Small Ani. Sx- Spleen

drraythe's version from 2016-04-29 14:18

intro + total splenectomy + Partial splenectomy

Question Answer
where does the spleen sit in the body?orginates on the left side and then moves into the right side. It is adjacent to the greater curvature of the stomach and within the omentum.
what is this? this is Siderotic plaques or siderosis (not pathologic)
what are Siderotic plaques or siderosis? how bad is it?deposition of mineral (iron or calcium) on the surface of the spleen. considered a normal change with age in the dog - not related to neoplasia
5 main functions of the spleen?(1) Blood filtration and phagocytosis (2) Immune activities: blood-borne antg (3) Blood reservoir (RBC, platelets). (4) Stores Iron (5) Hematopoiesis
how might the spleen play a role in the maturation of RBCs?sometimes RBCs mature in the spleen before regular circulation
what are the indications for a total splenectomy? (5)(most to least common) (1) Primary neoplasm of spleen (2) Splenic torsion with vascular thrombosis (3) Severe trauma (4) Disseminated feline mastocytoma (cats, eosinophils) (5) Uncontrollable immune-mediated hemolytic anemia (hypersplenism)
can we live without the spleen?yes
reminder of circulatory anatomy of the spleenaorta-->celiac artery--> branches into three, the heaptic, pancreatic, and splenic artery. splenic artery enters into spleen at the hilus
things about surgical technique for splenectomyWide clipping, Large incision, Balfour retractors, Lab sponges, Use the palms (not fingertips spleen can be very friable), Assistant is helpful (relieve pressure on vena cava)
what are the two approaches to ligating vessels of the spleen for a total splenectomy?(1) Ligation of individual hilar vessels (2) Ligation of major splenic vessels (If ever in doubt go closer to the spleen, B/c the farther you start going own, you start compromising other blood supplies- Make sure you don’t double ligate vessels.)
what is a LDS 50 and how is it used? Ligating and Dividing Stapler with disposible cartridge. 1. Dissect vessels 2. Hook them 3. Pull trigger 4. It shoots 2 rows of staples and then the blade comes out and cuts. Can be used to ligate splenic vessels
what are possible complications of total splenectomy? (3)(1) Hemorrhage/bleeders (rupture) (2) Pancreatitis, pancreatic necrosis (vascular supply to pancreas is damaged) (3) Gastric necrosis (vascular supply to greater curvature of stomach is damaged)
what are consequences of total splenectomy? (5)(1) Increase in Howell-Jolly bodies, nucleated RBC (2) Increased platelet count (3) Decreased physical activity tolerance (4) Increases the chances of identifying subclinically infected animals (5) OPSI??? (overwhelming post-splenectomy infection )
what are howell jolly bodies and when do you see more of them?( blue bodies, remnants of nuclear material) Increased numbers are seen in splenectomized animals and regenerative anemia. Because there is loss of splenic filtration of RBC and morphological alterations of RBC in peripheral blood. After Newly released erythrocytes from the BM spend a few days in the spleen during maturation, « conditioning »before joinning the circulating pool.
why are there inc platelets after a total splenectomy?because of loss of platelet storage.(in immediate time after sx, it's bc spleen squeezed out all its blood and platelet storage before it was removed)
why is there Decreased physical activity tolerance after total splenectomy?spleen acts as blood reservoir for when we really need it
why does total splenectomy Increase the chances of identifying subclinically infected animals?Spleen plays a major role in removal of erythrocytes infected with hemoparasites or bacteria. Splenectomized dogs are thought to be more susceptible to infections like hemobartonella, Babesia and possibly other rickettsial infections. (so many infections are filtered out by or are hiding in spleen, so when spleen is gone, they are just out in general circulation)
how is prone to OPSI (Overwhelming Post Splenectomy Infection)?dobermans/GSD
why might there be OPSI (Overwhelming Post Splenectomy Infection)?(mostly in humans) spleen is the largest lymph organ in body. now lacking that defese barrier, so if get infections, it'll get a BAD infection. Need abx. Will see a high WBC count
what are the indications for a PARTIAL splenectomy? why do you want to do this? when DONT you want to do this?To preserve splenic function when part of the organ is destroyed or severely damaged. Indications are usually for injury (like penetrating trauma) or for focal abscesses. NOT INDICATED when suspected neoplasia--> if any doubt, take the spleen out.
what is the technique for a partial splenectomy?(more challanging than total!) large incision, balfour retractors, lap sponge.... then start by ligating area you want to remove. how do you know where to ligate and transect? ligate close to hilus, then WAIT A FEW MINUTES and then you will see a LINE OF DEMARKATION of what has and what doesnt have bleed supply. Then with you FINGERTIPS, CRUSH the tissue (gently). want to use fingers bc capsule will remain intact and that's a good thing. then place GI, hemostatic or vascular forceps along the proposed line of excision (make sure atraumatic on side that is staying), and then Use mattress sutures or staples through splenic parenchyma. Then can put simple continuous on capsule
If you are going to use stapler to do partial splenectomy.. what size staples and what determines this?35-55 mm staples, depending on the thickness of the spleen and if there was digital pressure applied at the staple site


Question Answer
what are the few ways to clinical assess splenomegaly? (4)(1) #1 thing you do- Abdominal palpation (2) Radiographs & ultrasound - size, position, density, visceral displacement (rads tell about size and position, US gives a little more info) (3) Laboratory evaluation - PCV,WBC, platelets (4) U/S guided FNA / Biopsy (PCR)
what kinda rads do you take for a case of splenomegaly, and why?abdominal AND thoracic (look for mets!!! esp in lungs!!)
asymmetrical splenomegaly can be due to.. (3)(1) Neoplasia (hemangiosarcoma /hemangioma!) (2) Benign splenic nodular hyperplasia (splenoma) (3) hematoma (hard to differentiate from hemangioma/sarcoma)
symmetrical splenomegaly can be due to.. (1) inc cellularity (Extramedullary hematopoiesis, Neoplasia (mast cell tumor in cats), Intravascular disease (vector borne dz: Ehrlichiosis) (2) Congestion (secondary to torsion and venous occlusion)
which neoplasia can result in SYMMETRICAL splenomegaly?mast cell tumor in cats
what are the 4 Primary Splenic Neoplasia?(1) Hemangiosarcoma (2) Hemangioma (3) Lymphoma/sarcoma (4) Fibrosarcoma (cats tend to get this one)
* what is the Most common malignant splenic neoplasm in dogs??Hemangiosarcoma!
what is the origin of hemangiosarcoma?Arises from vascular endothelium
is there age/breed/gender predelection of hemangiosarcoma?Older dogs (9 - 10 years), male dogs, especially German shepherds
hemangiosarcomas are super shitty because they metastasize where?Early metastasis to liver, omentum, lymph nodes, skin. Lungs later.
***what is a super common concurrent condition you often see with hemangiosarcoma? (Gimmie numbers)25% dogs with splenic hemangiosarcoma have concurrent cardiac hemangiosarcoma (so check for it!)
what are the clinical signs for hemangiosarcoma?Weakness, fatigue, Enlarged abdomen, Vague gastro-intestinal signs, Abdominal discomfort, Sudden collapse (rupture)
what are the radiographic signs of hemangiosarcoma?Cranial-ventral spherical mass, Displacement of viscera, Free fluid in cavity (hemoperitoneum)
perioperative considerations for hemangiosarcoma?Fluid replacement, Transfusion (do blood typing/matching before sx), CBC and chemistry, Coagulation profile
what are some side effects of splenectomy sx for hemangiosarc that you should warn anesthesia about?ventricular arrythmias (keep lidocaine handy!)
tx for hemangiosarc?splenectomy
what is prog for hemangiosarcoma? hemangioma?Hemangioma - guarded to good. Hemangiosarcoma - poor
what is Splenic Nodular Hyperplasia? who tends to get this? how does look? what is it's clinical sig?Incidental finding in Older dogs (> 8 years). It is a BENIGN neoplasia- Single or multiple small (0.5-3.0 cm or larger) nodules. No clinical significance except that it causes unnecessary splenectomy
ex of severe, moderate, and mild splenic injuries?Severe - deep lacerations, extensive crushing. Moderate - lacerations, vessel disruption. Mild - small hematomas (she didn't go through all the examples, just read over)
when should splenic trauma DEF be on your list?HBC
radiographic features of splenic injury? (3)(1) Loss of detail – hemoperitoneum (2) Visceral displacement – hematoma on spleen may be large (3) Small or irregular spleen (already totally bled out)
what are clinical findings like for splenic injury? (5) (and depend on what things?)(1) Depend on rate & volume of blood loss (2) Severe blood loss - hypovolemia, shock (3) Abdominal discomfort or enlargement (4) Laboratory findings may not reflect acute blood loss (5) May be incidental finding
what might indicate there was a past splenic trauma?omentum might be adhered (was acting as a bandage)
what is Splenosis?congenital or traumatic presence of multiple nodules of normal splenic tissue in the abdomen. Ectopic splenic tissue can arise from displacement of splenic tissue as a consequence of dysplastic fetal development. Alternatively, they result from past episode of splenic trauma which ruptures the capsule and seeds the peritoneum with spleen cells."
how do you go about Confirmation of hemorrhage if there is splenic trauma?Radiographs, Ultrasound, Abdominal paracentesis, Diagnostic Peritoneal Lavage
how do you treat splenic trauma?Blood or/and fluid replacement, Partial splenectomy or Total splenectomy (depends on if you can save some)
what is pathognomonic of splenic torsion on rads?C-shaped
what are examples of things that cause symmetrical splenomegaly due to CONGESTION?Secondary to torsion and venous occlusion, CHF, portal hypertension, Capsule relaxation
splenic torsion--> what is the spleen being torsioned around? which dog breeds are predisposed to this? etiology?Rotation on vascular pedicle, Large and giant breed dogs, male or female are prone to this. Etiology unknown
what problem happens because of splenic torsion? how does it present?Congestive splenomegaly as result of venous occlusion, sequestration of RBC’s. Can present as acute or subacute
Splenic Torsion--> ACUTE presentation--> Clinical findings?Physical discomfort, Salivation, gagging, retching, Tachycardia, tachypnea, Cardiovascular collapse, shock
DDX for Splenic Torsion: acute presentation? (7)(1)GDV (can be associated) (2) Rupture and hemorrhage from neoplasm (hemangiosarcoma) (3) Intestinal strangulation/mesenteric torsion (4) Pancreatitis (5) Peritonitis (6) Torsion of uterus or intra abdominal testicle (7) Poisoning
so, you should only untwist a splenic torsion if there are no thromosis. how can you tell if there is, though?feel the hilus/pedicle and if it feels like a sting a pearls, that is the thrombii (*remember to look for reperfusion injury if you untwist. gonna be a lot of free radicals-- untwist SLOWLY) (Of the drugs tested in experimental models, desferoxamine, an iron chelator, shows the most promise for clinical application)
what is the treatment for ACUTE splenic torsion?Cardiovascular resuscitation - treat for shock. Splenic repositioning - if no thrombosis seen in vessels of splenic pedicle (with care!). Splenectomy + gastropexy
Splenic Torsion--> SUB-ACUTE presentation--> Clinical findings? (4)(1) Vague abdominal discomfort (2) Lethargy, anorexia, occasional retching (3) Tachycardia, tachypnea, hyperthermia (4) Variable enlargement of abdomen
Splenic Torsion: sub-acute presentation TX? (2)(1) Splenic repositioning - if no thrombosis seen in vessels of splenic pedicle (2) Splenectomy + gastropexy