-
159
Hepatic resection is appropriate treatment for a vari-ety of
benign and primary or secondary malignanthepatic lesions. In
appropriate patients with malig-nant disease, resection generally
offers the bestopportunity for long-term survival or cure.
Inpatients with benign tumors, resection is safe andeffective when
carried out for symptoms directlyrelated to the tumor.
In patients with malignant tumors submitted to apotentially
curative operation, complete resectionrequires a negative
histologic margin. Previously, amargin of 1 cm of normal parenchyma
was consid-ered essential, but recent studies have suggested
thatthis is not necessarily the case, and margins of lessthan 1 cm
are adequate.1,2 In many cases, tumorproximity to major vascular
structures will precludea resection margin of more than a few
millimeters,which is generally sufficient. Regardless,
anatomi-cally based partial hepatectomy is the best means
ofachieving a negative margin. Wedge resections areusually
inadequate and potentially dangerous, espe-cially for large tumors,
and are often associated withgreater blood loss and a greater
incidence of positivehistologic margins.3 Anatomic segmental
resectionsare much more controlled and are generally superiorto
wedge resections.
Hepatic resection for benign hepatic tumors maybe indicated for
relief of symptoms (such as pain orearly satiety), for uncertainty
in diagnosis, or forlesions with malignant potential. In contrast
to thesituation with malignant tumors, however, mostbenign tumors
can be removed with maximal spar-
8Techniques of Hepatic ResectionHOWARD M. KARPOFF, MDWILLIAM R.
JARNAGIN, MDJOS MELENDEZ, MDYUMAN FONG, MD, FACSLESLIE H. BLUMGART,
MD, FACS, FRCS (ENG, EDIN, GLAS)
ing of normal parenchyma. Consequently, lesionssuch as
hemangiomas, adenomas, complex cysts, orfibronodular hyperplasia
are often excised by enu-cleation (Fig. 81) or anatomic resections
with lim-ited margins.
The fear of uncontrolled hemorrhage was a majorimpediment to the
evolution of hepatic resection as aneffective form of therapy.
While bleeding remains aconcern, operative technique has improved
greatly,and experienced centers have realized significantreductions
in blood loss and transfusion requirements,even after major
resections. Portal-triad clampingreduces hepatic arterial and
portal venous bleedingbut does not address the hepatic veins, which
are usu-ally the major source of blood loss. Our approach tohepatic
resection, developed by the senior author,involves inflow and
outflow vascular control beforeparenchymal transection, low central
venous pressureanesthesia to minimize hepatic venous bleeding,
andanatomically based resections. Using this approach,we have
reduced the median blood loss to less than1 L and the number of
patients requiring transfusionto less than half.4 Some authors use
the technique oftotal vascular isolation routinely for all
resections.This is a fundamentally different approach that maybe
useful in a handful of cases. Moreover, Belghitiand colleagues, in
a prospective study, found that totalvascular isolation offered
little advantage to theapproach described above and was actually
associatedwith greater blood loss.5 In our experience of
approx-imately 1,700 hepatic resections since 1992, we havenot
found it necessary to use vascular isolation.
-
Figure 82. Segmental anatomy of the liver according to
Couin-aud. A, The major hepatic veins divide the liver into
sectors. The mid-dle hepatic vein divides the liver into right and
left sides. The umbili-cal fissure (and left hepatic vein) divides
the right lobe from the leftlobe. (Reprinted with permission from
Bismuth H, Clich L. Surgicalanatomy and anatomical surgery of the
liver. In: Blumgart LH, editor.Surgery of the liver and biliary
tract. 2nd ed. Edinburgh [UK]:Churchill Livingstone; 1994. p. 5.)
B, Ex-vivo view. Note the positionof the caudate lobe. (Reprinted
with permission from Bismuth H,Clich L. Surgical anatomy and
anatomical surgery of the liver. In:Blumgart LH, editor. Surgery of
the liver and biliary tract. 2nd ed.Edinburgh [UK]: Churchill
Livingstone; 1994. p. 5.) C, A corrosioncast demonstrating the
segmental nature of the liver structure.
C
A B
160 HEPATOBILIARY CANCER
Figure 81. Enucleation of a giant hemangioma from the right
liver. The hemangioma is beingprogressively elevated as vessels are
dissected and controlled. The middle hepatic vein is seenlying
exposed in the floor of the cavity (arrow).
-
Techniques of Hepatic Resection 161
In this chapter, we describe the techniques ofliver resection,
including anatomic, anesthetic, andtechnical considerations, as
well as preoperative andpostoperative care.
ANATOMY
A thorough understanding of the anatomy of theliver is necessary
for any surgeon contemplatinghepatic resection. The nomenclature is
from thedescriptions of Couinaud,6,7 which divides the liverinto
eight segments based on the branches of theportal triad and hepatic
veins (Fig. 82).
Surface Anatomy, Relationships,and Peritoneal Attachments
The surface of the liver is related to the diaphragmand to the
viscera (Fig. 83). The hepatic flexure andtransverse colon extend
from the right side of theliver to the medial aspect of the left
lobe. Posteriorto the colon are the adrenal gland and right
kidney.
The falciform, round, and coronary ligamentsattach the liver to
the anterior abdominal wall and tothe diaphragm. The triangular
ligaments attach theright and left edges of the liver. The coronary
liga-ment, a reflection of the peritoneum of the liver
reflected onto the diaphragm, has an anterior and pos-terior
leaf. Between these two leaves lies the bare areawhere the liver is
in contact with the diaphragmdirectly. The anterior leaf extending
over the superioraspect of the liver becomes the falciform ligament
asit folds over and attaches to the anterior abdominalwall. Within
the fold of the falciform lies the liga-mentum teres (round
ligament), the left umbilicalvein remnant, which enters the liver
in the umbilicalfissure. The ligamentum venousum (the
obliteratedumbilical vein) runs within the ligamentum teres,courses
along the anterior surface of the caudate lobe,and attaches to the
left hepatic vein. The umbilical fis-sure divides the liver into
right and left lobes (Fig.84). The transverse hilar fissure lies at
the visceral
Figure 83. Surface anatomy of the liver, showing the
peritonealattachments. Within the broken lines lies the bare area
of the liver.TL = triangular ligament; CL = coronary ligament; FL =
falciform lig-ament. (Reprinted with permission from Trunkey DD.
Treatment ofmajor hepatic trauma. In: Nyhus LM, Baker RJ, Baker JE,
editors.Mastery of surgery. 3rd ed. Little, Brown; p. 1074.)
Figure 84. Surface morphology of the liver. Anterior view:
Theumbilical fissure divides the liver into right and left lobes.
Inferior view:The quadrate lobe (segment IV) lies anterior to the
transverse hilarfissure and is bounded by the gallbladder fossa on
the right and theumbilical fissure on the left. The caudate lobe
lies posterior to the fis-sure and anterior to the inferior vena
cava. (Reprinted with permissionfrom Bismuth H, Chich L. Surgical
anatomy and anatomic surgery ofthe liver. In: Blumgart LH, editor.
Surgery of the liver and biliary tract.2nd ed. Edinburgh [UK]:
Churchill Livingstone; 1994. p. 3.)
-
162 HEPATOBILIARY CANCER
Figure 85. Vascular inflow of the caudate lobe (I). The
caudatereceives its main inflow from branches of the left portal
vein. IVC =inferior vena cava; MHV = middle hepatic vein; LHV =
left hepaticvein; PV = portal vein; RPV = right portal vein; LPV =
left portal vein.Reprinted with permission from Blumgart LH. Liver
resection forbenign disease and for liver and biliary tumors. In:
Blumgart LH,Fong Y, editors. Surgery of the liver and biliary
tract, 3rd ed. Edin-burgh [UK]. Churchill Livingstone; 2000.
surface of the right lobe. The quadrate lobe (segmentIV) lies
anterior to the fissure and is limited by thegallbladder fossa on
the right and the umbilical fis-sure on the left. Posterior to the
transverse fissure andanterior to the inferior vena cava is the
caudate lobe.
A layer of peritoneum from the liver to the stom-ach forms the
lesser omentum, extending to thelesser curvature of the stomach as
the hepatogastricligament and as the hepatoduodenal ligament at
theproximal duodenum. The hepatic artery, portal vein,and common
bile duct are contained within thehepatoduodenal ligament.
Sectors and Segments
Within the substance of the liver is a complex seg-mental
organization that belies the simple lobar divi-sions evident on the
surface. The structures of theportal triad (hepatic artery, portal
vein, and biliaryduct) are separate extrahepatically but enter
thehepatic hilus afterward, ensheathed within a thick-ened layer of
Glissons capsule. The three mainhepatic veins divide the liver into
four sectors, eachof which is supplied by a portal pedicle. The
caudatelobe is an exception since its venous drainage isdirectly
into the vena cava and therefore independentof the major hepatic
veins. The four sectors delimitedby the hepatic veins are called
the portal sectors, andthese portions of the parenchyma are
supplied byindependent portal pedicles that arise from the rightor
left main pedicles. The divisions separating thesectors are called
portal scissurae, within each ofwhich runs a hepatic vein. Further
branching of thepedicles subdivide the sectors into segments.
Theliver is thus subdivided into segments, numbered Ithrough VIII,
with the caudate lobe designated assegment I. At operation, each
segmental pedicle canbe identified and occluded or clamped to
delineateits precise parenchymal distribution.
The right and left liver are separated anatomi-cally by an
imaginary line running from the medialaspect of the gallbladder
fossa anteriorly to the infe-rior vena cava (IVC), running parallel
with the fis-sure of the round ligament. This is known asCantlies
line or the principal plane and contains themiddle hepatic vein.
The left liver consists of themedial and lateral sectors or
segments. Segments II
and III make up the left lobe (also referred to as theleft
lateral segment). Segments III and IV (thequadrate lobe), separated
by the umbilical fissure,together constitute the medial sector of
the left liver,being themselves delineated from the right liver
bythe main scissura containing the middle hepaticvein. Segments I
to IV thus make up the left liver.Similarly, the right liver is
further divided into ante-rior and posterior sectors by the plane
of the righthepatic vein. Thus, the right liver consists of
seg-ments V and VIII (anterior sector) and segments VIand VII
(posterior sector).
The caudate lobe is considered separately sinceits blood supply
and biliary drainage arise from boththe right and left sides;
however, the main pedicle tothe caudate lobe originates from the
left (Fig. 85).The caudate lobe lies between the left portal
veinand the IVC and extends to the hepatic venous con-fluence. Some
authors consider the caudate lobe toconsist of three parts: (1) the
Spigel lobe, whichextends to the left of the IVC (Fig. 86); (2)
theparacaval portion anterior to the IVC; and (3) thecaudate
process, which attaches the caudate lobe tothe right liver. The
medial border of the caudatelobe, within the substance of the
liver, is poorly
-
Techniques of Hepatic Resection 163
defined (Fig. 87). A ligamentous band from theSpigel lobe often
passes posterior to the IVC andattaches to segment VII (Fig. 88);
in some patients,this band consists of hepatic parenchyma.
Venousdrainage from the caudate lobe occurs through mul-tiple
branches directly into the IVC and is indepen-dent of the major
hepatic veins (Fig. 89).
Pedicles
Outside the liver, in the hilum, the major branches ofthe portal
vein and hepatic artery and tributaries ofthe bile ducts can be
individually dissected afterdividing the peritoneum. They divide
into majorright and left branches. The right portal vein often
Figure 86. The caudate lobe as seen bycomputed tomography. A,
The caudate lobe liesbetween the left portal vein (LPV) and the
infe-rior vena cava (IVC). The Spigel lobe (S) extendsto the left
of the IVC. B, The caudate process(thick arrow) lies between the
right portal vein(RPV) (thin arrow) and the IVC and is part
ofsegment VI.
A
B
-
Figure 87. Anatomic relationships of the caudatelobe (segment
I). The medial border of the caudatelobe lies within the substance
of the liver and ispoorly defined (dashed lines). MHV = middle
hepaticvein; LPV = left portal vein; IVC = inferior vena
cava.Reprinted with permission from Blumgart LH. Liverresection for
benign disease and for liver and biliarytumors. In: Blumgart LH,
Fong Y, editors. Surgery ofthe liver and biliary tract. 3rd ed.
Edinburgh [UK].Churchill Livingstone; 2000.
Figure 88. The anatomy of the caudate lobe. A ligamentous
bandfrom the Spigel lobe passes posterior to the inferior vena
cava,attaching to segment VII (arrowhead).The principal inflow
blood sup-ply arises from the left (small arrow). IVC = inferior
vena cava; LHV= left hepatic vein; LV = left ventricle; RL = right
lobe. (Reprinted withpermission from Yanaga K, Matsumata T, Hayashi
H, et al. Isolatedhepatic caudate lobectomy. Surgery
1994;115:759.)
164 HEPATOBILIARY CANCER
has a short extrahepatic course, and care must betaken not to
damage a branch arising posteriorlynear the bifurcation, extending
to the caudateprocess. The biliary anatomy on the right side maybe
aberrant, making that side vulnerable and easilydamaged during
dissection. In contrast, the left por-tal vein and left hepatic
duct generally are more con-stant and have a longer and more
horizontal extra-hepatic course below the quadrate lobe (Fig.
810).The portal triads then enter into the liverparenchyma, where
they are surrounded by well-formed fibrous sheaths (extensions of
Glissons cap-sule) and where they form the portal pedicles.8
The left portal pedicle enters the liver within theumbilical
fissure and provides branches to segmentsII and III, as well as
feedback branches to segmentIV (the medial segment or quadrate
lobe).9
Hepatic Artery
Typically, the common hepatic artery arises from theceliac axis,
giving rise to the gastroduodenal andproper hepatic arteries. The
proper hepatic arterydivides into right and left branches before
enteringthe liver; the point at which the proper hepatic
arterygives rise to left and right hepatic arteries is
quitevariable. The right hepatic artery passes beneath thecommon
bile duct in most cases. A variety ofanatomic anomalies are
possible, however, although
only a few are seen frequently. A replaced or acces-sory right
hepatic artery arises from the superiormesenteric artery and
courses posterolateral to thebile duct within the porta hepatis.
This variation isseen in 25 percent of patients. An accessory
orreplaced left hepatic artery, arising from the left gas-
-
Techniques of Hepatic Resection 165
tric artery and entering the liver within the gastro-hepatic
omentum, is seen in about 20 percent of thepopulation. Other
variations that may be encoun-tered include a completely replaced
hepatic artery
arising from the superior mesenteric artery and theanomalous
origin of a left medial (segment IV)branch such that the left
hepatic artery supplies onlysegments II and III.
Figure 810. The anatomy of the left portal system. The left
ductal system has a horizontal coursebelow the quadrate lobe. A,
The hilar plate (arrow) is formed by the fusion of connective
tissue enclosingthe biliary and vascular elements and Glissons
capsule. B, The hilar plate is lowered, and the quadratelobe is
retracted upward to expose the left hepatic duct and left portal
vein. This technique is useful forexposing the bile duct above an
iatrogenic injury of a proximal bile duct cancer. (Reprinted with
permis-sion from Smadja C, Blumgart LH. The biliary tract and the
anatomy of biliary exposure. In: Blumgart LH,editor. Surgery of the
liver and biliary tract. 2nd ed. Edinburgh [UK]: Churchill
Livingstone; 1994. p. 14)
Figure 89. The caudate lobe. Venous drainage from the caudate
lobe occurs through multiple directbranches (one of which is being
exposed) into the inferior vena cava.
A B
-
166 HEPATOBILIARY CANCER
Hepatic Veins
The hepatic veins course between the sectors, pro-viding venous
drainage for the adjacent segments.The main hepatic venous trunks
have a short extra-hepatic course before joining the IVC. The
righthepatic vein runs within the right scissura and entersthe cava
separately. The right vein drains both theanterior and posterior
sectors. The left hepatic veinruns in the left scissura (between
segments II andIII) and commonly joins the middle hepatic vein(from
the principal scissura) prior to entering thecava. The left vein
may also enter the cava indepen-dently. The left hepatic vein
drains the lateral seg-ment as well as the medial superior segment.
Anumbilical vein (within the umbilical fissure and ofvariable size)
often enters the left hepatic vein nearits confluence with the
middle hepatic vein. This veincan maintain drainage of segment IV
if the middlehepatic vein is sacrificed at operation. The
middlehepatic vein drains the anteroinferior segment andthe medial
inferior segment. A variable number ofsmall, unnamed veins, some of
which may be quitesubstantial in size, drain from the posterior
surface ofthe liver directly into the vena cava; from 2 to asmany
as 10 venous branches enter the IVC directlyfrom the caudate lobe.
Occasionally, a large inferiorright hepatic vein (see below) is
present, which mayassume importance during resection.
Portal Vein
The portal vein is formed from the merger of thesplenic vein
with the superior mesenteric vein pos-terior to the pancreas. The
inferior mesenteric usu-ally enters the splenic vein or the
confluence of thesplenic and superior mesenteric veins.
Severalsmaller veins, including the left gastric (coronary)vein and
often one or two jejunal branches, join theportal vein prior to its
entry into the liver. The portalvein usually divides into right and
left branches out-side the liver. Typically, the right vein has a
shortextrahepatic course before dividing into anterior andposterior
sectoral branches. The smaller left portalvein divides into medial
and lateral branches, sup-plying segment IV and segments II and
III, respec-tively. The main portal venous trunks usually havefew
branches outside the liver. However, a small
branch from the right vein to the caudate processand a branch
from the portal venous confluence tosegment IV are frequently
encountered and are ofimportance during resection (Fig. 811).
Aberrant portal venous anatomy is occasionallyseen, most
commonly involving the right vein. Theright anterior and posterior
sectoral branches mayarise independently, or the right anterior
trunk mayeven arise from the left portal vein. Congenitalabsence of
the left portal vein has been described inwhich a single portal
venous trunk enters the liver atthe hilum and provides branches to
the right and leftsides from within the parenchyma. Although
uncom-mon, these variations assume great importance dur-ing
resection and must be recognized to avoid inter-ruption of the
portal flow to the liver remnant.
Lymphatic Drainage of the LiverIn the connective tissue beneath
Glissons capsule liethe superficial lymphatics. Drainage is
superior tothe anterior and middle phrenic nodes and inferior tothe
hepatic nodes. The deep lymphatics drain up tothe middle phrenic
and down to the nodes of theporta. These portal nodes may also
drain to nodesalong the hepatic artery to the celiac nodal
basin.
The anatomy of the liver is the foundation ofmodern hepatic
resectional surgery and provides thesurgeon with flexibility
regarding the types of resec-tion that are possible (Fig. 812).
Major resections(lobectomy or trisegmentectomy) remain the
mostcommonly performed procedures. However, morelimited resections
(such as isolated segmentec-tomies or bisegmentectomies) are being
performedwith increasing frequency in the appropriate setting.These
more limited resections are oncologicallysound, spare uninvolved
hepatic parenchyma, andmay result in lower postoperative morbidity
andshorter hospital stay. Our general approach to
partialhepatectomy (described in detail in the followingsections)
relies on initial inflow and outflow vascu-lar control, with
subsequent parenchymal transec-tion along anatomic planes.
PREOPERATIVE EVALUATION
The preoperative evaluation begins with a thoroughhistory and
physical examination that assesses not
-
Techniques of Hepatic Resection 167
only the present illness but also the patients generalhealth. It
is especially important to identify underly-ing comorbid medical
conditions or chronic underly-ing liver disease that would preclude
a major hepaticresection. Although chronic liver disease is not
anabsolute contraindication to liver resection, the mor-bidity and
mortality increases prohibitively withincreasing hepatic
dysfunction. Childs class B or Cpatients are generally excluded
from major resec-tions whereas Childs A patients may be
candidates.10
Radiologic studies should also be scrutinized for evi-dence of
portal hypertension, such as splenomegaly,collateral venous
circulation, or ascites.
For patients with cancer, determining the extentof disease is
obviously a critical component of theevaluation. The pathology, if
any, should be reviewedand appropriate imaging studies obtained to
assessthe hepatic disease and the feasibility of resection.Any
suspicion of extrahepatic disease should be pur-sued with a biopsy
since such disease almost alwaysprecludes any possibility of a
curative resection.
In patients with malignant disease but who areotherwise
considered candidates for resection,assessment of resectability
should be made by anexperienced surgeon. Tumors are potentially
resectable if they can be removed completely (nega-tive
histologic margin) while leaving behind an ade-quate well-perfused
liver remnant with an intact bil-iary and hepatic venous drainage.
In a healthy,noncirrhotic patient, up to 80 percent of the
func-tional parenchyma can be removed with a reasonableexpectation
of subsequent regeneration. The techni-cal feasibility of tumor
removal is predicated on theindividual surgeons judgment and skill.
In selectingpatients for resection, preoperative imaging
studiesclearly play a critical role in patient selection.
Ultrasonography (US) is a noninvasive modalitythat can provide
useful information regarding size,extent, and characteristics of
hepatic lesions.Although operator-dependent, it may be
particularlyuseful in characterizing small lesions,
distinguishingsolid from cystic lesions, and assessing major
vascu-lar structures for patency or tumor involvement.11 Wefind
duplex US particularly useful for assessingpatients with hilar
cholangiocarcinoma.
Helical computed tomography (CT) withdynamic studies makes
excellent detailed images ofthe liver, providing critical anatomic
informationregarding tumor proximity to major pedicles andhepatic
veins. It may also help in characterizing the
Figure 811. Branches of the portal system outside the liver;
dissection of the portal veinwithin the porta hepatis.The right
branch of the portal vein is isolated in a vessel loop. A
smallbranch of the portal vein (small arrow) draining the caudate
process (large arrow) has beentied and is being divided. This
branch is a constant finding and must be controlled to
avoidhemorrhage during dissection in this area.The divided right
hepatic artery is being retractedto the left (arrowhead).
-
168 HEPATOBILIARY CANCER
type of lesion. Hemangiomas and other benignlesions have
characteristic appearances on CT,which may help establish the
diagnosis if in doubt.Computed tomography will also reveal lobar
atro-phy, a little-appreciated yet important finding that ishighly
suggestive of portal venous involvement bytumor. Computed
tomography is also useful inassessing the abdomen and pelvis for
extrahepaticdisease and involvement of adjacent organs. CurrentCT
techniques also allow three-dimensional recon-struction of vascular
structures, which may be help-ful for planning the resection or for
assessing thehepatic arterial anatomy in patients being
consideredfor hepatic artery pump placement (Fig. 813).
Magnetic resonance imaging (MRI) is provingincreasingly valuable
for differentiating benign frommalignant tumors and may also help
differentiateamong the various benign tumors. Like CT, MRIprovides
information regarding the number ofhepatic tumors and the
relationship of tumor to majorvascular structures. Moreover,
magnetic resonanceangiography (MRA) and
cholangiopancreatography(MRCP) are emerging modalities that
providedetailed images of the hepatic vascular and biliary
tract anatomy, respectively. In our experience, MRCPcombined
with duplex US is the investigation ofchoice for evaluating
patients with proximal biliaryobstruction and will likely supplant
direct cholan-giography for the routine evaluation of these
patients.
Angiography, previously a common preoperativeinvestigation, is
no longer used routinely. Advancesin cross-sectional imaging and
the detailed informa-tion provided by these studies have rendered
angiog-raphy unnecessary in most cases. Angiography isused most
often to assess arterial anatomy prior tothe placement of hepatic
arterial infusion pumps.However, even this role may well be
diminished asCT and MRA improve.
Laparoscopy has become a useful tool forassessing patients for
radiographically occult unre-sectable disease and thus avoiding
unnecessarylaparotomies. Some earlier reports have suggestedthat up
to 50 percent of patients considered to havepotentially resectable
tumors on radiologic groundshad unresectable disease, the majority
of whichwere identified at laparoscopy. More recently, in
aprospective comparison of staging laparoscopy tono laparoscopy, we
found that approximately two-
Figure 812. Hepatic resections and nomenclature. A, The various
resections and their namesare indicated on the left as segmental
resections. B, The major hepatic resections: (A) right
hepa-tectomy, (B) left hepatectomy, (C) right lobectomy, (D) left
lobectomy, (E) extended left lobectomy.(Reprinted with permission
from Blumgart LH. Liver resectionliver and biliary tumours. In:
Blum-gart LH, editor. Surgery of the liver and biliary tract. 2nd
ed. Edinburgh [UK]: Churchill Livingstone;1994. p. 1495.)
-
Techniques of Hepatic Resection 169
thirds of patients underwent a potentially curativeresection and
that only 17 percent avoided anunnecessary laparotomy. Despite this
low yield,however, laparoscopic identification of unre-sectable
disease significantly reduces length of stayand hospital
costs.12
OPERATIVE TECHNIQUE
Preparation
Preparing a patient for major hepatic resectionrequires the
correction of underlying metabolicabnormalities, anemia, or
coagulapothy. Jaundicedpatients should be appropriately hydrated
preopera-tively. Patients over the age of 65 years or at
signifi-cant risk of cardiopulmonary disease should be eval-uated
by a cardiologist for fitness for surgery. Asingle preoperative
dose of antibiotics is used forroutine cases; however, in patients
with indwellingbiliary stents undergoing concomitant biliary
resec-tion, it is our practice to continue
broad-spectrumantibiotics in the postoperative period.
Anesthesia
A major hepatic resection requires communicationbetween the
surgeon and the anesthesiologist. Majorlife-threatening hemorrhage
can occur quickly. Arte-rial lines and large-bore peripheral access
and cen-tral venous access lines are placed once the decisionis
made to proceed with resection. Very large softtumors such as
hepatocellular carcinomas ormetastatic sarcomas may be
inadvertently disruptedduring initial mobilization, resulting in
significanthemorrhage, and the surgeon should be prepared forthis
possibility. Also, esophageal temperature probesare used to monitor
the patient for hypothermia.
Most intraoperative blood loss results frominjury to the hepatic
veins and the vena cava. Severalsteps are taken to minimize the
venous bleeding.Dissection and control of the hepatic veins is
usuallyperformed prior to parenchymal transection, and thevenous
outflow draining the liver to be removed isdivided after dividing
the inflow vessels. Mobiliza-tion and parenchymal transection are
performedwith a low central venous pressure (CVP) generallyno
higher than 5 mm Hg, which minimizes bleeding
Figure 813. Three-dimensional computed tomographic arteriography
showing the arterial anatomyof the liver, with the common hepatic
artery giving rise to the gastroduodenal artery (arrow) and the
lefthepatic and right hepatic branches. A small branch to segment
IV, arising from the right hepatic artery,is also seen (arrowhead).
(Courtesy of Corrine Winston, MD, Radiology Department, Memorial
Sloan-Kettering Cancer Center, New York.)
-
170 HEPATOBILIARY CANCER
from disrupted hepatic venous branches. The anes-thesiology team
uses early fluid restriction and anes-thetic techniques to maintain
this low venous pres-sure until transection is complete. Urine
output ismonitored to try to achieve the minimal volumeinfusion
necessary to maintain renal perfusion, butlow urine output during
the resection is accepted. Tominimize risk of air embolism from
disruptedhepatic veins, the resection is performed with thepatient
in the Trendelenburg position (15). We haveused this technique in
well over 1,000 patients andhave observed no clinically significant
instances ofair embolism. Likewise, in patients with no otherrisk
factors such as sepsis or underlying renal insuf-ficiency, the
impact of low CVP anesthesia on post-operative renal function is
minimal.2 On the otherhand, the advantages of this approach are
significantreductions in blood loss and perioperative transfu-sion
requirements. At present, less than one-third ofour patients
require any blood products in the imme-diate perioperative period,
and only one-half are
transfused at some point during their hospital stay.We encourage
all patients to donate one or two unitsof autologous blood before
operation, which furtherreduces the burden on the hospitals blood
bank.
Exploration
The patient is positioned supine, with the armsextended 90. We
place a crossbar retractor towardthe head of the table to allow
self-retaining retractorsto elevate the costal margin. Preparation
of the oper-ative field includes the area from the lower abdomenup
to and including the chest, extending from axil-lary line to
axillary line, thus allowing access to thethoracic cavity if a
thoracoabdominal incision orextension is required; this is uncommon
but shouldbe considered for large tumors that encroach uponthe
hepatic venous confluence. The majority of liverresections are
performed with either a right sub-costal incision with midline
extension or a chevronincision (Fig. 814).
Figure 814. Common incisions used for hepatectomy. Themajority
of liver resections may be done with a right subcostalincision with
midline extension (A, B, D) or a bilateral subcostalincision with
midline extension (A, B, C, D). F indicates a rightthoracic
extension; E indicates a median sternotomy.(Reprinted with
permission from Blumgart LH. Liver resectionliver and biliary
tumours. In: Blumgart LH, editor. Surgery of theliver and biliary
tract. 2nd ed. Edinburgh [UK]: Churchill Living-stone; 1994. p.
1504.)
-
Techniques of Hepatic Resection 171
Laparoscopy is generally performed immediatelyprior to
laparotomy. We place the laparoscopic portsin the upper abdomen
(Fig. 815), along the line ofthe intended incision. If unresectable
disease is notencountered (Fig. 816), a right subcostal incision
ismade initially, with subsequent extension of the inci-sion as
necessary. The round ligament is divided,leaving a long suture on
the hepatic attachment fortraction. The lymph nodes in the hilum
and retroperi-toneum are palpated, and suspicious nodes are sentfor
frozen-section analysis. The lower abdomen canbe examined manually
for recurrent disease. Thelesser omentum is divided, and the
caudate lobe isinspected and palpated. The falciform ligament
isdivided up toward the hepatic veins (Fig. 817). Theliver is then
freed of its diaphragmatic attachments.The right triangular
ligament and the coronary liga-ment are divided with cautery. Once
suitably mobi-lized, the liver is examined with bimanual
palpationand intraoperative ultrasonography (IOUS) (Fig.818) in a
systematic fashion to identify thetumor(s), assess for additional
disease, and assess therelationship of the tumor(s) to the major
vasculaturestructures (Fig. 819). The major pedicles andbranches to
all segments, the hepatic veins, and theparenchyma are evaluated in
turn. Intraoperative USis useful for confirming the preoperative
findings,but in our experience, the findings on IOUS alonechange
the operative plan in only about 10 percent ofpatients and rarely
identify unresectable disease.
If the decision is made to proceed, then mobi-lization of the
liver is completed. The right liver isfreed completely from the
diaphragm by dividingthe right triangular ligament and exposing the
barearea of the liver. This is facilitated by rotating thetable
away from the operating surgeon, having theassistant gently retract
the right lobe of the livermedially and anteriorly, and grasping
the diaphragmand pulling it laterally. In this position, the
attach-ments under tension may be divided on the surfaceof the
liver. The peritoneum at the inferior border ofthe liver is divided
lateral to medial to the IVC, tak-ing care not to injure the
adrenal gland. In somecases, tumors on the surface of the liver are
adherentto the diaphragm although diaphragmatic invasion israre. If
the lesion is otherwise resectable, the sur-geon should not
hesitate to resect a portion of the
diaphragm, which usually can be repaired primarilyafter the
resection. Small veins draining posteriorlyfrom the liver into the
IVC are carefully dissectedand divided from the caudate process up
to thehepatic venous confluence (Fig. 820). In the courseof this
dissection, a ligamentous band is encounteredthat extends from the
caudate lobe on the left, passesposterior to the IVC, and attaches
to segment VII.This ligament, which often contains small vessels
orhepatic parenchyma, must be divided in order to seeand control
the right hepatic vein.
The left liver is mobilized by dividing the left tri-angular
ligament and left coronary ligament to thelateral margin of the
IVC, taking care to avoid injur-ing the left hepatic vein. The
lesser omentum shouldbe divided completely. The ligamentum
venosumshould also be divided between clips or ties.
Right Hepatectomy
Right hepatectomy involves removing all hepaticparenchyma to the
right of the middle hepatic vein
Figure 815. Laparoscopic port site placement. The laparo-scopic
ports are placed in the line of the intended incision. Three10-mm
ports are placed to allow for laparoscopic ultrasonography.
-
172 HEPATOBILIARY CANCER
(segments V, VI, VII, and VIII). After full mobiliza-tion and
assessment, the surgeon should proceedwith vascular inflow and
outflow control. Three gen-
eral approaches have been described for achievingvascular inflow
control: (1) extrahepatic dissectionwithin the porta hepatis, with
division of the right
Figure 817. The ligamentum teres. A, The ligamentum teres is
secure, and the falciform ligament is divided. B, The falciform
ligament isdivided up toward the hepatic veins to expose the
inferior vena cava. (Reprinted with permission from Blumgart LH.
Liver resectionliver andbiliary tumours. In: Blumgart LH, editor.
Surgery of the liver and biliary tract. 2nd ed. Edinburgh [UK]:
Churchill Livingstone; 1994. p. 1505.)
Figure 816. Unresectable disease found at the time of
laparoscopy. This patient has peritoneal dis-ease not seen on
computed tomography scan but seen at the time of laparoscopy. The
resection wasaborted, and the patient was spared a laparotomy.
A B
-
Techniques of Hepatic Resection 173
hepatic artery and right portal vein prior to divisionof the
parenchyma (Fig. 821); (2) intrahepatic con-trol of the main right
pedicle within the substance ofthe liver prior to parenchymal
transection (pedicleligation)13; and (3) intrahepatic control of
the pedi-cle during parenchymal transection. For the over-whelming
majority of resections, we control theinflow extrahepatically with
hilar dissection or withthe pedicle ligation technique. In general,
it is not
advised to proceed with liver resection before inflowcontrol can
be achieved.
Pedicle ligation, an approach described byLaunois, has several
advantages over hilar dissec-tion. After removing the gallbladder,
hepatotomyincisions are made medially at the base of the
gall-bladder fossa and within the caudate process, paral-lel to the
IVC (Fig. 822). With the portal triadclamped (Pringle maneuver), a
finger or clamp is
Figure 818. Intraoperative ultrasonography.
Figure 819. The use of intraoperative ultrasonography. A,
Computed tomography scan showing a lesion in segmentIV. B,
Intraoperative ultrasonography image showing the anatomic
relationship of the lesion to the portal vein and show-ing the left
hepatic duct (arrow).
A B
-
174 HEPATOBILIARY CANCER
then passed into the substance of the liver to encir-cle the
main right pedicle. Some bleeding from ter-minal branches of the
middle hepatic vein may be
encountered, but this is readily controlled. A smallamount of
residual liver tissue is then cleared awayto expose the pedicle.
Further dissection along thepedicular sheath allows a means of
identifying theanterior or posterior pedicles or branches to
individ-ual segments for segmental or sectoral resections.Before
attempting this maneuver, it is imperative todivide all venous
branches entering the IVC fromthe right lobe; otherwise, these
veins may be torn,and significant hemorrhage will ensue. With
theright pedicle so isolated, it may be occluded and
theportal-triad clamp released to reveal a clear line ofdemarcation
along the principal plane and thendivided. The right portal pedicle
may be taken as asingle unit, or the anterior and posterior
pedicles canbe divided separately. Pedicle ligation eliminates
theneed for hilar dissection, thereby saving time andalso reducing
the risk of injury to the bile duct orcontralateral vascular
structures. It must be empha-sized, however, that this approach is
not appropriatefor tumors that encroach on the hilus since the
resec-tion margin will be compromised.
When hilar dissection is used, it is not necessaryto attempt to
encircle and divide the right hepaticduct. Such dissection risks
injury to the biliary con-fluence. Rather, control of the right
hepatic duct canbe obtained during parenchymal transection, whichis
safer.
Figure 820. Small veins draining posteriorly from the liver into
theinferior vena cava are carefully dissected and divided from the
cau-date process to the hepatic venous confluence. This allows full
mobi-lization of the right lobe of the liver. (Reprinted with
permission fromBlumgart LH. Liver resectionliver and biliary
tumours. In: BlumgartLH, editor. Surgery of the liver and biliary
tract. 2nd ed. Edinburgh(UK): Churchill Livingstone; 1994. p.
1508.)
Figure 821. Extrahepatic dissection within theporta hepatis for
a right hepatectomy. A, The cys-tic and hilar plates are lowered to
expose the rightpedicle. B, The peritoneum overlying the commonbile
duct is incised. The cystic duct and cysticartery are ligated and
divided. A tie has been lefton the cystic duct for retraction. C,
The righthepatic duct is dissected. D, The right hepaticduct has
been ligated and divided withabsorbable suture. The right hepatic
artery is dis-sected, ligated, and divided. E, The right portalvein
is dissected, doubly clamped, and divided.The branch from the
caudate process is eitherdivided prior to this or avoided. F, The
proximalend of the portal vein is oversewn with vascularsuture.
(Reprinted with permission from BlumgartLH. Liver resectionliver
and biliary tumours. In:Blumgart LH, editor. Surgery of the liver
and bil-iary tract. 2nd ed. Edinburgh [UK]: Churchill Liv-ingstone;
1994. p. 15067.)
-
Techniques of Hepatic Resection 175
Figure 822. Isolation of the portal pedicles. A, The main
portalpedicles are seen in this cutaway drawing. B, The lines of
incision fora pedicle ligation are shown. For a right hepatic
resection, twoapproaches are used: A hepatotomy is made in the
caudate processparallel to and 5 mm lateral to the inferior vena
cava (1); in the firstmethod, the full thickness of the caudate
process is divided.The sec-ond hepatotomy is made in the center of
the bed of the gallbladder,near the hilus (2); the second method is
an anterior incision in frontof the hilum (3), extending up the
gallbladder bed (2). For left hepa-tectomies, a similar incision
(2, 3) can be used although it is ofteneasier to dissect the main
sheath at the base of the caudate lobe(GB = gallbladder). C, During
a right hepatectomy, the right portalpedicle is isolated by finger
dissection, the finger being passedthrough a hepatotomy in the
caudate process and brought out in thegallbladder fossa (see text).
D, A vessel loop is passed about theright portal pedicle, which is
strongly retracted toward the patientsleft. The left portal pedicle
is protected. E, A stapling device is usedto facilitate division of
the right portal pedicle. Note that the point ofdivision is well
away from the left pedicular structure.
A B
C
E
D
-
176 HEPATOBILIARY CANCER
With the inflow controlled, attention is thenturned to the
control of the right hepatic vein (Fig.823). During the initial
mobilization, the posteriorveins draining directly into the liver
and the liga-ment along the lateral aspect of the IVC were
ligatedand divided. Any remaining branches are ligated anddivided
(Fig. 824). The right hepatic vein is nowvisible, but complete
control requires further dissec-tion above the liver (Fig. 825).
Avascular tissuebetween the right and middle hepatic veins must
bedivided. The right vein can now be encircled anddivided with a
vascular stapler, or it can be clamped(Fig. 826), divided, and
oversewn (Figs. 827 and828). The right vein may also be controlled
anddivided within the substance of the liver. Extrahep-atic control
is preferable if possible. In some cases,
the middle hepatic vein must be sacrificed, but it isusually
taken within the liver parenchyma. The lineof transection may be to
the left or right of this vein,depending on the situation. If the
middle vein isdivided, venous drainage of segment IV will be
pro-vided by the umbilical vein. The surgeon must beprepared to
extend the incision into the right chest orto perform a sternotomy
should there be difficulty incontrolling the hepatic veins or vena
cava.
At this point, parenchymal division is begun. Theline of
transection along the principal plane ismarked with electrocautery
and then cut with scis-sors. Stay sutures of 0 chromic catgut are
placed oneither side of the plane of transection and used
fortraction, separation, and elevation as dissection pro-ceeds. A
Kelly clamp is used to crush the liverparenchyma, and exposed
vessels are controlledwith clips, ligatures, or the vascular
stapler (Fig.829). Although the liver can tolerate warmischemia for
up to 60 minutes, the authors use inter-mittent portal-triad
clamping during the parenchy-mal transection phase, mainly to allow
decompres-sion of the gut. After the specimen is removed, theraw
surface of the remnant liver is carefully exam-ined for hemostasis
and bile leaks. The argon beamcoagulator is excellent for
controlling raw surfaceoozing. Biliary leaks should be clipped or
suture lig-ated. The retroperitoneal surfaces should also
beexamined carefully for hemostasis, and the argonbeam should be
used where necessary.
Extended Right Hepatectomy:Right Hepatic Lobectomy
or Right TrisegmentectomyThe additional removal of segment IV
during righthepatectomy (normally removing segments V, VI,VII, and
VIII) constitutes an extended right hepatec-tomy. The initial steps
are similar to those of the righthepatectomy, with mobilization
being performed andthe right hepatic vein and the right portal
pediclebeing exposed and divided. The bridge of tissue con-necting
segments III and IV is divided with electro-cautery after passing a
Kocher director beneath,revealing the lower part of the umbilical
fissure. Insome patients, this tissue consists of an avascular
lig-ament; in others, it consists of hepatic parenchyma.
Figure 823. Isolation of the right hepatic vein. The right liver
hasbeen fully mobilized and the inferior vena cava has been
completelyexposed up to the right hepatic vein. A, Vascular clamps
have beenapplied on either side of the hepatic veins. B, Two clamps
have beenapplied on the caval side and one on the liver side. C,
The righthepatic vein has been divided and the stump has been
oversewnwith vascular suture. (Reprinted with permission from
Blumgart LH.Liver resectionliver and biliary tumours. In: Blumgart
LH, editor.Surgery of the liver and biliary tract. 2nd ed.
Edinburgh [UK]:Churchill Livingstone; 1994. p. 1509.)
-
Techniques of Hepatic Resection 177
Figure 825. After division of the small draining veins
posteriorly, the right hepatic vein isvisible (arrow) but requires
further dissection for isolation.
Figure 824. The right lobe of the liver has been mobilized and
turned toward the left. Thevena cava is exposed. Retrohepatic veins
are dissected and controlled, commencing frombelow and progressing
upward.
-
178 HEPATOBILIARY CANCER
The ligamentum teres can been seen running in theumbilical
fissure and joining the left portal vein.
The right pedicle is controlled intra- or extrahep-atically as
above. The recurrent vessels from theumbilical fissure to segment
IV are divided andsuture ligated (Figs. 830 and 831). If the tumor
isnear the fissure, these recurrent vessels should bedivided from
within the umbilical fissure, takingcare to avoid injury to the
main left pedicle. Alter-natively, they may be ligated and divided
duringparenchymal transection. The right and middlehepatic veins
are divided as described above.
The liver is transected just to the right of the fal-ciform
ligament, using the standard parenchymal
crushing technique. The middle hepatic vein must beligated, and
it is encountered as dissection pro-gresses deeper in the upper
portion of the liver; itcan be ligated or stapled at this point.
During thisportion of the procedure, care must be taken to
avoidinjury to the left hepatic vein, which usually entersthe
middle hepatic vein.
Left Hepatectomy
Removal of segments II, III, and IV constitutes a
lefthepatectomy. The left liver is mobilized in standardfashion as
described above, with division of the lefttriangular ligament. Our
preference is to perform
Figure 826. A, The right hepatic vein isexposed for subsequent
division. A Kellyclamp passes easily between the right andmiddle
hepatic veins on the anterior surfaceof the inferior vena cava. B,
The Endo-GIAvascular stapler is used to divide the righthepatic
vein.
A
B
-
Techniques of Hepatic Resection 179
Figure 828. The black arrow indicates the divided right hepatic
staple line. A clamp hasbeen passed beneath the common trunk of the
middle and left hepatic veins (white arrow).
Figure 827. The right hepatic vein may be divided between clamps
and then oversewn.Note that the inferior vena cava has been
completely freed from the posterior surface ofthe liver.
-
180 HEPATOBILIARY CANCER
inflow control outside the liver, at the base of theumbilical
fissure (Fig. 832). The hilar plate is low-ered, and the left
hepatic artery is identified, ligated,
and divided (see Fig. 821). Within the gastrohep-atic ligament,
an accessory or replaced left hepaticartery may be found and should
be divided and lig-
Figure 829. A crushing technique is used to divide the liver
tissues. Vessels are exposedfor future ligation or clipping.
Figure 830. A, Recurrent vessels from the umbilical fissure to
segment IV are divided and ligated withsuture just to the right of
the falciform ligament. The recurrent vessels may also be divided
from within theumbilical fissure, taking care to avoid injuring the
main left pedicle. B, Division of the liver parenchyma pro-ceeds
toward the inferior vena cava, to the right of the falciform
ligament. (Reprinted with permission fromBlumgart LH. Liver
resectionliver and biliary tumours. In: Blumgart LH, editor.
Surgery of the liver andbiliary tract, 2nd ed. Edinburgh [UK]:
Churchill Livingstone; 1994. p. 1514.)
A B
-
Techniques of Hepatic Resection 181
Figure 831. During an extended right hepatic lobectomy (right
trisegmentectomy), feedback ves-sels arising from the umbilical
fissure and progressing to segment IV are divided between clamps.
Thedissection proceeds backward just to the right of the falciform
ligament. The arrow indicates the liga-mentum teres and the
falciform ligament. Segment IV is marked.
Figure 832. The portal anatomy of the umbilical fissure. A,
Divi-sion here devascularizes the entire left liver, including the
caudatelobe. B, Division above the caudate branch will preserve the
caudateblood supply and devascularize segments II, III, and IV. C,
The pointof division to divide the segment II pedicle. D, The point
of division todivide the segment III pedicle. The pedicles to IVa
and IVb branch offthe right side of the left portal triad with the
umbilical fissure and canbe controlled here for an extended left
lobectomy. (Reprinted withpermission from Blumgart LH. Liver
resectionliver and biliarytumours. In: Blumgart LH, editor. Surgery
of the liver and biliary tract,2nd ed. Edinburgh [UK]: Churchill
Livingstone; 1994. p. 1518.)
ated. The portal vein is identified at the base of theumbilical
fissure. Care must be taken to preserve theprincipal caudate
branch, which usually arises fromthe left portal vein. If the
caudate lobe is to be pre-served, then the portal vein is
controlled beyond theorigin of this branch.
The left bile duct has a long extrahepatic courseand can be
identified beneath the quadrate lobebehind the portal vein and
divided at the umbilicalfissure or (as with a right hepatectomy)
controlledfrom within the hepatic parenchyma.
The left and middle hepatic veins are controlledafter mobilizing
the left lobe and lifting it up anteri-orly and to the right (Fig.
833). The gastrohepaticligament is divided, and dissection
continues at theligamentum venosum, which is divided as it
entersthe left hepatic vein. Control of the veins is obtainedby
careful dissection from above and below the liver;a passage is
developed from just to the right of themiddle hepatic vein from
above and the superiorborder of the caudate process from below. The
veinsare clamped, ligated, and divided. The middle andleft hepatic
veins most often enter the IVC as a sin-gle trunk but may be
independent in some cases.
-
182 HEPATOBILIARY CANCER
Stay sutures are placed along either side of the prin-cipal
plane (along the line of demarcation) (Fig.834), the line of
transection is marked, and theparenchyma is divided as described
above.
Left Lateral Segmentectomy:Left Lobectomy
Removal of segments II and III constitute a left
lateralsegmentectomy. The bridge of tissue overlying theumbilical
fissure is divided, and the left triangular lig-ament is divided,
mobilizing the left lobe. Within theumbilical fissure, the pedicles
to segments II and IIIcan be dissected and controlled individually
(see Fig.832). For tumors lying close to the fissure, thisapproach
is important. An alternate approach forperipheral lesions is
splitting the liver anteroposteri-orly just to the left of the
ligamentum teres and thefalciform ligament. The pedicles to
segments II andIII can then be divided serially during
parenchymaltransection. The hepatic vein can be controlled and
divided within the liver substance posteriorly, withouthaving to
dissect the vein extrahepatically. However,if the tumor is close to
the junction of the left andmiddle hepatic veins, extrahepatic
dissection and con-trol of the vein should be performed.
Extended Left Hepatectomy:Left Trisegmentectomy
An extended left hepatectomy involves the removalof segments V
and VIII in addition to a left hepatec-tomy. This is among the most
challenging of hepaticresections and is used when tumors involving
theleft liver extend into the anterior sector of the rightlobe or
when the anterior sector is the site of addi-tional metastatic
disease. The difficulty of the pro-cedure lies in defining the
plane of transection,which is horizontal rather than vertical and
parallelbut anterior to the right scissura (Figs. 835 and836).
Injury to the pedicle supplying the posteriorsector or to the right
hepatic vein is the major con-cern and must be avoided.
Dissection begins with division of the falciformligament to the
hepatic veins and IVC. Completemobilization follows, including
division of the lefttriangular ligament as well as mobilization of
theright side. The presence of a large accessory righthepatic vein
is a potentially important finding, espe-cially for tumors
encroaching on the main righthepatic vein, and may allow sacrifice
of the mainright hepatic vein if necessary for tumor
clearance.Dissection proceeds as with a left hepatectomy, withthe
liver rotated right and the portal triad approachedfrom the left
side. If the caudate lobe is to beresected as well, the left
hepatic artery and leftbranch of the portal vein should be ligated
close totheir origins to disconnect the blood supply to thecaudate
lobe and segments II and III. If segment I isnot to be resected,
the left portal triad is taken at thebase of the umbilical fissure,
preserving the bloodsupply to the caudate lobe.
After the inflow has been controlled, the outflowis controlled,
and dissection of the left hepatic veinand IVC is performed. It is
advantageous to controlthe middle and left hepatic veins
extrahepatically forthis procedure because it reduces blood loss
duringparenchymal transection.
Figure 833. Approach to the left and middle hepatic veins.
Theleft lobe is completely mobilized and lifted anterior and to the
right(white arrow). The gastrohepatic ligament is divided, and
dissectioncontinues at the ligamentum venosum, which is divided as
it entersthe hepatic vein. A passage is developed from just to the
right of themiddle hepatic vein from above and the superior border
of the cau-date lobe (A to B). The veins are clamped, ligated, and
divided. IVC= inferior vena cava; MHV = middle hepatic vein; LHV =
left hepaticvein; GB = gallbladder. (Reprinted with permission from
BlumgartLH. Liver resectionliver and biliary tumours. In: Blumgart
LH, edi-tor. Surgery of the liver and biliary tract, 2nd ed.
Edinburgh [UK]:Churchill Livingstone; 1994. p. 1523.)
-
Techniques of Hepatic Resection 183
The greatest challenge to extended left resec-tions lies in
defining the plane of transectionahorizontal plane anterior and
parallel to the rightscissura, just lateral to the gallbladder
fossa.Another way of describing this plane is as a hori-zontal
plane extending from the anterior border ofthe right hepatic vein
to an area to the right of thegallbladder fossa. The plane can be
more clearlydefined if the right anterior sectoral pedicle is
con-trolled, as this will demarcate the line of dissection.This can
only be done when the tumor is away fromthe main right portal
pedicle; otherwise, the surgi-cal margin may be compromised.
Using intermittent portal-triad occlusion, theparenchyma is
divided from the inferior surfaceupward and from right to left in a
horizontal plane. Byrotating the fully mobilized liver clockwise,
the hori-zontal plane of transection is converted to a
verticalplane, easing the dissection. The dissection
proceedsanterior to the right posterior pedicle (when the liveris
rotated, the dissection will be just medial to thepedicle). The
line of transection is often dictated bythe tumor. Large tumors in
proximity to the posteriorpedicle or the right hepatic vein will
limit the possiblesize of the resection margin since these
structures
must be preserved. Such tumors often produce afibrous zone of
atrophic parenchyma peripherally,however, and dissection will
proceed in this plane.
Although challenging, extended left resectionscan be done
safely, with mortality rates only slightlyhigher than those of
other types of resection. Post-operative morbidity is significant,
however, with bil-iary leak and abdominal abscess being the
majorcomplications.14 Removal of all but the posteriorsector may
also result in significant postoperativeliver dysfunction, and
patients are more likely tohave ascites postoperatively.
Caudate Lobe Resection:Segment I Resection
The caudate lobe is most commonly removed enbloc as part of a
major hepatic resection to achievetumor clearance and (less
commonly) as an isolatedcaudate resection. Damage to the middle or
lefthepatic veins is a major risk of isolated caudatelobectomy
(Fig. 837). The caudate lobe may beapproached mainly from the right
or left althoughdissection from both sides is necessary most
often(see Fig. 837). An approach from the right side may
Figure 834. During a left hepatic resection, the left hepatic
artery and left branch of the portal veinare controlled. The line
of division between the devascularized left liver and the right
liver is clearlyseen. Segments II, III, and IV have been
devascularized.
-
184 HEPATOBILIARY CANCER
Figure 836. Extended left hepatectomy. The liver parenchyma
isdivided just anterior to the lower limit of the right scissura.
The ante-rior sectional pedicle (small arrow) may be taken within
the liver sub-stance. (Reprinted with permission from Blumgart LH.
Liver resec-tionliver and biliary tumours In: Blumgart LH, editor.
Surgery of theliver and biliary tract. 2nd ed. Edinburgh [UK]:
Churchill Livingstone;1994. p. 1516.)
be necessary for bulky lesions that prevent accessfrom the left
or when the caudate lobe is to beremoved en bloc with the right
liver. After divisionof the gastrohepatic omentum and the
ligamentousattachments from the caudate lobe to the IVC (Fig.838),
the right liver is mobilized as above, and theposteriorly draining
veins along the entire retrohep-atic cava are divided. The liver is
rotated, and thedissection proceeds along the anterior surface of
theIVC, lateral to medial, allowing identification andcontrol of
the caudate veins. Some of these veinsmay not be easily controlled
from the right side. Theattachments of the caudate lobe to the IVC
must also
be divided. The branches to segment I from the leftportal vein
and left hepatic artery are then dissected(Fig. 839) close to the
base of the umbilical fissurejust before the entry of the left
portal triad, wherethey are ligated and divided. The caudate lobe
isthen separated from its attachment to the right liver,under
inflow occlusion.
A principal approach from the left side may bepossible with
smaller tumors or when the caudatelobe is to be removed en bloc
with the left liver. Aswith a left hepatectomy, the left liver is
mobilized.The left lateral margin of segment I is freed by
divid-ing the fibrous attachment posteriorly to the IVCand
diaphragm, exposing the veins draining the cau-date lobe into the
cava (Fig. 840). The approach tothe inflow vessels is the same.
An alternative approach to isolated segment Iresection has been
described and involves mobiliza-
Figure 835. Extended left hepatectomy. The line of
transection,as indicated, is horizontal and parallel to the right
scissura. Dissec-tion proceeds with the liver rotated right and the
portal triadapproached from the left. If the caudate lobe is to be
preserved, theportal vein is divided beyond the caudate branch. If
the caudate lobeis to be resected, the left hepatic artery and left
branch of the portalvein are divided close to their origins
(inset). The line of transectionlies along the ligamentum venosum,
(the base of the quadrate lobeand hilus), and curves to the right
into the right scissura lateral to thegallbladder fossa. (Reprinted
with permission from Blumgart LH.Liver resectionliver and biliary
tumours. In: Blumgart LH, editor.Surgery of the liver and biliary
tract. 2nd ed. Edinburgh [UK]:Churchill Livingstone; 1994. p.
1516.)
-
Techniques of Hepatic Resection 185
tion of the caudate lobe as described above (Fig.841), followed
by splitting of the hepaticparenchyma along the principal plane.
This providesaccess to the right border of the caudate lobe,
whichcan be disconnected under direct vision below themiddle
hepatic vein and may thus prevent uncon-trolled bleeding. The right
and left hemilivers aresplit but not resected.
Segmental Resection
Because each segment is defined by an anatomicstructure with its
own pedicles, each segment can beresected separately (Figs. 842 and
843) or resectedwith other segments as part of a larger
resection.15
The following describes some of the more commonlyperformed
anatomic sublobar hepatic resections.
Figure 837. Caudate lobe resection. Thecaudate lobe may be
approached from the rightor left although dissection from both
sides isoften necessary. The inflow to the caudate lobehas been
divided (above), and the caudateveins are now controlled in turn.
(Reprinted withpermission from Blumgart LH. Liver resectionfor
benign disease and for liver and biliarytumors. In: Blumgart LH,
Fong Y, editors.Surgery of the liver and biliary tract. 3rd
ed.Edinburgh [UK]: Churchill Livingstone, 2000.)
Figure 838. Caudate lobe resection. The gastrohepatic omentum
and the ligamentous attachmentsof the caudate lobe to the inferior
vena cava are divided (small arrow), and the posteriorly
drainingveins along the retrohepatic cava (large arrow) are
divided.
-
Figure 840. Caudate lobe resection. Veins draining the caudate
lobe posteriorly are exposed bymobilizing the left lateral margin
of segment I, dividing the fibrous attachment posteriorly to the
inferiorvena cava.
186 HEPATOBILIARY CANCER
Figure 839. Caudate lobe resection. Branches to segment I from
the portal vein and left hepaticartery are dissected close to the
base of the umbilical fissure. The caudate lobe is retracted to the
leftwith forceps.
-
Techniques of Hepatic Resection 187
Right Posterior Sectorectomy (Segments VI and VII)
Removal of segments VI and VII constitutes a poste-rior
sectorectomy. The procedure begins with the fullmobilization of the
right lobe of the liver from itsdiaphragmatic attachment and the
division of the pos-terior draining veins, as described above.
Dissectionof the right vein will permit rapid repair or
removalshould it be damaged during dissection. The right por-tal
pedicle is exposed, and the anterior and posteriorbranches are
identified. The posterior pedicle isclamped, and the line of
demarcation is evident. Thepedicle may be divided, and parenchymal
dissectionmay be performed in standard fashion. The line
oftransection is horizontal and posterior to the righthepatic vein.
However, the right vein may be sacri-ficed during this procedure
since the anterior sectorwill be adequately drained by the middle
hepatic vein.
Segment IV Resection
Segment IV is divided into a posterosuperior por-tion (IVa) and
an anteroinferior portion (IVb).Resection can include either
portion or both por-tions. The left branches of the portal vein
andhepatic artery supply the inflow to segment IV. Themiddle
hepatic vein provides venous drainage viamedial branches. The
umbilical hepatic vein belowthe falciform ligament provides
additional drainageand may drain into the middle or left veins. The
firstmaneuver is division, with electrocautery of thebridge of
liver tissue overlying the umbilical fis-sure. The hilar plate is
lowered. Branches from theumbilical portion of the left portal
vein, left hepaticartery, and bile duct are the principal inflow to
seg-ment IV. The parenchyma is divided with two inci-sions. One
incision is just to the right of the liga-mentum teres, with
control of the segment IVfeedback vessels as described for extended
right
Figure 841. Caudate lobe resection. An alternative approach
tosegment I resection involves splitting the hepatic parenchyma
alongthe principal plane (black arrow).This provides access to the
right bor-der of the caudate lobe, which can be disconnected under
direct visionbelow the middle hepatic vein (MHV). The caudate lobe
has beendetached from the inferior vena cava (IVC). (Reprinted with
permissionfrom Blumgart LH. Liver resection for benign disease and
for liver andbiliary tumors. In: Blumgart LH, Fong Y, editors.
Surgery of the liver andbiliary tract. 3rd ed. Edinburgh [UK]:
Churchill Livingstone, 2000.)
Figure 842. Segment III resection. The ligamentum teres is
indi-cated by the arrow. Segment III has been excised, leaving
segmentII fully vascularized.
-
188 HEPATOBILIARY CANCER
hepatectomy. The initial division of these vesselswill delineate
the extent of the resection. The otherincision is for division in
the principal plane backtoward the IVC. The middle hepatic vein
will beencountered; it may be preserved or taken, depend-ing on the
situation (Fig. 844).
Central Resection
Removal of segments IV, V, and VIII (segment IVplus an anterior
sectorectomy) constitutes a centralresection. This seemingly
complex procedure isused to maximize the amount of remnant liver
left
Figure 844. Resection of segment IVb for metastatic colorectal
cancer.
Figure 843. Segmental liver resection. The falciform ligament is
indicated. Segment IV remainsintact, as does segment II. Segment
III has been precisely removed, as has segment V.
-
Techniques of Hepatic Resection 189
after resection as both the posterior sector and theleft lateral
segment will remain. In essence, theapproach to a central resection
is similar to theapproach to a posterior sectorectomy and to a
leftlateral segmentectomy, except that the posteriorsector and the
left lateral segment are preservedrather than removed. The liver is
fully mobilized,with the posterior draining veins ligated. A
Pringlemaneuver is performed. The right anterior and pos-terior
sectoral portal triads are identified, and theanterior pedicle is
clamped. Transection is per-formed with an intermittent Pringle
maneuver, care-fully preserving the right posterior pedicle and
theright hepatic vein. Segment IV is devascularizedand resected as
described above, with dissection justto the right of the umbilical
fissure. The middlehepatic vein must be taken. Initial exposure of
themiddle vein can be achieved as would be done for aleft
hepatectomy. A vascular clamp may be used toocclude the vein during
parenchymal transection,and the vein may be divided within the
liver duringthe resection.
Wedge Resections
Wedge resections have a higher incidence of posi-tive margins
and greater blood loss and shouldtherefore be avoided in most
cases. However, theymay be appropriate in selected cases.3,16 Small
veryperipheral lesions can be safely excised with ade-quate
margins, using an intermittent Pringle maneu-ver. Isolated lesions
close to the surface can be sim-ilarly excised. After dissection of
the porta hepatisand placement of an umbilical tape, division of
thefalciform, and mobilization of the liver, IOUS isperformed. This
allows confirmation of the lesion,identification of other lesions,
and definition of therelationship of the lesion to the major
vascularstructures. Using electrocautery, an adequate mar-gin of
excision is drawn around the lesion. Staysutures are applied on
either side of the lesion andwithin the area of excision.
Parenchymal dissectionis performed in standard fashion, using a
crushingtechnique. Extra care must be taken to ensure thatthe
normal parenchyma does not fracture aroundthe tumor during
manipulation and that adequatemargins are maintained at all
times.
Resection for Hilar Cholangiocarcinomaand Gallbladder Cancer
Tumors of the proximal biliary tree often invade theadjacent
hepatic parenchyma or vascular structureswithin the porta hepatis
and frequently require par-tial hepatectomy to achieve negative
margins.1719
Involvement of the portal-vein branch on the side ofthe tumor is
not uncommon, and this demands that aconcomitant partial
hepatectomy be performed. Pre-operatively, this may be seen on
imaging studies andis highly suggested by the presence of lobar
atrophy.
Once distant disease has been excluded, full mobi-lization of
the duodenum is performed, dividing thecommon bile duct just above
the duodenum. For hilarcholangiocarcinoma, the gallbladder is taken
down butleft attached to the bile duct; however, this cannot bedone
in patients with gallbladder cancer. The hilarplate is lowered. The
transected bile duct is elevated,and the lymphatic tissue within
the porta hepatis isdissected free and taken with the specimen.
Elevationof the ductal structures allows dissection posterior tothe
tumor and is the only way to assess for vascularinvasion. Palpation
of the tumor will help determineits extent within the bile duct and
whether resection isfeasible. For example, a tumor that involves
the rightbranch of the portal vein or that invades the right
liverwill require a right hepatectomy; however, this is notfeasible
if the tumor also extends well up into the lefthepatic duct,
precluding a negative resection margin.Once it is determined that
the vasculature is free andthat complete tumor clearance can be
achieved, resec-tion is performed as above, with extrahepatic
controlof the inflow and outflow. It is important to
confirmnegative margins intraoperatively with
frozen-sectionhistology. If positive, an additional length of duct
maybe resected. Also, tumor involvement of the caudateduct orifice
demands a concomitant resection of thecaudate lobe, which is always
required for tumorsinvolving the left hepatic duct. In cases of
tumoradherence to the portal venous confluence, resectionwith
reconstruction of the portal vein may be possible.
Cryoassisted Resection
Cryoassisted resection is a technique that may be use-ful in
selected patients for achieving a complete tumor
-
190 HEPATOBILIARY CANCER
resection with maximal sparing of uninvolved hepaticparenchyma.
This would be useful in the case of smalllesions deep within the
parenchyma that would neces-sitate the removal of a large amount of
normal hepatictissue or for patients with underlying liver
diseasewho would not tolerate a major resection.
Intraoperative ultrasound is used to define thelesion, and the
cryoprobe is inserted into the tumor,using a modified Seldinger
technique. The probe iscooled to 180, freezing the tumor until a 1-
to 2-cmmargin of uninvolved tissue is frozen. The advancingice ball
can be seen by US. The tumor and the marginof normal parenchyma are
then excised, dividing anypedicles or hepatic vein branches and
using the cry-oprobe as a handle to aid the resection. The
applica-bility of this technique is limited to tumors that are
lessthan 5 cm in size and that do not involve major vascu-lar
structures. In the appropriate setting, however, thisis a
reasonable approach. In addition, freezing thetumor and a margin of
parenchyma eliminates fractur-ing at the tumor-margin interface, a
common cause ofpositive histologic margins during wedge resection
ofhard tumors such as colorectal metastases.16
POSTOPERATIVE CARE
Closure of the abdominal wall is done in continuousfashion in
one or two layers with absorbablemonofilament (#1 PDS, Ethicon).
Skin is closedwith staples or in subcuticular fashion. Drains
arenot necessary for routine hepatic resection withoutconcomitant
biliary resection and reconstruction.Indeed, a prospective
randomized study of patientsundergoing liver resection showed an
increasedcomplication rate in patients in whom drains wereplaced
compared to those without drains.20
Patients are kept in the recovery room for approx-imately 1 day.
The large-bore central lines arechanged to triple-lumen catheters
prior to discharge tothe floor. This facilitates electrolyte
replacement ifnecessary. Intravenous fluids should include
phos-phorous as liver regeneration requires large amountsof
high-energy phosphates and as serum phosphorouslevels can drop
quite low without supplementation. Infact, one of the signs of
appropriate liver regenerationis a transient drop in serum
phosphate levels, begin-ning 24 to 48 hours postoperatively. For
large-volume
liver resections, electrolytes, blood count, and coagu-lation
profile are checked postoperatively, then dailyfor 3 to 4 days.
Particular attention is paid to the pro-thrombin time (PT). The
threshold for administeringblood products varies with the clinical
situation andthe surgeon. In general, packed red blood cells
areadministered if the hemoglobin falls to 8 mg/dL orlower, and
fresh frozen plasma is given if the PT isgreater than 17 seconds.
Bleeding is the principalconcern in the immediate postoperative
period, andany significant drop in the hemoglobin or any
hemo-dynamic instability should prompt a return to theoperating
room. Patients are transferred to the wardon the first
postoperative day and are encouraged toambulate three times per
day. Postoperative pain con-trol is achieved with
patient-controlled analgesia.Understanding the decreased clearance
of hepaticallymetabolized drugs is extremely important in
selectingmedication for pain control as small doses may
linger.Clear liquids with a rapid advancement of diet arebegun on
or around postoperative day 3 unless a bil-iary-enteric anastomosis
has been performed. Periph-eral edema is common after major hepatic
resectionand may be treated with spironolactone. Unexplainedfever
or rising bilirubin with normalization of otherhepatic function
parameters suggests an intra-abdom-inal bile collection and should
be investigated with aCT scan. Such collections usually resolve
after a fewdays with percutaneously placed drains; reoperationis
rarely necessary. The median length of stay formajor hepatic
resection is 8 days.
REFERENCES1. Ochiai T, Takayama T, Inoue K, et al. Hepatic
resection
with and without surgical margins for hepatocellularcarcinoma in
patients with impaired liver function.Hepatogastroenterology
1999;46:18859.
2. Fong Y, Cohen J, Fortner J, et al. Liver resection for
col-orectal metastases. J Clin Oncol 1997;15:93846.
3. DeMatteo RP, Palese C, Jarnagin WR, et al. Anatomicsegmental
hepatic resection is superior to wedgeresection as an oncologic
operation for colorectal livermetastases. J Gastrointest Surg
2000;4:17884.
4. Melendez JA, Arslan V, Fischer ME, et al.
Perioperativeoutcomes of major hepatic resections under low
cen-tral venous pressure anesthesia: blood loss, bloodtransfusion,
and the risk of postoperative renal dys-function. J Am Coll Surg
1998;187:6205.
5. Belghiti J, Noun R, Zante E, et al. Portal triad clamping
-
Techniques of Hepatic Resection 191
or hepatic vascular exclusion for major liver resec-tion. A
controlled study. Ann Surg 1996;224:15561.
6. Couinaud C. Bases anatomique des hepateccomiesgauche et
droite reglees. J Chir 1954;70:92266.
7. Couinaud C. Etudes anatomiques et chirurgicales.Mason
1957;4009.
8. Launois B, Jamieson GG. The importance of Glissonscapsule and
its sheaths in the intrahepatic approachto resection of the liver.
Surg Gynecol Obstet 1992;174:710.
9. Starzl TE, Iwatsuki S, Shaw BW Jr, et al. Left
hepatictrisegmentectomy. Surg Gynecol Obstet 1982;155:217.
10. Capussotti L, Polastri R. Operative risks of majorhepatic
resections. Hepatogastroenterology 1998;45:18490.
11. Castaing D, Kunstlinger F, Habib N, Bismuth H.
Intra-operative ultrasonographic study of the liver. Meth-ods and
anatomic results. Am J Surg 1985;149:67682.
12. Jarnagin WR, Bodniewicz J, Dougherty E, et al. Aprospective
analysis of staging laparoscopy inpatients with primary and
secondary hepatobiliarymalignancies. J Gastrointest Surg
2000;4:3443.
13. Launois B, Jamieson GG. The posterior intrahepaticapproach
for hepatectomy or removal of segments ofthe liver. Surg Gynecol
Obstet 1992;174:1558.
14. Povoski SP, Fong Y, Blumgart LH. Extended left hepa-tectomy.
World J Surg 1999;23:128993.
15. Bismuth H, Dennison AR. Segmental liver resection.Adv Surg
1993;26:189208.
16. Polk W, Fong Y, Karpeh M, Blumgart LH. A techniquefor the
use of cryosurgery to assist hepatic resec-tion. J Am Coll Surg
1995;180:1716.
17. Bismuth H, Nakache R, Diamond T. Managementstrategies in
resection for hilar cholangiocarcinoma.Ann Surg 1992;215:318.
18. Burke EC, Jarnagin WR, Hochwald SN, et al.
Hilarcholangiocarcinoma: patterns of spread, the impor-tance of
hepatic resection for curative operation,and a presurgical clinical
staging system. Ann Surg1998;228:38594.
19. Jarnagin WR, Fong Y, Blumgart LH. The current man-agement of
hilar cholangiocarcinoma. Adv Surg1999;33:34573.
20. Fong Y, Brennan M, Brown K, et al. Drainage is unnec-essary
after elective liver resection. Am J Surg1996;171:15862.