbidity. Leaving the esophagus in place preserves the function of the vagus nerves and, in turn, the function of the stomach. Most experienced surgeons recommend that the esophagus be removed unless the operative risk is unduly high.
With the advent of clinical radiography, it became evident that a diaphragmatic hernia was a relatively common abnormality and was not always accompanied by symptoms. Three types of esophageal hiatal hernias were identified: the sliding hernia, the paraesophageal hernia, and the combined or mixed hernia. The end stage of a hernia occurs when the whole stomach migrates up into the chest by rotating 180 degrees, with the cardia and pylorus as fixed points. In this situation, the abnormality is usually referred to as an intrathoracic stomach.
Incidence and Etiology The true incidence of a hiatal hernia in the overall population is difficult to determine. Sliding hiatal hernia is seven times more frequent than a paraesophageal hernia. Structural deterioration of the phrenicoesophageal membrane over time may explain the higher incidence of hiatal hernias in the older age group. The phrenicoesophageal membrane yields to stretching in the cranial direction due to the persistent intraabdominal pressure and the tug of esophageal shortening on swallowing. The persistent posterior fixation of the cardia to the preaortic fascia and the median arcuate ligament is the only essential difference between a sliding and paraesophageal hernia.
Clinical Manifestations The clinical presentation of a paraesophageal hiatal hernia differs from that of a sliding hernia. There is usually a higher prevalence of symptoms of dysphagia and postprandial fullness with paraesophageal hernias, but the typical symptoms of heartburn and regurgitation are dominant in sliding hiatal hernia. Both are caused by an underlying mechanical deficiency of the cardia.
About one-third of patients with a paraesophageal hernia complain of hematemesis due to the recurrent bleeding from ulceration of the gastric mucosa in the herniated portion of the stomach. Respiratory complications are frequently associated with a paraesophageal hernia and may consist of recurrent pneumonia from aspiration. With time, the stomach migrates into the chest and can cause intermittent obstruction due to the rotation. The presence of a paraesophageal hernia can be life-threatening and lead to excessive bleeding or volvulus with acute gastric obstruction or infarction.
The symptoms of sliding hiatal hernias are usually due to functional abnormalities associated with gastroesophageal reflux and include heartburn, regurgitation, and dysphagia. These patients have a mechanically defective LES.
There are a group of patients with sliding hiatal hernias not associated with reflux disease who have dysphagia due to an obstruction of the swallowed bolus by diaphragmatic impingement on the herniated stomach. These patients usually have a mechanically competent sphincter, but the impingement of the diaphragm on the stomach can result in propelling the contents of the supradiaphragmatic stomach into the esophagus and pharynx, resulting in pharyngeal regurgitation and aspiration. This abnormality is confused with typical gastroesophageal reflux disease. Surgical reduction of the hernia results in relief.
Diagnosis A radiograph of the chest with the patient in the upright position can diagnose a hiatal hernia if it shows an air-fluid level behind the cardiac shadow. The paraesophageal hiatal hernia is a permanent herniation of the stomach; a barium swallow provides the diagnosis in virtually every case.
Fiberoptic esophagoscopy is very useful in the diagnosis and classification of a hiatal hernia because of the ability to retroflex the scope. A sliding hiatal hernia can be identified by noting a gastric pouch lined with rugal folds extending above the impression caused by the crura of the diaphragm. A paraesophageal hernia is identified on retroversion of the scope by noting a separate orifice adjacent to the gastroesophageal junction into which gastric rugal folds ascend.
Pathophysiology It has been assumed that a sliding hernia is associated with an incompetent distal esophageal sphincter, whereas a paraesophageal hiatal hernia constitutes a pure anatomic entity and is not associated with an incompetent cardia. Accordingly, surgical therapy has been directed toward restoration of the physiology of the cardia in patients with a sliding hernia and simply reducing the stomach into the abdominal cavity and closing the crura for a paraesophageal hernia.
Physiologic testing with 24-h esophageal pH monitoring has shown that paraesophageal hiatal hernia can be associated with pathologic gastroesophageal reflux. Physiologic studies have shown that the competency of the cardia depends on an interrelationship of distal esophageal sphincter pressure, its length exposed to the positive-pressure environment of the abdomen, and its overall length. A deficiency in any one of these manometric characteristics of the sphincter is associated with incompetency of the cardia regardless of whether the hernia is present. Patients with a paraesophageal hernia who have incompetent cardias have been shown to have a distal esophageal sphincter with normal pressure but a shortened overall sphincter length and its displacement outside the positive-pressure environment of the abdomen.
Therapy In a sliding hernia, even though the sphincter appears to be within the chest on a radiographic barium study, it still can be exposed to abdominal pressure because of the surrounding hernia sac that functions as an extension of the abdominal cavity. A high insertion of the phrenicoesophageal membrane into the esophagus gives adequate length of the distal esophageal sphincter exposed to abdominal pressure. A low insertion gives inadequate length.
In summary, the cause for a mechanical incompetency of the cardia is similar regardless of the type of hernia and is identical in patients who have an incompetent cardia and no hiatal hernia. The presence of a paraesophageal hiatal hernia is an indication for surgical repair. The life-threatening complications of bleeding, infarction, and perforation recommend surgical correction even in the elderly with a shorter life expectancy. Patients with a paraesophageal hernia treated medically may die from the complications of strangulation, perforation, and exsanguinating hemorrhage secondary to acute dilatation of the herniated intrathoracic stomach without warning. Patients with a paraesophageal hernia should have elective repair of their hernia regardless of the severity of their symptoms or the size of the hernia. If surgery is delayed and repair is done on an emergency basis, there is a 19 percent operative mortality, compared with less than 1 percent for an elective repair.
Based on pathophysiologic studies, the repair of a paraesophageal hernia should include an antireflux procedure. This is particularly necessary when the operation is performed on an urgent basis without preoperative studies.
MISCELLANEOUS ESOPHAGEAL LESIONS
This uncommon clinical syndrome is characterized by dysphagia associated with atrophic oral mucosa, spoon-shaped fingers with brittle nails, and chronic anemia. It characteristically occurs in middle-aged edentulous women. Iron-deficiency anemia is a common finding. Not all patients exhibit the classic syndrome, some lacking anemia, dysphagia, and an esophageal web.
Videoradiographic study and endoscopy have demonstrated a fibrous web just below the cricopharyngeus muscle as the cause of dysphagia. Treatment consists of dilatation of the web and iron therapy to correct the nutritional deficiency.
Clinical observation suggests that the esophageal web may be a drug-induced lesion. Since these patients have an iron-deficient anemia, it would be logical for physicians to prescribe ferrous sulfate, a drug known to cause esophageal injury. Malignant lesions of the oral mucosa, hypopharynx, and esophagus have been noted to occur in up to 10 percent of patients when followed long term.
Schatzki's ring is a thin submucosal circumferential ring in the lower esophagus at the squamocolumnar junction, often associated with a hiatal hernia. Its significance and pathogenesis are unclear. Various explanations of its origin have been put forward: It is a pleat of mucosa formed by infolding of redundant esophageal mucosa due to shortening of the esophagus; it is congenital; or it is an early stricture resulting from inflammation of the esophageal mucosa caused by chronic reflux.
Schatzki's ring is a distinct clinical entity having different symptoms. Twenty-four-hour esophageal pH monitoring showed that patients with a Schatzki's ring have a lower incidence of reflux than hiatal hernia controls. They also have better LES function.
Clinical symptoms associated with Schatzki's ring are episodes of short-lasting dysphagia during hurried ingestion of solid foods. Its treatment has varied from dilatation alone, dilatation with antireflux measures, an antireflux procedure alone, incision, and even excision of the ring.
Symptoms in patients with a ring are caused more by the presence of the ring than by gastroesophageal reflux. Furthermore, most patients with a ring but without proven reflux respond to one dilatation, whereas most patients with proven reflux require repeated dilatation. The majority of Schatzki's ring patients without proven reflux have a history of ingestion of drugs known to be damaging to the esophageal mucosa.
Schatzki's ring is probably an acquired lesion that can lead to stenosis from chemical-induced injury by pill lodgment in the distal esophagus or by reflux-induced injury to the lower esophageal mucosa.
The best form of treatment of a symptomatic Schatzki's ring in patients who do not have reflux consists of esophageal dilatation for relief of the obstructive symptoms. In patients with a ring who have proven reflux and a mechanically defective sphincter, an antireflux procedure is necessary to obtain relief and avoid repeated dilatation.
This syndrome is characterized by acute upper gastrointestinal bleeding following repeated vomiting. The mechanism is similar to spontaneous esophageal perforation, i.e., an acute increase in intraabdominal pressure against a closed glottis in a patient with a hiatal hernia.
Mallory-Weiss tears are characterized by arterial bleeding that may be massive. The diagnosis requires a high index of suspicion in the patient who develops upper gastrointestinal bleeding following prolonged vomiting or retching. Endoscopy confirms the suspicion by identifying one or more longitudinal fissures in the mucosa of the herniated stomach.
In the majority of patients the bleeding will stop spontaneously with nonoperative management. Only occasionally will surgery be required to stop blood loss. The procedure consists of laparotomy and high gastrostomy with oversewing of the linear tear.
Scleroderma is a systemic disease wherein esophageal abnormalities occur in approximately 80 percent of patients. Small-vessel inflammation appears to be an initiating event, with subsequent perivascular deposition of normal collagen that may lead to vascular compromise. In the gastrointestinal tract, the predominant feature is smooth muscle atrophy. Whether the atrophy in the esophageal musculature is a primary effect or occurs secondary to the neurogenic disorder is unknown. The results of pharmacologic and hormonal manipulation suggest that scleroderma is a primary neurogenic disorder. In advanced disease, manifested by smooth muscle atrophy and collagen deposition, poor esophageal pump and a poor valve result.
The diagnosis of scleroderma can be made manometrically by the observation of normal peristalsis in the proximal striated esophagus with absent peristalsis in the distal smooth muscle portion. The LES pressure is progressively weakened as the disease advances. Gastroesophageal reflux commonly occurs in patients with scleroderma because they have both hypotensive sphincters and poor esophageal clearance. This can lead to severe esophagitis and stricture formation.
Collis gastroplasty in combination with a Belsey antireflux repair is the usual surgical procedure for this problem. Surgery reduces esophageal acid exposure, but poor clearance of the esophagus persists. Consequently, only 50 percent of the patients have a good to excellent result. If the esophagitis is severe or there has been a previous failed antireflux procedure and the disease is associated with delayed gastric emptying, a gastric resection with Roux-en-Y esophagojejunostomy provides the best option.
The esophagus lies in immediate contact with the membranous portion of the trachea and left bronchus, predisposing to the formation of fistulas to these structures. Most acquired esophageal fistulas communicate with the tracheobronchial tree and are secondary to esophageal or pulmonary malignancy. Clinically, these fistulas are characterized by paroxysmal coughing following the ingestion of liquids followed by recurrent or chronic pulmonary infections.
Spontaneous closure is rare owing to the presence of malignancy or a recurrent infectious process. Surgical treatment of benign fistulas consists of division of the fistulous tract, resection of irreversibly damaged lung tissue, and closure of the esophageal defect. To prevent recurrence, a pleural flap should be interposed. Treatment of malignant fistulas is difficult and can be done best by using a specially designed esophageal endoprosthesis that bridges and occludes the fistula, allowing the patient to eat.
TECHNIQUES OF ESOPHAGEAL RECONSTRUCTION
Options for esophageal substitution include gastric advancement, colon interposition, and either jejunal free transfer or advancement into the chest. Rarely, combinations of these grafts will be the only possible option. The indications for esophageal resection and substitution include malignant and end-stage benign disease. The latter includes reflux or drug-induced stricture formation that cannot be dilated without damage to the esophagus, a dilated and tortuous esophagus secondary to severe motility disorders, lye strictures, and multiple previous antireflux procedures.
Partial Esophageal Resection Low-lying benign lesions, with preserved proximal esophageal function, are best treated with interposition of a segment of proximal jejunum into the chest and primary anastomosis. Because the anastomosis is within the chest, a thoracotomy is necessary.
The jejunum is a dynamic graft and contributes to bolus transport, whereas the stomach and colon function more as a conduit. Replacement of the cervical portion of the esophagus while preserving the distal portion is occasionally indicated in cervical esophageal or head and neck malignancy and following the ingestion of lye. Free transfer of a portion of jejunum to the neck has become a viable option and is successful most of the time.
Reconstruction Following Total Esophagectomy No pretense should be made that the intrathoracic stomach or colon functions as well as the native esophagus after an esophagogastrectomy. The choice between these organs will be influenced by several factors, such as the adequacy of their blood supply and the length of resected esophagus that they are capable of bridging. If the stomach is involved with pathology, the length available for esophageal replacement may not be adequate. Diverticular disease, unrecognized carcinoma, or colitis prohibits the use of the colon. The blood supply of the colon is more affected by vascular disease than the stomach and may prevent its use. The colon provides the longest graft. The stomach usually can reach to the neck if the amount of lesser curve resected does not interfere with the blood supply to the fundus. Gastric interposition has the advantage that only one anastomosis is required. There is greater potential for aspiration of gastric juice or structuring of the cervical anastomosis from chronic reflux when stomach is used for replacement.
Patients following esophagogastrectomy may have discomfort during or shortly after eating, resulting from the loss of the gastric reservoir. These symptoms are less common when the colon is used as an esophageal substitute, probably because the distal third of the stomach is retained in the abdomen, and interposed colon provides an additional reservoir function.
Dysphagia after reestablishing gastrointestinal continuity with the stomach following esophagogastrectomy is reported to occur in 50 percent of patients, two-thirds of whom require postoperative dilatation. By contrast, dysphagia is uncommon and the need for dilatation is rare following colon interposition. The high incidence of dysphagia with use of the stomach is probably related to the esophagogastric anastomosis in the neck and the difficulty this imposes to passage of the swallowed bolus.
Another consequence of the transposition of the stomach into the chest is the development of postoperative duodenogastric reflux. Adding a pyloroplasty may worsen this problem. Following gastric advancement, the pylorus lies at the level of the esophageal hiatus, and a distinct pressure differential develops between the intrathoracic gastric and intraabdominal duodenal lumens. Unless the pyloric valve is extremely efficient, the pressure differential will encourage reflux of duodenal contents into the stomach. Duodenogastric reflux is less likely to occur following colonic interposition because there is sufficient intraabdominal colon to be compressed by the abdominal pressure, and the pylorus and duodenum remain in their normal intraabdominal position.
Although there is general acceptance of the concept that the esophagogastric anastomosis in the neck results in less postoperative esophagitis and stricture than one at the lower level, reflux esophagitis following cervical anastomosis does occur, albeit at a slower rate than when the anastomosis is at a lower level. Most patients undergo cervical esophagogastrostomy for malignancy; thus the long-term sequelae of an esophagogastric anastomosis in the neck is not of concern. Patients who have had a cervical esophagogastrostomy for benign disease, however, may develop problems associated with the anastomosis in the fourth or fifth postoperative year, severe enough to require anastomotic revision. This is less likely in patients who have had a colon interposition for esophageal replacement. Consequently, in patients who have a benign process or a potentially curable carcinoma of the esophagus or cardia, a colon interposition is used to obviate the late problems associated with a cervical esophagogastrostomy. Colon interposition for esophageal substitution is a more complex procedure than gastric advancement, with the potential for greater perioperative morbidity, particularly in inexperienced hands.
Composite Reconstruction Occasionally, a combination of colon, jejunum, and stomach is the only reconstructive option available. This situation may arise because of previous gastric or colonic resection, recurrence of dysphagia after a previous esophageal resection, or following postoperative complications such as ischemia of an esophageal substitute. Although not ideal, combinations of colon, jejunum, and stomach used to restore gastrointestinal continuity function surprisingly well. This recognition may allow alimentary reconstruction in an otherwise impossible situation.
For a more detailed discussion, see Peters JH, DeMeester TR: Esophagus and Diaphragmatic Hernia, chap. 23, in Principles of Surgery, 7th ed.
Copyright © 1998 McGraw-Hill
Seymour I. Schwartz
Principles of Surgery Companion Handbook