Consultant general and laparoscopic surgeon

THE SPLEEN
History of the Procedure
In 1893, Reigner published the first documented successful splenectomy in the German literature. Operative mortality rates remained high until the 1950s, when new and rapid advancements in surgical and anesthesia sciences occurred.
ANATOMYEmbryonic development of the spleen begins in the fifth week of gestation as a small cluster of mesenchymal cells in the dorsal mesogastrium between the stomach and pancreas. This mesenchymal tissue rotates to the left as development progress. By the end of the third gestational moth, the organ is formed. Remnants that do not fuse with the main splenic mass, account for thehigh incidence (15%-30%) of accessory spleens in adjacent tissues.
The spleen is a slightly concave, solid, dark red organ of approximately 3 × 8 × 14 cm, weighs between 100-175 gm, and frequently has fetal lobulations on its anterior edge. The spleen posses the 25% of the body´s lymphoid tissue and is the second largest organ of the RES; located in the posterior LUQ of the abdomen protected bythe eight to the eleventh ribs. It is bordered by the left kidney posteriorly, the diaphragm superiorly and the fundus of the stomach and the splenic flexure of the colon anteriorly.
The organ is maintained by avascular suspensory ligaments (splenophrenic, splenorenal, and splenocolic ligaments) and the gastrosplenic ligament (contains the short gastric vessels).The size and thickness of theseligaments vary greatly, with some spleens appearing to be very mobile, while others appear fixed in the LUQ.
The splenic pedicle contains lymphatic structures, vein and splenic artery. The tail of the pancreas is often intimately positioned near the splenic hilum; notably, the splenic vessels may have small branches feeding the body and tail of the pancreas so, care should be taken duringsplenectomy.
The arterial supply to the spleen is derived from the celiac artery from both the short gastric arteries (arise as branches of the gastroepiploic or the splenic arteries) and the splenic artery (major arterial supply) which commonly bifurcates externally to the spleen, supplying upper and lower poles separately (a finding that may make splenorrhaphy much easier for the operating surgeon), toenter the pulp.
The splenic drainage is formed by the short gastric vessels and the splenic vein (coalescence of polar veins in the splenic hilum) that courses with the splenic artery along the dorsal surface of the pancreas to enter the portal system. Veins and lymphatics draining the pulp pass in the trabeculae to leave the spleen at the hilum.
In elderly individuals, in those with priorsplenic injury, irradiation, or recurrent infarction, the splenic capsule may become firm and thickly scarred (“sugar coated”) and adherent to the diaphragm.
The organ itself consists of an outer capsule and trabeculae, which enclose the pulp except for the insertion of the splenic artery and vein and is conventionally divided into:
1. The red pulp so designated due to its gross appearance from thepresence of blood and consists of Billroth cords (cell cords) with sinuses in between, in charge of non immunologic functions.
2. The white pulp is essentially a pN. Are small gray-white zones of lymphatic tissue consisting of lymphocytes, plasma cells, and Mcg, lying within and surrounded by the red pulp. It is the responsible of immune functions.
3. The marginal zone constitutes the interfacebetween the red and white pulp.
Billroth is credited with the open circulation theory, in which either arterioles empty blood directly into tissue spaces or arterial capillaries open into pulp cords, with blood cells then passing through pores in the walls of splenic sinusoids to enter the venous circulation.
Ninety % of splenic arterial flow enters the open circulation of the red pulp,...