Townsend Courtney M.Jr., Evers B. Mark. Atlas of General Surgical Techniques: Expert Consult

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472 Section VI • Liver

◆ Score the capsule of the liver along the line anatomically consistent with segment VIII.

Ultrasound guidance can be very helpful to deﬁ ne anatomy and to target the lesion

(Figure 44-11).

◆ Perform dissection through the parenchyma of the liver carefully and progressively using

the handheld harmonic dissector. The recently available tissue-coagulating instrument,

based on radio-frequency energy (Habib device), may be substituted for division of

parenchyma but should not be used near major vessels. This instrument is particularly

useful in nonanatomic resections because of its effectiveness in controlling hemorrhage

during the parenchymal incision (see Figure 44-11).

VIII

FIGURE 44 –11

CHAPTER 44 • Segmental Hepatic Resection 473

◆ Using visual inspection, and if necessary ultrasound guidance, identify major intraparenchymal

vascular tributaries and branches, and then clamp, divide, and ligate. Biliary radicals, which

must be ligated individually, are most difﬁ cult to identify at the time of dissection. Failure to

ligate these structures results in postoperative bile leaks (see Figure 44-11). The right and mid-

dle hepatic veins should be identiﬁ ed and remain undisturbed during the dissection.

◆ Perform ultrasound examination intraoperatively to ensure adequate margin of resection in

the case of malignant tumor removal. A 1-cm margin is considered to be adequate, but in

major resections, margins are not typically an issue.

◆ Bring out two 10-mm Jackson-Pratt drains through separate stab wounds on the right side

of the abdomen and place along the divided edge of the liver (Figure 44-12). Some will

advocate taking omentum and placing it in the bed of the resected liver to act as a biologic

seal for the raw edge of the liver parenchyma.

Completed segment VIII resection

FIGURE 44 –12

474 Section VI • Liver

3. CLOSING

◆ Close the abdomen in a standard manner. We favor a horizontal mattress closure (Smead-

Jones) with heavy-gauge absorbable suture.

STEP 4: POSTOPERATIVE CARE

◆ In the ﬁ rst 24 hours after surgery, the primary concern is hemorrhage and the related mea-

sure of coagulation status. These should be monitored by means of serial measurement of

hemoglobin and coagulation factors.

◆ In all major resections, particularly in patients with cirrhosis, one must be vigilant for any

signs of hepatic failure. A particularly ominous ﬁ nding is the progressive rise in bilirubin

level with an enzyme pattern that supports neither obstruction nor parenchymal cell death,

such as transaminase elevations. The most ominous ﬁ nding is a plummeting serum glucose

level, which reﬂ ects the loss of glycogen stores in the liver and by inference the loss of via-

ble liver. Unfortunately, there is little one can do to reverse this pattern of failure. One pos-

sible cause is inadequate remaining liver after resection. This can resolve over time as the

liver regenerates, which it will do to some degree.

◆ One possibly remediable cause of this progressive demise is thrombus formation in the

portal vein. This would seem to be unlikely, because coagulation is typically inadequate in

these patients, but we have seen this phenomenon. It is possible that lysis of this clot may

restore vital ﬂ ow.

◆ Sepsis is particularly metabolically taxing to the liver. In the compromised postoperative

liver, sepsis can be catastrophic. One should monitor and obtain cultures if necessary to

prevent infectious processes from progressing.

◆ Ascites may form, and one must be aware when this phenomenon has occurred and treat as

one would normally treat this entity with careful and judicious use of salt-containing intra-

venous ﬂ uids and with diuresis.

◆ Remove drains if no bile is seen in the efﬂ uent.

CHAPTER 44 • Segmental Hepatic Resection 475

STEP 5: PEARLS AND PITFALLS

◆ As with all such major operative procedures, one must exercise extreme care in patient

selection.

◆ If hemorrhage occurs at any time during the procedure, the liver can be compressed into

the spine or into the right ﬂ ank to gain control, and another capable surgeon can be called

for assistance.

◆ Before dividing any of the major vascular structures, stop and reconﬁ rm that the proper

structure is being divided.

◆ If ascites forms and the drains are still in place, excessive electrolyte and ﬂ uid loss can

occur through actively draining liters of ﬂ uid per day. In this setting, the drains (assum-

ing they are not bile tinged) should be removed, and the skin overlying the drain tract

should be sutured.

SELECTED REFERENCES

1. Blumgart LH, Belghiti J: Liver resection for benign disease and for liver and biliary tumors. In Blumgart LH

(ed): Surgery of the Liver, Biliary Tract and Pancreas, 4th ed. Philadelphia, Saunders, 2007, pp 1341-1388.

2. Liu CL, Fan, ST, Cheung ST, et al: Anterior approach versus conventional approach right hepatic resection

for large hepatocellular carcinoma: A prospective randomized controlled study. Ann Surg 2006;244:

194-203.

3. Nanashima A, Sumida Y, Abo T, et al: Anatomic resection of segments 5, 6 and 7 of liver for hepatocellu-

lar carcinoma: Prior control of right paramedian Glisson. Hepatogastroenterology 2008;55:1077-1080.

4. Shirabe K, Shimada M, Gio T, et al: Postoperative liver failure after major hepatic resection for hepatocel-

lular carcinoma in the modern era with special reference to remnant liver volume. J Am Coll Surg

1999;188:304-309.

476

STEP 1: SURGICAL ANATOMY

◆ The liver is suspended in the right upper quadrant by avascular ligamentous attachments.

The falciform ligament is oriented vertically and suspends the liver from the anterior abdom-

inal wall at its inferior limit to the diaphragm, just anterior to the vena cava. The left and

right triangular ligaments extend in a transverse direction beginning on the lateral borders of

both the left and right liver, coursing along the diaphragm, and terminating at the vena cava,

where they join the superior extent of the falciform ligament. The triangular ligaments are

composed of both anterior and posterior leaﬂ ets.

◆ The liver appears on gross examination to be composed of two discrete lobes. Thus there is a

traditional terminology in which the left and right lobes are deﬁ ned by the falciform ligament.

Resection of one of these is termed a left or right lobectomy. This terminology has largely been

replaced by one based on the intraparenchymal vascular and biliary structures.

◆ Based on the intraparenchymal anatomy, the liver is divided into left and right livers, each

composed of four segments. The line of demarcation is located several centimeters to the

right of the falciform ligament and projects in a line, which transects the gallbladder bed

from anterior to posterior (Figure 45-1).

◆ Using the segmental anatomy, the liver is divided into left liver and right liver. The left liver is

served by the left portal vein, left hepatic artery, and left bile duct. It is composed of segments

I, II, III, and IV. Segments II and III represent the traditionally termed left lobe. Segment II is

attached to the left hemidiaphragm by the left triangular ligament, and segment III occupies

the inferior aspect of the left lobe. The boundary between the two extends horizontally,

approximately midway through the left lobe. Segment I, also called the caudate lobe, occupies

the posterior aspect of the liver in the midline. The segment wraps rather like a collar around

the vena cava on its left aspect. This segment is unique for its venous drainage, which is inde-

pendent of the left or middle hepatic veins and is composed of multiple tiny tributaries

between the vena cava and the segment. Segment IV, the quadrate lobe, occupies the area

between the falciform ligament medially and the gallbladder bed laterally (see Figure 45-1).

◆ The right liver is composed of segments V, VI, VII, and VIII. These four are oriented around

a horizontal line transecting the right liver at its mid-portion and similarly by a vertical line

that transects the right liver at its mid-portion. Beginning at the inferomedial segment V, the

segments follow a clockwise direction with VI inferolateral, VII superolateral, and VIII

superomedial (see Figure 45-1).

CHAPTER

Right Hepatectomy

William H. Nealon

CHAPTER 45 • Right Hepatectomy 477

◆ Lymphovascular and biliary structures enter the liver through the hepatoduodenal ligament

that courses between the duodenum into the base of segments IV and V, which is termed

the porta hepatis. The portal triad of microanatomy is matched by the gross anatomic ori-

entation in the hepatoduodenal ligament, composed of hepatic artery, portal vein, and bile

duct. Each structure divides into a left and right branch and then arborizes within the liver

in a pattern deﬁ ned by the segments (see Figure 45-1).

◆ Venous drainage of the liver is primarily located at the superior aspect of the liver in short

structures between the vena cava and the liver. The left, middle, and right hepatic veins

each enter the vena cava within 2 to 4 cm of one another in a coronal orientation. One or

all of these venous elements may be intrahepatic or may have exceedingly short extrahe-

patic components. This anatomic feature raises considerably the risk of uncontrolled hem-

orrhage during dissection and resection (Figure 45-2). In addition to these three venous

structures, there are between 2 and 20 tiny tributaries between the posterior surface of the

liver and the contiguous vena cava. These must be divided to fully mobilize the right liver.

Common bile duct

Hepatic artery

Splenic vein

Portal vein

VII

VIII

IV-B

IV-A

III

FIGURE 45 –1

Falciform ligament

Groove for vena cava

Triangular ligament

Bare area

FIGURE 45 –2

478 Section VI • Liver

STEP 2: PREOPERATIVE CONSIDERATIONS

◆ Due to the magnitude of hepatic surgery, one ﬁ rst consideration is the medical status of the

patient and likely risk of surgery. Thus one must exclude signiﬁ cant coronary, pulmonary,

or renal disease, or age and frailty. Of particular concern in relation to hepatic surgery is the

underlying hepatic function. Because hepatocellular carcinoma is associated with prior hep-

atitis and cirrhosis, one must determine ﬁ rst whether cirrhosis exists and second what level

of function is apparent. Historically, this was measured by examining synthetic and excre-

tory functions and measures of portal hypertension (serum albumin level, coagulation pro-

ﬁ le, serum bilirubin level, ascites, and mental status/serum ammonia). More recently, the

Model for End-Stage Liver Disease (MELD) score was developed as a means of segregating

candidates for liver transplant. This system incorporates prior variables, but has added and

places considerable signiﬁ cance to renal function. Particularly when one anticipates a major

resection, one must establish that sufﬁ cient liver will remain to support life. Unfortunately,

this estimate of “hepatic reserve” is even today an inexact science.

◆ Nutritional status, renal function, degree of ascites, and coagulation abnormalities are all

factors that may be improved by medical management before surgery. Unfortunately, we

have personal experience that such patients may thereby achieve an improved functional

grade but appear to carry a risk that exceeds the risk in patients who have had this impro-

ved functional status without a need for medical manipulation to achieve it.

STEP 3: OPERATIVE STEPS

1. INCISION

◆ Several incisions have been proposed. We favor the inverted L incision, with the option to

extend the incision vertically in the midline for added exposure, as well as extending farther

the horizontal component of the incision either laterally into the right ﬂ ank or across the

midline (Figure 45-3).

◆ Placing self-retaining retractors maximizes the exposure of the right upper abdomen. The

incision should be extended if the operative view is inadequate.

CHAPTER 45 • Right Hepatectomy 479

Common

hepatic artery

Portal vein

Inferior vena cava

Hepatic veins

Gallbladder

Common bile duct

Incision

Lesion

Left lobe

Right lobe

FIGURE 45 –3

480 Section VI • Liver

2. DISSECTION

◆ Inferior to the liver edge, divide the falciform ligament between clamps and tie with heavy

silk suture. Cut the sutures at the caudal divided ligament. Place a hemostat on the uncut

cephalad end of the divided ligament for use in manipulating the liver during dissection.

You will discover the need for a constant balance between retracting the liver cephalad and

retracting caudad. Using this tether, you may restore some caudal exposure while the self-

retaining retractor suspends the liver toward the diaphragm.

◆ Using electrocautery, the ﬁ lmy, avascular falciform ligament is incised beginning at its at-

tachment to the anterior abdominal wall and continuing in a cephalad and dorsal direction

until the point of convergence of this ligament meets the left and right triangular ligaments

(Figure 45-4). The hepatic veins are visualized at the superior extent of this dissection.

Carefully divide the peritoneal surface to clearly deﬁ ne the right and middle hepatic veins.

We favor placing a vessel loop around the right and middle hepatic veins at this juncture

(Figure 45-5).

CHAPTER 45 • Right Hepatectomy 481

Diaphragm

FIGURE 45 –4

FIGURE 45 –5

Encircled middle

hepatic vein

Right hepatic vein