The degree of the risk for developing hyperammoniemia after various vascular shunting surgeries in children with portal hypertension

BACKGROUND: Hyperammonemia and hepatic encephalopathy (HE) after portosystemic shunt surgeries in children with portal hypertension (PH) is still a pressing problem in modern pediatric surgery. AIM: To date, there are very few information in the literature on hyperammonemia prevalence after various vascular bypass surgeries in large groups of patients with PH. To study this problem is an important step in making an adequate choice of treatment modality in children with PH regarding the risk of HE development in future. METHODS: This paper analyzes the results of studies of ammonia content in venous blood in 173 children, of whom 153 had PH (most had undergone vascular bypass surgery). RESULTS: The analysis performed has shown that the risk of hyperammonemia in non-operated patients with PH is low, but it increases after certain vascular bypass surgeries on the portal system vessels. To the least extent, this applies to the physiological mesoprotal shunt (MPS) and selective distal splenorenal anastomosis (DSRA), and to the greatest extent — to total portosystemic shunts: splenorenal anastomoses (SRA) (side-to-side splenorenal anastomosis, splenosuprarenal anastomoses) and mesocaval shunt (MCS). CONCLUSION: Our findings have confirm advantages (low risk of hyperammonemia in childhood) of the mesoportal shunt and distal splenorenal anastomosis compared to splenorenal anastomoses and mesocaval H-shunt. At the same time, the study proves the effectiveness of reconstruction of the splenorenal anastomosis into a distal splenorenal anastomosis in reducing the level of ammonia in the blood (this operation was developed at the N.F. Filatov Children's City Clinical Hospital).