DR.SYED UBAID M.S(KEM MUMBAI) FMAS LAPAROSCOPIC AND GENERAL SURGEON ASSOCIATE PROFESSOR OF SURGERY IIMSR,JALNA
SPLEEN
Galen –source of black “black bile’ or “melancholia”
Anatomy Largest reticuloendothelial organ Mesodermal in origin Spleen size & weight diminish in the elderly Splenomegaly – apply to weight > 500mg and/or 15cm or more in length. If palpable below the left costal margin ---> double normal size
Anatomy The weight of the normal adult spleen is 75–250 g. It lies in the left hypochondrium between the gastric fundus and the left hemidiaphragm , with its long axis lying along the tenth rib. There is a notch on the inferolateral border, and this may be palpated when the spleen is enlarged.
Anatomy Blood Supply: Splenic artery (pattern of terminal branches) Distributed type: (70%) Short trunk w/ many long branches over ¾ of the medial surface of the spleen. Magistral type: (30%) Long main trunk dividing near the hilum into short terminal branches. Short gastric artery:
Anatomy Support of the spleen: Splenocolic lig. Gastrosplenic lig. (short gastric vessels) Phrenosplenic lig. Splenorenal lig.
Anatomy Microstructure of the spleen: Red pulp (75%): Large numbers of venous sinuses that drains into splenic veins Sinuses is surrounded & separated by reticulum where the macrophages lies. Serves as a dynamic filtration system where macrophages remove the microorganisms, cellular debris, Ag & Ab complexes and senescent erythrocytes. White pulp: Periarticular lymphatic sheaths Comprised T lymphocytes and intermittent aggregations of B lymphocytes or lymphoid follicles.
FUNCTIONS Immune function Filtration Pitting Storage Cytopoiesis
Immune function. The spleen processes foreign antigens and is the major site of specific immunoglobulin M ( IgM ) production. The non- specific opsonins , properdin and tuftsin , are synthesised . These antibodies are of B- and T-cell origin and bind to the specific receptors on the surface of macrophages and leukocytes, stimulating their phagocytic , bactericidal and tumoricidal activity.
Filter function Macrophages in the reticulum capture cellular and non-cellular material from the blood and plasma. This will include the removal of effete platelets and red blood cells. Iron is removed from the degraded haemoglobin during red cell breakdown and is returned to the plasma. Removed non-cellular material may include bacteria and, in particular, pneumococci .
Pitting. Particulate inclusions from red cells are removed, and the repaired red cells are returned to the circulation. These include Howell–Jolly and Heinz bodies, which represent nuclear remnants and precipitated haemoglobin or globin subunits, respectively.
Reservoir function This function in humans is less marked than in other species, but the spleen does contain approximately 8 per cent of the red cell mass. An enlarged spleen may contain a much larger proportion of the blood volume.
Cytopoiesis From the fourth month of intrauterine life, some degree of haemopoiesis occurs in the fetal spleen. Stimulation of the white pulp may occur following antigenic challenge, resulting in the proliferation of T and B cells and macrophages. This may also occur in myeloproliferative disorders, thalassaemias and chronic haemolytic anaemias
Congenital abnormality The most common anomaly of splenic embryology is the accessory spleen. 80% in the splenic hilum and vascular pedicle gastrocolic lig. tail of pancreas greater omentum greater curve of the stomach splenocolic lig. small & large bowel mesentery left broad lig in women left spermatic cord in men.
differences Sharp edge Notch –med border Cross midline Moves with respiration Cannot get above it Round edge No notch Not cross midline Not moves with resp. Can get above it spleen kidney
splenomegaly Mild,moderate,massive Massive - beyond umblicus , crosses mid line into pelvis (>8cm) Moderate - b/w costal margin & umblicus (4-8cm) Mild - just palpable (1-3cm)
hyperslenism Splenomegaly Pancytopenia Presence of hypercellular marrow Reversal with splenectomy
Symptoms of splenomegaly Pain Early satiety Feeling of heaviness in LUQ
Mechanism of spenomegaly Reactive Reticulo -endothelial hyperplasia Lymphoid hyperplasia Proliferation of lymphoma cells Infiltration by abnormal cells Extramedullary hemopoeisis Proliferation of macrophages d/t RBC destruction Vascular congestion
Causes of splenomegaly Infective Hyperplastic Congestive Infiltration
Tropical splenomegaly ( hms ) Massive splenomegaly Endemic areas of malaria,kala-azar IgM antibodies + No parasite in blood Lymhocytic infiltration of splenic sinusoids Long term anti- malarials
Indications for Splenectomy Most common indication is trauma to spleen , whether iatrogenic or otherwise Most common elective splenectomy is ITP followed by hereditary spherocytosis ----> autoimmune hemolytic anemia -----> thrombotic thrombocytopenic purpura .
Splenectomy for Hematologic Diseases Rarely cures the disease Alleviates symptoms Corrects hematologic abnormalities Staging & Diagnosis
Splenectomy for Hematologic Diseases Red Cell-Related Indications Hereditary Spherocytosis (HS) Most common type of hemolytic anemia Autosomal dominant Spectrin deficiency (RBC membrane) → Loss of osmotic stability Osmotic fragility testing Splenomegaly & Gall stones Dx by (+) spherocytes in the blood TOC is Splenectomy in the 4 th year of life +/- cholecystectomy if (+) cholelithiasis
Splenectomy for Hematologic Diseases Autoimmune Hemolytic Anemia (AIHA) Warm-antibody autoimmune HA Autoantibody opsonization and phagocytosis Intravascular destruction or by spleen macrophages Treatment Of Choice #1 is Corticosteroids 1-2 mg/kg/day PRBC’s for severe anemia Splenectomy (80% favorable clinical response) if: medical tx fails Intolerance to steroids or its side-effects
Splenectomy for Hematologic Diseases Pyruvate kinase Deficiency Autosomal-recessive disease Splenomegaly TOC Splenectomy Reduces PRBC’s requirements G6PD Deficiency Splenomegaly is rare Splenectomy is not indicated!
Splenectomy for Hematologic Diseases Sickle Cell Disease (SCD) B-globin gene A → T substitution (Hb S/SS) autosomal dominant Sickling of RBCs in tissues with low O 2 tension Red & White pulps Splenic microinfarcts Painful Abscess Infections Anemia Splenectomy (palliative) Acute sequestration crises (recurrence = 40%-50% with 20% Mortality rate) Rapid hypersplenism Abscess formation
Splenectomy for Hematologic Diseases Thalassemia Thalassemia major (homozygous B) autosomal-dominant disease Decreased expression of beta-chains Pallor, Growth retardation, head enlargement Splenectomy indicated if: Symptomatic splenomegaly Anemia Pain due to infarctions increased PRBC’s requirements (>200 ml/kg/year) ↑ rate of infections after splenectomy Risk vs. Benefit
Splenectomy for Hematologic Diseases Platelet Related Indications ITP Spleen is not enlarged ♀ > ♂ ; Renal insufficiency children vs. adults Self-limited in children (70%) Splenectomy is for rare cases Insidious onset in adults ↓ Plts < 10,000/mm 3 #1 TOC is PO Steroids 1-1.5 mg/kg/d (up to 70% response) IVIG 1 g/kg/d x2-3 days Splenectomy if fail steroid tx TTP Splenomegaly Microvascular thrombosis Petechiae, fever, neurologic changes #1 TOC Plasmaphoresis Splenectomy is #2 Durable remission? Avoid PLT transfusions ↑ morbidity
White Cell - Related Indications Leukemia CLL & Hairy cell leukemia (HCL) Splenectomy improves cytopenias (75%) Ameliorates symptomatic splenomegaly Non-Hodgkin’s Lymphoma (NHL) Splenectomy Painful splenomegaly Cytopenia No role for staging
White Cell - Related Indications Hodgkin’s Disease Current indications for surgical staging: Stage I or Stage II with NS histology and w/o B-symptoms Staging procedure Wedge liver biopsy LN sampling: Retroperitoneal Mesenteric Hepatoduodenal Splenectomy
Bone Marrow – Related Indications Myelofibrosis & Myeloproliferative disorders Splenectomy for symptoms due to enlarged spleen
Preoperative Considerations Splenic artery embolizations: Recommended for: Massive splenomegaly Previous pancreatitis, gastric or pancreatic surgery Portal hypertension, varices Uncorrectable thrombocytopenia
Preoperative Considerations Splenic artery embolizations: Advantages: Reduced operative blood loss from devascularized spleen Reduces spleen size for easier dissection and removal. Disadvantages: Acute left sided pain (limited duration) This is mitigated by general anesthesia ---> OR pancreatitis Currently no consensus
Preoperative Considerations Vaccination: Splenectomy imparts <1 to 5% fulminant infection (overwhelming post-splenectomy infections) Vaccination against encapsulated bacteria 2 wks before surgery.
Preoperative Considerations Vaccination: Common bacteria: Streptococcus pneumoniae Hemophilus influenzae type B Meningococcus Grp A streptococcus Capnocytophaga canimorsus (related to dog bites) Grp B streptococcus Enterococcus sp. Bacteroides sp. Salmonella sp. Bartonella sp.
Preoperative Considerations Vaccination: in emergency splenectomy, trauma, give vaccine 3 rd day booster injections every 5 – 6 yrs regardless of the reason for splenectomy for pneumococcal annual influenza immunization
Preoperative Considerations Deep venous Thrombosis Prophylaxis: Specially in splenectomy for myeloproliferative disorders (MPD). 40% risk for PVT (portal vein thrombosis) Anorexia Abdominal pain Leukocytosis & thrombocytosis Early diagnosis w/ contrast-enhanced CT scan Anticoagulation ---> keys for successful tx Prophylaxis: --> subcutaneous heparin (5000U)
Preoperative Considerations Deep venous Thrombosis Prophylaxis: Risk factors: Obesity History of venous thromboembolism Known hypercoagulable state > 60y/o
SPLENECTOMY Preparations: polyvalent pneumococcal, meningococcal & haemophilus vaccines 1 wk. preop. check hgb and coagulation status of pt. (at least 10g/dl) 2 to 4 units of cross-matched bld. available at time of surgery. platelet transfusion (thrombocytopenia) started right after ligation of splenic artery.
SPLENECTOMY Preparations: pt. on corticosteroid therapy shd. receive it parenteraly deep vein thrombosis prophylaxis 1 st generation cephalosporin IV as brought to the OR. NGT to decompress the stomach after placing the endotracheal tube.
SPLENECTOMY Open Splenectomy: Indication: traumatic rupture of the spleen (most common) massive splenomegaly ascites portal hypertension multiple prior operations extensive splenic radiations possible splenic abscess
SPLENECTOMY Open Splenectomy: Position: Supine: midline incision for rupture or massive splenomegaly or for staging Hodgkin’s dse. Left subcostal incision – for elective splenectomies
SPLENECTOMY Laparoscopic Splenectomy: for normal size spleens Position: supine or low lithotomy position (needs 5-6 trocars) Right lateral decubitus (needs 3-4 trocars) Excised spleen placed in a durable nylon sac and is morcellated and extracted piecemeal using a blunt instrument avoiding splillage ----> splenosis.
Partial Splenectomy Indicated: children (risk of splenectomy sepsis) Lipid storage disorders (Gaucher’s dse) Some blunt & penetrating splenic injuries open or laparoscopically Bleeding from cut surface of the spleen is controlled by: cauterization argon coagulation application of hemostatic agents (cellulose gauze / fibrin glue)
Changes in blood after splenectomies Appearance of Howell-Jolly bodies & siderocytes Leukocytosis Increased platelet counts
Complications of Splenectomies Pulmonary complications: Left lower lobe atelectasis (most common) Pleural effusion Pneumonia Hemorrhage ----->subphrenic hematoma Infectious complication: Subphrenic abscess (due to placement of drains, hence not routinely recommended)
Complications of Splenectomies Pancreatic complications : due to intra-op trauma to tail of pancreas Pancreatitis Pseudocyts Pancreatic fistula Thromboembolic phenomena (5-10%) For pt. w/ hemolytic anemia / myeloproliferative disorders and splenomegaly Subcutaneous heparin & low-dose anticoagulantion therapy postop
Complications of Splenectomies Overwhelming Postsplenectomy Infection (OPS): lifetime risk of severe infection (1-5%) incidence similar among children & adult but mortality is higher in children. mortality is highest in hematologic conditions: Thalaseemia major Sickle cell dse lowered due to pneumococcal vaccine
Complications of Splenectomies Overwhelming Postsplenectomy Infection (OPS): Loss the ability to filter and phagocytose bacteria and parasitized bld cells ----> infection to encapsulated bacteria or parasites Loss a significant source of antibody production: Streptococcus pneumoniae (most common infection 50-90%) Haemophilus influenzae type B Meningococcus Grp A streptococcus