Gastroportal shunt for portal hypertension in children

Rex Shunt for Extra-Hepatic Portal Venous Obstruction in Children

Rex shunt, which was first put in use in 1992, has been considered as an ideal surgical method for the treatment of extra-hepatic portal venous obstruction (EHPVO) due to its reconstruction of the hepatopetal portal blood flow. However, despite its long tradition, there are only a few reports about the application and advances in Rex shunt for the treatment of EHPVO in children. In this paper, we summarized the literature related to Rex shunt and discussed the new advances of Rex shunt in the following aspects: surgical method of Rex shunt, the indications of Rex shunt, the strengths of Rex shunt, the effectiveness of Rex shunt, factors affecting the efficacy of Rex shunt, methods that improve the prognosis of Rex shunt, and treatment strategy for recurrence after Rex shunt.

Meso-Rex bypass shunt vs. transposition shunt for cavernous transformation of portal vein in children

BACKGROUND

Cavernous transformation of the portal vein (CTPV) causes portal hypertension in children. Among Meso-Rex treatments, it is unclear whether the Meso-Rex bypass shunt (MRB) or the Meso-Rex transposition shunt (MRT) offers lower postoperative morbidity. Our objective was to evaluate postoperative outcomes, comparing MRB and MRT for children with CTPV.

METHODS

A retrospective study was conducted on children undergoing Meso-Rex for CTPV from January 2010 to December 2020. The primary outcome was shunt complications, including shunt stenosis and thrombus. The secondary outcome was re-operation.

RESULTS

Of the 43 patients included, 21 underwent MRT and 22 underwent MRB. MRT was associated with a higher rate of shunt complications when compared to MRB (23.8 vs. 9.1%, p = 0.191). The patients exhibited a higher rate of re-operation under the MRT than under the MRB (19 vs. 4.5%, p = 0.138). The operative time in the MRT group was significantly shorter than in the MRB group. Compared to MRT, the reduction in the length and thickness of the spleen was significantly greater in the MRB group. The increases in platelets were significantly higher in the MRB group than in the MRT group. The postoperative shunt velocity of MRB was notably faster than MRT. There was no significant difference in postoperative portal pressure between the two groups (p > 0.05).

CONCLUSION

Both MRB and MRT result in acceptable postoperative outcomes, but MRT is associated with higher post-shunt complications, which often increase the re-operation rate. This study suggests that MRB may offer advantages for children with CTPV.

Splenectomy with proximal spleno-left portal shunt for extrahepatic portal vein obstruction in children

PURPOSE

To report our initial experience with splenectomy and proximal spleno-left portal shunt as an alternative to the standard Rex shunt, when not applicable, in children with Extrahepatic Portal Vein Obstruction (EHPVO).

METHODS

Patients from March 2015 till September 2018, with EHPVO not suitable for Rex shunt or whose caregivers refused to consent for Internal Jugular Vein (IJV) dissection were assessed and prepared for splenectomy with proximal spleno-left portal shunt. The operative technique includes splenectomy, freeing of the splenic vein from the pancreatic bed till its junction with the inferior mesenteric vein, and then anastomosis with the intrahepatic left portal vein at the Rex recess. A distal lieno-renal shunt was performed in one patient and was excluded from the study.

RESULTS

A total of 14 patients (mean age: 4.6 years) underwent splenectomy with proximal spleno-left portal shunt during the study period. The mean operative time was 246 min, while the mean postoperative hospital stay was 4.1 days. The patients' follow up period ranged from 6 to 42 months (median: 19.6 months). Only two patients had a single attack of variceal bleeding, 2 and 2.5 months postoperative respectively, and required endoscopic management with no further bleeding episodes. While the rest of patients showed an improvement of their variceal grades after the surgery.

CONCLUSION

Splenectomy with proximal spleno-left portal shunt seems to be a valuable alternative to the standard Rex shunt in treatment of children with EHPVO unsuitable for or following unsuccessful Rex shunt.

LEVEL OF EVIDENCE

IV.

Imaging features and clinical relevance of portal venous systems shown by extrahepatic portal angiography in children with extrahepatic portal venous obstruction

OBJECTIVE

This study investigated the morphologic changes of portal cavernoma in children with extrahepatic portal venous obstruction and explored the relationship with prognosis.

METHODS

From February 2008 to October 2017, there were 107 patients with cavernous transformation of the portal vein admitted to our hospital. Rex shunts were performed in 99 cases, Warren shunts in 7 cases, and laparoscopic splenic vessel ligation in 1 case. Intraoperative superior mesenteric venography was used to determine the structure of the portal venous system. According to the morphologic features of the portal vein shown by portal venography, groups were assigned as follows: patients with the cotton form of portal cavernoma; patients with visible collateral veins of portal cavernoma; patients with and without a visible left gastric vein; and patients with and without a clearly visible intrahepatic portal vein. The preoperative and postoperative portal pressure, preoperative incidence of esophageal varices, time at onset, incidence of postoperative rebleeding, preoperative and postoperative size of the spleen, and age at time of operation were compared between these groups.

RESULTS

The preoperative incidence of esophageal varices, time at onset, postoperative size of spleen, and age at time of operation were significantly lower in the group with the cotton form than in those with visible collateral veins (P < .05). There was a significant correlation between the visible left gastric vein and esophageal varices (P = .002). The time at onset, preoperative and postoperative size of the spleen, and age at time of operation were markedly lower in the group with a good visible intrahepatic portal vein than in those without a clearly visible intrahepatic portal vein (P < .05). The visible left gastric vein was notably associated with the performance of a gastroportal shunt (P = .000), and the group with a visible left gastric vein had a higher ratio of children undergoing a gastroportal shunt.

CONCLUSIONS

The cotton form, an early-stage manifestation of cavernous transformation of the portal vein, typically occurs in younger children with a shorter time to onset. Children with the cotton form of portal cavernoma typically have a better prognosis after Rex shunt.

The role of surgical shunts in the treatment of pediatric portal hypertension

BACKGROUND

Portal diversion by surgical shunt plays a major role in the treatment of medically refractory portal hypertension. We evaluate our center's experience with surgical shunts for the treatment of pediatric portal hypertension.

METHODS

All patients who underwent surgical shunt at a single institution from 2008 to 2017 were reviewed. The primary outcome was intervention-free shunt patency.

RESULTS

In this study, 34 pediatric patients underwent portal shunt creation. The median age was 7.7 years (interquartile range 4.3-12.0). Twenty-nine patients (85%) had prehepatic portal hypertension and 5 patients (15%) had intrahepatic portal hypertension. The primary manifestations of portal hypertension were esophageal varices (97%) and gastrointestinal bleeding (77%). Eighteen patients (53%) underwent meso-Rex bypass, 10 patients (29%) underwent splenorenal shunt, and 6 patients (18%) underwent mesocaval shunt. Outcomes were notable for minimal wound complications (9%), rebleeding events (12%), and mortality (3%). In the postoperative setting, 10 patients (29%) experienced a shunt complication (occlusion or stenosis), 4 of which occurred in the early postoperative period and required urgent intervention. The 1-year and 5-year "primary patency" patency rates were 71% and 66%, respectively.

CONCLUSION

Children suffer significant morbidity from the sequelae of portal hypertension. Our experience reinforces the feasibility of surgical shunts as an effective treatment option associated with low rates of morbidity and mortality.

Portal-to-right portal vein bypass for extrahepatic portal vein obstruction

OBJECTIVE

Rex shunt (mesenteric-to-left portal vein bypass) is considered a more physiologically rational treatment for EHPVO than other portosystemic systemic shunts in children. However, about 13.6% of children with EHPVO do not have usable left portal veins and up to 28.1%. Rex operations in children are not successful. Hence, a Rex shunt in these children was impossible. This study reports a novel approach by portal-to-right portal vein bypass for treatment of children with failed Rex shunts.

MATERIAL AND METHODS

Eight children (age 6.1years, range 3.5-8.9years) who underwent Rex shunts developed recurrent gastrointestinal bleeding and hypersplenism 13months (11-30months) postoperatively. After ultrasound confirmation of blocked shunt, they underwent exploration. Three patients were found to have right portal vein agenesis. Five patients (62.5%) were found to have the patent right portal vein, with the diameter of 3-6mm. Four patients underwent bypass between the main portal vein in the hepatoduodenal ligament and the right portal vein by interposing an inferior mesenteric vein autograft, whereas the remaining patient underwent a bypass using ileal mesenteric vein autograft.

RESULTS

The operations took 2.3h (1.9-3.5h). The estimated blood loss was 50ml (30-80ml), with no complication. The portal venous pressure dropped from 34.6cmH₂O (28-45 cmH₂O) before the bypass to 19.6cmH₂O (14-24cmH₂O) after the bypass. The 5 patients were followed up for 10.2months (4-17months) and the post-operative ultrasound and CT angiography confirmed the patency of all the grafts and disappearance of the portal venous cavernova in all five patients.

CONCLUSION

The portal-to-right portal vein bypass technique is feasible and safe for treatment of children with EHPVO who have had failed Rex shunts. Our preliminary result indicates that this technique extends the success of Rex shunt from left portal vein to right portal vein and open a new indication of physiological shunt for some of the children who not only have had failed Rex shunts or but also are not suitable for the Rex shunts.

TYPE OF STUDY

Treatment study.

LEVEL OF EVIDENCE

Level IV.

Postoperative enlargement and prognostic effects of portal venous bypass grafts in children undergoing Rex shunt

OBJECTIVE

Patency of the bypass vein after a Rex shunt is an important indicator of prognosis. However, there is no report about the change of caliber of the bypass vein after a Rex shunt. The aim of this study was to identify postoperative changes of the bypass vein and to assess the relationship with prognosis.

METHODS

Between October 2008 and October 2016 in our center, 114 children were diagnosed with extrahepatic portal venous obstruction. The portal cavernoma-portal bypass with interposition of grafted portal vessels was performed in 31 children, the gastroportal shunt was performed in 54 children, and other Rex shunts were performed in another 29 children. At follow-up, the patency and diameter of the bypass vein were assessed with ultrasound and computed tomography. The intraoperative and postoperative diameters of the bypass vein were compared to identify postoperative changes of the bypass vein. Prognosis was compared between children with and children without an enlarged bypass vein.

RESULTS

The caliber of the bypass vein was enlarged in 50% of children (40/80) at 6 months postoperatively. The postoperative incidences of rebleeding and esophageal varices were significantly lower in children with an enlarged bypass vein than in those without (P < .05). Postoperatively, the reduced splenic size was significantly higher in children with an enlarged bypass vein than in those without (P < .05). The postoperative increase in platelet count in children with an enlarged bypass vein was significantly higher than in those without (P = .006). There was no significant difference in the flow velocity of the bypass vein between children with and children without an enlarged bypass vein (P = .133). The portal pressure was significantly reduced after surgery in children with an enlarged bypass vein than in children without an enlarged bypass vein (P = .017).

CONCLUSIONS

The caliber of the bypass vein increases in 50% of children after a Rex shunt using a grafted portal vessel, which is related to a better prognosis.

Surgical treatment for rebleeding caused by bypass failure after Rex shunt: re-Rex shunt or Warren shunt?

PURPOSE

Although Rex shunt is an effective treatment for extrahepatic portal venous obstruction (EHPVO), 4-20% children develop rebleeding postoperatively. This study was used to evaluate the surgical treatment of rebleeding after Rex shunt in our center.

METHOD

From June 2008 to Jan 2017, 12 of 122 children with EHPVO underwent a second operation due to graft stenosis and occlusion after Rex shunt in our center. The abdominal ultrasound and computed tomography (CT) showed the occlusion of bypass vein in nine children, stenosis of bypass vein in two children, and the patency of bypass vein in one child with dysplasia of intrahepatic portal vein. A re-Rex shunt was performed in eight children, of which one child required conversion to Warren shunt due to postoperative rebleeding. Five children underwent Warren shunt due to a narrowed left portal vein shown by intraoperative portal angiography and surgical exploration. All patients were followed up in this study.

RESULTS

The postoperative incidences of re-bleeding and esophageal varices in children with Warren shunt were significantly lower than those in children undergoing re-Rex shunt (P = 0.027 and 0.015). After a second operation, the rate of bypass vein patency in children with re-Rex shunt was lower than that in children with Warren shunt (50 vs. 100%). The postoperative reduced size of spleen in children undergoing Warren shunt was significantly higher than that of children undergoing re-Rex shunt (P < 0.05).

CONCLUSIONS

Comparing to re-Rex shunt, Warren shunt was a better treatment for rebleeding caused by bypass failure after Rex shunt.

Diagnosis and treatment guidelines for aberrant portal hemodynamics: The Aberrant Portal Hemodynamics Study Group supported by the Ministry of Health, Labor and Welfare of Japan

Idiopathic portal hypertension (IPH), causing aberrant portal hemodynamics, is a disease with an as yet unidentified cause and no established treatment protocol. The Japanese research group on IPH in Japan was set up in 1975 by the Ministry of Health, Labor and Welfare. Extrahepatic portal obstruction and Budd-Chiari syndrome (BCS) have since been added to the group's research subjects. The aims of the research group are to accurately evaluate the current status of the three diseases in Japan, elucidate their etiology and pathogenesis, and develop new treatments. Due to the long-term efforts of the Japanese research group, aberrant portal hemodynamics has been investigated in a variety of aspects, from epidemiological and pathological studies to molecular biology analyses. As a result, it has been shown that there are abnormal genes in the liver, specific for IPH. In addition, pathological findings of BCS were internationally compared and the difference in findings between Japan and Europe (or North America) has been clarified. Furthermore, it was found that complication rates of hepatocellular carcinoma in BCS were higher in Japan. Based on the research, "Diagnosis and treatment of aberrant portal hemodynamics (2001)", including diagnostic criteria for aberrant portal hemodynamics, was published in 2001. In 2013, it was revised to "Diagnosis and treatment guidelines for aberrant portal hemodynamics (2013)" after the incorporation of diagnosis and treatment in accordance with its current status.

Laparoscopic splenic vessels ligation as a treatment of hypersplenism and thrombocytopenia in children

BACKGROUND

Splenectomy and partial splenic embolization as the surgical approach in the treatment of hypersplenism and thrombocytopenia have been reported. However, there are still some disadvantages in the application of these techniques. In this article, we propose a new technique for the treatment of hypersplenism and thrombocytopenia in children and report our preliminary experience.

METHODS

From Aug 2014 to Dec 2014, four children with hypersplenism and three children with idiopathic thrombocytopenic purpura were treated in our hospital. Laparoscopic splenic vessels ligation was performed in all patients. The gastric wall was suspended to expose the pancreatic tail and spleen, and the splenic artery was ligated at the superior border of the pancreas. The splenic venous branches were dissected and ligated at the splenic hilum using the Hem-o-lok.

RESULTS

The laparoscopic splenic vessels ligation was successfully performed in all patients. The average operative time was 126 min (range 120-150 min). No patient required transfusion, and the length of hospital stay varied from 4 to 11 days (mean 6.6 days). The patients were followed up for 6-10 months (mean 8.5 months). The complete blood counts were within normal range. The size of spleen decreased postoperatively. The partial splenic infarction and the reduction in splenic blood flow were confirmed in all patients by postoperative ultrasound and CT.

CONCLUSIONS

The laparoscopic splenic vessels ligation is a feasible option for treating hypersplenism and thrombocytopenia in children.

Spleen-preserving proximal splenic-left intrahepatic portal shunt for the treatment of extrahepatic portal hypertension in children

PURPOSE

The Rex shunt has been employed successfully to treat patients with extrahepatic portal hypertension. In the conventional Rex shunt, the internal jugular vein is used as a venous graft. Inevitably, such a procedure requires neck exploration and sacrifice of the internal jugular vein. The authors describe a novel adaptation of spleen-preserving spleno-Rex bypass, successfully carried out in children with extrahepatic portal hypertension.

METHODS

The mean age of the four patients (1 boy, 3 girls) was 46 months at the time of operation. All children had a history of upper gastrointestinal bleeding, and suffered from splenomegaly and hypersplenism. Spleen-preserving proximal splenic-left intrahepatic portal shunt was performed in all patients. The splenic artery and vein were ligated at the splenic hilum, and the splenic vein was completely separated from the bed of the pancreas to its junction with the inferior mesenteric vein. The freed splenic vein was anastomosed to left portal vein. The short gastric and left gastroepiploic vessels were kept intact to supply and drain the spleen. All patients were followed-up for 7-33 months (median: 21.5 months).

RESULTS

The spleen-preserving spleno-Rex bypass was successfully performed in all 4 patients. The median operative time was 225 min (range: 215-260 min). One patient received blood transfusion, and the postoperative length of hospital stay varied from 4 to 6 days (median: 4.5 days). Intraoperative portal venous angiography demonstrated the patency of the shunt in all patients. Postoperatively, the complete blood count normalized and the biochemistry tests were within normal range. Postoperative ultrasound confirmed shunt patency and satisfactory flow in the proximal splenic-portal shunt in each patient. The size of the spleen decreased and there was no recurrence of variceal bleeding.

CONCLUSIONS

The spleen-preserving spleno-Rex bypass is a viable option to treat EHPVO in children.