Infrarenal abdominal aortic aneurysms: transperitoneal video-assisted surgery

The description of the Infrarenal abdominal aortic aneurysms: transperitoneal video-assisted surgery covers all aspects of the surgical procedure used for the management of (description de la pathologie en cause). Operating room set up, position of patient and equipment, instruments used are thoroughly described. The technical key steps of the surgical procedure are presented in a step by step way: Introduction, Anatomy, Arterial network, Vein-nerve relationships, Operating room, Trocar placement, Instruments, Exposure, Dissection I, Dissection II, Clamping, Minilaparotomy, Opening the aneurysm, Graft implantation, Closure, Conclusion, Reference. Consequently, this operating technique is well standardized for the management of this condition.

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INFRARENAL   ABDOMINAL   AORTIC   ANEURYSMS:   TRANSPERITONEAL   VIDEO-ASSISTED   SURGERY

Authors
Abstract
The description of the Infrarenal abdominal aortic aneurysms: transperitoneal video-assisted surgery covers all aspects of the surgical procedure used for the management of (description de la pathologie en cause).
Operating room set up, position of patient and equipment, instruments used are thoroughly described. The technical key steps of the surgical procedure are presented in a step by step way: Introduction, Anatomy, Arterial network, Vein-nerve relationships, Operating room, Trocar placement, Instruments, Exposure, Dissection I, Dissection II, Clamping, Minilaparotomy, Opening the aneurysm, Graft implantation, Closure, Conclusion, Reference.
Consequently, this operating technique is well standardized for the management of this condition.
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2002-05
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E-publication
WeBSurg.com, May 2002;2(05).
URL: http://www.websurg.com/doi-ot02en264.htm

INFRARENAL   ABDOMINAL   AORTIC   ANEURYSMS:   TRANSPERITONEAL   VIDEO-ASSISTED   SURGERY

1. Introduction
Endoaneurysmorrhaphy, as described by Creech (1966), is the treatment of choice for abdominal aortic aneurysms. It can be performed laparoscopically to avoid the general after-effects of laparotomies. The transperitoneal approach permits an initial dissection of the aortic neck and notably facilitates control of the right collateral branches.
These operations can be carried out by teams with good experience in laparoscopic surgery.
2. Anatomy
• Generalities
Abdominal aortic aneurysms arise immediately below an infrarenal aortic neck of varying length. They extend to the aortic bifurcation and can involve the iliac arteries either symmetrically or asymmetrically. In addition to the extension of the aneurysms, it is important to study their degree of calcification and the possibility of coexisting obstructive aorto-iliac lesions or lesions of the collateral arterial branches (mesenteric arteries, renal arteries).
• Intraperitoneal structures
• Small bowel loops
Arrangement of small bowel loops
1. Transverse colon
2. Ascending colon
3. Ileo-cecal junction
4. Root of mesentery
5. Ileal loops (vertical)
6. Jejunal loops (horizontal)
7. Descending colon
The abdominal aorta is located posterior to the intestinal loops, which are joined to the posterior wall of the abdomen by the mesentery. During a transperitoneal approach, the surgeon gains access to the posterior leaflet of the peritoneum, to the left of the fourth part of the duodenum, by arranging and retracting the intestinal loops.
There are 14 to 16 small bowel loops, and they have a specific orientation:
- the superior loops (jejunum) are horizontal,
- the inferior loops (ileum) are vertical.
• Root of mesentery
1. Insertion of the gastro-colic ligament on the head of the pancreas
2. Head of the pancreas
3. Ascending colon
4. Superior mesenteric vessels
5. Root of mesentery
6. Root of transverse mesocolon
7. Duodeno-jejunal flexure
8. Right recess of the omental bursa
The root of the mesentery is 15 cm long and 18 cm wide. It forms a broken, oblique line on the lower right where 3 segments can be identified:
- superior/proximal segment: oblique line of the duodeno-jejunal flexure on the inferior margin of the third part of the duodenum;
- middle segment: vertical, short, anterior to the aorta and the inferior vena cava, it contains the mesenteric vessels;
- inferior/distal segment: it courses in an oblique manner towards the ileocecal junction, cephalad to the right common iliac artery, crossing the right ureter and the spermatic or utero-ovarian vessels.
• Duodeno-jejunal flexure
1. Right edge of the esophageal hiatus
2. Diaphragm
3. Celiac trunk
4. Abdominal aorta
5. Superior mesenteric artery
6. Duodeno-jejunal flexure
7. Inferior ligament of Treitz
8. Tail of the pancreas
9. Left edge of the esophageal hiatus
10. Abdominal esophagus
The root of the mesentery surrounds the duodeno-jejunal flexure and follows an oblique course caudad and to the right, crossing the anterior surface of the fourth and then the third portion of the duodenum.
The duodeno-jejunal flexure is attached by a small muscular ligament, the Treitz ligament, which is 3 to 4 cm long and is fixed inferiorly to the summit of the duodeno-jejunal flexure on the left crus of the diaphragm and around the aortic orifice.
3. Arterial network
1. Inferior diaphragmatic artery
2. Hepatic artery
3. Right renal artery
4. Infrarenal abdominal aorta
5. Lumbar artery
6. Right common iliac artery
7. Right external iliac artery
8. Right internal iliac artery
9. Ilio-lumbar branch (of the internal iliac artery)
10. Median sacral artery
11. Inferior mesenteric artery
12. Left gonadal artery
13. Superior mesenteric artery
14. Splenic artery
15. Celiac trunk

Control of the collateral branches of the infrarenal abdominal aorta, such as the gonadal, lumbar, median sacral and inferior mesenteric arteries, is an essential step of the procedure.

The renal arteries originate on the lateral surfaces of the abdominal aorta, at L1-L2 level, between the superior mesenteric artery proximally and the gonadal arteries distally. The origin of the left renal artery is generally higher than that of the right renal artery.

The inferior mesenteric artery (IMA) originates on the anterior surface of the abdominal aorta, 1 to 3 cm below the third part of the duodenum. It supplies blood to the left colon.

The gonadal arteries arise from the anterior surface of the aorta, facing L2, below the ipsilateral renal artery and above the IMA. They have an oblique course caudally and laterally.

There are 4 pairs of lumbar arteries originating on the postero-lateral surface of the terminal aorta. A more or less chronic obstruction of some of these arteries is linked to arteriosclerosis of the aortic wall and to the thrombus that lines the intima of the aneurysmal vessel.

The median sacral artery is a branch of the median trifurcation of the abdominal aorta. It runs posterior to the left common iliac vein and adjacent to the median sacral vein.
4. Vein-nerve relationships
• Warning
The relationships of the infrarenal aorta and iliac arteries with the inferior vena cava and iliac veins as well as with the presacral nerve structures account for the risks involved when dissecting abdominal aortic aneurysms.
• Left renal vein
Course and relationships of the renal veins
1. Right adrenal gland
2. Right kidney
3. Right renal vein
4. Right ureter
5. Inferior vena cava
6. Infrarenal abdominal aorta
7. Left spermatic pedicle
8. Left ureter
9. Left renal vein
10. Left kidney
11. Left adrenal gland
The left renal vein (LRV) has a 7 cm course that crosses the anterior surface of the aorta below the superior mesenteric artery, forming a vascular bridge. Exceptionally, the LRV has a retroaortic course. The LRV drains the ligament of Treitz and the duodeno-jejunal flexure.
• Venous system
Anterior view of the aortico-caval confluence
1. Inferior vena cava
2. Abdominal aorta
3. Fourth anterior sacral foramina
4. Presacral vessels
5. Left external iliac artery
6. Left internal iliac artery
7. Left common iliac artery
The caval confluence is located to the right and posterior to the aortic bifurcation. The common iliac veins, posterior to the common iliac arteries, are at risk of injury during the operation.
The inferior vena cava arises from the confluence of the 2 common iliac veins and its abdominal portion extends superiorly over 18 cm. Four pairs of lumbar veins drain into the inferior vena cava, with a longer course for the left lumbar veins that run behind the aorta.
• Inferior mesenteric vein
Relationships of the proximal sigmoid colon
1. Duodeno-jejunal flexure
2. Transverse colon
3. Superior mesenteric vessels
4. Inferior mesenteric artery
5. Inferior mesenteric vein
6. Secondary root of the mesosigmoid
7. Distal sigmoid colon
The inferior mesenteric vein (IMV) courses to the left of the artery, and then forks off laterally towards the fourth portion of the duodenum.
5. Operating room
• Principles
The positioning of the patient plays an important role in preventing complications (nerve injury of the brachial plexus or of the peroneal nerve, or cutaneous injury in the right subaxillary area), and also in preparing for instrument placement and anesthetic monitoring equipment.
• Patient
- transitional tilting of the table in a 20° to 25° Trendelenburg position and a 5° to 10° right rotation;
- sandbag placed in the lumbar area;
- right shoulder support to prevent the patient from sliding upwards while in the Trendelenburg position;
- wedges on the right thorax and on the external surface of the lower part of the right thigh;
- right arm alongside the body;
- left arm at a right angle;
- gastric and urinary catheter;
- Swan-Ganz catheter if deemed necessary by the anesthesiologist;
- warming device.
• Team
The operation is performed by a team with 2 assistants (especially if the surgeon is not experienced in the technique) and a scrub nurse.
The team remains in the same position during the laparoscopic dissection. The surgeon can either move to the patient’s right or remain on the left during the implantation of the aortic graft.
1. Surgeon
2. First assistant
3. Second assistant
4. Scrub nurse
5. Anesthesiologist
• Equipment
1. Laparoscopic unit
The standard operating table should be able to move in and out of Trendelenburg and right rotation positions. Two rests are placed to the right of the patient and a shoulder support is placed above the right shoulder. The lateral rails should be designed to accommodate retractors. The laparoscopic unit faces the patient’s right shoulder. It includes a main monitor, a 3CCD camera (required for optimal conditions) and a high-flow insufflator (>= 9 L/min) that can control the pressure electronically. It must have slight inertia to make up for loss of CO2 (induced or not).
The robotic arm is voice controlled.
6. Trocar placement
• Principles
Four 10-12 mm trocars are required. It is possible, with experience, to replace the left inferior trocar (C) with a 5 mm trocar.
Two to three additional incisions are needed:
1. A 3.5 mm incision is used to introduce the metallic arm of the laparoscopic intestinal retractor; this opening is situated on the right border of the supraumbilical midline, at the precise location of the projection of the duodeno-jejunal flexure on the anterior abdominal wall;
2. A second incision is used for a proximal laparoscopic aortic clamp that is 12 mm in diameter (10 mm or even 8 mm clamps will be available soon);
3. A third incision is sometimes required for a distal laparoscopic aortic clamp (12 mm in diameter), which is often replaced by iliac (bulldog) clamps or by occlusion of the iliac axes when there is a jump of one or both bypass limbs to one or both femoral axes.
It is essential that the trocars do not move within the wall. This is achieved with a cutaneous incision adapted to the size of the trocar and by fixing the trocar to the wall with a suture. 'Screwing' systems involve a risk of parietal trauma.
• First trocar
Trocar A is inserted at umbilical level with an open technique. A balloon-tipped trocar is usually used to obtain effective aerostasis during the creation of the pneumoperitoneum. This trocar is used by the second assistant to temporarily maintain a 5-pronged retractor or to manipulate a laparoscopic suction-irrigation device.
• Other trocars
• Trocar B
1. Atraumatic laparoscopic needle holder
2. Suction-irrigation device
3. Resection device (monopolar scissors, high-frequency grasping forceps, clips, staplers), bipolar grasping forceps
4. Curved vessel retractor
Trocar B, 10-12 mm, is used to introduce the polypropylene mesh that is one of the components of the laparoscopic intestinal retractor.
It is inserted under internal visual guidance at the level of the 11th left rib.
At the end of the procedure, it can be replaced by a 15 mm trocar for introduction of the linear stapler.
• Trocar C
1. Babcock clamp
2. Fenestrated grasping forceps
3. Atraumatic laparoscopic needle holder
This is a 5 mm operating port and is used for a retractor during the dissection of the anterior and lateral surfaces of the aorta and common iliac arteries.
During the operation, it may be replaced by a 10 mm trocar for introduction of a linear stapler.
Trocar C is situated anterior to the left anterior superior iliac spine, 8 to 10 cm from trocar B. It forms a triangle with trocar B and trocar D (camera).
More rarely, it is used for a suction-irrigation device, curved vessel retractor or clips.
• Trocar D
This 30°, 10-12 mm camera trocar is positioned 3 to 6 cm to the left of the umbilicus. The narrower the abdominal cavity is after the creation of the pneumoperitoneum, and the wider the anterior development of the aneurysm, the closer the trocar should be inserted to the umbilicus. During the insertion of this trocar, care must be taken to avoid injuring the epigastric artery that courses in the abdominal wall.
7. Instruments
• Optical devices
Most authors use a 30° laparoscope. Laparoscopes with a 0° visual axis and a 70° visual field are used rarely.
• Operating devices
• Main operating devices
1. Babcock clamp
2. Bipolar grasper
3. Ultrasonic dissectors
4. Scissors
5. Needle holder
6. Curved vessel retractor
7. Clip applier
8. Suction-irrigation device
9. Linear stapler
It is important to note that the insufflation of CO2 precludes the use of the blood recuperation device on the suction cannula (saturation of the blood with CO2).
The suction-irrigation device must frequently evacuate the lymphatic fluid and blood without aspirating too much CO2.
• Clamps
1. Short right aortic clamp
2. Long right aortic clamp
3. Reverse angle aortic clamp
4. Endoscopic bulldog applier
5. Bulldog clamps
Several types of clamps have been developed. Laparoscopic aortic clamps have an articulation immediately above their jaws and a round body measuring 10 to 12 cm in diameter that bends inwards for ease in application. They are used without a trocar, via a simple transparietal 9-11 mm incision. Air seal is obtained by their contact with the abdominal wall.
Bulldog clamps come as a set of small straight and curved clamps. This set is used to clamp the common iliac arteries as well as the other collateral vessels of the aorta (renal arteries, inferior mesenteric artery, etc). Each clamp is placed on forceps that can be introduced either through a 10-12 mm trocar or via minilaparotomy. The clamp is opened with the forceps and is then closed over the artery. The forceps are then removed, leaving the clamp in the abdomen until it is removed with the forceps that are reintroduced into the abdomen at the end of the procedure.
• Retractors
A 5-pronged retractor is often used to temporarily retract the bowel before placing the laparoscopic intestinal retractor, which is made up of 3 elements assembled in the abdominal cavity.
• Arm of bowel retractor
• Metal arm for mesh
1. The rigid metal arm measures 3.5 mm in diameter. It is introduced without a trocar through a 3 mm parietal opening to ensure air seal. This opening should be made at the level of the projection of the duodeno-jejunal flexure on the anterior abdominal wall.
The intra-abdominal, horizontal part of this arm is designed to follow the root of the mesentery. The vertical part passes through the abdominal wall and is then fixed to the operating table.
• Polypropylene mesh
2. The dimensions of the mesh are adapted to the length of the metal arm of the bowel retractor. The mesh has a longitudinal cuff along one side.
The mesh is introduced into the abdomen through trocar B. The intra-abdominal part of the metal arm is threaded though the mesh’s cuff.
• Traction sutures
3. Five 12 cm braided sutures are used. They are threaded onto a straight needle and each has a plastic-covered disk (8 mm in diameter) on their other end. These sutures are introduced through trocar B and are used to attach the upper part of the polypropylene mesh to the right abdominal wall.
8. Exposure
• Generalities
• Principles
As in conventional open surgery, all laparoscopic procedures begin with an exploration of the abdominal cavity. It is initially panoramic, to assess the quality of the preoperative gastrointestinal (GI) preparation by the degree of dilation of the small intestine. The surgeon also looks for areas of adhesion (greater omentum-parietal peritoneum), which may be present even in patients who have never undergone abdominal surgery.
The transperitoneal approach to an abdominal aortic aneurysm is difficult because of the depth of the operative field. Excellent exposure is therefore mandatory. This is related to the volume of the working space in the abdominal cavity, which depends on the following:
- the morphology of the patient (patients with flaccid obesity have the largest spaces);
- the presence or absence of intra-abdominal adhesions;
- the quality of the GI preparation.
Correct positioning of the patient and perfect understanding of the organization of the operating field are essential.
• Potential difficulties
Obesity with a flaccid muscular wall is not a major handicap, since the working space remains large. In obesity with a tonic muscular wall and short, fatty mesenteries, the intestinal loops must be arranged by increasing the tilt of the operating table until the laparoscopic intestinal retractor has been placed.
Intraperitoneal adhesions (which may be present even when there is no history of abdominal procedures) are identified during the exploration of the peritoneal cavity. These adhesions must be resected if they hamper the surgeon in arranging the bowel.
• Working space
• Intestinal preparation
Complete emptying of the digestive tract facilitates the arranging of intestinal loops. It is achieved by a strict, fiber-free diet 10 days prior to surgery.
• Position of the patient
The patient is maintained in place with a shoulder support placed at the level of the right shoulder, and by 2 rests placed on the right, one opposite the shoulder and the other opposite the lower part of the thigh. This way, the patient remains in a 25° Trendelenburg position with a 10° right tilt until the laparoscopic intestinal retractor has been placed.
• Pneumoperitoneum
Complete relaxation of the muscular wall increases the working space. The pressure of the pneumoperitoneum is maintained at 8 mm Hg during all laparoscopic steps of the operation.
• Arranging the bowel
• Principles
The arrangement of the intestinal loops requires gravity and organ retraction. The small intestinal loops are arranged on the right surface of the aorta until the laparoscopic bowel retractor is placed.
• Transverse colon
1. Liver
2. Greater omentum
The greater omentum and the transverse colon are arranged in the right subphrenic area. They are maintained in this position with a traction suture that is first inserted through an appendix epiploica and then through the wall.
• Small intestine
1. Abdominal aneurysm
2. Left colon
The jejunum is arranged towards the right hypochondrium, below the right transverse mesocolon, while the ileum is placed in the right iliac fossa. The loops are kept in place by the Trendelenburg position and the right tilt of the operating table. A 5-pronged retractor introduced through trocar A may be used.
• Introducing retractor arm
• Principle
1. Duodeno-jejunal flexure
The incision for the transparietal penetration of the metal arm of the bowel retractor must be placed vertically to the projection of the duodeno-jejunal flexure on the anterior abdominal wall. To properly localize this 3.5 mm opening, trials may be done with an 8 or 9 gauge needle.
• Polypropylene mesh
When the metal arm has been placed in the peritoneal cavity, the polypropylene mesh with its longitudinal cuff is introduced through trocar B. Under videoscopic control, the cuff of the mesh is slipped around the metal arm. It is important to make sure that the distal end of the metal arm emerges from the mesh, on the other end of the cuff.
• Fixation 1
To prevent secondary slipping of the mesh along the metal arm, it is necessary to rapidly attach the proximal part of the mesh close to the insertion of the arm. This is done by introducing a traction suture into the abdomen through trocar B. The thread passes through the mesh and then through the abdominal wall.
• Fixation 2
After confirming that the angle of the metal arm is well positioned in the duodeno-jejunal flexure, the intra-abdominal part of the arm is applied along the root of the mesentery, on the right border of the aorta and the right common iliac artery. When the arm has been correctly positioned, it is fixed to the operating table. Finally, 2 or 3 additional traction sutures are placed through the middle and distal parts of the mesh. It can now effectively retract the bowel.
Once the laparoscopic intestinal retractor has been positioned correctly, the Trendelenburg position can be reduced from 25° to 5°, and the right tilt from 10° to 5°.
9. Dissection I
• Principles
Unlike aortic dissection via a retroperitoneal approach (ascending dissection beginning at the level of the left common iliac artery), aortic dissection via the transperitoneal approach begins with an initial freeing of the aneurysmal neck. The aorta may be clamped above the aneurysm in case of unexpected difficulties during dissection.
Before beginning the dissection, it is important to make sure that the transverse mesocolon does not hinder the freeing of the duodeno-jejunal flexure.
• Peritoneal incision
1. Peritoneal incision
2. Duodeno-jejunal flexure
3. Ligament of Treitz
4. Aorta
The peritoneum is incised caudad to cephalad, starting from an avascular area just to the left of the fourth portion of the duodenum. This incision is extended in the direction of the duodeno-jejunal flexure, towards the ligament of Treitz, which must be divided.
The IMV is the landmark for dissection on the left. It may interfere with dissection when it courses in contact with the duodeno-jejunal flexure. It must then be divided between 2 clips to open the dissection space.
• Neck of aneurysm
1. Duodenum
2. Left renal vein
3. Neck
4. Aorta
In the retroperitoneal space, lympho-vascular tissue can be seen in thin patients, and abundant fatty tissue is found along with the lymph-vascular tissue in obese patients. The dissection must be performed carefully and progressively with step-by-step hemostasis of this preaortic tissue.
The surgeon must pursue the opening of the peritoneum as proximal as possible to facilitate deep dissection towards the neck of the aneurysm. It is usually necessary to free the IMA beforehand, or to simply control the right and left lateral surfaces of the aneurysmal neck.
The inferior border of the left renal artery is the superior landmark for the dissection. The gonadal arteries are almost always found at the anterior surface of the aorta and must be divided (between 2 clips, or preferably with high-frequency forceps).
10. Dissection II
• Control of the IMA
1. Infrarenal aortic aneurysm
2. IMA
3. Division of the IMA
Often caught in the periaortic inflammation, the trunk of the IMA may be difficult to free because of the presence of an occasionally hemorrhagic venous plexus. It is helpful to use an atraumatic, curved vessel retractor for this step.
If preoperative studies indicate thrombosis, or if it can be occluded without danger, the IMA is divided with high-frequency forceps or between 2 clips. In all other cases, it is preferable to examine the IMA and check its flow after opening the aortic aneurysm to decide whether a reimplantation is required.
• Freeing
1. Right and left common iliac arteries
2. Bifurcation
Dissection of the IMA generally frees the retroperitoneal attachments that interfere with aortic dissection. It is then easier to reach the bifurcation by incising the median peritoneum anterior to the promontory. The anterior surface of the aorta is progressively exposed, followed by exposure of the left common iliac artery, which can be entirely freed in certain patients, though only partially in others. The first few centimeters of the right common iliac artery are then dissected.
While freeing the common iliac arteries, the dissection of their postero-internal surfaces involves a risk of vein injury, especially to the common iliac veins and their branches. This part of the dissection must be done extremely carefully, using atraumatic instruments (curved vessel retractor). It can be avoided if aorto-aortic restoration is done with a straight graft, in which case a simple clamping of the lateral surfaces of the common iliac arteries may be sufficient.
• Lumbar arteries
1. Clipped left lumbar artery
At this point in the procedure, only the left lumbar arteries can be freed and occluded using clips. In certain patients, this dissection is made difficult by the fatty and lymphatic tissue that surrounds these vessels and that is often hemorrhagic.
• Right aortic surface
This final step of the dissection should not be performed until the anterior surface and left side of the aorta have been sufficiently freed.
The anterior surface of the aneurysm can interfere with the dissection of the right side. It is therefore advisable to place the operating trocars and the optical trocar D closer to the midline in case of a large aneurysm with anterior protrusion.
The main risk here is to the inferior vena cava. As in conventional surgery, this risk is avoided by performing the dissection against the aortic wall.
Once the aortic-iliac dissection has been achieved, it easier to reach the aortic neck and to free its posterior surface if necessary. Often the occlusion of the right lumbar arteries with clips requires preliminary proximal aortic clamping.
11. Clamping
• Principle
While is preferable to introduce the proximal aortic clamp laparoscopically, the iliac clamps are often easier to introduce via minilaparotomy.
• Proximal aortic clamp
Two types of proximal laparoscopic aortic clamps may be used:
1. Straight aortic clamp
2. Reverse angled aortic clamp
• Straight aortic clamp
1. Straight aortic clamp
The aortic clamp is introduced laparoscopically through a 10 mm longitudinal incision, placed at the level of the neck of the aneurysm, without using a trocar. Before making this incision, in order to make sure that it is correctly placed, it is advisable to insert an intramuscular needle and to check its point of projection on the aorta with the laparoscope.
While introducing the clamp, it is important to verify that the hinge between its jaws has completely entered the peritoneal cavity before opening it. Depending on the size of the patient and of the aorta, a long or short aortic clamp may be used. When opening the clamp, the surgeon should use the laparoscope to make sure that the jaws are correctly positioned laterally and that the neck of the aorta is fully clamped.
• Reverse angled clamp
1. Reverse angled aortic clamp
This clamp is particularly useful if the neck of the aorta angles towards the left, or if it seems that it will be difficult to sew the back wall.
It is introduced through the incision of trocar C after removing the trocar. The penetration of the tip of the clamp to the hinge of its jaws is achieved under laparoscopic guidance. The clamp is then opened and the inferior jaw is placed on the posterior surface of the aortic neck.
12. Minilaparotomy
• Operative strategy
After stopping the insufflation, all trocars are removed. Only the laparoscopic intestinal retractor is left in place. A 6 to 9 cm median minilaparotomy, which is usually supraumbilical, is then performed. The incision is begun at the trocar A incision. The minilaparotomy should take several factors into consideration:
If an aortic tube is used, the minilaparotomy should be centered on the mid-portion of the aneurysm to perform the 2 aortic anastomoses by alternating traction on the wall (upwards and then downwards).
If an aorto-bifemoral bypass is performed, the minilaparotomy is shifted slightly towards the proximal aortic neck.
If an aorto-iliac or aorto-ilio-femoral bypass is performed, the minilaparotomy must be longer (9 to 10 cm).
• Body habitus of patient
In obese patients, especially in those with thick mesenteries, a longer minilaparotomy incision is required.
• Suturing difficulties
For various reasons (aorta with inflammation or with a fragile wall, periaortic adhesions) it may be necessary to enlarge the minilaparotomy, usually upwards. Experience has shown that the postoperative course depends very little on the length of the minilaparotomy, especially when compared to the risks related to a poorly performed aorto-prosthetic anastomosis.
• Minilaparotomy
1. Suction cannula
The surgeon may remain on the patient’s left or move to the patient’s right, opposite the first assistant. A 6 to 9 cm cutaneous incision is made, which may be slightly longer on the underlying adipose and aponeurotic planes.
As soon as the CO2 has been evacuated from the peritoneal cavity, it is possible to connect the cell saver to the end of the suction cannula. At the same time, a normal dose of an intravenous bolus injection of heparin is administered by the anesthesiologist.
The remainder of the procedure is performed under the surgeon’s direct vision in the abdominal cavity. The laparoscopic retractor for the intestinal loops enables the surgeon to view the abdominal aortic aneurysm that has just been dissected. Self-retaining retractors are placed on each side of the incision and maintain exposure.
13. Opening the aneurysm
The proximal aortic clamp is closed using the security notch. The bulldog clamps are applied on the common iliac arteries. The aneurysm is first opened longitudinally, and then on the right and left lateral surfaces on both ends of the incision. The mural thrombus is removed and sent for bacteriologic culture. It is then possible, via an endo-aneurysmal approach, to occlude the lumbar arteries (the right, in particular) that have a backflow. This is achieved with a non-absorbable figure-eight suture. This step may need to be repeated on the median sacral artery.
If there is doubt concerning the advantage of a direct reimplantation of the IMA, the bulldog clamp can be released for a few instants to evaluate the quality of the backflow.
14. Graft implantation
• Proximal anastomosis
1. Proximal aortic cuff
2. Opened aneurysm
3. Aortic graft
4. Running suture being performed, with medial to lateral insertion of the needle in the aorta
5. Biological glue
A polyester or polytetrafluoroethylen graft is chosen that is adapted to the diameter of the aortic neck and the type of bypass being done (aortic tube or bifurcated graft).
The body of the graft is cut to form a slightly oblique slant. Double-threaded 3.0 or 4.0 vascular suture, 1.2 m in length, is used.
The surgeon performs a conventional end-to-end anastomosis of the graft to the aorta while the first assistant maintains the suture under tension. The seal of this anastomosis is tested at the end of the procedure and biological glue is often added.
• Distal anastomoses
• Aorto-aortic tube
It is often necessary to reapply the self-retaining retractors to exert a slight downward traction on the wall. Calcifications and plaques may mandate modification of the distal anastomosis.
Two bulldog clamps were previously applied to the origin of the common iliac arteries. The distal part of the straight graft is cut with a slight slant to the desired length and a second, conventional anastomosis of the graft to the aorta is performed following the method described above.
• Bypass 2
Aorto-iliac bypass: when the aneurysm involves the bifurcation, distal anastomoses on the first few centimeters of the common iliac arteries are performed, above the previously applied bulldog clamps. The origin of each iliac artery is opened longitudinally and transversally. Each branch of the bifurcated graft is cut with a slant to the desired length.
A conventional end-to-end anastomosis on the graft to the common iliac artery is performed on each side, using 4.0 or 5.0 vascular suture.
• Bypass 3
Aorto-bifemoral bypass: involvement of the aneurysm down to the common iliac arteries requires an extension of the bypass to the common femoral arteries, or occasionally to the external iliac arteries.
In these cases, a classical approach via the right and left femoral triangles is used at the beginning of the procedure, before the abdominal approach. During this approach, and to avoid a secondary CO2 leak through the inguinal incisions, the arterial dissection below the crural arch must not be pursued.
During the abdominal approach, the common iliac arteries may be occluded with sutures or a linear stapler. Each branch of the graft must be placed in a subperitoneal anatomical position. A standard curved aortic clamp is introduced through the femoral triangle towards the aortic area. To guide the clamp during its insertion, the surgeon places his or her hand in the abdomen through the minilaparotomy.
Once each branch of the graft is exteriorized at the level of the femoral triangles, a conventional femoral-graft anastomosis is carried out with a 5.0 or 6.0 vascular suture. This anastomosis is done in an end-to-side fashion, permitting retrograde perfusion of the internal iliac arteries via the external iliac arteries.
• Bypass 4
Aorto-ilio-femoral bypass: if the aneurysm extends down asymmetrically, requiring a bypass onto one of the femoral axes, a limb of the graft is anastomosed to a common iliac artery. The other limb is passed into a retroperitoneal anatomical position and laterally anastomosed to the femoral bifurcation.
• Special cases
• Case 1
Bypass onto the iliac bifurcations: in the specific case where one or both internal iliac arteries must be perfused in an anterograde way (abdominal aortic aneurysm extending onto the origin of one or both internal iliac arteries) it is necessary to perform one or two anastomoses of the grafts to the iliac bifurcation(s).
On the left side, the laparoscopic dissection, which can be extended by an enlarged downward minilaparotomy, usually permits the surgeon to reach the iliac bifurcation and to perform the graft to iliac anastomosis at this level.
On the right side, laparoscopic dissection of the iliac bifurcation is difficult. A complementary 5 to 7 cm cutaneous incision (in the right flank) is usually preferable. The right iliac bifurcation can be reached by a retroperitoneal approach through this incision. The right limb of the graft can be easily placed in anatomical position.
• Case 2
Combined aorto-ilio-femoral occlusive lesions: the association of severe occlusive lesions with an abdominal aortic aneurysm is not frequent. It should be suspected in the presence of symptoms involving the legs (intermittent claudication, ischemic pain at rest or ischemic trophic disorders, disappearance of pulse). Systematic preoperative CT scan with contrast can often reveal occlusive lesions. In the presence of these signs, aorto-arteriography of the legs is mandatory.
In most cases, the type of bypass performed is an aorto-bifemoral restoration that takes this information into account.
• Case 3
1. Left inferior polar renal artery
2. IMA
Reimplantation of the IMA: the decision to reimplant the IMA into the left surface of the body of the graft or into the left branch of the bifurcated aortic graft can be made either before the procedure following the preoperative workup (occlusion of one or both internal iliac arteries) or if weak backflow is discovered when releasing the clamp from the IMA after opening the abdominal aortic aneurysm.
As in conventional surgery, an aortic patch is cut around the IMA ostium and reimplantation is performed through the minilaparotomy with a running 5.0 or 6.0 vascular suture.
15. Closure
• Closure
After placement of the graft and checking hemostasis, a retroperitoneal closure can be performed through the minilaparotomy, using slowly absorbable suture.
• Removal of the retractor
The scrub nurse should count the sponges to make sure that they have all been removed from the abdomen. The laparoscopic bowel retractor is then dismantled. The traction sutures should first be cut outside the abdomen and their internal portion (plastified cuff) recuperated. The metal arm of the bowel retractor is then detached from the operating table. The polypropylene mesh is removed through the minilaparotomy. The metal arm is slipped out of the abdomen through the opening into which it was inserted.
• Parietal closure
The minilaparotomy and the trocar wounds are closed in 2 or 3 planes, in a conventional fashion without drainage. If necessary, the femoral triangles are closed in 3 planes over a drain.
16. Conclusion
Video-assisted endoaneurysmorrhaphy for abdominal aortic aneurysms can be used to obtain the same results as in conventional surgery, with a less aggressive abdominal approach.
Early results have shown a decrease in postoperative pain and in the risk of nosocomial infection. Bowel function is rapidly restored and the patient can usually be discharged from the hospital between POD3 and POD6. In our experience, no delayed reoperations of the abdominal area were necessary (mean follow-up: 22 months, 3-36 month range) (Alimi et al., 2001).
Other authors (Edoga et al., 1998) have described a retroperitoneal laparoscopic approach with encouraging results. For surgeons who are not yet experienced in the technique, a transperitoneal approach using the “less dominant” hand introduced through the minilaparotomy, while maintaining a pneumoperitoneum, can be a reassuring option (Kolvenbach et al., 2001).
In the future, the development of new instruments will make it possible to decrease the operative time and the duration of the clamping, which are still slightly longer than for conventional surgery. It is probable that it will even be possible to avoid the minilaparotomy in certain patients.
The smooth performance of video-assisted endoaneurysmorrhaphy for abdominal aortic aneurysms depends on:
- the quality of the equipment;
- adherence to the operative strategy, which is the same as that used in conventional surgery;
- the experience of the surgical team in laparoscopic techniques.
After training on animals or cadavers, these techniques should be practiced with a highly skilled team. Comparative clinical studies of good methodological quality, involving a sufficient number of patients, will be needed to assess this technique.
17. Reference
Alimi YS, Hartung O, Valerio N, Juhan C. Laparoscopic aortoiliac surgery for aneurysm and occlusive
disease: when should a minilaparotomy be performed? J Vasc Surg 2001;33:469-75.
Creech O, Jr. Endo-aneurysmorrhaphy and treatment of aortic aneurysm. Ann Surg 1966;164:935-46.
Edoga JK, Asgarian K, Singh D, James KV, Romanelli J, Merchant S et al. Laparoscopic surgery for
abdominal aortic aneurysms. Technical elements of the procedure and a preliminary report of the first
22 patients. Surg Endosc 1998;12:1064-72.
Kolvenbach R, Ceshire N, Pinter L, Da Silva L, Deling O, Kasper AS. Laparoscopy-assisted aneurysm
resection as a minimal invasive alternative in patients unsuitable for endovascular surgery. J Vasc
Surg 2001;34:216-21.