A new operation for selective decompression of portal hypertension in children with diminutive splenic veins is desired. The operation, direct splenocaval shunt (S-D-SCS), produces transplenic decompression of gastric-esophageal varices without interfering with the existing portal flow status in any significant measure. The proximal free end of the inferior vena cava (IVC) is joined to the side of the splenic vein, which is ligated on the hepatic side of the anastomosis. Addition of partial gastric devascularization completes the operation. Technically the operation is simple and easily executable. Because the IVC is utilized in creation of the shunt, anastomoses as large as 1.72 +/- 0.45 cm in diameter are obtained with splenic veins of less than 1 cm in diameter. S-D-SCS was performed in 10 children with a mean age of 9.25 +/- 3.36 years and a mean splenic vein size of 8.2 +/- 2.25 mm in diameter. Shunt thrombosis occurred in one patient who died. Nine patients survived the operation and obtained class A surgical results over a follow-up period of 7 to 12 months. None rebled, developed postshunt encephalopathy (PSE), or manifested laboratory evidences of protein intolerance. Insignificant alterations were brought about in liver blood flow (EHBF) and sinusoidal pressure (CSP); portal blood flow to the liver was maintained; and liver function tests were preserved at preoperative levels. The surgical results were superior to those following mesentericocaval and portacaval shunts in our earlier series of children with comparable mean age, body weight, and postoperative interval when studied functionally. About 30% of all of the shunt patients died of liver failure within weeks or months after the operations, and an additional 30% of the patients developed clinically significant PSE over variable periods of follow-up. These high mortality and morbidity rates were preceded by significant reductions in EHBF and CSP and concomitant precipitation of liver function abnormalities.