The exact procedure depends upon many factors: the size and mobility of the spleen, the presence of extensive adhesions between the spleen and the parietal peritoneum, the length of the splenic pedicle, the presence of active bleeding from a ruptured spleen, or the patient’s poor general condition as a result of blood dyscrasia. The approach to the immobilization and control of the blood supply of the spleen must be individualized in each case. A thorough understanding of the attachments and blood supply of the spleen is essential (figure 2). In general, it is best to devascularize the spleen prior to mobilizing to minimize capsular trauma.
When splenectomy is indicated for blood dyscrasias, a careful search should be made for an accessory spleen both before and after the spleen is removed and hemostasis is effected. A routine search is made in the following order: the hilar region, the splenorenal ligament, the greater omentum, the retroperitoneal region surrounding the tail of the pancreas, the splenocolic ligament, and the mesentery of the large and small intestines. If accessory spleens are found in two or more locations, one is usually in the hilus. In some cases of blood dyscrasias the clinical course of the patient may suggest recurrence of the disease because of a retained accessory spleen. In such instances not only should the sites mentioned above be searched but the search should also be extended to the adnexa in the pelvis. The spleen must not be lacerated, nor should remnants be left within the abdomen because of the danger of seeding, which may result in splenosis.
The diagram in figure 2 illustrates the anatomic relationships of the spleen. As traction is exerted on the stomach medially, an avascular area in the gastrosplenic ligament may be incised, giving direct entrance to the lesser sac. Several blood vessels in the gastrosplenic ligament are divided and ligated to provide adequate exposure of the splenic artery. Along the upper margin of the pancreas, the tortuous course of the splenic artery can be palpated. The peritoneum over the vessel is incised carefully, and a long right-angle clamp is introduced beneath the artery to isolate it and to facilitate its ligation. The splenic vein is immediately beneath the artery. One or more 00 silk sutures are drawn beneath the artery and carefully tied (figure 3). Alternatively it may be divided with a vascular stapler at this point. Preliminary ligation of the splenic artery has many advantages. It allows blood to drain from the spleen, providing an autotransfusion. The spleen tends to shrink, making its removal easier and with less blood loss. Finally, blood transfusions can be given immediately to the patient with hemolytic anemia. This preliminary step does not prolong the procedure and tends to ensure a safer splenectomy with minimal blood loss.
After the splenic artery has been secured, the remainder of the gastrosplenic ligament is divided between small curved clamps or with an energy device (figure 4). Great care is exercised, especially toward the upper margin of the spleen, to avoid injuring the gastric wall during the application of clamps, for in this area the gastrosplenic ligament is sometimes extremely short. This is especially true when the spleen is very large or in the presence of portal hypertension. Failure to secure the uppermost vein in the gastrosplenic ligament can result in serious blood loss. Because of the danger of postoperative bleeding following gastric dilatation, the vessels along the greater curvature should be ligated with a transfixing suture that includes a bite of the gastric wall. In addition, in this area several vessels commonly extend from the hilus of the spleen over to the posterior wall near the greater curvature high on the fundus. At the inferior margin of the spleen, fairly sizable vessels, the left gastroepiploic artery and vein, commonly will be encountered in the gastrosplenic ligament (figure 4). The contents of the clamps are ligated on both the gastric and splenic sides, since the division of the gastrosplenic ligament will leave a large opening directly into the lesser sac.
The early ligation of the major splenic artery makes mobilization of the spleen easier and safer. The surgeon passes the left hand over the spleen in an effort to deliver it into the wound (figure 5). Dense adhesions may be present between the spleen and the peritoneum of the abdominal wall or the left diaphragm; however, the spleen can usually be mobilized after a few avascular adhesions and the gastrosplenic ligament have been divided.
As the spleen is mobilized, the surgeon passes the fingers over its margin to expose the splenorenal ligament, which should be incised carefully (figure 6). The peritoneal reflection in this area is usually rather avascular; however, it is necessary to ligate many bleeding points in the presence of portal hypertension. Usually, the index finger can be inserted into the peritoneal opening, and by blunt dissection with the index finger of the left hand, which extends over the surface of the spleen, the margin of the spleen can be freed easily (figure 7). This must be done gently since the capsule may be torn, resulting in troublesome bleeding or seeding of splenic tissue.
After the posterior margin of the spleen has been mobilized, the spleen may be brought well outside the abdomen; however, if dense adhesions between the spleen and the parietal peritoneum are encountered, it is easier to incise the overlying peritoneum and carry out a subperitoneal resection, which leaves a large, raw space. This may be safer than attempting to free the spleen with sharp dissection. Warm, moist packs may be introduced into the splenic bed to control oozing. Active bleeding points should be controlled with electrocautery.
When the spleen is mobilized outside the wound, the splenocolic ligament is divided between curved clamps (figure 8). This procedure is carried out carefully in order to avoid any possibility of damage to the colon. The contents of these clamps are ligated with a transfixing suture of 00 silk or absorbable suture. In the presence of portal hypertension, many large veins may be present in this area. The spleen is then retracted medially by the surgeon’s left hand, while the tail of the pancreas, if it extends up to the splenic hilus, is separated by blunt dissection from the splenic vessels in order to avoid damage to it by the subsequent ligation of the pedicle (figures 9 and 10). The surgeon should keep in mind the possibility of accessory spleens in this location. The spleen is held upward and laterally by an assistant, while the large vessels in the pedicle are separated from the adjacent tissues to permit the application of several curved clamps to the individual vessels (figure 11). These vessels should be ligated at the base of the pedicle proximal to the bifurcation of the splenic vessels. Despite the fact that the splenic artery has been ligated previously, it is tied again proximally and transfixed distally (figure 12). The same principle of double ligature for the splenic vein is also carried out. Alternatively, vascular stapler may be liberally applied in this region. In those instances where preoperative transfusions have been contraindicated, they may be started as soon as the splenic artery has been divided. The operative site is searched for evidence of persistent oozing. Warm, moist packs or a coagulant matrix may be introduced to control the small bleeding points. Following this, a final careful search is made for any existing accessory spleens that must be resected.