Hepatectomy

Hepatectomy
Dr. Sana Aboosalih

Anatomy
Two anatomic lobes separated on the anterior
surface of the liver by the falciform ligament
and on the inferior surface by the ligamentum
teres as it enters the umbilical fissure.
invested by peritoneum except on its posterior
surface where the peritoneum reflects to
create the right and left triangular ligaments.
The area between the folds of peritoneum that
create the triangular ligaments is devoid of
Peritoneum and is referred to as the bare area.
The retrohepatic inferior vena cava (IVC) lies
within
this bare area on the undersurface of the liver.

Functional surgical anatomy
Couinaud segments
Understanding the internal anatomy of the liver
is essential to performing hepatic resections
and, in particular, parenchymal-preserving
resections.
the three main hepatic veins separate the liver
into four sectors, 7 segments, each of which is
fed by a portal pedicle that includes a branch of
the hepatic artery, portal vein and bile duct.
The right and left hemilivers are divided by the
main portal scissura, which contains the middle
hepatic vein.

• Both the right and left hemilivers are further divided into sectors by scissurae
containing the right and left hepatic veins.
• The right portal scissura separates the right liver into the anterior and the
posterior sectors.
• The right anterior sector is comprised of segments V inferiorly and VIII superiorly, and the
right posterior sector is comprised of segments VI inferiorly and VII superiorly.
• The left portal scissura, which runs to the left of and posterior to the ligamentum teres along
the course of the left hepatic vein, separates the left liver into the anterior and posterior
sectors.
• Segment IV can further be divided into segment IVA superiorly and segment IVB inferiorly
based on the branching of the left portal pedicle
• The caudate lobe (segment I) is the portion of liver that lies between the IVC
and the main portal pedicle and straddles the retrohepatic IVC.
• It is supplied by vessels from both the right and left portal pedicles, and
biliary drainage follows a similar pattern.
• The caudate lobe is the only portion of the liver that drains directly into the
IVC.

Brisbane terminology
• An alternative nomenclature was devised by the Scientific Committee of the
International Hepato-Pancreato-Biliary Association (IHPBA) in Brisbane, Australia, in
2000.
• This terminology was created in an attempt to clarify the confusion surrounding the
terminology of liver anatomy and resections.
• The main difference between Couinaud’s description and the Brisbane 2000
Terminology is the renaming of Couinaud’s sectors as sections.
• Left liver is not divided into 2 sectors based on the left hepatic vein. The left liver is
defined as having a lateral section (segments II and III) and a medial section (segment
IV). [Based on the division of the left liver by the line between the falciform ligament
and the umbilical fissure]

Surgical Implication
• All methods for precise partial hepatectomy depend on control of the
inflow vasculature and draining bile ducts and the outflow hepatic
veins of the portion of liver to be excised, which may be a segment, a
subsegment, or an entire lobe.
• The remnant remaining after partial hepatectomy must be provided
with an excellent portal venous inflow, hepatic arterial supply, and
biliary drainage and unimpeded hepatic venous outflow.

Classification
• Major hepatic resection are defined as the resection of three or more
liver segments based on Couinaud classification
• The aforementioned nomenclature was introduced by the
International Hepato-Pancreato-Biliary Association in the Brisbane
2000 Nomenclature of Hepatic Anatomy and Resections in an effort
to accurately describe the hepatic anatomy and standardize the
terminology in the field.

There are three major risks of hepatic resection:
(1) hemorrhage, which may arise at the porta hepatis from
branches of the hepatic artery or portal vein, intrahepatically
from hepatic veins, or posteriorly from hepatic venous
radicles or the IVC
(2) biliary fistula or stricture as a result of damage to the
biliary apparatus
(3) postoperative liver insufficiency or failure.

Preoperative considerations - INVESTIGATIONS
• CT scanning - extent of disease and degree
of vascular compromise.
• Vascular invasion: CT Angiographic study
rarely required.
• MRI - demonstration of the major hepatic
veins and vena cava and their relationship
to tumor masses.
• Ultrasound –
• providing information on the size of the
tumor and extent of liver involvement.
• distinguish cysts from solid tumors,
• duplex US demonstrates tumor location
with respect to important vascular
structures, including the hepatic veins
and vena cava.
• particular importance in the
preoperative evaluation of hilar
cholangiocarcinoma by defining the
extent of involvement of the portal vein
and hepatic artery
• If preoperative biliary drainage is necessary,
direct cholangiography, either endoscopic
or percutaneous, will be required.
• Preoperative biopsy should be pursued
only if the information gained will alter the
treatment plan.

Preoperative considerations - Staging Laparoscopy
• Laparoscopic exploration and visualization, in combination with
laparoscopic US – provide information regarding the presence of additional
lesions not appreciated on preoperative imaging.
• Reveal the presence of extrahepatic disease, particularly peritoneal
dissemination.
• By minimizing unnecessary laparotomy, this approach has been shown to
increase the resectability rate of patients submitted to laparotomy.
• In one study at MSKCC, 83% of patients subjected to laparotomy after lapa-
roscopy underwent potentially curative resection, compared with only 66%
of patients not staged laparoscopically (Jarnagin et al, 2000)

Resectability is not defined only
by what can be removed, but
more by what can be left behind

Preoperative considerations –
Assesment of RESECTABILITY
• liver remnant should be of sufficient quantity and quality, with adequate inflow, outflow,
and biliary drainage to sustain the patient’s life in the postoperative period and for the
duration of hepatic regeneration.
• Major difficulties with accurate preoperative assessment of resectability can arise in two
situations:
• First, tumors situated near the major hilar structures or those greatly compressing or
involving the vena cava can be difficult to assess preoperatively.
• Second, very large tumors, which push structures aside and have been slowly
growing during a long time, are difficult to define precisely, because pressure
changes may mimic invasion on radiologic images.
• Thus considerable caution must be exercised before declaring a case unresectable.

Future liver Remanent - FLR
• The volume of the FLR needed to minimize the chances of postoperative liver insufficiency varies
according to the quality of the liver remnant.
• For patients with a healthy liver - at least 20% of the total liver volume.
• Patients with abnormal background liver (i.e., following preoperative chemotherapy) - at least
30% the total liver volume
• Cirrhotic liver - at least 40%
• Volumetry of the FLR can be performed.
• The volume of the expected remnant liver and the total liver volume are measured using either CT scan or
MRI.
• Alternatively, the total liver volume can be estimated with different formulas based on the patient’s weight or
body surface area.
• Portal vein embolization (PVE) should be considered for patients with insufficient FLR. PVE
involves selective occlusion of the branches of the portal vein feeding the segments planned for
resection, inducing contralateral hypertrophy.

Associating Liver Partition and Portal Vein Ligation in
Staged Hepatectomy (ALPPS)
• One of the main surgical innovations in recent years.
• The procedure, invented by chance, by Dr. Hans Schlitt from Germany
• He observed in an intended extended right hepatectomy for hilar cholangiocarcinoma. In the surgery, palliative left
hepaticojejunostomy was performed because the FLR was small, with division of the liver parenchyma along the
falciform ligament and ligation of the right portal vein.
• On day 8 after the surgery, CT was done and it showed that the left lateral section had grown enormously in size.
• The diseased portion of the liver was subsequently removed in another surgery.
• The idea of ALPPS is to speed up hypertrophy of the FLR (the left lobe or the left lateral section) by right portal vein
ligation and in-situ splitting of the intended transection surface down to the inferior vena cava

ANESTHETIC CONSIDERATIONS
• Adequate hemodynamic monitoring & Intraoperative venous access should be
appropriate to prepare for the possibility of major intraoperative bleeding.
• To minimize bleeding during parenchymal transection, the anesthesiologist must
maintain a low and controlled central venous pressure (CVP) below 5 mm Hg.
• Patient is not given much fluid until parenchymal transection is complete.
• To prevent air embolism, the dissection has traditionally been performed with the
patient in a 15 degree Trendelenburg position (uncommon).
• Low CVP is maintained by minimal fluid resuscitation and agents that promote
venodilation.
• Once the specimen is removed, hemostasis is ensured and the patient
resuscitated to a status of euvolemia.

Operative Considerations - Preoperative Preparation
• Appropriate antibiotic prophylaxis
• Correction of anemia and coagulopathy
• Patients with a significant history of active cardiopulmonary disease
should undergo any indicated investigations and optimization before
undergoing resection.
• All patients with chronic liver disease or cirrhosis are assessed
carefully for the possibility of present or past infection with hepatitis
B or C virus, for a history of alcohol abuse, and for the magnitude of
liver dysfunction, as assessed by the CTP criteria, Model for End-Stage
Liver Disease (MELD) score, and preoperative platelet count.

Operative Procedure
• The patient should be positioned supine with the right arm extended at a right angle to
the body.
• draping should expose the lower chest up to the nipple line and the entire upper
abdomen to below the umbilicus
• INCISIONS:
• Bilateral subcostal incision. The midline incision should include excision of the xiphoid process.
• A J-shaped incision (popularized by M. Makuuchi) facilitates exposure of segments VII, VIII, or the
bulky tumor involving the right diaphragm.
• When the abdomen is opened, the entire peritoneal cavity should be explored. In
particular, the structures occupying the free edge of the lesser omentum, lymph nodes
related to the hepatic artery and the celiac axis, and supraduodenal nodes should be
assessed.

• The ligamentum teres is secured,
and division of the falciform
ligament is begun.
• The falciform ligament is divided
backward to expose the
suprahepatic IVC.
• Suprahepatic exposure of the
major hepatic veins and IVC after
division of the upper falciform
ligament.

Inflow control
• Pringle Maneuver –
• Occlusion of the portal triad can be performed prior to the transection of the parenchyma to
decrease blood loss.
• The liver can tolerate up to 1 hour of ischemia but intermittent vascular occlusion with cycles
of 15 to 20 minutes on and 5 minutes off will decrease the ischemia/reperfusion injury.
• Total ischemic time should not exceed 120 minutes.
• An alternative technique for inflow control includes ligation of the right portal
pedicle intrahepatically, either prior to or after transection of the parenchyma.
• In the Glissonian technique, the pedicle to the right liver is controlled prior to the
transection of the parenchyma with two incisions: one incision is made at the left
base of the gallbladder fossa just above the hilum and another is made at the
junction of segment VII and the caudate process. This second incision is
perpendicular to the hilum. A large curved clamp is passed above and behind the
right hilar pedicle to emerge in front of the IVC. An umbilical tape encircling the
pedicle is drawn to the left and the pedicle is transected with a vascular stapler.

Outflow control
• The major danger in controlling hepatic venous outflow is the risk of
hemorrhage.
• Intrahepatic control of the hepatic veins during parenchymal transection is
feasible and acceptable for tumors that allow clearance superiorly with
adequate tumor margins and with safe intrahepatic access to these vessels.
• Extrahepatic dissection and control of the major hepatic veins is possible in
almost all cases.
• Extrahepatic venous control necessitates two essential requisites that are
applicable for all hepatic resections: (1) maintainence of low CVP below 5
mm Hg and (2) precise extrahepatic dissection of the major hepatic veins.
• Dissection should be performed with the patient in a 15 degree
Trendelenburg position to minimize the risk of air embolism.

Parenchymal Transection
• Simple crushing technique. The Glisson capsule is scored with diathermy along
the line of proposed transection, and a Kelly clamp is used to crush the liver
tissue and expose small vessels, biliary channels, and larger pedicles; once
exposed, these structures can be secured and divided by using a variety of
techniques.The most simple and economic method is to use clips and suture
ligation.
• However, a variety of devices can be used, including computer- controlled bipolar
cautery (LigaSure; Valleylab, Boulder, CO), a saline-linked radiofrequency ablation
monopolar device (TissueLink;TissueLink Medical, Dover, NH) or bipolar variation
(Aquamantys,TissueLink Medical), or a Harmonic Scalpel (SonoSurg; Olympus Key
Med, New York).
• Surgicel or fibrin sealants also may be applied to the cut surface of the liver to
achieve final hemostasis after transection is complete.

Surgical Devices for Liver Parenchyma Division
• Clamp Crushing
• Ultrasonic Dissector - Cavitron Ultrasonic Surgical Aspirator (CUSA), is a device used to crush the
liver parenchyma, remove crushed tissues, and expose fibrous tissues (Glisson’s triads, hepatic
vein), with an ultrasonic vibration at its tip. The vessels must be exposed so that they can be
occluded with ligation or sealing.

• Vessel-Sealing System - Using bipolar electrothermal energy, a vessel-sealing
system can seal the vessel wall by denaturing the collagen and elastin in the wall
and completely occluding the blood vessel. During liver parenchyma division, the
vessel-sealing system can easily occlude vessels exposed by clamp crushing or an
ultrasonic dissector. Thus the use of the vessel-sealing system can shorten the
liver transection time and thus reduce the amount of blood loss.
• Ultrasonic Scalpel and Multiprobe Bipolar Radiofrequency Device - The active
blade of an ultrasonic scalpel vibrates 55,500 times per second, producing
frictional heat in contact with the tissues. The protein in the tissues is denatured
into an adhesive material called coagulum to seal the vessel. An ultrasonic scalpel
enables vessels to be cut immediately after sealing.
• Automatic Suture Device (Vascular Stapler) For laparoscopic liver resection, an
automatic suture device is now an indispensable tool frequently used to cut the
Glisson’s triads and hepatic vein.

Complications
• Liver Failure after liver resection is the most critical complication that
results in mortality, and several criteria have been proposed to predict it in
an early stage.
• If hyperbilirubinemia or refractory ascites (suggesting liver failure)
develops, intensive care should be started, including plasma exchange.
• However, no effective treatments other than liver transplantation have
been established for postoperative liver failure.
• Thus prevention is extremely important. The liver volume remnant should
be kept suitable for a patient’s liver functional reserve. In addition, any
other potential causes of liver failure should be avoided, such as excessive
blood loss followed by excessive RBC transfusion, bile leakage, sepsis, and
hypovolemia.

• Bile Leakage remains a major complication (6%-11%). In most cases,
postoperative bile leakage will subside with conservative treatments;
however, major bile leakage can cause critical liver failure.
• Postoperative Bleeding was reported as approximately 1%, with bleeding
occurring within 48 hours after surgery in most cases. Conservative
therapies, including transfusion, are the first choice; however, spontaneous
hemostasis can be difficult to achieve in because of the associated bleeding
tendency through thrombocytopenia and decrease in coagulation factors.
In such cases, emergent reoperation for hemostasis should be considered.

• Refractory Ascites most common postoperative complications (5% to 56%) and can lead
to liver failure when large amounts of plasma are continuously lost in ascitic fluid. To
prevent refractory ascites, the perioperative use of diuretic agents is recommended.
Spironolactone, is regarded as the first choic.
• Surgical site infection is a common complication after abdominal surgery. Its incidence
after liver resection, which is classified as a semiclean surgery is about 5% to 15%.
However, sepsis as a result of infection can cause liver failure, even in cirrhotic cases
associated with potential immune insufficiency. The use of antibiotics is an essential
component of perioperative management to prevent infection.
• Peptic Ulcer - To prevent postoperative peptic ulcers, the routine administration of
proton pump inhibitors or histamine-2 receptor blockers is recommended, since liver
cirrhosis itself is associated with a high risk of peptic ulcers, and this risk could be
increased by perioperative mental and physical stress. If a peptic ulcer is observed before
surgery, the liver resection should be post- poned until a healing stage of the peptic ulcer
can be confirmed by endoscopy.

Symptoms of Post hepatectomy liver failure
Major hepatectomy is associated with reduced synthetic, detoxification, and immune responses with
potentially life-threatening complications, such as hepatic encephalopathy, increased susceptibility to
infections and sepsis, renal failure, coagulopathy, and hemodynamic instability.
The indications for major hepatectomies have expanded during the last 20 years, and also high-risk patients
with steatosis, fibrosis, and chemotherapy-induced liver injury are included.
Treatment options of PHLF include intensive medical care focused on treating the complications until the
remnant liver recovers. These patients often require prolonged stays in intensive care units. Liver support
devices may be considered and, as a last resort, (rescue) liver transplantation.
• There are several proposed definitions of PHLF or postoperative hepatic insufficiency. One of the more
practical definitions was introduced by Balzan and colleagues (2005), applying the “50-50” criteria:
prothrombin index of less than 50% (equal to an INR >1.7 and serum bilirubin >50 μmol/L (>2.9 mg/dL) on
postoperative day 5 after hepatic resection.
• Non biological/ biological support system in PHLF - preliminary results are promising. Randomized controlled
studies are warranted in evaluating liver support devices in PHLF. Future studies should address when to
initiate liver support therapy and the duration of therapy.

Hepatectomy

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