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Objective: The indications for and the results of portosystemic shunts done in the authors' institution since initiation of a liver transplant program 10 years ago were reviewed., Summary Background Data: With the widespread availability of liver transplantation as definitive treatment of chronic liver disease, the role of shunts in the overall management of variceal bleeding needs to be redefined., Methods: Seventy-one variceal bleeders with cirrhosis who received a shunt (82% distal splenorenal shunts) because of sclerotherapy failure or because endoscopic treatment was not indicated were reviewed retrospectively. In 44 patients with well-preserved hepatic reserve, the shunt was used as a long-term bridge to transplantation (shunt group 1). The remaining 27 patients with shunts were not transplant candidates mainly because of uncontrolled alcoholism or advanced age (shunt group 2). Survival of both shunt groups was compared to that of 180 adult patients with a history of variceal bleeding who underwent transplantation soon after referral., Results: Because of their more advanced liver disease, the liver transplant group had a higher operative mortality rate (19%) than did either of the shunt groups (5% and 7%, respectively) (p < 0.02). Kaplan-Meier survival analysis showed better survival in shunt group 1 (seven patients thus far transplanted) than in either the liver transplant group or shunt group 2 during the early years and superior survival of shunt group 1 and the liver transplant group as compared to shunt group 2 during the later years of the analysis. Only two patients from shunt group 1 have died of late postoperative hepatic failure without benefit of liver transplantation., Conclusions: A shunt may serve as an excellent long-term bridge to liver transplantation in patients with well-preserved hepatic reserve. Shunt surgery still plays an important role in treatment of selected patients with variceal bleeding who are not present or future transplant candidates.

Objective: To evaluate the results of selective and nonselective emergency portosystemic shunts in patients with acute variceal hemorrhage., Design: Retrospective review., Setting: University medical center and Veterans Affairs medical center., Patients: Forty-two consecutive patients who underwent emergency portosystemic shunts from 1978 through 1994. All patients had chronic liver disease (29 [69%] had alcoholic cirrhosis) and half had Child's class C disease. Sixteen patients were actively bleeding at the time of surgery, and 26 had bled within 48 hours. Twenty-two patients underwent a nonselective shunt and 20 underwent a distal splenorenal shunt. The percentages of patients with Child's class C disease and with active bleeding at the time of surgery were significantly higher in the nonselective shunt group., Main Outcome Measures: Operative mortality; early postoperative rebleeding, shunt patency, encephalopathy, and ascites; and long-term survival., Results: Operative mortality rates were higher in patients with Child's class C disease (43% [9/21]) than in patients with Child's class A or B disease (9% [2/21]) and were higher in patients with active bleeding (all of whom underwent nonselective shunt) (44% [7/16]) than in patients who underwent distal splenorenal shunt (10% [2/20]). All shunts were patent after surgery, and no patient had rebleeding during the early postoperative interval. Early postoperative ascites and encephalopathy rates were similar after nonselective shunt and distal splenorenal shunt. Long-term survival was superior in the lower-risk distal splenorenal shunt group., Conclusions: Even though more effective nonoperative treatments are now available, emergency portosystemic shunt remains an important option for selected patients with acute variceal hemorrhage. When bleeding can be temporarily controlled by nonoperative means, distal splenorenal shunt is an effective and safe emergency procedure. The mortality rate remains high for patients with Child's class C disease undergoing protal decompression.

We studied the relative contributions of splanchnic congestion and porta-systemic shunting to the maintenance of experimental portal venous hypertension. Three groups of rats were prepared: portal vein-stenosed, superior mesenteric vein-ligated and sham operated. Though elevated in both operated groups compared to controls, mesenteric venous pressure was highest in the portal vein-stenosed animals (PV vs SMV vs Sham: 19.6 +/- 1.3 vs 15.6 +/- 0.7 vs 13 +/- 0.6; p < .05 PV and SMV vs Sham, and PV vs SMV) despite the presence of 50% porta-systemic shunting in the portal vein-stenosed animals. Shunting was negligible in the other two groups. Peripheral plasma glucagon and vasoactive intestinal peptide (VIP) levels were similar in all three groups. We conclude that mesenteric congestion alone plays a minor role in the pathogenesis of portal hypertension, which may instead be related to the porta-systemic shunting of vasoactive substances other than glucagon and VIP.

The advent of more effective nonoperative therapies, mainly endoscopic variceal sclerosis, has decreased the need for emergency surgery for control of acute variceal hemorrhage. In centers where it is available, nonoperative portal decompression by transjugular intrahepatic portosystemic shunting (TIPS) is likely to have a further impact. When acute or chronic sclerotherapy fails or when bleeding is secondary to gastric varices or portal hypertensive gastropathy, emergency surgery may be life-saving and should be done promptly before worsening hepatic functional decompensation develops. Child's class C liver disease is not a contraindication to emergency surgery; many patients who fail nonoperative attempts at control of bleeding are of this risk status. The most commonly utilized emergency procedures are portacaval and interposition mesocaval shunts, both of which are effective, and esophageal transection, which is associated with a higher incidence of late rebleeding. An emergency distal splenorenal shunt is appropriate for selected patients who are not actively bleeding at the time of surgery. TIPS is the preferred alternative for acute or chronic endoscopic sclerotherapy failures who are candidates for liver transplantation within the succeeding 6 to 12 months.

No single shunt operation is ideal for all patients or all circumstances. The selective distal splenorenal shunt is preferred for the majority of patients, because it has the potential to preserve hepatic portal perfusion. Most evidence suggests that the distal splenorenal shunt is followed by a lower frequency of encephalopathy than is any type of nonselective shunt. Although theoretically attractive, the small-diameter interposition portacaval shunt has not yet been subjected to the scrutiny of controlled trials.

None of the portasystemic shunts are ideal for all patients with recurrent variceal hemorrhage. Hemodynamic and clinical status should determine the type of shunt selected. Patients with a compatible anatomy, hepatopetal protal flow and controlled ascites are best served by a distal splenorenal shunt. Patients with variceal hemorrhage and medically resistant ascites are candidates for a side-to-side shunt, with consideration being given to an operation that avoids dissection of the porta hepatis. The end-to-side portacaval shunt should be used only in the emergency situation when other options are not available. However, due to the effectiveness of other therapies, such as sclerotherapy, in controlling bleeding, emergency shunts are rarely required. On the basis of the controlled trials of distal splenorenal shunt versus sclerotherapy, the latter is the initial treatment of choice with distal splenorenal shunt used promptly when sclerotherapy fails. Patients who live in remote areas, and noncompliant individuals may be best served with a distal splenorenal shunt as initial therapy.

Definitive therapy for variceal hemorrhage has evolved during the past half century. Only completely decompressing shunts (nonselective shunts) were available before 1967. Additional options now include selective shunts, devascularization procedures, endoscopic sclerotherapy, pharmacotherapy, and hepatic transplantation. Although drug treatment is experimental at the present time, the remaining therapeutic options are applicable to various subgroups of patients and in certain clinical settings. At the University of Nebraska, patients with variceal bleeding are first grouped based on their candidacy for transplantation. Transplantation candidates with advanced (Child's class C) or symptomatic liver disease undergo transplantation as soon as possible. Future transplantation candidates with stable, asymptomatic liver disease undergo either long-term sclerotherapy or a distal splenorenal shunt if sclerotherapy fails or if they have poor access to tertiary medical care. These patients are carefully monitored so that they can undergo transplantation before they become high-operative risks. Patients who are not candidates for transplantation receive chronic variceal sclerotherapy as initial therapy so long as shunt surgery is readily available if sclerotherapy fails. When surgery is indicated, the distal splenorenal shunt is preferred to nonselective shunts because several controlled and uncontrolled series have demonstrated a lower frequency of encephalopathy after selective variceal decompression.

Although total diversion of portal blood flow has been considered to be the main factor leading to encephalopathy following nonselective shunt (NSS), increased intestinal absorption of cerebral toxins secondary to mesenteric venous decompression could also play a role. Conversely, the low frequency of encephalopathy after the distal splenorenal shunt (DSRS) may be due to preservation of both hepatic portal perfusion and mesenteric venous hypertension. Portal hemodynamics, intestinal absorption of D-xylose, ammonia metabolism, and clinical encephalopathy were assessed preoperatively and in the early and late postoperative periods in cirrhotic patients selected for the DSRS (n = 12) and NSS (n = 10). Preoperatively, NSS patients had significantly less hepatopetal portal blood flow (P = 0.03) and lower D-xylose absorption (P = 0.004) than DSRS patients. DSRS resulted in no significant alterations in hepatic portal perfusion, portal pressure, D-xylose absorption, fasting blood ammonia (NH3), or tolerance to an oral dose of ammonium chloride. In contrast, NSS resulted in complete portal diversion and decompression and significant enhancement of D-xylose absorption on both the early (P = 0.02) and late (P = 0.03) postoperative evaluations. Early and late postoperative levels of MH3 were significantly higher in NSS patients. Encephalopathy was more frequent after NSS (80%) than after DSRS (17%, P = 0.003). When all patients were considered, preoperative to early DSRS (17%, P = 0.003). When all patients were considered, preoperative to early postoperative change in NH3 correlated with change in D-xylose absorption (r = 0.52, p = 0.02), and there were significantly more individuals with a greater than 2 gm increase in D-xylose absorption who developed encephalopathy (83%) than patients with no or minimal increase in D-xylose absorption (33%, P = 0.04). The results of this study suggest that altered intestinal absorption may be one of many factors determining postshunt cerebral function.

We recently developed a radiocolloid technique for quantifying the fraction of superior mesenteric venous blood that bypasses liver sinusoids through extra- and intrahepatic collateral vessels. In the present investigation we applied this method, which is performed in conjunction with visceral angiography, to the assessment of patients with portal hypertension before and after surgical construction of portasystemic shunts. The mean corrected shunt index was 0.89 in 27 preoperative patients, and 48 percent of the patients had no evidence of sinusoidal perfusion by superior mesenteric venous blood (shunt index greater than 0.95). Sinusoidal perfusion was absent in five patients with residual hepatic portal flow by angiography, indicating that they had a high degree of intrahepatic shunting. Hepatic portal perfusion was preserved in 80 percent of patients after distal splenorenal shunt, and the corrected shunt index was significantly smaller after this procedure than after portacaval and interposition shunts. . Three patients with no sinusoidal perfusion by superior mesenteric blood preoperatively had restoration of portal flow after distal splenorenal shunt. Five patients undergoing portacaval and interposition shunts had no evidence of portal sinusoidal perfusion by the radiocolloid technique either before or after the operative procedure.

To assess the incidence, pathogenesis, and associated morbidity and mortality of hyperbilirubinemia following the distal splenorenal shunt, hepatic hemodynamics, liver function, and clinical course were evaluated before and after this procedure in 78 cirrhotic patients. Individuals with a peak postoperative bilirubin level greater than 5 mg/dL had a higher preoperative bilirubin concentration, worse Child's score, longer hospital stay, and higher mortality than patients with a peak postoperative bilirubin level less than 5 mg/dL. Mean preoperative and postoperative hepatic portal perfusion and sinusoidal pressure were similar in both groups. When only patients with minimally elevated preoperative bilirubin levels (less than 2 mg/dL) were analyzed, 83% of individuals who developed postoperative hyperbilirubinemia (level, greater than 5 mg/dL) had a major alteration in hepatic hemodynamics as manifested by either complete portal vein thrombosis or a marked change in sinusoidal pressure (greater than 4 mm Hg). Although preoperative hepatic functional reserve is the major determinant of postoperative bilirubin concentration, alterations in hepatic hemodynamics secondary to the distal splenorenal shunt may also play a role.

Since 1978, the operation chosen for patients with variceal hemorrhage has been based on preoperative hemodynamic and clinical factors. One hundred sixteen consecutive patients were managed with the following operations: distal splenorenal shunt (75 patients), nonselective shunts (33 patients), and nonshunting operation (8 patients). Emergency surgery was required in 19 percent of patients. The selection criteria used resulted in the majority of high risk patients receiving nonselective shunts. This selective operative approach resulted in an overall operative mortality of 12 percent, a median survival of 3 years, and postoperative encephalopathy, ascites, and recurrent variceal hemorrhage in 20, 23, and 11 percent of patients, respectively. Operative mortality for the total group was closely related to Child's class. Whereas encephalopathy was most frequent after nonselective shunts, ascites was more common after the distal splenorenal shunt. Recurrent hemorrhage rarely occurred after a shunting procedure, but was a frequent complication of nonshunting operations. Neither the type of procedure selected nor the cause of liver disease influenced long-term survival.

In September 1982, a prospective randomized trial comparing shunt surgery and endoscopic sclerotherapy for the elective management of variceal hemorrhage in patients with cirrhosis was initiated. Twenty-seven patients have received shunts (distal splenorenal = 23, nonselective = 4) and 30 patients have had chronic sclerotherapy. Eighty-six per cent of patients had alcoholic cirrhosis and 33% were Child's class C. After a mean follow-up of 25 months, 19% of shunt and 57% of sclerotherapy patients have had rebleeding (p = 0.003). Kaplan-Meier survival analysis reveals similar 2-year survival rates for shunt (65%) and sclerotherapy (61%) groups. Only two of 10 sclerotherapy failures have been salvaged by surgery. Posttherapy quantitative hepatic function, frequency of encephalopathy, and cumulative medical costs were similar for both groups. Hepatic portal perfusion and portal pressure at 1 year were better maintained by sclerotherapy than by distal splenorenal shunt. In conclusion, endoscopic sclerotherapy and shunt surgery provide similar results with respect to survival, hepatic function, frequency of encephalopathy, and costs. Sclerotherapy is an acceptable, but not superior, alternative to shunt surgery for treatment of variceal hemorrhage.

Marked changes in preoperative to postoperative corrected sinusoidal pressures (CSP) occurred in 51 per cent of a series of 51 patients undergoing the distal splenorenal shunt. Twenty patients who had the highest incidence of partial portal vein thrombosis, (48%--Group I), showed minimal pre- to postoperative changes in CSP. Twelve patients (Group II) who increased their CSP to 4 mm Hg or greater had marked postoperative hyperbilirubinemia and decreased portal blood flow. Fourteen patients who decreased their CSP 4 mm Hg or more postoperatively also showed moderate portal blood flow decrease without significant changes in liver enzymes. Morbidity and mortality were not significantly different among the three groups. The significance of these hemodynamic changes is not known.

Patients with cirrhosis who had undergone the distal splenorenal shunt were grouped based on preoperative to early postoperative changes in hepatic portal perfusion and corrected sinusoidal pressure. Early and late postoperative morbidity and mortality rates were determined for each hemodynamic group. Morbidity was least when both hepatic portal perfusion and sinusoidal pressure were maintained near preoperative levels (Group 1). Survival for this group was significantly better than for patients who lost portal flow to the liver during the early postoperative interval (Group 4). Patients with absent hepatic portal perfusion had the worst survival and greatest morbidity. Intermediate results were achieved for the two groups of patients that had postoperative preservation of portal perfusion but significant preoperative to postoperative alterations in sinusoidal pressure. Although survival curves for these two groups were not significantly different from Group 1, morbidity was greater, especially for patients with an increase in sinusoidal pressure (Group 2).