Jejunum Tissue Transfer 

Updated: Oct 28, 2018
Author: Tamer A Ghanem, MD, PhD; Chief Editor: Arlen D Meyers, MD, MBA 

Overview

Background

Patients with cancer of the hypopharynx and cervical esophagus are faced with several daunting issues. First, they must face the fact that their disease carries an overall 5-year survival rate for stage II-IV disease of 24-39%.[1] Second, and perhaps equally important, they must become reconciled with the fact that they will lose their ability to swallow or speak normally. The hypopharynx is the most inferior portion of the pharynx. Its superior border begins at the tip of the epiglottis, and the inferior border incudes the lower level of the cricoid cartilage.

For most patients dealing with such a dire prognosis, the one thing that allows them to consider pharyngoesophageal resection is the knowledge that a reconstructive procedure can help to restore speech and swallowing functions. Depending on surgeon preference and postoperative hospital course, patients can be introduced to liquids and solids within 1 week of surgery.[2]

Because of the low survival rate and the likelihood of recurrence in advanced cases of pharyngoesophageal cancer, the method of reconstruction chosen should provide restoration of swallowing in one stage with minimal morbidity. Given that a significant amount of hyopharyngeal cancer resections result in circumferential defects, it is important for the reconstruction to provide adequate coverage with limited complications. Microvascular free flaps are increasingly being used for reconstruction of these complex defects. The jejunal flap, the tubed radial forearm flap, and the anterolateral thigh flap work well in these situations.[3]

Other methods commonly used for pharyngoesophageal reconstruction include colon interposition, gastric pull-up, or tubed pectoralis major myocutaneous flaps. Although all these techniques can provide a good pharyngoesophageal reconstruction, they are associated with higher rates of operative mortality (11-20%) and fistula formation (35-40%) than jejunum free tissue transfer.

History of the Procedure

The free jejunal flap is unique because it was the first free flap described in the literature. Seidenberg first published his case in 1959, and the technique was further refined by Serafin and Buncke in 1979.[4] Microvascular free jejunal reconstruction of the pharyngoesophagus has become increasingly reproducible and reliable. Currently, overall success of free jejunal flap for reconstruction ranges from 95-97%.[2, 5]

Indications

Jejunal free flap reconstruction is used in the reconstruction of the oral cavity, oropharyngeal, and primarily circumferential defects (see the image below) of the upper aerodigestive tract. However, the most common indication is reconstruction of circumferential pharyngeal defects after extirpative surgery for hypopharyngeal carcinoma.[6, 7]

Neck surgical wound showing a circumferential phar Neck surgical wound showing a circumferential pharyngeal defect from the base of tongue to the cervical esophagus.

Reconstruction using the jejunum provides a way to reestablish the mucosal conduit, thereby preserving the patient's ability to swallow. Speech, if lost as a result of resection of the larynx, is not as effectively restored. Patients commonly project a “wet voice.” Tube lengths of up to 30 cm can replace lost segments of the cervical esophagus from the nasopharynx to the thoracic inlet.[8]

The ablative procedure dictates the most appropriate reconstructive technique. Defects that extend into the chest are best reconstructed using techniques that do not place a suture line in the chest, which potentially results in mediastinitis should a leak occur. Typically, a gastric pull-up or colonic interposition is performed in these cases.

The large amount of normal secretions formed by the jejunum make its use in patients with an intact larynx suboptimal. These secretions lead to persistent aspiration if the jejunal free flap is not below a functioning cricopharyngeus. Other options such as the tubed radial forearm flap, scapular or parascapular flap, a combination of a pectoralis flap and a free flap, or anterolateral thigh flap can be used for the reconstruction without the problems associated with excess secretions.

Relevant Anatomy

The small bowel is composed of 3 distinct anatomic and physiologic segments: the duodenum, jejunum, and ileum. The jejunum begins at the ligament of Treitz and extends distally 6-8 feet. Its vascular supply is based off the superior mesenteric artery and vein; these vessels pass over the middle portion of the duodenum and enter the mesentery of the jejunum. Several jejunal arterial segmental branch off the superior mesenteric artery, and each communicates with an arcade that in turn communicates with the vasa recta. The vasa recta supply specific segments of the jejunum. This allows the surgeon to pick a segment of jejunum (usually 10-20 cm) and to trace the blood supply back to the jejunal segment feeding this jejunal segment.

As one moves distally in the small bowel, the number of vascular arcades increases in the ileum, and, therefore, indistinct perfusion patterns arise off of single arterial pedicles. Typically, the second jejunal branch is the pedicle of choice. When the dissection is carried right down to the superior mesenteric artery, arterial pedicles up to 3-4 mm in diameter and up to 20 cm in length can be obtained.

Contraindications

Previous small-bowel surgery (jejunal), uncontrolled ascites, chronic diseases of the jejunum, and documented mesenteric vascular disease specifically preclude the use of the jejunum.Patients who require upper aerodigestive tract reconstruction secondary to ablative cancer surgery often have much comorbidity. Most of the associated medical factors are not absolute contraindications to a lengthy surgery or, specifically, using a jejunal free flap. Medical risk factors that may complicate intra-abdominal and free flap surgery should be optimized preoperatively.

 

Workup

Imaging Studies

Direct imaging of the jejunum with endoscopy, barium swallow follow-through, or computerized tomography scanning is seldom performed.[9] Vascular studies of the superior mesenteric vessels are also not routinely performed. Postoperatively, imaging studies are used if there is clinical suspicion of patient or flap morbidity.

 

Treatment

Surgical Therapy

Patients undergoing free jejunal reconstruction are not usually given a bowel preparation before surgery. A bowel preparation is given the night before surgery only if concern exists over extensive adhesions and the possibility of an enterotomy.

Preoperative Details

Perioperative antibiotics as well as 81 mg of aspirin are routinely administered before surgery.

Intraoperative Details

One of the advantages of this flap is the ablative and reconstructive team are able to work simultaneously. Jejunal harvesting is performed by a general surgeon in conjunction with the microvascular reconstructive surgeon. Depending on the general surgeon's preference and expertise, harvesting can be via an open laparotomy approach or laparoscopically.

The following discussion focuses on the open laparotomy approach. An upper midline laparotomy is followed by identification of the ligament of Treitz. Transillumination of the mesentery helps the surgeon to select the segment of the jejunum that is to be harvested. A longer segment than is needed to reconstruct the defect is usually harvested. If a sentinel loop of jejunum is to be used for monitoring, this is factored into the length to be harvested (see the images below).[10] The distal end of the jejunum is marked so that the jejunum can be placed in an isoperistaltic orientation in the neck.

Transillumination showing the network of arches on Transillumination showing the network of arches on the mesenteric border of the jejunum.
The segment of jejunum to be harvested is outlined The segment of jejunum to be harvested is outlined. A small segment harvested adjacent to the main loop is used for monitoring purposes.

The artery supplying the segment of the jejunum to be harvested is located, and the mesentery is marked in a triangle. The vessels are dissected back to their branching point off the superior mesenteric artery. Care at this point in the dissection prevents troublesome bleeding at the root of the small bowel mesentery. The bowel is then divided using a GIA stapler (US Surgical Corp; Norwalk, CT). Small-bowel continuity is reestablished with a stapled jejunojejunostomy. The mesentery is closed, and a distal feeding jejunostomy tube is placed. The artery and vein supplying the divided segment are not separated until the neck vessels have been prepared for microvascular anastomosis.

Neck vessel preparation is simultaneously completed by a second surgical team. Because the jejunum tolerates ischemia poorly, preparation of the neck vessels is vital prior to separating the jejunum from its vascular supply. Typically, ischemic times should be less than 90 minutes; longer intervals can lead to permanent damage or loss of the jejunum.

In general, the enteric anastomoses are performed first. High proximal enteric anastomoses tend to be the most difficult. As such, they are carried out first in a 2-layered fashion with absorbable sutures. The serosa is attached to the prevertebral fascia so as to take tension off this proximal enteric anastomosis. An end-to-end distal enteric anastomosis is performed, placing the jejunal autograft in an isoperistaltic position and under a small amount of stretch. This prevents kinking of the jejunal segment in the neck, which can cause regurgitation of food and dysphagia. The microvascular anastomoses are then completed. If a sentinel loop of bowel has been designed, it is left free to be brought out through the skin incision as a postoperative monitor. This monitor loop is removed one week postoperatively (see the image below).

After wound closure, the monitoring segment can be After wound closure, the monitoring segment can be seen in the lateral aspect. It is dressed with Xeroform dressing to prevent gastric secretions from bathing the wound. It is taken down in 5-7 days postoperatively, at bedside.

Modifications of the enteric anastomoses are performed to allow the jejunum to fit the defect in the upper aerodigestive tract. Spatulation proximally allows the small-caliber jejunum to fit larger defects. Triangular interdigitation distally into the esophagus decreases the incidence of stricture formation. Excess mesentery may be used to reinforce the enteric anastomosis. In addition to hand-sewn anastomosis, a GI end-to-end anastomotic device maybe utilized to anastomose the jejunum to the upper esophagus. See the images below.

Jejunal free flap with pedicle and short monitorin Jejunal free flap with pedicle and short monitoring segment.
GI end-to-end anastomotic device used to couple th GI end-to-end anastomotic device used to couple the distal end of the jejunal flap to the proximal cervical esophagus.
This photo shows the completion of the pedicle ana This photo shows the completion of the pedicle anastomoses and the jejunal free flap anastomosis to the cervical esophagus and base of tongue. Jejunal monitoring segment is placed outside the wound.

Postoperative Details

Postoperatively, the patient is monitored overnight on the floor or in an intensive care step-down unit, depending on the institutional preference. No anticoagulation other than the preoperative aspirin is routinely administered. The sentinel loop is monitored for arterial and venous insufficiency and mucus production. This segment may be placed in a bowel bag to collect the secretion and prevent desiccation. Enteral feeding via the jejunostomy tube is begun immediately. Internal Doppler probes may also be used in conjunction to the bowel monitoring segment to monitor the arterial or veinous anastomosis.

A barium swallow is performed approximately 10 days to 2 weeks postoperatively. Normal findings on barium swallow do not guarantee sealed enteric anastomoses. Similarly, the presence of a leak observed radiologically does not always carry clinical significance. Clinical judgment must always be used prior to beginning oral feeding.

Complications

The goal of reconstruction is to restore functional status in the shortest period of time with the least morbidity. With the jejunal free flap, complications specific to the operation can occur in the donor area, the microvascular anastomosis, or at the enteric anastomoses. Each can compromise reconstructive efforts or the patient's life.

Abdominal complications, while infrequent, include bleeding and hematoma from the root of the mesentery of the jejunum. Care in dissection of the vascular pedicle to the segment of jejunum to be used is of prime importance. Individual identification and ligation of the vessels usually eliminates problems.

Internal hernia and small-bowel leaks are rare and can be kept to a minimum by closure of the mesentery and careful reestablishment of bowel continuity. Abdominal tenderness postoperatively can cause difficulties with patient mobility and pulmonary toilet.

Microvascular complications have significantly improved over the past 20 years. Overall failure rates have been reported to be 3-20%. A large review has reported an overall free flap success rate of 91% in 672 patients. Ischemia tolerance is notoriously poor with this flap, necessitating rapid vascular reanastomosis and detection of flap compromise when it occurs.

Fistula formation and stricture formation can occur with any reconstructive technique. The rate of fistula formation is reported at 18%. Of these, over two thirds close spontaneously. Use of the free jejunum has the advantage of a relatively low rate (ie, 10%) of stricture formation.

Outcome and Prognosis

The free jejunum flap has gained popularity as the success of the microvascular technique has increased. With flap survival and successful reconstruction rates as high as 97.6% and the patient mortality rate less than 5%, this technique has proven both effective and reliable.

Resumption of oral alimentation is observed in 60-90% of patients within 10-16 days postoperatively.

Future and Controversies

Although the free jejunum effectively reconstructs the lost portion of the upper aerodigestive tract with a mucosal lined conduit, many problems still exist. Current techniques of tracheal puncture provide acceptable speech, but one of the most significant problems with jejunal reconstruction is the "wet" and relatively poor quality of voice. As experience with microsurgical technique increases, morbidity from the operation may decrease, and functional outcomes will naturally improve.