General Thoracic Surgery (General Thoracic Surgery (Shields)) [2 VOLUME SET]

Editors: Shields, Thomas W.; LoCicero, Joseph; Ponn, Ronald B.; Rusch, Valerie W.

Title: General Thoracic Surgery, 6th Edition

Copyright 2005 Lippincott Williams & Wilkins

> Table of Contents > Volume II > The Esophagus > Section XXI - Operative Procedures in the Management of Esophageal Disease > Chapter 133 - Replacement of the Esophagus with Colon

Chapter 133

Replacement of the Esophagus with Colon

Ronald H. R. Belsey

INDICATIONS

The use of colon for esophageal replacement is indicated when long-term survival of the patient can confidently be expected: in cases of type IB (long gap) and type II congenital atresia; after resection of benign strictures or tumors; for advanced functional disorders; after numerous previous failed antireflux procedures; and in certain cases of malignant obstruction with an apparently good prognosis after radical surgery. The right or left colon is available for replacement. Left colon is preferable to right for the following reasons: its smaller diameter, the more constant and reliable blood supply from the left colic artery, its adequate length for total esophageal replacement, and its better ability to propel a solid bolus.

Right colon can be used when left colon is debarred by intrinsic disease or previous surgery. Incorporation of terminal ileum in the transplant has been advocated, but inclusion of the ileocecal valve may hinder progression of the swallowed bolus. Ventemiglia and colleagues (1977) investigated preoperative angiography and found a marginal artery in only 6 (30%) of 20 studies on the right colon but in all 20 (100%) of the left colons studied. By autopsy injection studies, Nicks (1967) demonstrated frequent anomalies in the venous drainage from the right colon that might jeopardize the survival of the transplant.

Why use colon? The frequently used alternative organ is the stomach, entire or tubed. The advantages of the stomach as an esophageal substitute are its reliable blood supply and the simple technique, involving a single anastomosis. Disadvantages include high morbidity from anastomotic failures, a tendency to dilatation and defective propulsion, and frequent late complications such as recurrent esophagitis and stenosis, gastric ulceration, and hemorrhage.

The observed advantages of colon, especially left colon, are the fewer lethal anastomotic problems (leaks can heal spontaneously), the progressive improvement in propulsive functional capacity, and its suitability for use in children. These advantages outweigh the disadvantages of the more complicated operative technique, which involves three anastomoses.

Contraindications to colon interposition consist of the following:

• Intrinsic colonic pathology. In practice, mild degrees of diverticulosis with no previous history of infection have not proved to be a significant contraindication.

• Mesenteric endarteritis. The endarteritis is commonly associated with systemic hypertension. Routine preoperative angiography is not recommended. The condition of the left colic artery and the vascular supply to the left colon can be assessed more accurately at operation.

• Subnormal colonic motility. In 15% of cases, colonic propulsive motility is subnormal. Preoperative detection of this defect currently is difficult. The history of bowel activity may be significant. Radiologic evidence of the rapidity or frequency of bowel evacuation is not a reliable guide. When perfected, motility studies of colonic function may provide essential information.

Jejunal interposition can be used for limited replacements, but variations in the vascular anatomy frequently debar it from extensive reconstructions.

In planning the reconstruction, the following features must be observed:

• An isoperistaltic interposition is mandatory.

• Protection of the vascular pedicle from mechanical obstruction by torsion, kinking, or tension is vital to the success of the technique.

• Three routes for the reconstruction are available: mediastinal, transpleural, and retrosternal. The menace to the integrity of the pedicle is least in the more direct mediastinal route and greatest in the more tortuous retrosternal route.

• A cologastric anastomosis incorporating an antireflux principle is essential to prevent peptic colitis.

• The tailoring of the transplant should prevent any intrathoracic redundancy, which can lead to mechanical obstruction by kinking. Moderate redundancy of the intraabdominal segment of the transplant is well tolerated.

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• The preferred anastomotic technique involves a single inverting layer of interrupted sutures of monofilament stainless steel wire or other nonirritating material. The advantages of wire are the complete lack of tissue reaction and the insignificant size and the security of the knots.

PREOPERATIVE PREPARATION

The general measures necessary in the preparation of a patient for major thoracic surgery are universally accepted and need not be repeated. Less generally recognized is the importance of eliminating all oronasal foci of infection. The mouth is probably the most heavily contaminated cavity in the body. Every esophageal resection incurs a risk of mediastinal infection. After the extraction of septic teeth, the gums should be allowed to heal before the operation. In the present context, the major concern is the preparation of the colon as a transplant for esophageal replacement. The aim is an empty, dry colon to reduce the risk of peritoneal, pleural, or mediastinal contamination during the interposition procedure. Time should be allowed for a full standard colon preparation in every case for which a resection and replacement might prove to be indicated at thoracotomy. The need for preoperative antibiotic therapy is debatable. Neomycin has caused severe enteritis because of changes in bowel flora. In my experience, no increase in peritoneal or pleural infection has been observed after the omission of preoperative antibiotic therapy.

OPERATIVE TECHNIQUE

Reconstruction with Left Colon

Exposure

The extended left sixth interspace thoracotomy incision, with division of the costal margin at the anterior limit of the sixth interspace, peripheral detachment of the diaphragm from its origin on the chest wall, and extension of the incision through the oblique muscles as far as the lateral margin of the rectus sheath, affords adequate exposure of the entire left hemithorax and the upper abdomen, with access to the organs available for reconstruction: the stomach, left colon, or jejunum. In those patients who have not had previous abdominal surgery, it may not be necessary to carry the incision across the costal margin. The spleen recedes beneath the posterior part of the diaphragm and is protected from injury.

Exploration

The position and extent of the esophageal lesion is determined by the preoperative studies. Exploration of the mediastinum is deferred until later in the procedure. The first step is the examination of the splenic flexure of the left colon: the adequacy of its preparation, the condition of the left colic and middle colic arteries by palpation of pulsation and compressibility, and the visible pulsation of the marginal artery and branches (Fig. 133-1). The marginal artery distal to its origin from the left colic artery, the main trunk of the middle colic artery, and the marginal artery to the right of the connections of the middle colic are all occluded temporarily by atraumatic vascular clamps to isolate the supply from the left colic vessels. Further inspection confirms the adequacy of the blood supply. The clamps are promptly removed.

Mobilization of the Left Colonic Transplant

This step is done before the mediastinum is explored. Postponing mediastinal dissection and mobilization of the esophagus prevents considerable blood loss from periesophageal vascular adhesions during the abdominal phase of the procedure. The greater omentum is detached from the colon from the splenic flexure to a point well to the right of the middle colic artery. The descending colon is mobilized by division of the peritoneal reflection along the lateral margin as far down as the junction of the descending with the sigmoid colon, where the colon is anchored to the posterior abdominal wall by a condensation of peritoneal tissue. With determined retraction of the abdominal wall, this band can be divided under direct vision. Mobilization of the splenic flexure and transverse colon, with its mesocolon, from the posterior abdominal wall necessitates division of the various ill-defined and irregular bands of vascular areolar tissue. The major vessels are contained in the mesocolon.

Isolation of the Blood Supply to the Transplant

After complete mobilization, the vascular anatomy of the left colon can be determined accurately. The continuity of the marginal artery in the region of the splenic flexure is confirmed. The mesocolon is divided above and below the left colic vessels. The division is extended to the right as far as the left branch of the middle colic artery, maintaining a 1- to 2-cm fringe of mesocolon to protect the marginal artery. The left colic artery, arising from the inferior mesenteric artery, usually supplies two branches to the marginal artery. The marginal artery is divided distal to or below both branches of the left colic. The division of the right-hand end of the marginal artery, or the left branch of the middle colic, is deferred until the esophagus is liberated from the mediastinum and the extent of the resection and length of transplant necessary for replacement are determined.

Pyloromyotomy

At this stage of the operation, a pyloromyotomy is performed. In the absence of a gastrostomy or abdominal wall adhesions resulting from previous gastric surgical intervention, the myotomy is performed on the anterior aspect of the

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Mobilization of the Esophagus

The preliminary intraabdominal maneuvers having been completed, attention can return to the mediastinum. Mobilization of the esophagus for the excision of benign lesions is easily achieved through the left thoracotomy incision. Most malignant lesions are equally accessible, except those directly involving the aortic arch. In the latter case, a right thoracotomy, combined with a separate laparotomy incision, may be preferable. The single-incision approach has obvious advantages. In the management of benign lesions by left colon replacement, only the diseased segment is excised, followed by an intrathoracic esophagocolic anastomosis. Subsequent anastomotic problems are less menacing and can be managed conservatively.

Many bypass procedures with colon usually call for a long segment of transplant capable of reaching the cervical esophagus, or even the pharynx in some cases. At this stage, the probable length of the transplant necessary for replacement or bypass can be estimated. An excessively long transplant can be tailored to a suitable length; if it is too short, tension on the anastomoses may promote complications.

Closure of the Cardia

The esophagogastric junction is divided. The stomach is repaired with two rows of inverting sutures. The cardia is not used for the subsequent cologastric anastomosis. The lower esophagus is ligated to prevent contamination of the mediastinum and pleura. If a bypass procedure is planned with the esophagus left in situ, the cardia is not divided, because it is important to maintain drainage of the lower segment between the stricture and the cardia to avoid creation of a closed loop of obstructed esophagus and the potential risk of a blowout.

Division of the Colon and Isolation of the Transplant

The point of division of the marginal artery and transverse colon at the proximal end of the planned transplant is selected. For a short-segment transplant, this point is just to the left of or distal to the point where the left branch of the middle colic joins the marginal artery. A single ligature is placed on the marginal artery, and the vessel is divided on the transplant side of the ligature. The divided vessel is allowed to bleed momentarily, affording the most graphic demonstration of the adequacy of the blood supply to the transplant from the left colic artery, a more reliable indication

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Preparation of the long-segment transplant for total replacement involves a different procedure. The marginal artery between the two branches of the middle colic artery is carefully examined and assessed. If the marginal artery is well developed and continuous, the left branch of the middle colic is divided near its origin from the main trunk of the middle colic, the intervening mesocolon is divided, and the marginal artery is ligated close to the point at which the right branch of the middle colic joins the marginal artery. Selection at this point results in a transplant long enough to reach the pharynx, if necessary, with retention of the right branch of the middle colic. The marginal artery is allowed to bleed momentarily, as noted in the previous paragraph, to confirm the adequacy of the blood supply. Rarely, the marginal artery between the two branches of the middle colic may be defective, or replaced by a plexus of vessels, the adequacy of which in terms of blood supply to the proximal end of the transplant may prove difficult to assess. In this situation, the two branches of the middle colic are retained to substitute for the defective margin. The main trunk of the middle colic is cleared and divided well proximal to the point of division into the two main branches. The continuity of the supply to the colon is maintained through the juncture of the two branches of the middle colic.

Any palpable residual colonic contents are milked from the segment destined for transplantation and into the descending colon below the level where it will be divided. The length of transplant having been determined, the colon is divided at the appropriate sites between two pairs of Pott's aortic clamps. The descending colon is divided below both branches of the left colic artery. The advantages of Pott's aortic clamps are the narrow blades and the minimal trauma they cause to the colonic tissue.

Colocolic Anastomosis

The continuity of the colon is restored by end-to-end anastomosis of the transverse colon to the descending colon. The divided ends of the bowel are approximated and held in this position by a seromuscular suture placed through the mesenteric border of the two segments. The Pott's clamps are removed and any residual fecal matter carefully mopped out of the now open bowel segments. Pledgets of Gelfoam may be inserted into the proximal transverse and descending colon to absorb any residual liquid fecal matter and reduce the risk of contamination during the anastomosis. These pledgets pass naturally when bowel function returns. Specimens are taken for culture as a guide to postoperative antibiotic therapy if necessary. The blood supply to the bowel segment is checked, especially for any evidence of venous engorgement, suggesting interference with the venous drainage caused by tension or rotation. An end-to-end, single-layer, inverting anastomosis is achieved by interrupted sutures of 5-0 or 6-0 monofilament stainless steel wire with the reef knots tied on the luminal side, commencing at the mesenteric border approximated by the initial suture, and working around each side alternatively until finally the anastomosis is completed by two or three sutures placed on the antimesenteric margins from the outside, with careful inversion of the colonic mucosa.

Cologastric Anastomosis

During the colocolic anastomosis, the transplant is wrapped in warm, moist gauze with the divided ends occluded by the clamps and with the vascular pedicle protected from tension or rotation.

The design of the cologastric anastomosis is an essential feature of the procedure and creates an effective antireflux mechanism to prevent peptic colitis. The anastomosis is performed on the posterior aspect of the stomach, near the greater curve, at a point one-third of the length of the fundopyloric distance distal to the fundus. An 8- to 12-cm segment of the transplant is retained in the infradiaphragmatic high-pressure region and creates an antireflux device similar in principle to the Mark IV antireflux operation for correction of an incompetent cardia; it is not necessary to perform any type of fundoplication around the intraabdominal colonic segment to achieve this objective. The lower posterior cologastric anastomosis also protects the vascular pedicle against tension or angulation. The low posterior anastomosis is advocated even when a retrosternal colonic bypass is performed.

The stomach is rotated on its long axis toward the right and maintained in this position by two traction sutures placed near the greater curve. The distal end of the transplant is approximated to the selected point by a seromuscular suture, and a transverse full-thickness incision is made into the lumen of the stomach between this point and the greater curve. The Pott's clamp is removed from the distal end of the transplant, and end-to-side cologastric anastomosis is performed using the technique previously described, with interrupted inverting sutures of monofilament stainless steel wire. Care is taken not to rotate the pedicle or the transplant. Hemostasis of the gastric incision is best achieved by closer spacing of the full-thickness anastomotic sutures rather than by cautery. Larger vessels may need ligation. After completion of the cologastric anastomosis, the stomach is allowed to fall back into its anatomic position, and the two stay sutures are removed.

Placement of the Transplant

Three routes for the transplant are available: (a) transhiatal and posterior mediastinal, after esophageal resection; (b) transhiatal and transpleural or through an additional opening in the diaphragm for a bypass procedure; and (c) retrosternal. The choice of route is influenced by one overriding consideration: the avoidance of tension, rotation, kinking, or other forms of mechanical obstruction of the

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Transhiatal and Posterior Mediastinal Route

The proximal end of the transplant is closed temporarily by a running suture, after removal of the Pott's clamp, to reduce soiling during placement of the transplant. A tunnel is created digitally through the lesser sac behind the fundus up to the hiatus. The cardia is already mobilized, and the peritoneal reflection and phrenicoesophageal membrane are divided during the resection of the esophagus and closure of the cardia. The end of the transplant is passed up through this tunnel, through the hiatus, and into the mediastinum without rotation. The pedicle lies medial to the transplant against the right pleura. Any venous engorgement of the transplant indicates rotation or kinking. If the hiatus is not available when a bypass procedure is planned, the left lobe of the liver is mobilized by division of the triangular ligament, and a separate opening is made in the central tendon of the diaphragm. A circle of tendinous tissue is excised to prevent contraction of the opening. The transplant is passed up behind the fundus and into the left pleural cavity.

If a long-segment interposition for total replacement is indicated, the esophageal resection has already vacated the mediastinal tunnel up to the apex of the thorax. The end of the transplant is threaded up deep to the aortic arch and anchored to the stump of the esophagus or the side of the mobilized esophagus near the apex of the thorax with two stout sutures. Sutures of different colors can be used to confirm the absence of rotation when the transplant is delivered into the neck. The cervical esophagus is mobilized as high as possible from within the thorax because of the greater ease of identifying the appropriate tissue planes.

Transpleural Route

The transpleural route is the second choice. If a colonic bypass procedure by the transpleural route is planned, a tunnel is established through the superior thoracic outlet to accommodate the transplant. The pleura and deep cervical fascia are incised transversely posterior to the inner ends of the first rib and clavicle. The internal mammary artery and vein can be divided. The lateral margin of the costoclavicular ligament is incised. The anterior jugular vein is gently dissected posteriorly by digital and blunt dissection until an adequate tunnel is created and the dissecting finger reaches the skin in the posterior triangle of the neck just above the clavicle and posterior to the sternocleidomastoid muscle. Two stout sutures loaded on large, curved cutting needles are passed through the end of the transplant, up through the tunnel created, and out through the skin of the neck. The end of the transplant is drawn up into the tunnel and approximated to the skin by the anesthetist, who then ties two sutures over a bridge of skin to retain the transplant until the cervical incision is made.

Retrosternal Route

This route pursues a more tortuous, and consequently more hazardous, course. The danger areas are the region of the xiphoid, where the transplant takes a right-angle bend upward; in the retrosternal tunnel, where rotation may inadvertently occur; and at the narrow superior thoracic outlet. The low posterior cologastric anastomosis previously described is advocated to avoid mechanical embarrassment of the pedicle at its origin if an anterior anastomosis is attempted. The transplant is passed through the lesser sac, behind the stomach, through the gastrohepatic omentum, to the xiphoid region. The retrosternal tunnel must be large enough to accommodate the transplant without compression. The anterior margin of the diaphragm is incised backward, or detached from its costal origin sufficiently to reduce the sharp angulation of the transplant around the anterior margin. The superior thoracic outlet at the upper limit of the tunnel must be dissected and enlarged under direct vision from the cervical incision to avoid any constriction at this point. A flat strip of metal, with two perforations at its lower end, is passed down through the tunnel. The closed end of the transplant is sutured to these perforations and drawn up through the tunnel. In this manner, rotation of the transplant in the tunnel can be avoided. It is never necessary to perform a median sternotomy to ensure correct placement of the transplant in the retrosternal tunnel. An infected sternotomy wound is one of the most dreaded of all postthoracotomy complications.

Once the transplant reaches the cervical incision, a critical inspection of the blood supply is essential. Any evidence of venous engorgement is a danger signal indicating mechanical interference with the vascular pedicle. The whole course of the transplant from its origin must be reviewed until the cause of the problem is determined and corrected by readjusting the lie of the transplant or by eliminating the offending anatomic factor. Obstruction of venous drainage can lead to loss of the transplant or to progressive fibrosis of the proximal end of the transplant and recurrent obstruction, leaks from the esophagocolic anastomosis and salivary fistulae, or strictures of this anastomosis. Complications at the esophagocolic anastomosis occur more commonly after the use of the retrosternal route.

Intrathoracic Esophagocolic Anastomosis

After resection of the lower esophagus, an end-to-end esophagocolic anastomosis is performed by the standard

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Prevention of Intrathoracic Colic Redundancy

Any redundant transplant must be excluded from the thorax, because kinking may result in obstruction, necessitating further surgery. On completion of the esophagocolic anastomosis, the transplant, which usually contracts during manipulation, is gently stretched manually to its normal length. Any redundant transplant is pulled gently downward into the abdominal cavity. The transplant is anchored to the margin of the hiatus by running or interrupted nonabsorbable seromuscular sutures around two-thirds of the circumference, avoiding the area of the vascular pedicle. Before closure, the management of the defect in the transverse mesocolon must be considered. Attempts to suture the defect result in several small defects, with an enhanced risk of small bowel obstruction and strangulation. Our practice is to leave the defect wide open, with the assumption that a large defect is less likely to lead to strangulation than multiple small defects. The greater omentum is wrapped around the colocolic anastomosis and plugged into the mesocolon defect to discourage small bowel herniation. The diaphragm is reattached to its costal origins, and the incision is closed with catheter drainage of the pleural cavity.

Cervical Esophagocolic Anastomosis

When a cervical anastomosis is planned, the colon is anchored to the margin of the hiatus without any tension on the intraabdominal portion of the vascular pedicle. Any intrathoracic redundancy can be corrected by gentle upward traction on the transplant at the time of the cervical anastomosis. Excess colon is trimmed back before the anastomosis. With the patient turned supine, an incision is made along the anterior border of the left sternocleidomastoid muscle. After division of the middle thyroid veins and the inferior thyroid artery, the thyroid gland is retracted medially and the carotid sheath is moved posteriorly.

If the cervical esophagus is freed adequately from within the thorax, it is simple to deliver the organ from the mediastinum with the closed proximal end of the transplant attached. The esophagus is trimmed back to the level just distal to the cricopharyngeal sphincter, which is preserved as a major structure for protecting the air passages against reflux and aspiration.

The closed end of the transplant is excised, and the blood supply is inspected for any evidence of venous engorgement or arterial ischemia. When first opened, the bleeding may appear to be mainly venous, suggesting some obstruction to the venous drainage. After allowing free hemorrhage for a few minutes, the bleeding becomes progressively more arterial, and the colonic mucosa pinks up and loses the cyanotic appearance, suggesting venous obstruction. Persistence of cyanosis and venous engorgement indicates a serious obstruction at a lower level and may call for reopening of the thoracotomy wound. It is an error of judgment to proceed with the anastomosis if any doubt remains about the adequacy of the colonic blood supply.

An end-to-end esophagocolic anastomosis is accomplished as for an intrathoracic anastomosis. The cervical incision is closed without drainage because it communicates freely with the left pleura and insertion of a drain may result in a persisting pneumothorax as well as increased risk of anastomosis leakage. Cervical tissue planes are adequately drained internally by the intercostal catheter.

Cervical Bypass Anastomosis

With the patient supine, an oblique incision is made along the anterior margin of the left sternocleidomastoid, or a transverse collar incision is made and the skin flaps are elevated. With the sternocleidomastoid retracted laterally, the proximal end of the transplant is located in the tunnel created from within the thorax behind the inner ends of the first rib and clavicle. After obtaining a firm grip on the transplant with Babcock forceps to prevent retraction back into the thorax, the transplant is liberated by dividing the sutures anchoring it to the skin of the posterior triangle. The transplant is drawn out of the thorax as far as possible with gentle traction and a constant watch on the blood supply, to eliminate any intrathoracic redundancy. Any excess length of the transplant is trimmed back as necessary. The cervical esophagus is exposed as previously described. A vertical incision is made in the lateral wall of the esophagus, and the edges are distracted by two stay sutures. The closed end of the transplant is excised and the blood supply is observed. The length of the esophagotomy incision is tailored to the diameter of the transplant. A side-to-end esophagocolic anastomosis is effected by the single-layer wire technique. The cervical incision is closed without drainage.

Retrosternal Route

If the retrosternal route was used, the cervical incision was made during the creation of the retrosternal tunnel. The proximal end of the transplant has already been placed through the tunnel into the cervical incision. To establish

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Reconstruction with Right Colon

Mobilization of the right colon requires a separate laparotomy incision. A right fifth or sixth interspace thoracotomy follows if an esophageal resection and replacement are planned. Alternatively, if a bypass procedure is intended, the retrosternal route can be developed from the laparotomy incision and an additional cervical incision. The first step is inspection of the vascular anatomy of the right colon, with confirmation of the presence of the normal middle colic artery and an adequate, well-developed marginal artery. A critical area is the ileocecal junction. It is common practice to include the terminal ileum and ileocecal valve in the transplant, but this is only feasible when the marginal artery is obviously continuous in this region and the blood supply is adequate. The possible disadvantages of including the ileocecal valve have been discussed under Indications.

The right colon and transverse colon are mobilized in a similar fashion to that already described for the left colon. The appendix is excised. The greater omentum is detached from the hepatic flexure and transverse colon to a point well to the left of the middle colic artery. The right colic and ileocecal arteries are sacrificed close to their origins from the superior mesenteric artery to maintain continuity of the marginal artery. The middle colic artery with both branches intact forms the vascular pedicle of the transplant. The vascular anatomy of the right colon is more variable than that of the left and may limit its use for esophageal substitution (see Fig. 133-1). The length of the necessary transplant having been determined, the colon segment is mobilized in a similar fashion to that described for the left colon. The marginal artery is divided to the left of both branches of the middle colic. After division of the transverse colon and the terminal ileum, an end-to-end ileocolic anastomosis is performed if no gross dissimilarity exists in the lumina of the two viscera. Alternatively, the divided end of the transverse colon can be closed and an end-to-side ileocolostomy performed. The same anastomotic technique is used as in the case of the left colon interposition.

The pedicle from the middle colic artery dictates an anterior cologastric anastomosis. Retention of a segment of transplant within the abdomen discourages reflux but is not as effective in preventing reflux as the posterior cologastric anastomosis.

If esophageal resection and replacement are indicated, the cardia is mobilized from the hiatus together with the lower one-third of the esophagus and then divided. The stomach is closed. The lower end of the esophagus is ligated. The closed end of the ileum is attached to the lower end of the esophagus with two stout sutures of different colors to diminish the risk of rotation. The laparotomy incision may be closed at this stage. Alternatively, with the patient positioned on the table in the oblique rather than a full left lateral position, the chest is opened through the anterior right fifth or sixth interspace and the esophagus is mobilized from the mediastinum. The synchronous exposure of thorax and abdomen permits inspection of the vascular pedicle as the transplant is transferred to the thoracic cavity and reduces the risk of inadvertent rotation. It is common practice for two surgical teams to work synchronously on the mobilization of the transplant and the esophageal resection. When the retrosternal route is preferred for a bypass procedure, the tunnel is developed from the laparotomy and an additional cervical incision. The precautions necessary to prevent mechanical interference with the pedicle are the same as in the routes previously described. In the event of a bypass, the cardia is left in continuity to maintain drainage of the lower esophageal segment below the obstructing lesion.

Both the intrathoracic and cervical anastomoses after resection are accomplished by the previously described technique. The esophagoileal anastomosis is facilitated by the correspondence in size of the two lumina. For a bypass procedure, the side-to-end esophagoileal anastomosis is advocated to maintain drainage of the segment of esophagus between the anastomosis and the stricture.

Reconstruction with colon, preferably left, after a transhiatal esophagectomy is accomplished in the same manner when performed through an extended left thoracotomy incision. The use of the flat metal strip to draw the proximal end of the transplant up to the cervical incision reduces the risk of rotation of the transplant or its pedicle and subsequent ischemic necrosis.

POSTOPERATIVE CARE

Management of the patient follows along the same lines as after any major thoracic operation. Oral alimentation is restored as soon as a barium esophagography indicates healing of the anastomoses. If the described anastomotic technique with monofilament wire is used, it is safe to start the patient on a liquid diet on the third postoperative day, progressing rapidly to soft solids. Ice cream is always acceptable to the patient after any major esophageal procedure.

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Postoperative Complications

Necrosis of Transplant

The common cause of necrosis of the transplant is technical mismanagement of the vascular pedicle caused by inadequate exposure; excessive handling of the transplant; prolonged use of vascular clamps; torsion, tension, or kinking of the pedicle during placement of the transplant; or an anterior colon gastric anastomosis. Other causes of necrosis are failure to observe mesenteric endarteritis, anomalies of the vascular anatomy, or signs of obstruction to the venous drainage.

Signs of transplant necrosis include septic toxemia, fetor, and regurgitation of foul-smelling secretions. Endoscopy confirms the diagnosis, but opaque swallows with radiography may fail to reveal the complication until ischemic dissolution of the transplant occurs. Once the diagnosis is confirmed, the transplant is excised, probably through the original incision. The stomach and esophageal stump are closed; a cervical esophagostomy is performed either a lateral esophagostomy if the intrathoracic remnant is to be retained or an end esophagostomy if the remainder of the esophagus is exteriorized and abandoned. A feeding gastrostomy or jejunostomy, depending on which organ will ultimately be used for subsequent reconstruction, is performed. Any further attempt at reconstruction is delayed for 3 to 6 months and probably consists of a cervical esophagogastrostomy.

Anastomotic Fistulae

The highest recorded incidence of leaks has been at the esophagocolic anastomosis. These leaks can be observed in postoperative esophagography in asymptomatic patients. These fistulae usually run a benign course and heal spontaneously, however, because of the nonerosive nature of the colonic secretion. Operative repair is seldom necessary. An important advantage of colon over gastric interposition is the lower morbidity associated with anastomotic problems.

Anastomotic Strictures

The incidence of strictures has largely been eliminated by the routine use of the anastomotic technique described in the text. The essential features of this technique are tissue apposition without tissue strangulation and the avoidance of excessive quantities of suture material.

Wound Infection

Wound infection is an uncommon complication in spite of the theoretic risks of contamination from encroachment of the lumina of both esophagus and colon.

Paracolic Hiatal Herniation

Herniation of small bowel through the hiatus alongside the colon transplant can only occur if a circumferential suture of the seromuscular layer of the transplant to the margins of the hiatus is omitted or incorrectly sited.

Herniation of Small Intestine through the Mesocolon

Herniation of small intestine through the mesocolon has largely been eliminated by the technique of inserting the greater omentum into the defect in the mesocolon before closure of the extended thoracotomy incision.

Progressive Fibrostenosis in the Proximal End of the Transplant

Progressive fibrostenosis in the proximal end of the transplant has been reported as a late complication. The probable explanation is a reaction to chronic venous engorgement related to mechanical embarrassment of the vascular pedicle. Management is by prevention. If the stenosis cannot be controlled adequately by repeated dilation when necessary, the esophagocolic anastomosis along with the stenotic segment of the transplant is excised, followed by reanastomosis.

Redundancy of the Transplant

A major complication is redundancy of the transplant within the thorax and intermittent obstruction caused by mechanical kinking. The complication is avoidable by intraoperative tailoring of the length of the transplant and by replacing any redundant transplant below the diaphragm after completion of the anastomosis and before anchoring the transplant to the margin of the hiatus. If upward prolapse occurs, resulting in kinking and obstruction of a redundant loop, the original incision is reopened and the loop is freed and returned to the abdomen. Redundant colon below the diaphragm is well tolerated and rarely causes obstructive symptoms.

Sluggish Colon

Another major long-term complication is a functionally inadequate transplant caused by the use of a segment of inherently sluggish colon for reconstruction. If reliable tests for assessing colonic function before surgery can be developed, the sluggish colon can be detected and rejected as an unsuitable organ for esophageal substitution and replaced by stomach or jejunum.

Gastrocolic Reflux and Peptic Colitis

Gastrocolic reflux and peptic colitis were described by Malcolm (1968). In all instances, the cologastric anastomosis

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POSTOPERATIVE MORTALITY

Postlethwait (1983) reviewed the published data on colonic interposition in 474 patients operated on between 1971 and 1981 in 12 different centers, indicating no extensive experience in any one group of surgeons. The operative mortality was 4.9%, the same as in my experience. The general consensus is that the operative mortality should be less than 5% in cases in which the interposition was performed for benign disease. The mortality probably approaches 10% in cases of malignant obstruction treated by this technique.

LONG-TERM FUNCTIONAL RESULTS

Benages (1981), Corazziari (1977), and Jones (1973) and associates investigated a small series of adult patients by pH and manometric studies after the technique of colon interposition just described. All three reports had similar conclusions:

• The resting pH in the colon transplant remains neutral, with no evidence of reflux.

• Rapid clearing by stimulated peristalsis is observed after the installation of 0.1 N hydrochloric acid.

• Peristaltic contractions occur spontaneously in approximately one-third of the patients studied and in response to an acid bolus in all patients.

The functional results tend to improve with the passage of time. When used for reconstruction in infants and children, the colon transplant has been observed to grow at the same rate as the child when he or she is followed into adult life. Anderson and colleagues (1992) reported satisfactory functional results in long-term follow-up studies in children with colonic substitution.

In another publication, Paris and associates (1991) reported on the functional results observed 3 to 16 years (mean of 11.4 years) after esophageal replacement with isoperistaltic segments of left colon for benign disease in 18 patients. Clinical results were excellent or good in 12 (71%) of 17 operative survivors. The single fatality resulted from liver failure. Manometric studies revealed transmission of esophageal waves through the esophagocolic anastomosis and a uniform colonic response with sequential peristaltic waves. The authors reported more rapid radionuclide transit after short-segment transplants than after more extensive interpositions. They conclude that a colon segment as esophageal substitute with reliable and peristaltic contraction takes an active part in the alimentary bolus transit. In my opinion, valuable lessons from this study are the delay necessary in postoperative functional studies to allow time for the transplanted viscus to develop its new responsibilities, and the value of long-term clinical follow-up.

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