The jejunum is an option for either partial or total esophageal replacement (Fig. 23-3). There are several advantages to consider with small bowel reconstruction. It generally remains free of intrinsic disease throughout a patient's life span and does not undergo senescent lengthening. Compared to the native esophagus, the size-match is excellent. There is a relative abundance of the organ, which permits reconstruction of the whole esophagus with adequate length to maintain nutritional demands. The jejunum also has a reliable blood supply with fairly consistent anatomy that does not routinely require preoperative evaluation. In the past, there were limitations on the length of esophagus that could be reconstructed with the jejunum, but this issue largely has been overcome with microvascular augmentation techniques that can accommodate grafts spanning from the base of the neck to the abdomen.
Jejunal grafts are preferred for malignant esophageal replacement in the three situations depicted here. A. Jejunal segment after distal esophageal resection. B. Jejunal replacement for esophagus and proximal or entire segment (Roux-en-Y). C. A free segment requiring microvascular vessel anastomosis interposed in the cervical region.
Jejunal interpositions can be tailored to any length necessary to replace the resected esophagus. We have found jejunal interpositions to be especially useful for secondary reconstruction attempts after a gastric conduit loss that has resulted in esophageal diversion. Conduit position is also determined in part by the indication requiring reconstruction. Most often placed in the retrosternal position, a supercharged jejunal conduit also may be placed in the posterior mediastinum or less often subcutaneously on the anterior chest. We believe the microvascular anastomosis and subsequent lie of the conduit are best when the conduit is in the substernal position. If local recurrence in the posterior mediastinum is a factor, or the need for radiation exists, the conduit should be placed away from this field.
Long-Segment Supercharged Jejunal Conduit
Routine preoperative evaluation is necessary when planning a supercharged jejunal conduit for esophageal replacement. A complete history and physical examination should be performed, and it is important to take note of any previous abdominal, thoracic, or sternal incisions as they may alter the surgical plan and position of the conduit. In the setting of esophageal cancer, complete staging should be performed, including esophagogastroduodenoscopy/endoscopic ultrasound (EGD/EUS) and PET/CT. A CT chest/abdomen with contrast will help rule out metastatic disease, along with abnormalities of the small bowel or major abdominal vessels. Consultation with a plastic surgeon in addition to the thoracic surgeon is necessary when planning a supercharged jejunal conduit. Thorough preoperative patient education and counseling focusing on postoperative expectations, including dietary and lifestyle modifications that will be necessary following the procedure should be provided. In contrast to a colon interposition, there is no need for presurgical preparation of the bowel. Naturally, if one is concerned about the viability of the small bowel as a useable conduit, it is not a bad idea to have the colon prepared as another alternative.
Surgical Procedure The patient is positioned supine with a shoulder roll in place and the head turned slightly to the right. The left neck, chest, and abdomen are prepped into the field. The legs may be prepped into the field at the discretion of the plastic surgeon for possible harvest of a saphenous vein graft.
Abdomen An upper midline incision is made and the ligament of Treitz identified along with the proximal jejunum. A complete lysis of adhesions should be performed and any prior feeding jejunostomy or gastrostomy should be taken down and the bowel repaired. Transillumination of the proximal jejunal mesentery will delineate the individual jejunal vessels and their arcades (Fig. 23-4). The first vessel off of the superior mesenteric artery is generally left in place for blood supply to the fourth portion of the duodenum and proximal jejunum. The conduit is then generally based on the second to fourth jejunal vessels, but this can vary depending on the available anatomy. No vessels are divided at the outset of the case. The mesentery is dissected to expose the vessels for the transfer. Attention is then turned toward the route through which the conduit will pass. The posterior mediastinal route will not be described in detail as it is standard procedure for most thoracic surgeons to place a gastric conduit in this location; we do not often place a supercharged jejunum in this location.
The technique of long-segment supercharged jejunal (SPJ) conduit is depicted here and in the next three illustrations. Shown here is the vascular anatomy of the proximal jejunum.
Neck A collar incision is made starting at the sternal notch and proceeding upward and lateral along the anterior border of the sternocleidomastoid muscle. Before fully exposing the esophagus, the left hemimanubrium, head of clavicle, and medial aspect of the first rib are removed to increase the space available in the thoracic inlet for the conduit and microvascular anastomosis to the left internal mammary artery. This also alleviates points of bony compression on the conduit which could lead to mesenteric congestion and vascular compromise. Care must be taken when freeing the inferior aspect of the clavicle and first rib so as to not injure the internal thoracic vessels.
The esophagus is exposed by retracting the sternocleidomastoid and carotid sheath laterally and the thyroid medially. Medial retraction should be performed with great care to avoid injury to the recurrent laryngeal nerve. If the patient already is in discontinuity, the esophagostomy should be taken down and the esophagus positioned in the neck where it will lie for the anastomosis. The end of the esophagostomy must generally be trimmed back to healthy mucosa for creation of the anastomosis.
Retrosternal Tunnel We usually create a retrosternal tunnel about four fingers wide for the conduit to pass through as it traverses the chest. A measuring device is used to determine the minimum distance required for the conduit to traverse the thoracic cavity, yet allow for a tension-free anastomosis in the neck. Great care should be used for this dissection so as not to compress the anterior cardiac wall which can cause cardiovascular embarrassment. This measurement is critical because it is used to determine the location of the distal aspect of the conduit. As much as is practically possible, the conduit should lie in a straight line with no redundancy or large mesenteric loops in the bowel. The position of the conduit is critical to forming a straight, well-functioning jejunal interposition.
Conduit Creation and Passage The proximal pedicle of the jejunum, usually the second jejunal vessel, is divided close to its origin from the superior mesenteric artery (Fig. 23-5). The bowel is divided a few centimeters proximal to this point. The next jejunal vascular pedicle, usually the third, is also divided close to its origin. The mesentery that lies between these two vessels is divided toward the mesenteric border of the bowel to allow the jejunum to unfurl and straighten (Fig. 23-6). This step is key to establish a straight course through the mediastinum and a more accurate estimate of the length needed.
The divided proximal pedicle.
For a jejunogastric anastomosis, the length is measured to the posterior wall of the stomach, and the distal aspect of the jejunum is divided at the appropriate length. For a Roux limb, the distal jejunum does not require division.
After measuring and dividing the bowel and mesentery, the conduit is passed behind the colon (retrocolic) for a posterior mediastinal reconstruction, or in front of the colon (antecolic) for a retrosternal reconstruction. The conduit is placed inside a plastic bag to allow safe passage through the mediastinum. The plastic bag provides protection for small vessels as the conduit is pulled through the chosen mediastinal route. One must ensure that no twisting of the conduit occurs as it is pulled through the mediastinum. Care also must be taken to avoid excess traction on the conduit as this can lead to tearing of the mesentery and result in ischemic areas. Once positioned in the neck, the recipient vessels are prepared and the vascular augmentation is performed. The venous anastomosis is typically performed to the internal jugular vein. Saphenous vein grafts can be used if there is a length discrepancy. The arterial anastomosis is then performed under the operating microscope. Usually the artery can be connected directly to the carotid; if there is a length issue it can be anastomosed to a branch vessel or a short Gore-tex graft can be used.
An “indicator flap” can be created with the distal most 2 or 3 cm of jejunum. The distal 2 to 3 cm of the jejunum and its intact mesentery is separated from the main conduit and set aside to be externalized at the completion of the procedure as an indicator flap (Fig. 23-7).
Reconstruction The esophagojejunal anastomosis is performed via a hand-sewn or stapled technique. A stapled functional end-to-end anastomosis may be performed with a posterior linear staple line between the esophagus and jejunal conduit followed by hand-sewn or TA closure of the “hood” (modified Collard or Orringer technique). Alternatively the circular EEA device may be used, but care must be taken to avoid a blind pouch that will lead to a pseudo-Zenker's phenomenon.
The abdominal reconstruction is performed either by creating a “Roux” limb and distal jejunojejunal anastomosis or via a jejunogastric anastomosis low on the posterior wall of the stomach. We generally create a Roux limb as more often there is no remaining stomach for reconstruction. If stomach is chosen we advocate a prior 2/3 gastrectomy to avoid gastric stasis issues created by a vagotomized stomach. A feeding jejunostomy is then performed. If there is remaining stomach that is not in continuity with the conduit (i.e., a Roux limb was created), a drainage procedure at the pylorus should be performed.
When closing the neck incision the indicator flap should be positioned at the inferior aspect of the wound in a straight course so as not to compromise the blood supply. Once a drain is placed and the wound closed, one or both ends of the indicator segment should be opened to allow for drainage of secretions. This flap is left externalized as a monitor for the perfusion of the proximal bowel segment until just prior to discharge. At that point, it can be amputated at the bedside.
Most of the complications seen after a supercharged jejunal conduit are similar to those seen after esophagectomy. Bowel ischemia resulting in conduit loss is infrequent. Thrombosis or diminished flow through the vascular anastomosis may occur and if perfusion is compromised, the vascular augmentation should be revised to avoid graft loss. The indicator flap serves as a guide to the viability of the conduit and should be monitored frequently. Suspicion of conduit ischemia should prompt evaluation.
Other complications such as bleeding, aspiration pneumonia, recurrent laryngeal nerve damage, redundant bowel loop, and stricture formation are managed using standard techniques.
Recently presented data update the 10-year experience from MD Anderson Cancer Center. Sixty patients received a supercharged jejunal conduit, largely for reconstruction related to esophageal cancer. Postoperative complications included 18 (30%) patients with pneumonia, 19 (31.7%) patients with an anastomotic leak (9 required major intervention, others were managed conservatively), and 4 (6.7%) patients with graft loss. The majority of patients (88%) were able to return to a regular diet after jejunal reconstruction. Thirty-day mortality, including in-hospital mortality, was 5% with a 90-day mortality of 10%. Median survival was 28 months, and the 5-year overall survival in this series is 30%. These results represent a group of high-risk patients, 42% of which were undergoing reversal of discontinuity. Given these results, we prefer a supercharged jejunal conduit for esophageal reconstruction only when the stomach is not available.