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Role of preoperative embolization in laparoscopic splenectomy
作者群
摘要
The description of the role of preoperative embolization in laparoscopic splenectomy covers all aspects of the surgical procedure used for the management of hypersplenism.
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: embolization principles, risks, benefits.
Consequently, this operating technique is well standardized for the management of this condition.
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: embolization principles, risks, benefits.
Consequently, this operating technique is well standardized for the management of this condition.
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媒體類型
 刊物
2001-03
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普通的
最愛
 音訊
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數位出版
WeBSurg.com, Mar 2001;1(03).
URL: http://www.websurg.com/doi-ot02en200a.htm
URL: http://www.websurg.com/doi-ot02en200a.htm
Role of preoperative embolization in laparoscopic splenectomy
1. Introduction
Splenic surgery is often associated with a high risk of hemorrhage due to the rich vascular supply of the spleen.The development of minimally invasive (laparoscopic) surgery for the spleen has increased this risk. This is partly due to the instruments utilized and to the potential delay in converting to open surgery in case of bleeding. Relatively large blood losses (up to 1500 mL) have been reported in early experiences with laparoscopic splenectomy, leading to high conversion rates and postoperative blood transfusions.
2. Anatomy
• Generalities
The spleen is an organ situated in the left hypochondrium. It plays a role both in the functioning of the immune system and in regulating red blood cell formation. It is the most vascularized organ in the body. Its parenchyma is fragile.
Resection of the spleen via laparoscopy requires advanced laparoscopic skills and strong discipline.
• Topography
• Location
The spleen is situated in the left upper abdominal quadrant.The axis of the spleen corresponds to the axis of the 10th left rib. Depending on the patient's morphological type, this axis may vary. In obese patients or those with short limbs, the position of the spleen is high, deep, and almost horizontal.
• Diaphragmatic surface
The diaphragmatic or posterior-external surface is convex and entirely covered with peritoneum.• Renal surface
The renal or inferior-internal surface is concave, faces downwards and inwards, and is covered with peritoneum.The apex or postero-superior aspect is curved and lies in the region of the 10th intercostal space.
• Gastric surface
The gastric or antero-internal surface is concave, faces inwards and anteriorly, and contains the splenic hilum.• Colonic surface
The colonic or antero-inferior surface is slightly concave and faces caudally, medially, and slightly anteriorly.• Means of attachment
• Pancreaticosplenic ligament
The spleen is fixed in the left hypochondrium to neighboring anatomical structures by ligaments.The pancreaticosplenic ligament (1) attaches the posterior margin of the hilum to the pancreatic tail and to the splenic vessels on the lower renal surface of the spleen. This peritoneal fold is referred to as the mesentery of the spleen. It ranges from 3 to 8 cm in length. The longer the ligament is, the easier the splenectomy will be to perform.
• Gastrosplenic ligament
The gastrosplenic ligament (2) attaches the anterior margin of the hilum to the greater curvature of the stomach, on the gastric surface of the spleen. It contains the short gastric vessels and the gastroepiploic artery, which are branches of the splenic artery.• Phrenicosplenic ligament
The phrenicosplenic ligament (3) attaches the diaphragm to the apex of the hilum on the upper diaphragmatic surface of the spleen. • Splenocolic ligament
The splenocolic ligament (4) attaches the base of the hilum to the left transverse mesocolon and to the left splenic flexure, on the colonic surface of the spleen. • Phrenicocolic ligament
The phrenocolic ligament (5) is a triangular fold of peritoneum attaching the left flexure of the colon and the diaphragm to the lower portion of the spleen.• Angiography
• Vascular tree
An angiography, performed as a complementary exam before embolization of the spleen, provides detailed images of the vascular anatomy of the hilum. Valuable information concerning possible variations in the blood supply to the region may thereby be obtained.The vascular tree leading to the hilum of the spleen can be categorized as a dense or diffuse distribution.
The structure of the splenic hilum is clearly shown. The plane of dissection can be determined according to the blood supply.
• Dense hilar distribution
The distribution of the terminal branches of the splenic artery is distal to the pancreatic branches, leaving a greater safety margin with the pancreatic branches.• Diffuse distribution
The distribution of the terminal branches is closer to the pancreatic branches and it may be difficult to perform a proximal embolization.3. Indications
The preoperative arterial embolization technique popularized by Poulin et al. (Surg Endosc 1998;12:870-5) to reduce operative risks has obtained good results. Indeed, even with adoption of the lateral approach and adjustment of patient position, laparoscopic dissection remains hazardous and the risk of hemorrhage persists, due to possible bleeding of the short gastric vessels as well as the splenic capsule or parenchyma during manipulation of the spleen with laparoscopic instruments.But as several authors (Poulin et al., Surg Endosc 1998;12:870-5, 1998; Totté et al., Hepatogastroenterology 1998;45:773-6) have demonstrated, selective splenic artery embolization can almost eliminate this operative risk.
Through angiography, the splenic vessels can be visualized preoperatively, making it possible to adapt the technique used to dissect the splenic hilum accordingly. In cases of atypical vascularization, the embolization can be modified and super-selective embolization performed. It is particularly important to identify the origin of the dorsal pancreatic artery or greater pancreatic artery supplying the upper distal part of the pancreas, as their occlusion may lead to life-threatening pancreatitis.
4. Operating room set-up
• Patient
The procedure is carried out in an angiography unit. An interventional radiologist or a surgeon trained in selective or super-selective embolization techniques performs the procedure. The following criteria should be observed:- dorsal decubitus;
- legs slightly apart;
- local anesthesia at the level of the puncture site.
• Team
1. The surgeon stands on the patient’s right.2. If an assistant is present, he or she stands on the surgeon’s right.
3. The anesthesiologist is positioned at the head of the patient.
• Equipment
1. Radiotransparent table2. Radiology equipment
3. Anesthetic equipment
4. Monitors
• Accessories
1. 5F Introducer2. Catheter allowing for a selective or super-selective catheterization of the splenic artery (5 French Cobra catheter)
3. Hand-cut Gelfoam particles
4. Gianturco coils or another type of coil suited for arterial embolization
5. Embolization/principles
• Principles
Angiography provides information on the vascular network of the spleen and identifies the arteries to be embolized.• Puncture/femoral artery
Under local anesthesia, a 5F Cobra catheter is inserted into the right femoral artery via a 5F introducer.• Global arteriography
Once the celiac trunk is catheterized, a contrast medium is injected and the arteriography of all of its branches is performed in order to detect potential anatomical variations in the regional vascular supply.• Selective angiography
Selective catheterization of the splenic artery is pursued up to the hilum of the spleen.A selective angiogram is then obtained. The vascular structure of the spleen is analyzed and the catheter is positioned just distal to the origin of the dorsal pancreatic artery or greater pancreatic artery.
• Embolization
• Objective
Its goal is to occlude all of the arteries supplying blood to the spleen (main artery and accessory artery).• Introduction of Gelfoam
Selective embolization of each individual arterial branch is achieved using hand-cut Gelfoam particles.• Occlusion of main trunk
Occlusion of the main trunk is obtained by 1 or 2 Gianturco coils (5-8 mm) positioned distally to the origin of the dorsal pancreatic artery or greater pancreatic artery.• Danger
Risks related to embolization:- migration of Gelfoam particles;
- capillary occlusion;
- pancreatic and retroperitoneal necrosis.
6. Risks
Procedure-related risks include:- wound infection;
- hematoma;
- intimal dissection;
- pseudo-aneurysm of the femoral artery.
7. Benefits
Benefits:- information about normal or aberrant splenic blood supply;
- decrease in risk of intraoperative hemorrhage;
- detailed anatomical information obtained by angiography;
- decrease in splenic volume.
8. Reference