The Free Jejunum Flap
The jejunum flap
Small bowel with a root of mesentery, lymphatics and vascular inflow.
Innervation: this flap is not innervated but it retains peristalsis and must be placed antegrade if tubed to prevent peristaltic reflux.
Blood supply: Branches from the supererior mesenteric artery and accompanying vein.
Artery: A large caliber artery at least 3 millimeters in size depending on the level of harvest of jejunal branches.
Vein: The corresponding veins are large, comparable or larger in size than the arter.
Pedicle length: Can be dissected up to 18 or 20 centimeters in length.
vascular Anatomy
The vascular antomy of the jejunum
The small bowel is supplied by the superior mesenteric artery (SMA). The bowel is held by the mesentery, the base of which travels from the left upper quadrant at the ligament of Treitz to the righly lower quadrant and the terminal ileum. The SMA distributes more than 10 major branches to the small bowel. The second or third branch provide adequate pedicle length and legnth of jejunum to supply the flap.
Operative Procedure
Bowel prep is performed the night before surgery. The patient is prepped supine, exposing and draping the abdomen. An upper midline incision, from below the xiphoid to just above the umbilicus is used for exposure.
An upper midline incision is used for exposure
The transverse colon and stomach are retracted superiorly, isolating the small bowel.The ligament of Trietz defines the apex of the small bowel mesentery. The jejunum is traced distally from this point and the branches from the superior mesenteric artery are identified. The second or third branch to the jejunum provides a long arterial pedicle and can perfuse the territory between adjacent segments nicely. For puroses of clairty the figure below shows a larger incision and the patient's head is to the left.
The flap is exposed and the mesenteric arterial and venous branches are isolated
The mesentery on either side of the vascular segment is divided, ligating small branches. When the bowel segment is defined, it can be divided and primary anastomosis of the remaining jejunum is done with suture or staples, depending on surgeon’s preference.
The flap is isolated
If a reconstruction is being peformed that requires a larger proximal lumen (like the hypopharynx) the antimesenteric border can be slightly incised to fishmouth the proximal flap. Alternatively, if the flap is being used as a mucosal lining, and not a tube, then the entire antimesenteric border can be longitudinally divided, providing a large mucosal flap.
for a mucosal non-tubed reconstruction the ENTIRE anti-mesenteric border can be incised to construct a mucosal sheet
Postoperative Care
Nasogastric suction is used as needed and feeding is begun when ileus has resolved and bowel function resumes.