Lecture 4: Surgery of the Spleen

What is enlargement of the spleen from any cause?

splenomegaly

What is splenectomy?

surgical removal of the spleen

What is congenital or traumatic presence of multiple nodules of normal splenic tissue in the abdomen?

splenosis

What are siderotic plaques?

brown or rust-colored deposits of iron and calcium on splenic surface

What is splenorrhaphy?

suturing of a ruptured spleen

What is this?

splenosis

What is this?

siderotic plaques

What is malignant neoplasm arising from blood vessels?

hemangiosarcoma

What are hemangiomas?

benign tumors of dilated blood vessels

What is a swelling or mass of blood (usually clotted) confined to an organ, tissue, or space caused by seepage of any reason?

hematoma

What are the indications for splenic surgery?

• Masses

• Loss of vascularity secondary torsion: GDV, splenic torsion

• trauma

• refractive immune-mediated hematologic disorders in some individual cases

True or false: Incidentally found, non-ruptured splenic masses or nodules without associated hemoperitoneum are most commonly benign.

true

What causes diffuse (symmetric) splenomegaly?

• Congestion (Torsion, GDV, Right-sided heart failure, Drugs)

• Infiltration due to infection (Fungal, Bacterial, Rickettsial)

• Splenic foreign body

• Immune mediated disease (IMHA, IM Thrombocytopenia)

• Neoplasia (Lymphosarcoma, Histiocytic sarcoma, Feline mastocytosis)

What are the causes of focal (asymmetric) splenomegaly?

• Benign processes (Nodular regeneration, Hematoma, Trauma)

• Neoplastic processes (Hemangiosarcoma = HSA)

What is one of the most common causes of spontaneous splenomegaly in dogs and cats?

infiltrative splenomegaly from neoplasia

What is splenic torsion most often associated with?

GDV

What happens with splenic torsion?

• splenic vein becomes occluded

• splenic artery is partially blocked (infarction)

• splenomegaly

• acute or intermittent signs for weeks

What downstream effects are splenic torsion associated wtih?

cardiovascular collapse and shock, increased likelihood of GDV, septicemia from massive bacterial overgrowth in the necrotic splenic tissue, and hemoabdomen

What may be warranted after splenic torsion because of stretching of gastric ligaments resulting in the increased likelihood of GDV?

prophylactic gastropexy with spenectomy

True or false: it is widely accepted that the absence of a spleen to act as a counterbalance to gastric torsions may warrant a prophylactic gastropexy.

false: research has called this practice into question when splenectomy was not related to a GDV or splenic torsion

What is the most common splenic tumor in dogs and the most common malignant splenic tumor in cats?

hemangiosarcoma

Why is an echocardiogram in non-emergent splenectomy to remove a splenic mass warranted in dogs?

as many as 25% of dogs with splenic HSA may have concurrent right atrial HSA

Where does splenic hemangiosarcoma frequently metastasizing?

• liver

• omentum

• mesentery

• brain

True or false: splenic hematomas and hemangiomas are grossly indistinguishable from hemangiosarcomas, so you should let your pathologist make the call.

true

What should be assessed during pre-op management for a splenectomy?

• anemia (acute hemorrhage with trauma, rupture of hematoma, underlying disease)

• coagulation profiles if trauma not suspected as cause of hemorrhage

• consider for blood transfusion

• assess for hydration

• assess for DIC

When do anemic patients need O2?

prior to induction and during recovery

What drugs should be avoided during splenectomies and why?

• barbiturates: cause splenic congestion

• acetylpromazine: red blood cell sequestration, hypotension, impact on platelet function

What is this tool?

ligating dividing stapler

What is this device?

TIA stapler: transverse intestinal stapler

What is the arterial supply of the spleen?

splenic artery, a branch of the celiac artery

Why must you identify the pancreas during a splenectomy?

the first branch of vasculature is usually to the left limb of the pancreas and is its main arterial blood supply → you must identify the pancreatic supply coming off the splenic artery and ligate the splenic artery distal to it

What incision is made for a splenectomy?

ventral midline approach from a xyphoid to a point caudal to the umbilicus (longer for large lesions or complete exploratory for neoplasia)

When is a partial splenectomy indicated?

with trauma or focal lesions to preserve splenic function

What does a total splenectomy result in the loss of?

all splenic function:

• RBC reservoir

• hematopoiesis

• important phagocytic function

• help with immunocompetence

When is a total splenectomy contraindicated?

bone marrow hypoplasia

What are the major techniques of total splenectomies?

1. Ligation at splenic hilus

2. Splenic artery ligation

3. Bag Of Rochester Carmalts

4. Laparoscopic

What post-op care and assessment is necessary after a splenectomy?

• 24 hour observation for hemorrhage and hematocrit every few hours until stable

• nasal O2 for anemic patients

• fluid therapy

• electrolyte and acid-base correction

• monitor for cardiac arrhythmias

• monitor for DIC

• antibiotics after 24 hours if warranted & pain management

What are the commonly seen complications with splenectomies?

• hemorrhage (more of an issue with biopsies or partial splenectomy)

• traumatic pancreatitis

• gastric fistulation due to impairment of gastric blood flow

• previous infection with hemoparasites may become apparent after splenectomy