Long-term loss of Warren's shunt selectivity. Angiographic demonstration

Visualization of two-dimensional transverse blood flow direction using optical coherence tomography angiography

SIGNIFICANCE

Evaluation of vessel patency and blood flow direction is important in various medical situations, including diagnosis and monitoring of ischemic diseases, and image-guided vascular surgeries. While optical coherence tomography angiography (OCTA) is the most widely used functional extension of optical coherence tomography that visualizes three-dimensional vasculature, inability to provide information of blood flow direction is one of its limitations.

AIM

We demonstrate two-dimensional (2D) transverse blood flow direction imaging in en face OCTA.

APPROACH

A series of triangular beam scans for the fast axis was implemented in the horizontal direction for the first volume scan and in the vertical direction for the following volume scan, and the inter A-line OCTA was performed for the blood flow direction imaging while the stepwise pattern was used for each slow axis scan. The decorrelation differences between the forward and the backward inter A-line OCTA were calculated for the horizontal and the vertical fast axis scans, and the ratio of the horizontal and the vertical decorrelation differences was utilized to show the 2D transverse flow direction information.

RESULTS

OCTA flow direction imaging was verified using flow phantoms with various flow orientations and speeds, and we identified the flow speed range relative to the scan speed for reliable flow direction measurement. We demonstrated the visualization of 2D transverse blood flow orientations in mouse brain vascular networks in vivo.

CONCLUSIONS

The proposed OCTA imaging technique that provides information of 2D transverse flow direction can be utilized in various clinical applications and preclinical studies.

Nonendoscopic management strategies for acute esophagogastric variceal bleeding

Acute variceal bleeding is a potentially life-threatening complication of portal hypertension. Management consists of emergent hemostasis, therapy directed at hemodynamic resuscitation, protection of the airway, and prevention and treatment of complications including prophylactic use of antibiotics. Endoscopic treatment remains the mainstay in the management of acute variceal bleeding in combination with pharmacotherapy aimed at reducing portal pressure. This article intends to highlight only the current nonendoscopic treatment approaches for control of acute variceal bleeding.

[Portosystemic shunt surgery between TIPS and liver transplantation]

Portosystemic shunt surgery in addition to transjugular intrahepatic portosystemic shunt (TIPS) insertion must still be regarded as a current treatment option for portomesenteric decompression in patients with pharmacological and endoscopic treatment failure, where liver transplantation is not imminent. This applies to secondary prophylaxis of rebleeding from varices in patients with well preserved liver function, e.g. liver cirrhosis CHILD A or extrahepatic portal vein thrombosis. Even if emergency endoscopy represents the treatment of choice in the acute bleeding situation, latest data from San Diego on emergency portacaval shunt surgery are encouraging. Likewise, portacaval shunt procedures can be an attractive alternative to TIPS or liver transplantation for acute Budd-Chiari syndrome or veno-occlusive disease.This article is an update on the systematics and methodology of portacaval shunt surgery, emphasizing the significance of this treatment option based on latest studies.

Refractory acute variceal bleeding: what to do next?

Current recommendations for the treatment of acute variceal bleeding (AVB) are to combine hemodynamic stabilization, antibiotic prophylaxis, pharmacologic agents, and endoscopic treatment. However, despite the application of the current gold-standard pharmacologic and endoscopic treatment, failure to control bleeding or early rebleed within 5 days still occurs in 15% to 20% of patients with AVB. In case of treatment failure of the acute bleeding episode, if bleeding is mild and the patient is hemodynamically stable, a second endoscopic therapy may be attempted. If this fails, or if bleeding is severe, it is usually controlled temporarily with balloon tamponade until a definitive derivative treatment is applied. Transjugular intrahepatic portosystemic shunt is highly effective in this situation; however, despite the control of bleeding, a high proportion of these patients die of liver and multiorgan failure. Strategies intended to improve the prognosis of these patients should focus on identifying those high-risk patients in whom standard therapy is likely to fail, and who are therefore candidates for more aggressive therapies early after the development of AVB.

New trends in surgical treatment for portal hypertension

A number of surgical procedures have been developed to manage esophageal varices. Broadly, these can be classified as shunting and non-shunting procedures. While total shunt effectively reduces the incidence of variceal bleeding, it is associated with a high risk of hepatic encephalopathy. The distal splenorenal shunt (DSRS), a selective shunt, was developed by Warren in 1967 to preserve portal blood flow through the liver while lowering variceal pressure. The hope was that both bleeding and hyperammonemia would be prevented. The DSRS effectively prevents rebleeding, but still carries a risk of hyperammonemia. We improved the DSRS procedure by additionally performing splenopancreatic disconnection (SPD, i.e. skeletonization of the splenic vein from the pancreas to its bifurcation at the splenic hilum) and gastric transection (GT, i.e. transection and anastomosis of the upper stomach with an autosuture instrument). An alternative to shunting was developed by Sugiura and Futagawa in 1973. Esophageal transection (ET) divides and reanastomoses the distal esophagus and devascularizes the distal esophagus and proximal stomach; splenectomy, selective vagotomy, and pyloroplasty are performed concomitantly. DSRS was more effective than ET in preventing recurrence of esophageal varices, but was associated with a higher incidence of hyperammonemia. The incidence of hyperammonemia in patients who underwent DSRS with SPD plus GT was significantly lower than that in patients who underwent DSRS alone or those who underwent DSRS with SPD. In conclusion, there are various surgical treatments for esophagogastric varices. Distal splenorenal shunt with SPD plus GT is considered an adequate treatment for patients with esophagogastric varices.

Triple-phase computed tomography and intraoperative flow measurements improve the management of portosystemic shunts during liver transplantation

Ligation of portosystemic shunts in patients with cirrhosis undergoing liver transplantation has been recommended to avoid insufficient portal vein (PV) flow. Shunts are not always recognized pretransplantation because intraoperative PV flow assessment is not routinely attempted. As a result of a posttransplantation PV thrombosis in a recipient with a large portosystemic shunt and a PV flow <1 L/minute, we employed triple-phase computed tomography with vascular reconstruction and intraoperative graft flow measurement to determine the need for inflow modification in our next 16 patients with large portosystemic shunts. Subsequently, 6 patients with large portosystemic shunts and PV flows <or=1 L/minute underwent inflow modification at the time of transplantation to improve venous graft inflow. One patient with PV thrombosis had PV replacement without shunt ligation. Two patients with large splenorenal shunts and extensive PV thrombosis had left renoportal bypass. In 7 patients with large portosystemic shunts and PV flow greater than 1 L/minute, inflow modification was not attempted, to avoid excessive venous inflow that could jeopardize hepatic artery flow via the hepatic artery buffer response. In conclusion, sustained good graft function and inflow were achieved in all 16 patients.

Portaprival collaterals following distal splenorenal shunt. Incidence, magnitude and associated portal perfusion changes

Collateral venous pathways develop between the high pressure portal vein and low pressure splenic vein following distal splenorenal shunt. This review of angiography in 50 patients with cirrhosis prior to and 1 year after DSRS shows that 98% developed collaterals: 72% transpancreatic, 48% transgastric, and 46% colonic. Multiple pathways developed in 64% of patients. Grading of the size of these collaterals showed that in 74% these exceeded the size of the portal and/or superior mesenteric vein. The effect of these collaterals on portal perfusion showed that 32% lost perfusion at 1 year, but significantly (P less than 0.05) more alcoholics (48%) lost perfusion than nonalcoholics (16%). The size, site and number of collaterals was not different between etiologies. Late follow-up in a subset of 32 of the patients showed no change in the site, and minimal increase in size of the collaterals at 3-11 years, with no further loss of portal perfusion. We conclude that virtually all patients develop collaterals after DSRS, these are along predictable pathways and are of significant size in the majority. However, development of collaterals per se does not equate to loss of portal venous flow, and a stable pattern is set in the first year after shunt. Characterization of these pathways will permit new approaches to minimizing their development.

Liver transplantation in patients with splenorenal shunts: intraoperative flow measurements to indicate shunt occlusion

Two patients with previous distal splenorenal shunts (DSRSs) performed 6 years earlier underwent liver transplantation (LT). A preoperative selective mesenteric artery angiogram showed collateral veins draining mesenteric venous flow into the shunt. Intraoperative flow measurements were performed to assess the steal of portal venous flow by the shunt and determine the need for shunt occlusion. Portal vein, hepatic artery, and shunt flows were measured by ultrasound transit-time flow probes in the native liver and after graft implantation with and without temporary shunt occlusion. Hemodynamic studies showed that long-standing DSRSs are high-flow shunts that steal portal flow. After graft implantation, DSRS flows remained high. Occlusion of the shunts produced an increase in portal vein flow at an amount similar to those of splenorenal shunt. Thus, the flow measurements showed persistent steal by the shunts after graft implantation and, therefore, the DSRSs were occluded but splenectomy was not performed. We conclude that the decision to occlude a DSRS should be based on the demonstration of steal of portal flow by the shunt and reversibility once the shunt is occluded. Splenectomy is not required when the DSRS is occluded.

Afluência da veia esplênica e sua importância nas derivações esplenorrenais seletivas

Os autores realizaram estudo da afluência da veia esplênica utilizando 38 moldes de duodeno, estômago, pâncreas e baço, por meio da técnica de repleção e corrosão, com vinilite corado com azul da Prússia. Os afluentes encontrados foram: ramos pancreáticos em todas as peças, variando de 7 a 22 ramos, com média de 14,52 ± 3,53; a veia gástrica esquerda, em 36,84% das peças; a veia mesentérica inferior em 44,74% das peças; ramo gástrico (gástrica posterior), proveniente do fundo gástrico, em 57,89% das peças, e ramos pancreáticos, provenientes da cauda do pâncreas e desembocando em ramos segmentares da veia esplênica, em 65,79% das peças. Os ramos pancreáticos variaram em número de um a quatro, com média de 1,64 ± 0,95. Os autores concluem que o conhecimento dos afluentes da veia esplênica seria importante na realização das derivações esplenorrenais distais, quando associadas à desconexão esplenopancreática.

An evaluation of splenopancreatic disconnection as a modification of the distal splenorenal shunt, studied in nonalcoholic patients by sequential angiography

To evaluate the validity and complications of modifying the distal splenorenal shunt (DSRS) by performing splenopancreatic disconnection (SPD), hemodynamic changes in the portal system were assessed by visceral angiography in 93 patients with nonalcoholic portal hypertension during early postoperative follow-up after DSRS. There were 40 patients who underwent DSRS alone and 53 who underwent DSRS plus SPD. Early follow-up angiography showed that portal vein perfusion was well maintained, and that the diameter of the portal vein had decreased significantly by the same degree in both groups. Hepatofugal collaterals for the shunt had developed to a greater extent in the DSRS group, while they were almost completely absent in the DSRS with SPD group. Nevertheless, partial portal vein thrombosis was not detected in the DSRS group, although it was seen in seven (13.2%) of the patients who underwent DSRS plus SPD, in whom the left proximal splenic vein was not visible. The proximal splenic vein was seen in significantly less of the DSRS with SPD patients (47.2%) than the DSRS group patients (85%). In conclusion, SPD more effectively prevented the early postoperative development of collateral pathways for the shunt compared with standard DSRS; however, the possible stagnation of blood flow in the left proximal splenic vein may predispose to a risk of partial portal vein thrombosis developing during the early postoperative period after DSRS with SPD.

The effect of splenomegaly on splanchnic hemodynamics in nonalcoholic cirrhosis after distal splenorenal shunt and splenopancreatic disconnection

We investigated the effect of splenomegaly on portal hemodynamics during and after distal splenorenal shunt with splenopancreatic disconnection in 27 patients with nonalcoholic cirrhosis (13 with and 14 without splenic enlargement). Data were obtained by Doppler flowmetry, electromagnetic flowmetry and computed tomographical scanning. The splenomegaly group had a significantly higher preoperative splenic and portal blood flow than the nonsplenomegaly group. In both groups, postoperative portal venous pressure did not fall; portal blood flow significantly decreased while splenic volume was reduced, despite the lack of significant changes in splenic venous blood flow. There was a greater reduction of portal blood flow with previous splenomegaly than with normal-sized spleens, and this was not related to the degree of reduction in liver volume. In the splenomegaly group, the increase of splenic blood flow was only present during the early postoperative period. In conclusion, distal splenorenal shunt with splenopancreatic disconnection influenced portal hemodynamics differently in nonalcoholic cirrhotic patients with and without splenomegaly.

Treatment of portal hypertension in children

The management of children with portal hypertension (PH) has substantially changed owing to the good results and broader application of both endoscopic sclerotherapy and orthotopic liver transplantation (OLT). Since the introduction of sclerotherapy for the treatment of bleeding esophageal varices, the number of surgical procedures has sharply decreased. Until the early 1980s, however, the treatment of choice of bleeding esophageal varices was based on different variations of two main types of open surgery: devacularization and transection operations and portosystemic shunts. The experience with nonshunt procedures is limited in the pediatric population. Literature reports from the last 25 years have emphasized a number of restrictions related to portosystemic shunts in small subjects. However, portosystemic shunts, selective or not, can be performed even in very young subjects with high rates of success. From 1974 to 1984 the distal splenorenal shunt (DSRS) was the procedure of choice for the treatment of children with variceal bleeding in our institution. Forty-two children underwent DSRS during this period. Since 1985, when endoscopic variceal sclerotherapy (EVS) replaced DSRS as the first therapeutic option in our service, this shunt has been performed in only 8 children in whom EVS has failed, none of them during the last 2 years. In this cohort of 50 cases of DSRS, the shunt patency has increased from 71% in the first 7 patients to 95% thereafter. There has been no perioperative mortality. From 1985 to April 1993, 107 children were submitted to EVS sessions for the treatment of esophageal varices bleeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Total shunting and elective management of variceal bleeding

A 20-year experience with treatment of esophageal varices in patients with cirrhosis is reported. Considering that total shunts are well tolerated immediately after operation (hospital mortality rate for all elective procedures being 6.4%), that they offer a good protection against rebleeding (rebleeding variceal rate of 7.6%), and that they offer the same long-term survival as given by other shunts (5- and 10-year survival rates of 57% and 31%, respectively), the authors affirm that these kinds of shunts are still useful in well selected cases. Late follow-up results of a prospective randomized trial of elective mesocaval shunts compared to portacaval shunt have shown no significant differences in operative mortality, rebleeding rates, encephalopathy rates, or survival. Based on this information, the authors currently use portacaval shunt as their operation of choice.

Portal hypertension and bleeding esophageal varices

Bleeding from esophageal varices exacts a high mortality and extraordinary societal costs. Prophylaxis--medication, sclerotherapy, or shunt surgery to prevent an initial bleeding episode--is ineffective. In patients who have bled from varices, endoscopic injection sclerotherapy can control acute bleeding in more than 90% of patients. Because recurrent bleeding frequently occurs and survival without definitive therapy is dismal, selection of a permanently effective treatment is mandatory once variceal bleeding has been controlled. Long-term injection sclerotherapy can be performed in compliant patients; it is relatively safe but is associated with a 30-50% rebleeding rate. Beta-blockers significantly reduce portal pressure and recurrent bleeding but have not been shown to diminish mortality from BEV. Portal decompressive surgery permanently halts bleeding in more than 90% of patients; the risk of operative mortality is high in decompensated cirrhotics, and long-term complications of encephalopathy and accelerated liver failure may limit indications for shunt surgery to good-risk cirrhotics who are not liver transplant candidates. Devascularization procedures have a low operative mortality and encephalopathy rate but unacceptably high rates of recurrent bleeding. Liver transplantation is curative therapy for bleeding esophageal varices and the associated underlying hepatic dysfunction; cost and availability of donor organs generally limit its use in this setting to variceal bleeders with end-stage liver disease not associated with active alcoholism.

Long-term effects of distal splenorenal shunt on hepatic hemodynamics and liver function in patients with cirrhosis: importance of reversal of portal blood flow

We studied 23 patients with cirrhosis who had undergone retroperitoneal distal splenorenal shunt without portal-azygos disconnection more than 2 yr earlier. We investigated the suitability of the Doppler technique (ultrasound + Doppler) to assess the patency and blood flow direction through the portal vein and the distal splenorenal shunt and its correlation with the continuous thermal dilution technique. The study also assessed the influence of the distal splenorenal shunt and time after surgery on portal perfusion and liver function. Ultrasound + Doppler distal splenorenal shunt thrombosis in two patients; however, none was confirmed by continuous thermal dilution. Ultrasound + Doppler flowmetry was possible in 19 patients (83%) (mean, 1.58 +/- 0.53 L/min). Distal splenorenal shunt continuous thermal dilution measurements were performed in all patients (100%), (mean, 1.65 +/- 0.5 L/min). Good correlation was seen between them (r = 0.66). Ultrasound + Doppler of the portal vein showed a hepatopetal flow in 16 patients (69.9%). Hepatic blood flow was significantly higher in patients with hepatopetal flow (p = 0.003). Hepatic clearance and intrinsic hepatic clearance of indocyanine green were significantly lower in patients with hepatofugal flow. Patients with hepatofugal flow had a higher incidence of chronic encephalopathy. None of the patients with a follow-up of less than 4 yr exhibited hepatofugal flow, whereas 7 of the 16 patients with a longer follow-up had hepatofugal flow (43.7%). The difference was statistically significant (p = 0.04). This study suggests that ultrasound + Doppler sonography may provide useful data in the evaluation of the patency and blood flow direction through the portal vein and the distal splenorenal shunt.(ABSTRACT TRUNCATED AT 250 WORDS)

Should both schistosomal and nonschistosomal variceal bleeders be disconnected?

Splenopancreatic disconnection (SPD) was conceived and implemented as a technical addition to distal splenorenal shunt (DSRS) to maintain its selectivity and preserve portal perfusion. The proposed hemodynamic and metabolic stability of hepatocytes after DSRS-SPD should improve survival. In this nonrandomized study, 145 consecutive (Child A/B) variceal bleeders were electively subjected to selective shunt with DSRS in 93 and DSRS-SPD in 52 patients. The 2 groups were similar before surgery with a mean follow up of 24 +/- 12 (DSRS) and 27 +/- 14 (DSRS-SPD) months. DSRS-SPD had an operative mortality of 3.8%. Postoperative pancreatitis occurred in 7.7% after DSRS-SPD and 3.2% after DSRS alone, with schistosomal hepatic fibrosis representing 86% of morbid cases. Shunt patency was high and recurrent variceal hemorrhage was low in both groups. Clinical encephalopathy was significantly reduced after DSRS-SPD (p less than 0.05). The addition of SPD significantly reduced both the incidence of chronic hyperbilirubinemia in the schistosomal patients (p less than 0.05) and the difference between the changes in total serum bilirubin in all patients (p = 0.001). Portal perfusion was preserved after DSRS-SPD in all of the angiographically-studied patients. The overall survival was 84% after DSRS and 88% after DSRS-SPD. The schistosomal patients showed an incidence of 95% and 96% survival after DSRS and DSRS-SPD, respectively. DSRS-SPD was able to improve survival (92%) better than DSRS (77%) among well-matched nonschistosomal patients. These data show: (1) DSRS-SPD still has low operative mortality and a high patency rate with a low incidence of recurrent variceal hemorrhage, (2) DSRS-SPD maintains portal perfusion, achieves better survival, and reduces the incidence of encephalopathy, especially in patients with nonalcoholic cirrhosis and mixed liver disease, (3) in the schistosomal population, DSRS-SPD reduces the incidence of chronic hyperbilirubinemia but increases the risk of postoperative pancreatitis.

The endoscopic and surgical management of portal hypertension in children: analysis of 123 cases

Since 1973, 178 children with portal hypertension (PH) have been seen at Instituto da Criança of the University of São Paulo Medical School. Fifty-five of these children were excluded from this analysis for various reasons, including no treatment required, death before treatment, or incomplete data. From the remaining 123 children with esophageal varices, only 96 (76.1%) of them had at least one episode of upper gastrointestinal hemorrhage. Eighty-eight children were submitted to injection sclerotherapy; 26 treated prophylactically, and 62 for treatment of previous bleeding. Eleven (42.3%) children from the prophylactic group bled from esophageal varices during the treatment. They were all successfully managed thereafter. Satisfactory results were achieved in 53 (85.4%) children in the therapeutic group. Twenty-eight (45.1%) children had at least one episode of bleeding after beginning of sclerotherapy, 19 of whom eventually had successful control of the variceal bleeding. From 1973 to 1984, distal splenorenal shunt (DSS) was the procedure of choice for the treatment of bleeding esophageal varices. Forty-two children have undergone DSS during this period. Only one child was shunted prophylactically. Since 1985, injection sclerotherapy has been the first choice for the treatment and only seven children with sclerotherapy failure have since been treated by DSS. Characteristically these children had very similar splenoportographic pattern with huge esophageal and gastric varices and deviation of portal vein blood flow toward the left gastric vein.(ABSTRACT TRUNCATED AT 250 WORDS)

Selective shunt versus nonshunt surgery for management of both schistosomal and nonschistosomal variceal bleeders

This clinical study included 219 (Child A/B) consecutive variceal bleeders. Electively 123 had distal splenorenal shunt (DSRS) and 96 had splenectomy with gastroesophageal devascularization (S&GD). Liver pathology was documented in 73% of patients, with schistosomal fibrosis in 41% and nonalcoholic cirrhosis or mixed pattern (fibrosis and cirrhosis) in 59%. The surgical groups were similar before operation, with a mean follow-up of 82 +/- 13 and 78 +/- 18 months, respectively (range, 60 to 120 months). The two pathologic populations were also similar before each and both procedures. The operative mortality rates were low, with incidences of 3.3% (DSRS) and 3.1% (S&GD). Rebleeding occurred significantly (p less than 0.05) more frequently after S&GD (27%) compared to DSRS (5.7%). Sclerotherapy salvaged 65% of S&GD rebleeders. Encephalopathy developed significantly (p less than 0.05) more after DSRS (18.7%) compared to S&GD (7.3%), with no significant difference among the current survivors. The difference in overall rebleeding and encephalopathy rates between both procedures was statistically related to patients with cirrhosis and mixed lesions (p less than 0.05). Distal splenorenal shunt significantly reduced the endoscopic variceal size more than S&GD (p less than 0.05). Prograde portal perfusion was documented in 94% of patients in each group, with a variable distinct pattern of portaprival collaterals in 91% (DSRS) and 65% (S&GD). The total population cumulative survival was similar with 80% for DSRS and 79% for S&GD (plus sclerosis in 23%), with hepatic cell failure the cause of death in 46% and 50%, respectively. However, in the schistosomal patients, survival was better improved after DSRS (90%) compared to S&GD (75%), with no difference among the cirrhotic and mixed group (DSRS 73%, S&GD 72%). In conclusion (1) both DSRS and S&GD have low operative mortality rates, (2) DSRS is superior to S&GD in the schistosomal patients, and (3) S&GD backed by endosclerosis for rebleeding is a good surgical alternative to selective shunt in the nonalcoholic cirrhotic and mixed population.

The Emory perspective of the distal splenorenal shunt in 1990

The distal splenorenal shunt (DSRS) has been extensively studied at Emory University over the past 18 years to define its role in the management of variceal bleeding. DSRS has been applied broadly in many different patient groups and has been evaluated in prospective randomized trials; thus, a considerable amount of data has accrued on the metabolic and hemodynamic consequences of selective variceal decompression. Its current role is defined as primary therapy for variceal bleeding in patients with portal vein thrombosis and good-risk patients with nonalcoholic cirrhosis. As a therapy for patients whose bleeding is not controlled by sclerotherapy, it should be used as the shunt procedure of choice, but patient evaluation must focus on the choice between DSRS and liver transplantation.

Selective shunts: the Johannesburg experience

My personal 15-year experience with 141 selective shunts (127 elective, 14 emergency) for portal hypertension is reported. Alcoholic cirrhosis comprised 54% of elective operations, and of the nonalcoholic patients, 22% were cirrhotic and 24% were noncirrhotic. Adequate and, if necessary, prolonged (mean 6 weeks) in-hospital preparation resulted in Hospital mortality and long-term actuarial survival were better in nonalcoholics compared with alcoholics, but there was no significant difference between cirrhotic nonalcoholics and alcoholics. Variceal rebleeding was rare (4% of Warren procedures) and, when present, was usually related to shunt failure. Gastric fundal variceal rebleeding did not occur in 44 patients undergoing splenopancreatic disconnection. Postoperative encephalopathy occurred in 13% of patients; however, it did not occur at all in noncirrhotic patients. Prograde portal venous perfusion was preserved in 77% of patients. Fifteen alternate selective operations to the Warren shunt were performed, usually because of antecedent splenectomy. Shunt failure and variceal rebleeding occurred more frequently with these more vulnerable shunts, but 66% had a satisfactory outcome. Selective shunts have produced highly satisfactory results in appropriately selected patients.

Treatment of variceal hemorrhage in children

The etiology and management of portal hypertension in infants and children differ from those in adults. Both the plan of management and the prognosis of portal hypertension vary considerably depending upon the nature of the underlying pathologic process. It is essential to determine the type of obstruction as accurately as possible before definitive treatment is initiated. This article considers the management of extrahepatic, intrahepatic, and suprahepatic portal venous obstruction; treatment of the unshuntable patient; portosystemic shunts; and liver transplantation.

The distal splenorenal shunt

Distal splenorenal shunt (DSRS) provides selective decompression of gastroesophageal varices, with maintenance of portal hypertension and prograde portal flow to the cirrhotic liver. Accurate patient evaluation is essential to select appropriate patients for DSRS. Variceal bleeding control is greater than 85% and is as effective as total portosystemic shunts. Maintenance of prograde portal flow is greater than 90% in nonalcoholic disease, but only 50% in alcoholic cirrhosis; the latter is improved by total splenopancreatic disconnection. Hepatic function is better maintained when portal flow is maintained. Encephalopathy is lower after DSRS than after total shunts. Survival is not significantly improved after DSRS in patients with alcoholic cirrhosis compared to outcome after total shunts. The survival in patients with nonalcoholic disease is significantly improved over that of alcoholics.

Duplex ultrasonography of the portal vein

Although the ability of ultrasonography to provide anatomic detail and physiologic information about the arterial system is well established, its applicability for the venous system and the splanchnic circulation has only recently been recognized. We have found duplex scanning, which is non-invasive, rapid, inexpensive, and reproducible, to be highly accurate in (1) establishing or confirming the diagnosis of portal hypertension, (2) demonstrating portal and splenic vein patency and direction of flow, (3) assessing portosystemic shunt patency, and (4) providing novel anatomic and physiologic information regarding the normal and diseased splanchnic venous system. These ultrasonographic techniques also have a significant role to play in the surveillance of patients who have undergone liver transplantation or massive liver resection. To a great extent, ultrasonography may supplant the invasiveness, discomfort, and expense of contrast angiography in the evaluation of many patients with advanced liver disease.

Early hemodynamic changes following selective distal splenorenal shunt for portal hypertension: comparison of surgical techniques

Ninety patients with cirrhosis undergoing elective distal splenorenal shunt (DSRS) for variceal bleeding between January, 1977 and September, 1988 comprised the study group. In 63 cases, the original technique of Warren was used and, in 15, the modified Britton procedure was employed. Twelve patients had a DSRS plus splenopancreatic disconnection. Thirty-four had alcoholic cirrhosis and 56 had nonalcoholic cirrhosis. Intraoperative portal pressure remained high after the shunt (29.4 cm H2O) even if its initial value was probably decreased by the loss of the splenic flow. Splenic pressure was reduced to 21 cm H2O. The hepatic artery diameter enlarged even after selective shunt (from 6.5 to 7.1 mm). The persistence of a high portal pressure allowed for the preservation of hepatopedal portal flow in 87% of cases. Disconnection between the high-pressure mesenteric area and the low-pressure splenic area seemed to be ideal in only 17% of cases. Fifty-five percent of cases had the early development of minimal or moderate portomesenteric gastrosplenic (PM-GS) collateral pathways. In 33%, the PM-GS collaterals were generally abundant and often allowed visualization of the splenic and caval veins during the venous phase of the superior mesenteric arteriograms. In this group, portal flow was generally highly reduced and even abolished. The incidence of portal thrombosis was 11%. Early angiographic checks after DSRS did not show a different hemodynamic behavior between alcoholics and nonalcoholics. Splenopancreatic disconnection seems to prevent the development of collaterals and the loss of portal perfusion after shunt surgery.

Development of chronic hepatocerebral degeneration eight years after a distal splenorenal (Warren) shunt

It is well known that chronic encephalopathy may be a major complication after the establishment of a surgical portal caval shunt for an episode of variceal haemorrhage. In an effort to minimise this problem Warren and colleagues developed the distal splenorenal shunt where the portal and mesenteric blood flow to the liver was left intact. It is now recognised, however, that the longterm incidence of encephalopathy may be no different with this type of shunt compared with conventional surgical portal systemic shunts. Acquired chronic hepatocerebral degeneration has not been reported after such a selective shunt. A patient with primary biliary cirrhosis is reported who developed the clinical features of this syndrome eight years after a successful distal splenorenal shunt.

Distal splenorenal shunt with splenopancreatic disconnection. A 4-year assessment

The aims of distal splenorenal shunt with splenopancreatic disconnection (DSRS-SPD) were to improve maintenance of portal flow and prevent siphoning of hepatotrophic factors from the pancreas, as occurs after standard DSRS. The main patient population targeted for improvement were alcoholic cirrhotics, who have poorer survival than nonalcoholic cirrhotics and greater loss of portal flow (60%) after standard DSRS. Seventy-eight patients had DSRS-SPD during the study period 1983 to 1987: thirty-two patients were Child's A, 25 were Child's B, and 21 were Child's C. The 35 patients with alcoholic cirrhosis were a significantly poorer risk group by Child's class and galactose elimination capacity (GEC) than the 39 patients with nonalcoholic cirrhosis. Four patients had portal vein thrombosis. At 4-year follow-up, portal perfusion is maintained in 84% alcoholic and 90% nonalcoholic patients, with hepatic and systemic hemodynamics showing identical patterns for both groups. Hepatic function measured by GEC was maintained in alcoholic patients (290 +/- 68 mg/min to 303 +/- 74 mg/min) and nonalcoholics patients (342 +/- 92 to 320 +/- 118 mg/min). Gastric variceal rebleeding occurred in 10 patients--4 early (less than 2 months) and 6 late (18 to 54 months), leading to operation in 4 and transhepatic embolization in 4 patients: 2 of these patients died from this complication. Survival data show an operative mortality rate of 6.4% and overall mortality rate of 30%, with no significant difference between alcoholic and nonalcoholic cirrhotics. DSRS-SPD has significantly improved maintenance of portal perfusion and survival in patients with alcoholic cirrhosis requiring selective shunt for variceal bleeding when compared to standard DSRS. In this population DSRS-SPD is the operation of choice. In patients with nonalcoholic cirrhosis, the current data have not shown DSRS-SPD to have advantage over standard DSRS.

Schistosomal versus nonschistosomal variceal bleeders. Do they respond differently to selective shunt (DSRS)?

The distal splenorenal shunt (DSRS) was performed in 125 consecutive variceal bleeders. To date, no patients have been lost to follow-up (mean of 79 +/- 20 months). Liver pathology was documented in 85 patients: 45 patients had schistosomal hepatic fibrosis, 17 had nonalcoholic cirrhosis, and 23 had mixed pattern (hepatic fibrosis and cirrhosis). The preoperative data base for these three groups was matched (p greater than 0.05), with a mean follow-up of 79 +/- 20, 70 +/- 14, and 77 +/- 22 months for each population, respectively. The results showed low operative mortality (4.8%), high cumulative patency rate (94.8%) and low recurrent variceal hemorrhage (5.6%). The biochemical data showed significant increase in serum bilirubin (p less than 0.001) and aspartate transaminase (AST) (p less than 0.05) in the nonschistosomal patients. Chronic hyperbilirubinemia was found in 33% of the schistosomal group. Prograde portal perfusion was detected in 94% of the patients, with development of collaterals in 91%. The angiographic pattern of these collaterals was 50% pancreatic, 45% gastric, and 26% colosplenic. Patients with mixed liver disease had a high incidence of Grade III portal perfusion (57%) and more common pancreatic and gastric collaterals (71%). The cumulative survival for all patients was 74.1%, with hepatic cell failure being the leading cause of death (13 patients, 50% of all deaths). The schistosomal patients had a 91.6% incidence, whereas the cirrhotic and mixed groups had survival rates of 75.6% and 65.2%, respectively. Also, of a 15% total incidence of encephalopathy, 4.4% was related to the schistosomal patients, 23.5% to the cirrhotics, and 21.7% to the mixed population. Statistically, the survival rate was significantly better (p less than 0.05) and encephalopathy was significantly lower (p less than 0.05) in the schistosomal population. In conclusion, this data shows that: 1) DSRS has a high patency rate and a low variceal hemorrhage recurrence rate; 2) it maintains some degree of portal perfusion in patients with different nonalcoholic liver diseases, despite development of collaterals; and 3) the schistosomal patients have a better survival rate, with a low incidence of encephalopathy after DSRS, compared with the cirrhotic and mixed populations.

Selective distal splenorenal shunt versus side-to-side portacaval shunt. Clinical results of a prospective, controlled study

A prospective, controlled study comparing the clinical results of the selective distal splenorenal shunt procedure and the side-to-side portacaval shunt procedure was undertaken in 1980. Ninety-three cirrhotic patients with previous episodes of bleeding from esophageal varices underwent a distal splenorenal shunt procedure (47 patients). The operative mortality rate was 2 percent in both groups. The intraoperative decrease of portal hypertension after the portacaval shunt procedure was higher than after the distal splenorenal shunt procedure (p less than 0.05), and in those with patent shunts, there was a 0 percent incidence of early variceal rebleeding after the portacaval shunt procedure compared with a 9 percent incidence after the distal splenorenal shunt procedure (p less than 0.05). Both shunts, however, had similarly satisfactory results in preventing long-term variceal rebleeding (portacaval shunt 2 percent and distal splenorenal shunt 0 percent). Postoperative ascites was more common after the distal splenorenal shunt procedure (58 percent versus 24 percent; p less than 0.01). Analysis of actuarial survival curves showed no difference between the two procedures. The incidences of long-term episodes of chronic encephalopathy were not statistically different after both procedures. The only three instances of severe encephalopathy occurred in patients with the portacaval shunt (p less than 0.05). The distal splenorenal shunt also seemed to have a less negative effect on postoperative liver function than the portacaval shunt. These data suggest that the selective shunt should be viewed as a first choice strategy in the treatment of portal hypertension.

Influence of portal hemodynamics on long-term survival of alcoholic cirrhotic patients after small-diameter portacaval H grafts

Estimating postoperative survival rates after portasystemic shunt procedures has concerned surgeons during the last 40 years. The relationship between survival and Child's classification has clearly demonstrated the importance of preoperative hepatic functional reserve. Maintaining hepatic portal perfusion has been proposed as an additional protective factor but has never been proved clinically. Our analysis of survival after partial shunting with small-diameter portacaval H grafts has shown that both hepatic functional reserve and postoperative portal perfusion correlate with postoperative survival in alcoholic patients, but the latter was a stronger correlate of long-term survival. A predictive model based on both factors has been described for estimating the overall survival rate of alcoholics after partial shunting with small-diameter portacaval H grafts.

[Portal circulation following the Warren operation--computerized tomography study of portal hemodynamics 5 to 11 years following distal splenorenal anastomosis]

18 patients underwent CT-investigation with bolus injection of contrast medium 5 to 11 years after splenorenal Warren shunt. According to this investigation all patients were found to have developed hepatofugal collaterals in consequence of distal splenorenal anastomotic suction. In most cases the portal liver perfusion was maintained. These effects are not homogeneous and show variations from patient to patient.

The long-term effect of distal lienorenal shunt surgery on portal venous pressure

To assess whether portal venous pressure remains elevated following distal lienorenal shunt surgery, 11 patients with alcoholic cirrhosis were assessed from 0.5 to 59 months following the creation of a distal lienorenal shunt. These were compared with five patients following mesocaval shunt surgery and nine with cirrhosis alone. Portal pressure was measured by direct transhepatic catheterization of the portal vein or by determining intrahepatic pulp pressure. Splenic pulp pressure was also measured in the shunt groups at the time of assessment of shunt patency by scintisplenoportography. All shunts were patent. Four of five patients studied within 10 months of distal lienorenal shunt surgery had persisting portal hypertension (comparable with that in the cirrhosis alone group) and persisting portasplenic gradient. In contrast, five of six patients studied more than 10 months following surgery had portal pressures similar to that following mesocaval shunt surgery and no portasplenic gradient. Thus, with time, selective decompression tends to become total decompression. Whether this correlates with deterioration of hepatic function requires further study.

The Emory prospective randomized trial: selective versus nonselective shunt to control variceal bleeding. Ten year follow-up

From 1971 to 1975, 55 patients with variceal bleeding secondary to cirrhosis were entered into a prospective randomized trial comparing distal splenorenal (selective) and H-graft interposition (nonselective) shunt. This 10-year follow-up documents that selective shunt is better (p less than 0.05) in four of the five variables monitored. Control of bleeding: selective shunt prevented variceal bleeding better than interposition shunt due to the higher (0.05 less than p less than 0.1) occlusion rate (30%) of interposition shunt. Selective shunt maintained postoperative portal perfusion better (p less than 0.01) than patent interposition shunt. Seventy-five per cent of selective shunt survivors have portal perfusion at 10 years: no patient with a patent nonselective shunt perfuses the liver. Quantitative liver function was better preserved (p less than 0.01) 10 years after selective shunt than nonselective shunt. Postoperative encephalopathy occurred in fewer (p less than 0.01) selective (27%) than nonselective (75%) shunt patients over the 10 years. Survival: in the randomized population, the improved survival in the selective shunt subgroup did not reach statistical significance. However, improved survival was confirmed in nonalcoholics. Five of eight nonalcoholics operated with selective shunt are alive at 10 years with patent shunts. No nonalcoholic, of seven total, operated with nonselective shunt survived 10 years with a patent shunt. These data show that selective shunt was superior to nonselective shunt. There was less rebleeding and encephalopathy after distal splenorenal shunt; postoperative portal perfusion and hepatic function were maintained.

Exclusion of nonisolated splenic vein in distal splenorenal shunt for prevention of portal malcirculation

In an attempt to prevent portoprival malcirculation after distal splenorenal shunt (DSRS), a splenic hilar renal shunt (HRS) with proximal flush ligation of splenic vein was designed. To accomplish this procedure, two methods were compared: HRS alone (Group A) and HRS plus proximal flush ligation of the splenic vein (Group B). In Group A, which included 20 cirrhotic patients with esophageal varices, angiographic as well as pulsed Doppler flowmetric follow-up study revealed a portal thrombosis in two patients and severe narrowing of a portal vein in another two. Considerable stealing flow was observed in these four patients. In the Group B series, which included 33 cirrhotic patients, there were no gross changes in the portal hemodynamics. Normal prograde portal flow was confirmed by Doppler flowmeter in this series including 14 patients of more than 8 months after surgery. When the amount of nonisolated splenic vein embedded in the pancreas is minimized, portal malcirculation after distal splenorenal shunt can, to a great extent, be prevented.

Predictability and maintenance of portal flow patterns after small-diameter portacaval H-grafts in man

Patients undergoing small-diameter (8, 10, 12, and 14 mm) portacaval H-grafts were followed up to 3.5 years. Eight- and 10-mm grafts maintained prograde portal perfusion in 50% of the patients. Follow-up studies performed from 6 to 36 months after surgery show late shunt patency to be 97%. Recurrent variceal hemorrhage has not occurred in any patients. Direction of portal flow after a shunt was related to the size of the portal vein and the size of the shunt. If the shunt diameter was less than 50% that of the portal vein measured on the preoperative angiogram, portal flow was prograde. Encephalopathy rates remained significantly lower in patients with prograde flow after small diameter (8 and 10 mm) portacaval H-graft (p = .0.1). If thrombosis and encephalopathy rates remain low, the small-diameter, polytetrafluoroethylene portacaval H-graft is an attractive alternative to standard portacaval and mesocaval shunts.

Hemodynamic differences between alcoholic and nonalcoholic cirrhotics following distal splenorenal shunt--effect on survival?

The distal splenorenal shunt significantly improves 5-year survival from variceal bleeding in nonalcoholic (70%) compared to alcoholic (45%) cirrhosis patients. This study quantitates hemodynamic differences occurring in the first year after DSRS in 16 alcoholic compared to eight nonalcoholic patients. Portal venous perfusion was retained significantly better (p less than .01) by the nonalcoholic (seven of eight) than by the alcoholic (four of sixteen) patients. Mean liver blood flow (p less than 0.07), flow/unit liver volume (p less than .05), and flow required to perform a specific hepatocyte function (p less than 0.05) all increased significantly in the alcoholic compared to nonalcoholic group. Cardiac output increased significantly in the alcoholic patients (p less than 0.05), but was unchanged in the nonalcoholic patients. The alcoholic patients divided into two subsets, 11 who showed increase in flow (1082 +/- 260 to 1496 +/- 388 ml/min) and five who did not (1246 +/- 269 to 994 +/- 159 ml/min). The former had significantly (p less than 0.05) poorer hepatocyte function and had a significant (p less than 0.05) increase in flow/unit volume and flow/unit function at 1 year, which may have helped to maintain hepatocyte integrity. The latter, in parallel with the nonalcoholic patients, showed no significant change in these parameters and maintained a good functional hepatocyte mass. These data lead us to hypothesize that: 1) alcoholic liver injury has an increased risk of leading to loss of portal perfusion after DSRS, 2) as hepatocyte function falls, there is initial increase in hepatic arterial flow in alcoholic patients, triggered by increase in cardiac output, and 3) progressive injury and/or failure of the compensatory hemodynamic mechanism leads to earlier mortality in alcoholic patients. In contrast, the nonalcoholic cirrhosis patients preserve portal perfusion and maintain liver blood flow, both quantitatively and qualitatively, with retained hepatocyte function and improved survival.

Suppression of the shunt and esophageal transection. A new technique for the treatment of disabling postshunt encephalopathy

A new surgical procedure was developed for the treatment of disabling postshunt encephalopathy. This procedure consists of an esophageal transection with esophagogastric devascularization, followed by suppression of the shunt. Suppression of the shunt is performed postoperatively using external maneuvers. In the four patients treated, suppression of the shunt led to disappearance of the clinical manifestations of encephalopathy in three and to a significant improvement in one. Providing that the shunt is side-to-side, this new treatment would allow a dramatic improvement in the small number of patients in whom severe encephalopathy develops after portosystemic shunting.

Surgical management of portal hypertension and esophageal varices. 10 year experience

The results of 157 operations performed for portal hypertension and esophageal varices on 148 patients at the Cleveland Clinic in the 10 year period between 1970 and 1980 are reported. One hundred four shunt procedures and 53 ligation procedures were performed. The overall operative mortality rate of 13 percent did not differ significantly from the 11 percent rate reported from this institution in 1971. A comparatively higher rate of recurrent variceal hemorrhage and a lower rate of encephalopathy reflected our increased use of selective shunts and ligation procedures. There was no improvement in overall long-term survival, which was approximately 50 percent. The two most important factors in predicting the results of all operations for esophageal varices continue to be assessment of preoperative liver function and the timing of the operation. The best results were obtained in patients with good liver function who had an elective operation. Our data suggest that the portacaval shunt is associated with a higher incidence of late mortality, largely as a result of liver failure; therefore, our preference now is to perform a distal selective splenorenal shunt procedure whenever possible. If a selective shunt procedure cannot be performed, we advocate either a mesocaval shunt or a ligation procedure, depending on patient risk and the suitability of veins for a shunt procedure.

Long-term follow-up after a distal splenorenal shunt procedure. A clinical and hemodynamic study

Of 26 patients who underwent distal splenorenal shunting 4 or more years ago (1969 to 1978), 10 died 3 to 87 months postoperatively (mean 38.5 months). Six deaths were due to liver failure, two to hemorrhagic peptic ulcer disease (the shunt remained patent in each patient), one to brain hemorrhage, and one to sepsis. Eight of the surviving patients resumed professional activity, one showed transient signs of encephalopathy, one had a single episode of recurrent variceal bleeding that could be managed conservatively, and no patient had ascites. Eight patients were investigated angiographically and endoscopically. Preoperative and postoperative measurements of the portal vein showed a decreased diameter in five patients and no opacification in the other three 29 to 97 months after surgery. At endoscopy four patients had small residual esophageal varices, one patient had none, and the other three had large varicosities with variceal pressures between 30 and 40 cm H2O in two and above 40 cm H2O in one. Although the incidence of postoperative encephalopathy and variceal bleeding was low after distal splenorenal shunting, the operation did not prevent a decrease in hepatopetal portal flow and did not always abolish the esophageal varices.

The incidence and natural history of thrombus in the portal vein following distal splenorenal shunt

The incidence of thrombus formation in the portal vein following distal splenorenal shunt was 4% occlusive and 14% nonocclusive from 1974 to 1977, and 6% occlusive and 22% nonocclusive in 1980. The increased incidence was probably due to more aggressive ligation of collaterals on the portal vein. Ten patients with this complication were evaluated prospectively with clinical and biochemical parameters, angiography, and nutrient hepatic perfusion. In this group, one thrombus was occlusive immediately after operation, and nine were nonocclusive: eight of the latter resolved by six months, but one progressed to total thrombosis. There were no demonstrable adverse clinical or biochemical sequelae. Angiography showed continuing portal perfusion in the face of nonocclusive thrombus, but at six months there was increased collateral formation and significant (p less than 0.05) reduction in portal vein diameter, from 20 +/- 4 mm to 14 +/- 5 mm. Nutrient hepatic perfusion at six months, 896 +/- 257 ml/min, was not significantly different from that seen prior to operation, 848 +/- 92 ml/min. It is concluded that the natural history of nonocclusive portal vein thrombus after distal splenorenal shunt is resolution, and management should be expectant.

Ten years portal hypertensive surgery at Emory. Results and new perspectives

Five hundred four Shunt procedures have been done at Emory University Hospitals between 1971 and 1981 to decompress bleeding esophageal varices. This paper reviews how far the experiences of a prospective randomized study (55 patients) of distal splenorenal shunts against total shunts is supported by the nonrandomized experience (449 patients), and outlines our current methods of management dictated by this experience. The overall operative mortality for 348 selective shunts is 4.1% and for 156 nonselective shunts, 14.1%. The five-year survival following Selective shunt is 59%, and following nonselective shunt is 49%: more than half the selective shunt patients are alive, in contrast to the median survival of 44.5 months for patients having nonselective shunts. Following Selective shunt, the survival in nonalcoholic patients is significantly better than the median survival of alcoholic patients of 57 months. Encephalopathy, reported at three years after surgery in the randomized patients was significantly (p < 0.001) lower after selective shunt (12%) compared to nonselective shunt (52%): in the same population at seven years, all patients with patent nonselective shunts have clinical or subclinical encephalopathy, but only 30% of the selective shunt patients have subclinical encephalopathy. Shunt patency, immediately after surgery, is 93% following selective shunt, with only two documented late thromboses: nine of nine patients, at a mean of seven years, retain patency in the randomized study. Shunt occlusion increases with time after interposition nonselective shunts: seven of 13 are occluded at a mean follow-up of seven years in the randomized study. Portal venous perfusion is retained in 93% of patients seven to ten days after selective shunt, but in no patient with a patent nonselective shunt. Late portal perfusion is maintained in nine of the eleven patients in the randomized group studied at a mean of seven years after selective shunt. Restoration of portal perfusion has led to clearing of encephalopathy and improvement in hepatic function in six patients. The following conclusions are made: (1) selective shunts can be done with low operative mortality, and long-term patency with excellent control of bleeding; (2) hepatic portal venous perfusion has been maintained after selective shunt for ten years, and this is vital for preventing encephalopathy and maintaining hepatic function; (3) long-term survival after selective shunt is better than any reported series for nonselective shunt; and (4) selective shunts are the operative procedure of choice for variceal decompression and nonselective shunts should rarely be performed for elective decompression.