Selectivity of the distal splenorenal shunt.

The distal splenorenal shunt is less likely to provoke encephalopathy than conventional shunting procedures, and it may offer a survival advantage for certain cirrhotic individuals, presumably because of its selective nature. This study suggests that the distal splenorenal shunt, even with exceptional efforts to achieve portomesenteric-gastrosplenic (PM-GS) disconnection, is not nearly as selective as it originally was assumed to be. In 11 patients intraoperative pressure determinations showed a significant decrease in portal pressure after end-to-side distal splenorenal anastomosis and no restoration of portal pressure after PM-GS disconnection. Measurements of flow through the shunt were comparable to those reported for portacaval shunts, and shunt flow was not decreased significantly by PM-GS disconnection. Postoperative angiography showed some PM-GS collateral in 17 of 18 patients, and later angiographic studies showed a tendency for progressive collateral development and consequent loss of hepatopetal portal perfusion. The advantages of the distal splenorenal shunt must accrue from gradual, as opposed to abrupt, portal deprivation, rather than from lasting selectivity.