Spleen

High Yield Anatomy/Physiology

• Main Ligaments (there are more minor ligaments, but these are the most surgically important)
• Gastrosplenic → contains short gastrics
• Splenorenal → contains splenic vessels and tail of pancreas
• Splenocolic
• Splenophrenic
• Spleen functions:
• Store platelets, filter senescent erythrocytes, re-energize erythrocytes through “pitting”, immune function (largest concentration of lymphoid tissue in the body)
• Pitting = removal of intracellular products
• Opsonization: Tuftsin and Properdin
• Red pulp — Filters RBCs — Most of the spleen — Thin walled sinusoids separated by cords containing red cells
• White pulp — Immune functions
• Lymphoid follicles — B-cells
• Periarterial lymphatic sheath (PALS) — T-cells
• Peripheral blood smear suggesting absent/damaged spleen:
• Howell-Jolly body = Nuclear remnants (most reliable finding)
• Pappenheimer body = Iron deposits
• Target cell = Immature RBC
• Heinz body = Intracellular denatured hemoglobin
• Spur cell = Deformed membrane
• What if you don’t see these post-splenectomy
• Accessory spleen

Figure 1 - Figure 1 - Hematologic Consequence of Splenectomy Indications for splenectomy

• Unstable trauma patients
• Hematologic disorders: MC ITP and spherocytosis
• Splenic abscess
• Symptomatic cysts
• Primary malignancies (mainly non-Hodgkins lymphomas) Splenic Trauma
• Can be secondary to iatrogenic trauma from splenic capsular tear with over vigorous retraction during foregut or colon procedures
• Penetrating trauma → splenectomy

• Blunt injury → selective non-operative management

• Patient must be hemodynamically stable without peritonitis → Otherwise emergent laparotomy and splenectomy
• Nonoperative management includes in-hospital or ICU monitoring, serial abdominal examinations, serial hematocrit measurements, and a period of immobility (bed rest/post- discharge restricted activity)
• Angiographic intervention should be considered for:
• AAST grade >III injuries (subcapsular hematoma >50% or expanding; ruptured subcapsular hematoma; laceration >3cm or involving trabecular vessels)
• Presence of contrast blush
• Moderate hemoperitoneum
• Any signs of ongoing splenic bleeding Hematologic Disorders
• Idiopathic thrombocytopenia purpura (ITP)
• Thought to be caused by autoantibodies to glycoproteins IIb/ IIIa and Ia/IIa
• Initial management is medical → Steroids, IVIG
• Splenectomy for medically refractory cases or for recurrence (avoids need for longstanding steroids)
• Patients who have a good response to steroids → predictive of a favorable response after splenectomy
• When do you transfuse platelets?
• Only for intraoperative bleeding → give after ligating splenic artery if possible (prevents consumption of transfused platelets)
• Hereditary Spherocytosis
• Presentation: anemia, splenomegaly
• Autosomal dominant defect in cell membrane protein (spectrin) → RBC less deformable → culled by spleen

• Splenectomy recommended for symptomatic patients older than 6 years old (want them to develop immune function prior to splenectomy)

• Typically, will require cholecystectomy at time of surgery as well (check for gallstones - hemolysis produces bilirubin stones)
• Pyruvate Kinase Deficiency — Congenital hemolytic anemia caused by impaired glucose metabolism - splenectomy reduces transfusion requirements
• Hemoglobinopathies — Sickle cell disease, thalasemias — Rare indication for splenectomy Splenic abscess
• Causes: IV drug use, endocarditis, secondary infection of traumatic pseudocyst, sickle cell disease
• Unilocular with thick wall in stable patient → percutaneous drainage
• Multi-locular, thin walled → suspect echinoccocal abscess → Splenectomy Splenic lesions
• Splenic cyst
• Well defined hypodense lesion without an enhancing rim
• Two types
• True cysts: congenital, parasitic (echinococcus), or neoplastic
• False cysts: post traumatic pseudocyst
• Leave alone if asymptomatic (serology and imaging characteristics can typically rule out parasitic cyst or malignancy)
• Large cysts (>5cm) or symptomatic → Consider laparoscopic cyst excision or fenestration
• Hemangioma = MC splenic tumor → splenectomy if symptomatic
• Angiosarcoma = primary malignant tumor of spleen

• Associated with vinyl chloride and thorium dioxide exposure

• Aggressive, high mortality
• Splenectomy if caught in time
• Non-Hodgkins lymphoma
• MC CLL → Splenectomy for anemia/thrombocytopenia Splenic artery aneurysm
• MC visceral artery aneurysm, more common in women
• When to treat?

• 2cm

• All pregnant women or women of childbearing age, regardless of size (As high as 70% rupture risk during pregnancy
• Treatment → Usually endovascular coil embolization of the aneurysm or placement of covered stent
• Very distal aneurysms may require splenectomy
• Tradition open or laparoscopic splenic artery ligation also acceptable options Post splenectomy infection
• Decreased IgM and IgG leads to increased susceptibility to encapsulated organisms (S . pneumoniae, N . meningitidis, H . influenza)
• Timing of vaccination?
• 2 weeks prior to elective splenectomy or prior to hospital discharge following emergent splenectomy (or 2 weeks post-op if reliable follow-up)
• OPSI risk is higher in children — especially in hematologic disease (Beta thalassemia)
• If suspicion of OPSI → Broad spectrum antibiotics immediately! — Don’t wait for cultures
• Prophylactic antibiotics?
• Consider for children <10 years old
• Definitely not in adults

Quick Hits

• Patient s/p splenectomy for ITP with persistent thrombocytopenia . Periepheral smear with Howel-jolly bodies?
• Accessory spleen
• Diagnose with imaging: radionuclide spleen scan (tagged RBC scan)
• MC location: splenic hilum
• MC organism associated with OPSI?
• S . pneumo
• Abdominal pain and CT with spleen in RLQ, abdominal U/S shows no flow in splenic vein. Diagnosis?
• Wandering spleen
• Caused by failure of fusion of dorsal mesogastrium, leading to lack of splenic ligaments
• Risk of splenic torsion and infarction
• Treatment?
• Splenectomy if splenic infarction, otherwise splenopexy
• MC source of post splenectomy bleeding?
• Short gastrics
• Patient with abdominal pain following splenectomy . CT shows large, low attenuation, contained fluid collection in surgical bed/lesser sac . Diagnosis?
• Pancreatic leak — tail of pancreas at risk during splenectomy
• Treatment?
• Percutaneous drain
• Patient with fever, hemolytic anemia, renal failure, purpura, neurologic changes . Diagnosis and management?
• Thrombotic thrombocytopenic purpura (TTP)
• FAT-RN mnemonic (Fever, Anemia, Thrombocytopenia, Renal, Neurological)
• Caused by defective ADAMTS13 metalloproteinase (vWF cleaving protein) → Platelet aggregation in microvasculature
• Treatment = Plasmapheresis

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