Esophageal Reconstruction





Surgical Anatomy


Reconstruction of the esophagus requires a detailed knowledge of the anatomy of the esophagus itself as well as the conduits used:




  • Esophagus




    • The left side of the neck is preferred for reconstruction for three reasons:




      • The esophagus takes a slight bend toward the left in the neck.



      • The recurrent nerve, when aberrant, usually occurs on the right.



      • The recurrent nerve lies slightly farther away from the esophagus on the right side and therefore is less likely to be encircled when dissecting the esophagus from the left.




    • A cervical (as opposed to an intrathoracic) anastomosis is preferred for two reasons:




      • There is less reflux into the proximal esophageal segment.



      • Cervical anastomotic leaks are less life-threatening.




    • Reconstruction to areas proximal to or involving the cricopharyngeus (i.e., the pharynx) will undoubtedly affect the pharyngeal phase of swallowing, often necessitating the need for intense speech and swallowing therapy postoperatively.




  • Stomach




    • Is the most commonly used conduit.



    • Blood supply is based on the right gastroepiploic artery.



    • The fundus of the stomach is what reaches to the neck.




  • Colon




    • Is the second most commonly used conduit.



    • Is called a left colon graft because it is based on the ascending branch of the left colic artery, a branch of the inferior mesenteric artery.



    • Actual colon transposed is the transverse colon, along with portions of the right.







Preoperative Considerations



Indications for Esophageal Reconstruction





  • After resection for benign disease




    • Chronic acid reflux, multiple failed antireflux operations



    • Traumatic or iatrogenic injury



    • End-stage motility disorders (e.g., sigmoid esophagus)



    • End-stage connective tissue disorders (e.g., scleroderma)



    • Undilatable stricturing from chemical (e.g., lye ingestion), infectious, or drug-induced injury



    • Others




  • After resection for malignant disease




Choice of Conduit





  • Stomach




    • Simplest, requires only one anastomosis



    • Usually reaches to the cervical esophagus without difficulty but may have trouble reaching more proximally (i.e., pharynx)



    • Might not be usable because of extensive resection or injury to the pedicle (e.g., from G-tube placement)



    • Usually functions well early, as opposed to the colon, which may require an extensive “break-in” period



    • When placed in the substernal tunnel may have trouble reaching to the neck or demonstrate significant reflux and regurgitation




  • Colon




    • More complicated surgery, requires three anastomoses (interposed colon to proximal esophagus or pharynx; colon to stomach or small bowel; and colon to colon to complete gastrointestinal continuity)



    • Good size match



    • Durable blood supply



    • Usually requires a “break-in” period but functions well long-term



    • Can reach farther than the stomach to the most proximal portions of the pharynx



    • Does well in the substernal tunnel



    • Used when the stomach is unavailable as first choice





Route





  • Posterior mediastinal route preferred (more physiologic, less length required)



  • Substernal tunnel should be used in cases of delayed reconstruction (e.g., because of extensive scarring due to previous esophagectomy)



  • Location of anastomoses




    • Proximal and distal “targets” depend on underlying disease and extent of resection



    • Proximal




      • Most commonly the conduit (“neoesophagus”) is anastomosed to the cervical esophagus.



      • Anastomosis to the pharynx or piriform sinus may be necessary when extensive scarring of the esophagus and cricopharyngeus is present (e.g., lye ingestion). Anastomosis to the intrathoracic esophagus may be necessary when the patient has had previous extensive neck surgery or radiation.



      • Operative surgeon should perform his or her own endoscopy preoperatively to “map out” the exact location to maximize function and remove all disease (e.g., Barrett, strictures).




    • Distal




      • When stomach is used, not an issue



      • When the colon is interposed, usually the distal colon conduit is anastomosed to the antrum of the stomach (leaving additional stomach is not necessary and may actually cause extensive stasis long term).



      • Roux-en-Y loop of the small bowel is preferred when the stomach has been resected in its entirety.






Useful Preoperative Studies





  • Endoscopy




    • Esophagoscopy should be performed by the operative surgeon, preferably before any planned operation, but can be performed at the time of surgery if uncomplicated reconstruction is anticipated.




  • Video esophagogram




    • Gives information about both function and structure



    • Conventional barium swallow gives less information concerning function.




  • Mesenteric angiogram




    • Not always necessary but useful if compromised blood flow to conduit is suspected due to previous surgery or underlying disease (e.g., peripheral vascular disease, previous aneurysm repair)




  • Physiologic evaluation




    • History and physical examination



    • Renal, hepatic, nutritional, and hematologic laboratory assessment



    • Echocardiogram or stress test (if cardiac disease is suspected)



    • Pulmonary function tests (if pulmonary disease suspected)



    • Consider the integrity of the pharyngeal phase of swallowing (reconstruction of the esophagus would be of questionable benefit in a patient unable to swallow because of, e.g., irreversible stroke, neuromuscular disorder)







Operative Steps



Access to the Esophagus in the Neck





  • The neck should be prepped from the anterior chest to the earlobe.



  • The patient’s head should be slightly turned to the right and slightly extended to expose the sternocleidomastoid muscle.



  • An incision is made along the anterior border of the muscle and carried through the platysma.



  • The strap muscles (sternothyroid and sternohyoid) are divided close to the clavicle-sternum.



  • The plane between the carotid sheath (retracted laterally) and the trachea-larynx (retracted medially) is developed and the tracheoesophageal groove identified.



  • Dissection should proceed posteriorly to the anterior cervical fascia; just anterior to this the muscular fibers of the tubular esophagus can be identified.



  • The esophagus is then carefully dissected and encircled, making sure that the recurrent laryngeal nerve is protected.




Stomach as Conduit





  • The abdominal incision should be carried quite superiorly with resection of the xiphoid process.



  • Lap packs should be placed gently behind the spleen to move it forward.



  • A self-retaining retractor should be placed to retract the abdominal incision apart as well as under the left rib cage to retract it upward and outward to expose the undersurface of the left hemidiaphragm.



  • The lesser sac should be entered between the transverse colon and the greater curvature of the stomach, well away from the right gastroepiploic artery, approximately midline (not too close to the spleen and not too close to the duodenum, i.e., where it is “easy”).



  • The gastrocolic ligament should be divided away from the greater curvature, protecting the vascular pedicle, moving toward the left side, approaching the spleen and its short gastric arteries.



  • The short gastrics should be divided as close to the spleen as possible.



  • The gastrohepatic ligament should then be divided toward the right side, beginning where it was originally entered (i.e., where it was “easy”).



  • As the stomach is freed in this direction, both the right gastroepiploic artery and vein can be identified and followed proximally.



  • A Kocher maneuver is performed to allow additional length to the gastric graft.



  • As the most superior attachments to the spleen are divided, the lap packs behind the spleen are removed, thereby allowing the spleen to fall away and facilitate this portion of the dissection ( Fig. 29-1 ).




    Figure 29-1



  • The left crural attachments are divided and the mediastinum accessed.



  • Division of the central portion of the diaphragm directly superior to the esophagus allows better access to the mediastinum if esophageal resection is performed at the same time as reconstruction.



  • As the dissection proceeds from left to right, the gastrohepatic ligament, as well as the right crus, is identified.



  • The gastrohepatic ligament is divided, preserving the right gastric artery.



  • If there is an aberrant left hepatic branch coursing from the celiac axis, this vessel should be preserved if possible.



  • The left gastric artery is ligated.



  • The esophagogastric junction should be divided if not already done, usually through serial firings of a GIA stapler along the lesser curve ( Fig. 29-2 ).


Mar 13, 2019 | Posted by in CARDIOLOGY | Comments Off on Esophageal Reconstruction
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