Hep Resxn Tech

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.)


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


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.)


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-


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


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


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).


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.)


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.)


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.)


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.


(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


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


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.)


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


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.)


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.


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


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.


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


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.


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.)


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.


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.)


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.


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.


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.


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.


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


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


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.

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