Pathogenesis of osteoarthrosis.

patients had alcoholic liver disease, many with grossly abnormal liver function, and many were in the upper age range for the condition. As a group such patients must form a poorrisk category whatever treatment is offered. The ultimate result in patients with alcoholic liver disease is influenced by whether or not they continue drinking, a fact which (as all concerned with such patients would agree) is very difficult to establish with certainty. In many cases haemorrhage had not been confirmed by endoscopy, though that should be mandatory in patients with alcoholic liver disease, who may often have alternative sites of bleeding such as peptic ulcers and gastric erosions. " Despite the results of the recent trials we remain ignorant about the virtues of portacaval shunting for younger and non-alcoholic patients with portal hypertension who present with repeated episodes of variceal haemorrhage. The natural history of variceal bleeding is variable and depends on the disease category. Studies from the Mayo clinic" have shown that patients with portal hypertension secondary to chronic active hepatitis but on steroid treatment have a low incidence of recurrent variceal haemorrhage. Patients with extrahepatic portal hypertension have a relatively good prognosis for each episode of haemorrhage and should also be considered as a separate group. Whether selection of those patients who will benefit from portacaval shunting will ever be possible is conjectural, for attempts based on haemodynamic or detailed biochemical investigations have generally failed to help. For the present a reasonable policy is to offer elective PCA only to the small group of younger patients (aged 20-30 years) with non-alcoholic portal hypertension and reasonably preserved liver function who have had at least two confirmed episodes of bleeding from gastro-oesophageal varices during the previous 12 months. This leaves a majority of patients, many with severely impaired liver function, in whom recurrent variceal haemorrhage remains a problem. What other forms of surgery can be offered? Aiming to minimise the risk of post-shunt encephalopathy, Warren"' has devised a technique for decompressing varices termed the distal splenorenal shunt. Here blood is selectively shunted from the system of vessels supplying the varices but not from the portal system. He also attempted to predict which patients would develop hepatic encephalopathy by monitoring the mean rate of urea synthesis. Initial reports of this procedure have been encouraging: rates of postoperative bleeding and encephalopathy have been very low. " In the most recent analysis Britton'2 reviewed 154 patients after procedures of selective shunting up to 96 months and reported an encephalopathy rate of only 8(1. Direct ligation or transection of varices remains lifesaving as an emergency procedure in a few cases of continuing severe haemorrhage that cannot be controlled by Sengstaken tube, but it has lost its initial popularity as an elective procedure because of the high rate of further bleeding. This assessment was confirmed in a recent paper by Cooperman,':3 who found that every one of a group of non-cirrhotic patients with portal hypertension bled again despite ligation of the varices. Recently, more conservative surgical procedures have been described, such as attempts directly to thrombose the varices or the vessels supplying them. An oesophagogastroscope is used to inject a sclerosing agent directly into the varices. Regular follow-up of the patient is needed with repeated injections until the varices have been obliterated. A second technique uses a transhepatic approach with selective catheterisation of the left gastric and short gastric veins and injection of dextrose, thrombin, and gelatin foam'4 to induce thrombosis. Unfortunately there seems to be a high frequency of recanalisation and further bleeding. Both techniques require expertise if complications are to be avoided and they are available in only a few specialised centres. Controlled trials are now in progress. Finally, some workers would argue that liver transplantation (the results of which have improved greatly during the past 18 months) may be the only possible approach in a few selected young patients with endstage cirrhosis in whom repeated bleeding from massive varices remains uncontrolled.