Spleen-preserving proximal splenic-left intrahepatic portal shunt for the treatment of extrahepatic 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.

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.