Anatomy of splenectomy for ruptured spleen
Executive Summary
The spleen is the most frequently injured organ resulting from abdominal violence. While historically viewed as a functionless organ after fetal development, modern medical understanding recognizes its critical role in the immune system, particularly in protecting against encapsulated bacteria. Consequently, while minor injuries are increasingly treated with conservative, organ-preserving techniques, emergency splenectomy remains a life-saving necessity in cases of severe hemorrhage, pulping, or total avulsion.
Successful surgical intervention requires a deep understanding of the spleen’s complex anatomical relationships, particularly its vascular proximity to the pancreas and its attachments via the lienorenal and gastrosplenic ligaments. Post-operative care is equally vital, requiring long-term antibiotic prophylaxis and vaccinations to mitigate the risk of overwhelming post-splenectomy infection, which is most prevalent in children and the immunosuppressed.
Anatomical Characteristics and Relationships
Physical Description
Dimensions: The spleen is approximately the size of a cupped hand.
Palpation: Under normal conditions, the spleen cannot be felt during abdominal palpation. In an average subject, it must enlarge to three times its normal size before the notched anterior border can be felt below the left costal margin.
Surface Markings: The position of the spleen corresponds to a closed fist placed over the tenth rib posteriorly, roughly 5 cm from the midline.
Internal Structure and Accessory Spleens
The spleen is the body's largest reticulo-endothelial accumulation. It is encased in a thin fibrous capsule with an intimately adherent peritoneum. Fibrous trabeculae extend from the capsule into the splenic pulp.
Accessory spleens may be present in several locations:
Common: Near the splenic hilum.
Other sites: The tail of the pancreas, splenic mesenteries, omentum, small bowel mesentery, and (rarely) the ovaries or testes.
Clinical Significance: While inconsequential in trauma cases, accessory spleens must be removed during splenectomy for conditions like thrombocytopenic purpura or autoimmune hemolytic anemia to prevent the persistence of symptoms.
Vital Relationships and Ligaments
The spleen forms the left lateral extremity of the lesser sac and is held in place by two primary "ligaments" (double folds of peritoneum):
Posterior Relations: The spleen lies against the left diaphragm, separating it from the pleura at the base of the left lung and the ninth, tenth, and eleventh ribs.
Vascular Anatomy
The splenic artery and vein are the primary vessels, though they also serve as the principal vascular supply for the pancreas.
Splenic Artery: Branching from the celiac axis, this vessel is uniquely tortuous—the only such vessel in normal abdominal anatomy. It runs along the superior border of the pancreas.
Splenic Vein: This vessel drains into the portal vein and lies behind the body of the pancreas.
The Hilum: The artery and vein only come into intimate relationship with each other at the splenic hilum, where they enter the organ alongside lymphatics and autonomic nerves.
Splenic Trauma and Clinical Indications
Types of Injury
Splenic injury ranges in severity from subcapsular hematomas and superficial tears to multiple fissure tears, severe organ disruption, and total avulsion of the splenic pedicle. Risk of rupture is significantly higher if the spleen is diseased (e.g., malaria or infectious mononucleosis).
Associated Injuries
Due to its anatomical proximity, trauma to the spleen often involves damage to:
Liver and diaphragm.
Stomach and tail of the pancreas.
Left kidney and mesentery of the small intestine.
Left lung (specifically in cases of posterior stab wounds, which may cause pneumothorax).
Splenectomy vs. Preservation
The shift toward conservative management for minor injuries stems from the risk of overwhelming post-splenectomy infection. The spleen protects against encapsulated bacteria, specifically:
Streptococcus pneumoniae
Haemophilus influenzae
Neisseria meningitidis
Indications for Mandatory Splenectomy:
Pulping or avulsion of the organ.
Severe hemorrhage.
Multiple abdominal injuries where speed is essential for survival.
Surgical Procedure: Emergency Splenectomy
Approach and Incision
The preferred method is a generous upper mid-line incision from the xiphoid to the umbilicus. This approach is favored for its speed and its ability to be extended for a full exploration of the abdominal cavity for associated injuries.
Mobilization and Control
In emergency scenarios, the mobilization of the spleen is performed entirely by touch due to the presence of intraperitoneal blood and clots.
Manual Exploration: The surgeon passes their right hand along the lower aspect of the diaphragm to identify the spleen.
Delivery: The fingers break down the avascular lienorenal ligament, allowing the spleen to be delivered into the wound.
Hemorrhage Control: Holding the damaged organ immediately controls the primary bleeding.
Management of the Vascular Pedicle
Unlike elective surgery where vessels are divided individually, trauma surgery allows the vascular pedicle to be clamped and tied in small segments from the bottom up.
Precaution: Clamps must be placed close to the splenic hilum to avoid injuring the tail of the pancreas.
Hemostasis: Once the splenic stump is secure, blood left in the peritoneal cavity is generally left to be absorbed naturally, as it does no harm.
Post-Operative Management
Following a splenectomy, patients require lifelong vigilance against infection, particularly within the first two years after surgery.
Antibiotic Prophylaxis: Phenoxypenicillin is advised, especially for children.
Vaccination: A triple vaccine against S. pneumoniae, H. influenzae, and N. meningitidis should be administered as soon as possible following surgery.
High-Risk Groups: Prophylaxis is most critical for young children (where infection occurs in 1–2% of post-trauma cases), the immunosuppressed, and those with underlying splenic disease.
