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Surgery

Spleen

Dr. Muayad Abass Fadhel

Lec. 21

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

1Oth rib



There is a

notch on its inferolateral border

, and this may be palpated

when the spleen is enlarged.

Blood supply:



The tortuous splenic artery

arises from the

coeliac axis

and runs along

the upper border of the body and tail of the pancreas,to which it gives
small branches.



The

short gastric

and

left gastroepiplolc branches

pass between the

layers of the

gastrosplenic ligament



The

main splenic artery

generally divides into

superior and inferior

branches, which, in turn, subdivide into

several segmental branches.

Surgery

Spleen

Dr. Muayad Abass Fadhel

Lec. 21

Venous drainage:



The

splenic vein

is formed from several tributaries draining the hilum.



The vein runs behind the pancreas, receiving several small tributaries
from the pancreas before joining the

superior mesenteric vein at the

neck of the pancreas to form the portal vein.

The lymphatic drainage:



The lymphatic drainage comprises efferent vessels in the white pulp that

run with the arterioles and emerge from nodes at the hilum.



These nodes and lymphatics drain via retropancreatic nodes to the

coeliac nodes.

FUNCTIONS OF THE Spleen



Although the spleen was previously thought to be dispensable,

increasing knowledge of its function has led to a conservative approach
in the management of conditions involving the spleen'



The surgeon normally should Endeavour to preserve the spleen to

maintain the following function:

Immune function

The spleen processes foreign antigens and is the major site of specific
immunoglobulin M (lgM) production.

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.

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 is less marked than in other species,but the spleen does
contain approximately 8 % of the red cell mass.An enlarged spleen may
contain a much larger proportion of the blood volume.

Surgery

Spleen

Dr. Muayad Abass Fadhel

Lec. 21

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

Investigation:

A- Laboratory examination



SPLENOMEGALY with

haemolytic anaemia

a full blood count,

reticulocyte count and tests for haemolysis will determine the cause
of the anaemia.



Splenomegaly associated with portal hypertension caused by

cirrhosis is diagnosed on the history, physical signs of liver
dysfunction, and abnormal tests of liver function and endoscopic
evidence of oesophageal varices.



Splenomegaly are associated with lymphadenopathy investigation

should be directed at those disease processes known to be
associated with both physical signs. Lymph node biopsy may be
required.

B- Radiological imaging:



plain radiology:

Calcification

of the splenic artery or spleen may rise the diagnosis of

splenic artery aneurysm

old infarct

benign cyst or hydatid cyst.

Multiple area of calcification

may suggest tuberculosis of the

spleen.



ultrasonography:

Determine the

size and consistency

of the spleen and whether the

cysts

are presents



Computed tomography scan: with contrast enhancement is better to

charectarize the nature of splenic pathology and to exclude other
intraabdominal pathology.



magnetic resonant image scan similarly useful



Radioisotope scan sometimes used to give information about the

spleen.

Surgery

Spleen

Dr. Muayad Abass Fadhel

Lec. 21



Technetium 99 labelled colloid

Is restricted to determine whether the spleen

is the site of red blood

cell destruction.

Splenic artery aneurysm



Aneurysms involving the splenic artery are estimated to occur

0.04%

of post-mortem examinations.



It is common in the

female

and are usually situated in the

main

arterial trunk.



It may result as a consequence of

intra-abdominal sepsis

and

pancreatic necrosis



They are more likely to be associated with

arteriosclerosis in elderly

patients.



The aneurysm is

symptomless unless it ruptures



It is

unlikely to be palpable

, although a

bruit may be present



half of the cases

of rupture occur in patients

younger than 45 years

old,



And quarter

is in pregnant women

, usually in the third trimester of

pregnancy or at labour.



The treatment of choice is

splenectomy and removal of the diseased

artery.



Embolisation following selective splenic artery angiography

can be

considered in the unfit patient.



In the

younger patient with an asymptomatic splenic artery

aneurysm, surgery is indicated after CT scan, MRI or selective
coeliac angiography has confirmed the diagnosis.



.In the

elderly patient with a calcified aneurysm

, there is

less risk of

rupture and observation

may be preferred.

Splenic rupture



-Splenic rupture should be considered in any case

of blunt abdominal

trauma

, particularly when the injury occurs to the

left upper quadrant

of the abdomen



Splenic injury should be considered if there are

fractures of the

overlying ribs.

Surgery

Spleen

Dr. Muayad Abass Fadhel

Lec. 21



Iatrogenic injury to the spleen remains a frequent complication of any
surgical procedure

, particularly those in the left upper quadrant when

adhesions are present

Ruptured spleen may present in three ways:
1-

The patient succumb rapidly from massive hemmorrage

as a consequence of

trauma or slippage of a pedicle suture

may lead to

rapid exsanguination.
2-

Initial shock, recovery,signs of late bleeding

The initial shock is due to blood loss, tamponade occurs and then further
bleeding.



General signs of internal haemorrhage may be variable but local
signs include

left upper quadrant guarding and tenderness,

followed

abdominal distension.

Kehr's sign:



The referral of pain to the left shoulder can be demonstrated some

15 minutes following elevation of the foot of the bed.



The pain results from the contact of blood with the undersurface of

the diaphragm and is mediated through afferent fibres of the phrenic
nerve.



Shifting dullness

may be present in the flanks and

fullness in the

pelvis may be evident on rectal examination.



Abdominal ultrasonography or CT scanning will demonstrate the

source of the bleeding in the patient who is stable enough to
undergo imaging before urgent laparotomy.

The delayed case:



The initial signs of splenic injury may

pass quickly or not be

recognised but delayed rupture can occur after few days.

Management:



The ruptured spleen can be

managed successfully without operation.



Careful observation

can be pursued in the patient

with minimal or no

abdominal findings

and when there is

haemodynamic stability .

Surgery

Spleen

Dr. Muayad Abass Fadhel

Lec. 21



CT may confirm isolated injury to the spleen and a conservative

approach should be considered in the absence of hilar involvement or
massive disruption of the spleen.

Immediate laparotomy

is indicated for splenic trauma if



there is obvious evidence of continuing blood loss despite adequate

resuscitation



laparotomy should be considered if there is a strong suspicion of

trauma to other organs.The treatment of associated injuries is
dictated by the operative findings.



Splenic preservation

should be considered where possible



Minor capsular parenchymal injuries may require only topical

haemostatic agents.



If by careful compression of the spleen the bleeding can be

controlled, suture of the injury with or without application of
haemostatic agents may be useful.



Parenchymal injuries involving the lower or upper pole of the spleen

may be managed by partial segmental resection.

Splenomegaly:

Common feature of many disease processes



A-infective

Bacterial

1.  Typhoid and  paratyphoid
2.  Typhus
3.  Tuberculosis'
4.  Septicemia
5.  Splenic  abscess
6.  Spirochoeta         Weils disease
7.  Syphilis

Viral

1.  infectious mononucleosis
2.  HIV-related
3.  Protozoal and parasitic
4.  Malaria
5.  Schislosomiosis'

Surgery

Spleen

Dr. Muayad Abass Fadhel

Lec. 21

6.  Trypanosomiasis
7.  Kalazar
8.  Hydatid cyst



B-Blood disease

1.  Acute leukaemia
2.  ldiopathic thrombocytopenic purpura
3.  Chronic leukaemia
4.  Perniciouose anemia
5.  Hereditory spherocytosis
6.  Autoimmune hemolytic anemia
7.  Polycythemia vera
8.  thalassemia
9.  Erythroblastosis fetalis
10.

sickle cell anemia



C- Metabolic

1.  Rickets
2.  Amyloid
3.  Porphyria
4.  Gaucher's disease



D- Circulatory

1.  lnfarction
2.  Portal hypertension
3.  Segmental portal hypertension (pancreatic    carcinoma,splenic vein

thrombosis)



E-Collagen disease still disease

Felty syndrome



F-Non parasitic cysts congenital

Acquired



G-Neoplastic Angioma

                                    Primary   fibrosarcoma
                                    Hodgkin's lym phoma
                                    other lymphomas
                                     Myelofibrosis

Surgery

Spleen

Dr. Muayad Abass Fadhel

Lec. 21

Hypersplenism:



Is an indefinite clinical syndrome that is charectarized by

splenic

enlargement

,any combination of

anemia,leucopenia or

thrombocytopenia

,compensatory

bone marrow hyperplasia

and

improvement after splenectomy

Splenic abscess



Splenic abscess may arise from an

infected splenic embolus

in association with

typhoid and paratyphoid fever

osteomyelitis, otitis

media

and

puerperal sepsis



It may be associated with

pancreatic necrosis or other intra'

abdominal infection.



An abscess

may rupture

and form a

left subphrenic abscess

or result

peritonitis



The treatment involves that of the

underlying cause

and drainage of

the

splenic abscess by percutaneous

means under radiological

guide.

Neoplasm:



Haemangioma :

is the

most common benign tumour

of the spleen and may develop rarely

into a haemangiosarcoma that is managed by splenectomy.



Lymphoma:

is the

most common cause of neoplastic enlargement

, and splenectomy

may play a part in its management.
Splenectomy may be required to

achieve a diagnosis

in the absence of

palpable lymph nodes or to

relieve the symptoms

of gross splenomegaly.



Myelofibrosis:

Is due to an

abnormal proliferation of mesenchymal elements in the bone

marrow

spleen

liver and lymph nodes

Most patients present over the age of 50 years and the spleen may
produce pain owing to its gross enlargement or from splenic infarcts,
Splenectomy reduces the need for transfusion and may relieve the
discomfort resulting from the splenomegaly

The spleen is rarely the site of metastatic disease.

Surgery

Spleen

Dr. Muayad Abass Fadhel

Lec. 21

Splenectomy

-open splenectomy:
- laparoscopic splenectomy

Indication:

Trauma

resulting from an

accident

during a surgical procedure

, as for

example during mobilisation of the oesophagus, stomach, distal pancreas
or splenic flexure of the colon.

2-

Removal enbloc with the stomach

as part of a

radical gastrectomy

or with

the

pancreas as part of a distal or total pancreatectomy

3- To reduce

anaemia

thrombocytopenia

spherocytosis

idiopathic thrombocytopenic purpura

hypersplenism.

4-In association with

shunt or variceal surgery

for

portal hypertension.

Preoperative preparation:



In the presence o f a bleeding tendency, transfusion of blood,fresh-

frozen plasma, cryoprecipitate or platelets may be required.



Antibiotic prophylaxis appropriate to the operative procedure Should

be given and considirartion given to the risk of postsplenectorny
Sepsis.

Postoperative complications

Immediate complications

hemorrhage

resulting from the

slipped ligature of splenic artery

Haematemesis

from gastric mucosal damage and gastric dilatation.

left basal atelactesis

and

pleural effusion

adjacent structure injury like stomach and pancrease

. Aflistula may result

from damage to the greater curvuture of the stomach during ligation of the
short gastric vessels. Damage to the tail of the pancreas may result in
pancreatitis, localized abscess or a pancreatic fistula.
5- The blood platelet count may Rise in number resulting in axillary and
other venous thrombosis. Aspirine is indicated

Surgery

Spleen

Dr. Muayad Abass Fadhel

Lec. 21

Post-splenectomy septicaemia:



may result from

Streptococcus pneumonia

Neisseria meningitides

Haemophilus influenzae

and

Escherichia coli



The risk is greater in

young patient

-Splectomized patient

treated with chemoradiotherapy

-Patient undergo splenectomy for

thalassemia,sickle cell

anemia and autoimmune anemia.

Opportunistic postsplenectomy infection(OPSI):



children who have undergone splenectomy before the age of five

years should be treated with daily dose of pencillen until the age of 10
years.



The risk of this overwhelming infection is more within the fist 2-3

years of splenectomy.



Satisfactory oral prophylaxis can be obtained with penicillin,

erythromycin or amoxicillin or co-amoxiclav.



Suspected infection can be treated intravenously with these same

antibiotics and cefotaxime, ceftriaxone or chloramphenicol in patients
allergic to penicillin and cephalosporins.



If elective splenectomy is planned, consideration should be given to

vaccinating

against pneumococcus, H. influenzae and

meningococcus.



Pneumococcal vaccinatictn

is recommended in those patients aged

over 2 years



Haemophilus influenzae

vaccination is recommended

irrespective of

age



Meningococcal vaccination

is not recommended routinely unless the

individual is considering travel to areas where there is a risk of
infection, in local outbreaks and for contacts with infected cases.



It is also recommended that

influenza vaccine

be given to asplenic

patients as influenza has been implicated as a risk factor

for

secondary bacterial infection



In the

trauma victim

, vaccination can be given in the post' operative

period and the resulting antibody levels will be protective in the
majority of cases.



Antibody levels are, however

, less than 50% of those achieved if

vaccination is given in the presence of an intact spleen