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Acute massive bleeding that fails to respond to nonsurgical maneuvers requires emergency surgery, especially if hypotension is present. The possibility of bleeding from sources other than varices should be eliminated before any surgical procedure. TIPS has significantly reduced the number of patients requiring surgical shunts emergently.

1.The decision to proceed with surgery is made if bleeding continues despite transfusion of five units or more of blood, especially within 24 hours. The risk of death rises dramatically after ten units of blood have been transfused, due to both sepsis and the worsening of cirrhotic coagulopathy from the use of banked blood.

2.Surgery is not advisable in the presence of pneumonia, moderate or severe encephalopathy, severe coagulopathy, alcoholic hepatitis (see II G 1 b), or severe liver failure.

3.Type of surgery performed may be either surgery to decompress the portal venous system or surgery to directly ligate the bleeding varices.

a.Emergency portacaval shunting, although very effective in controlling hemorrhage (over 95% of patients stop bleeding), has a high operative mortality related to the Child's classification of the patient (Table 14-1).

1.The usual procedure performed is an end-to-side portacaval shunt or a mesocaval shunt (see II H).

2.The acute reduction of portal blood flow to the liver after shunting may lead to hepatic failure, accounting for two thirds of the perioperative deaths. Pneumonia, renal failure, and delirium tremens are lethal contributing factors.

b.Ligation of varices (see Figure 14-12), either directly or by esophageal transection using a stapling device, usually stops the bleeding.

1.Ligation is associated with an operative mortality rate of up to 30%.

2.Bleeding recurs within several months in up to 80% of survivors.

3.In most patients, ligation probably offers no advantage over shunt procedures.

G

Elective management of esophageal varices is used when patients are not actively bleeding. The goal of this type of surgery is to prevent rebleeding with its concomitant risk of death.

1.Preoperative evaluation includes the following:

a. Endoscopy is used to prove that the esophageal varices bled.

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FIGURE 14-6 Transjugular intrahepatic portosystemic shunt (TIPS). A, a wire is placed from hepatic vein to portal vein in a transhepatic path; B, a balloon catheter is passed over the wire and inserted into the portal vein; C, the balloon is inflated to dilate the path; D, a stent is expanded to maintain patency of the transhepatic path; and E, once established, portal blood may flow freely into the hepatic vein and IVC.

TABLE 14-1 The Child's Classification for Determining the Operative Risk of a Shunting Procedure in a Patient with Portal Hypertension

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b.Acute alcoholic hepatitis must be excluded.

1.This syndrome presents as liver failure with a diffusely tender liver.

2.Histologically, hepatocyte necrosis is seen with discrete hyaline bodies (Mallory's bodies) in hepatic cells.

3.Liver enzyme levels and liver function improve if the patient survives the acute episode.

4.A liver biopsy should be performed if the diagnosis is in question because the operative mortality rate exceeds 50% when surgery is performed in the presence of alcoholic hepatitis.

c.The Child's classification (Table 14-1) is used to evaluate the operative risk.

d.The patient's portal venous anatomy is determined, verifying the presence of a patent portal vein by the following.

1.Splenic and superior mesenteric arteriography followed by delayed venous-phase imaging is the most accurate method.

2.Doppler ultrasound examination to identify the portal vein and its tributaries and ascertain patency and direction of flow is simple and noninvasive.

3.Splenoportography, the injection of radiopaque dye into the spleen followed by imaging of the portal system, is reserved for specific visualization of the splenic vein.

e.The portal venous pressure can be measured indirectly by measuring the wedged hepatic venous pressure.

2.Type of nonoperative management depends on the surgeon's preference and on the patient's pathologic and physiologic status. The choices are as follows:

a.TIPS (see II E 3 e)

b.Direct occlusion of varices

1.Endoscopic variceal banding or sclerosis (sclerotherapy) is initially effective in up to 80%–90% of patients and has become the principal initial method of management for esophageal varices.

2.Many patients require resclerosis procedures because nothing has been done to lower the portal pressure.

3.A major risk of chronic therapy is esophageal stricture.

H

Shunting procedures are designed to lower the portal venous pressure, thereby decompressing esophageal varices and diminishing their propensity to bleed. Portosystemic shunts may be prophylactic or therapeutic and may be nonselective or selective.

1.Prophylactic shunts are performed on patients with proven varices but prior to any episodes of esophageal variceal bleeding.

a.Only 30%–40% of these patients ultimately bleed from their varices, making 60% of the procedures unnecessary.

b.Nonselective shunts decrease hepatic portal venous flow, increasing the risk of hepatic decompensation.

c.In randomized trials, prophylactic shunts have not improved survival rates. They are currently not recommended.

2.Therapeutic shunts are performed on patients who have had a variceal hemorrhage. Patient survival is principally a function of the Child's classification (Table 14-1) prior to surgery. Long-term survival in the alcoholic patient is principally determined by whether or not the patient continues to abuse alcohol.

3.Nonselective portosystemic shunts decompress the entire portal venous system into the inferior vena cava, lowering portal pressure. The type of shunt used depends partly on surgeon preference and whether the patient is likely to be a candidate for a liver transplant.

a.The end-to-side portacaval shunt (Fig. 14-7) is the shunt procedure most commonly performed.

1.The hepatic end of the portal vein is ligated, and the inferior end of the portal vein is sutured to the inferior vena cava, which results in dramatic lowering of portal pressure and decompression of varices.

2.The rebleeding rate is <5%, but the major problem is that portal flow into the liver is reduced to zero, which increases the risk of encephalopathy and hepatic failure.

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FIGURE 14-7 End-to-side portacaval shunt.

b.The mesocaval shunt is constructed with a large-diameter (16–18 mm) prosthetic vascular graft to connect the superior mesenteric vein to the inferior vena cava (Fig. 14-8). It is the preferred shunt in potential liver transplant recipients.

1.With this shunt and the side-to-side portacaval shunt, the effect on portal blood flow into the liver is unpredictable; as portal pressure falls, portal flow into the liver falls. In fact, blood may flow out of the liver via the portal vein, thereby stealing hepatic arterial flow. Thus, the risk of hepatic failure may be higher than for end-to-side portacaval shunts.

2.The advantage of this shunt is the relative ease of exposing the mesenteric vein and the avoidance of any dissection in the porta hepatis, hence facilitating future transplantation.

3.There are two disadvantages:

a.This shunt uses prosthetic material, which has the potential for infection.

b.There is a somewhat lower long-term patency rate as compared with shunts without prosthetic material.

4.As with all shunts, thrombosis of the shunt returns the patient to a high risk of variceal hemorrhage.

FIGURE 14-8 Inferior vena cava–superior mesenteric vein (mesocaval) shunt.

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FIGURE 14-9 Side-to-side portacaval shunt.

c.The side-to-side portacaval shunt is technically more difficult because a longer length of both veins must be prepared (Fig. 14-9). Its use is reserved for situations in which it is necessary to decompress the liver.

1.In the Budd-Chiari syndrome, this shunt or a mesocaval shunt converts the portal vein into an outflow vessel, replacing the thrombosed hepatic veins.

2.With refractory ascites and variceal hemorrhage, this shunt decompresses the liver and decreases ascites (see II L 1 b).

4.Selective portosystemic shunts decrease the pressure in the gastroesophageal bed only and reduce the risk of gastroesophageal varices by shunting only gastroesophageal venous blood into the systemic circulation. Prospective trials have shown a significant decrease in the incidence of postoperative encephalopathy with the selective shunt as compared with the nonselective shunts. The distal splenorenal (Warren) shunt is most commonly performed (Fig. 1410).

a.In this procedure, the distal end of the splenic vein (i.e., the portion coming directly from the splenic hilum) is anastomosed to the left renal vein, a low-pressure vein. The proximal splenic vein is ligated.

b.The coronary vein, the right gastroepiploic vein, and other collaterals between the portal system and the gastric, pancreatic, and splenic region are ligated.

c.As can be seen from Figure 14-10, portal venous flow into the liver is maintained, thus minimizing the problem of hepatic insufficiency and consequent encephalopathy.

whether the patient continues to consume alcohol. The prognosis for other causes of cirrhosis is not quite as poor, although the trends are the same. The overall statistics for alcoholic cirrhotic patients are as follows:

1.Approximately 15% of alcoholics develop cirrhosis, and 30% of these individuals die within a year of the diagnosis.

2.Approximately 40% (i.e., 13%–70%) of cirrhotic individuals develop bleeding varices, and without definitive treatment, 66% of these individuals die within a year.

FIGURE 14-11 Sugiura procedure: esophageal transection and paraesophagogastric devascularization. (Reprinted with permission from Sugiura M, Futagawa S. Further evaluation of the Sugiura procedure in the treatment of esophageal varices. Arch Surg. 1977;112:1317–1321.)

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FIGURE 14-12 End-to-end anastomosis (EEA). The EEA stapler is introduced, and the esophagus is securely tied over the center rod 2 cm above the gastric junction.

The instrument gap is closed, and the trigger is fired, which completes the simultaneous transection and reanastomosis. (Reprinted with permission from Wexler MJ. Treatment of bleeding esophageal varices by transabdominal esophageal transection with the EEA stapling instrument. Surgery. 1980;88:410.)

a.Approximately 50%–80% of patients die from their first variceal hemorrhage without definitive treatment.

b.Of those patients who survive the initial hemorrhage to bleed a second time, the same proportion will die from their second hemorrhage.

K

Hypersplenism is common in patients with portal hypertension.

1.It should be treated conservatively (i.e., nonoperatively). Approximately half of patients who undergo shunting show improvement of the hypersplenism.

2.Splenectomy should be performed rarely for portal hypertension and variceal hemorrhage.

a.It is associated with a variceal hemorrhage recurrence rate as high as 90%.

b.Sepsis and death may follow splenectomy, especially in children.

c.Indication for splenectomy in a patient with variceal bleeding is radiographic proof of splenic vein thrombosis.

1.This occurs as a result of an obstruction in the vein due to a pancreatic disorder, such as pancreatitis or a