3. EMBRYOLOGY:
Development begins 3rd week of gestation .
Mature architecture 15 yrs of age .
5% of body weight in healthy neonate .
2% of body weight in adults .
Projection from ventral wall of midgut
Cranial bud – LIVER
Caudal bud – Gall bladder , Extrahepatic biliary tree
Ventral pancreas
4. ANATOMY:
2nd Largest organ , Largest gland .
Right upper quadrant of abdomen, just below diaphragm.
Weight –> Around 1400gm in females
1800gm in males .
Shape PRISM / WEDGE , BASE- Right
APEX- Left .
Pinkish brown colour , Soft in consistency , easily friable , highly
vascular .
Glisson’s capsule- Francis Glisson ,PATHOLOGIST .
5.
6. IHPBA TERMINOLOGY OF LIVER
ANATOMY:
Anatomically devided into larger right lobe and smaller left lobe by
FALCIFORM LIGAMENT.
Surgically devided into right and left lobes {60:40} by CANTLIES LINE
(gall badder fossa infront and IVC fossa behind). LOBAR ANATOMY
Its based on right and left branches of hepatic artery ,portal vein and
with tributaries of bile(hepatic) ducts.
MHV lies in CANTLIES LINE .
Left pedical [left hepatic artery, left branch of portal vein and left
hepatic duct] has longer extrahepatic course than right.
8. WHY…..?????
Three reasons why segmental resection is superior to simple wedge
resection.
1) Minimizes blood loss because vascular density is reduced at the
borders between segments.
2) It results in improved tumor removal for those cancers which are
disseminated via intrasegmental branches of the portal vein.
3)Spares normal liver allowing for repeat partial hepatectomy.
9. Each lobe is divided into 2 sectors.
The right hepatic vein (RHV) divides the right lobe into
anterior and posterior sectors; the left hepatic vein (LHV)
divides the left lobe into medial (quadrate) and lateral
sectors.
While the falciform ligament and umbilical fissure mark the
division between left lateral and left medial sectors on the
surface of the liver, no surface marking is observed
between right anterior and right posterior sectors.
The posterior sector of the right lobe and the caudate lobe
are not seen on a frontal view of the liver; the anterior
sector of the right lobe forms the right lateral border in
this view.
10. Caudate 'lobe' is not a lobe but a segment (I)
left lateral 'segment' is not a segment but a sector including two
segments (II and III).
&
11. BLOOD SUPPLY:
The liver has a unique dual blood supply (about 1500 mL/min) both from the proper
hepatic artery (20-40%) and from the portal vein (60-80%) .
PORTAL VEIN :
1-3cm diameter
5-8cm length
75% of hepatic blood flow
Laminar Blood flow
-Affects distribution of
amebic abscesses and
tumor metastases.
12. HEPATIC ARTERY :
Only 55-65% of population has “normal” hepatic arterial anatomy
Aberrant R hepatic artery may be mistaken for cystic artery
Cystic artery may originate from the gastroduodenal artery, the left
hepatic artery, or the common hepatic artery
13. VASCULAR SUPPLY:
25% of the cardiac output,
Average blood flow between 100 and 130 mL/minute per 100 g.
15. VENOUS DRAINAGE:
The three hepatic veins (RHV, MHV, and LHV) are largely intrahepatic
and lie on the posterior surface of the liver.
The MHV and the LHV may join to form a common trunk before
draining into the IVC. The IVC lies on the posterior surface of the liver
in a groove (or, sometimes, a tunnel) between the bare area on the
right, the caudate lobe on the left, and the caudate process in front.
• If thrombosis of the major hepatic veins occurs (Budd-Chiari
syndrome), the caudate veins become the key to drainage of
hepatic blood into the IVC. The caudate lobe is usually drained
by its own set of veins.
• In portal hypertension portosystemic shunts dilated.
19. NATURAL VARIENTS:
Anomalous right hepatic artery (RHA) from superior mesenteric artery (SMA)
• Anomalous left hepatic artery (LHA) from left gastric artery (LGA)
• Aberrant right posterior sectoral duct joining the left hepatic duct (can be
damaged during left hepatectomy)
• Aberrant right segmental, sectoral or even main hepatic duct joining the
common hepatic duct below the biliary ductal confluence in the Calot triangle
(can be injured during cholecystectomy)
22. HEPATIC BLOOD FLOW:
Total HBF : 1200-1700 ml/min
57.7 ml/100gm/min
25 % of CO
The time it takes for red blood cells to traverse from the portal vein
to the central vein is approximately 8–9 s, allowing sufficient time for
contact with hepatocytes and Kupffer cells.
32. HEPATIC FUNCTIONS:
Interface between abdominal viscera and systemic circulation
1. Energy Metabolism
2. Detoxification
3. Bile Production
4. Filtration of pathogens
5. Metabolism of vitamins, hormones, drugs, toxins, metals,
porphyrins
35. alpha-Fetoprotein
Fetal equivalent of albumin
Other transport/carrier proteins
Transferrin
Haptoglobin
Ferritin
Ceruloplasmin
All procoagulant factors except von Willebrand factor
37. RETICULOENDOTHELIAL SYSTEM :
Kuppfer Cells
Antigen Presenting Cells
Monocyte/Macrophage lineage
Clearance of particulate matter
Destroy microorganisms from alimentary tract
Clear old blood cells and cellular debris
Remove endotoxin
Cell-signaling function
Prostaglandin, interleukins, TNF, other cytokines
38. CLOTTING FACTORS-
Rapid turn over(factor VII has shortest half life : 2-6 hr)
Hence, best measure of acute hepatic dysfunction.
Prothrombin time is the best test
The PT, which is normally 11–14 s, measures the activity of
fibrinogen, prothrombin, and factors V, VII, and X.