Gastric intramucosal pH predicts outcome after surgery for ruptured abdominal aortic aneurysm

Objective:The mortality associated with repair of ruptured abdominal aortic aneurysms (RAAA) remains obstinately high and many deaths result from multiple organ failure which is likely to be related to splanchnic ischaemia. The aim of this study is to investigate the importance of splanchnic ischaemia in determining outcome from RAAA by comparing gastric intramucosal pH with other methods of assessing the adequacy of splanchnic oxygenation.Design and setting:Prospective cohort of patients following surgery for RAAA admitted to the Intensive Care Unit of Guy's Hospital, London.Outcome measures:Gastric intramucosal pH (pHim) and global haemodynamic, oxygen transport and metabolic variables were measured on admission, at 12 h and at 24 h after admission. Results were compared between survivors and non-survivors and Receiver Operating Characteristic (ROC) curves were constructed to assess the ability of each measurement to predict outcome.Results:The median 24 h APACHE II was 18 and the ICU mortality 45.5%. Gastric pHim was significantly higher in survivors than non-survivors at 24 h (7.42 vs. 7.24, p < 0.01). In survivors who had a low intramucosal pH (pHim) on admission there was a significant improvement over the first 24 h (7.26 to 7.40, p < 0.05), whereas in patients who subsequently died, and had a normal pHim on admission, there was a significant fall in pHim (7.35 to 7.16, p < 0.05). ROC curves showed that gastric pHim was the most sensitive measurement for predicting outcome in these patients.Conclusions:Gastric intramucosal pH is the most reliable indicator of adequacy of tissue oxygenation in patients with RAAA, suggesting that splanchnic ischaemia may have played an important role in determining survival

Mortality after discharge from intensive care

No abstract available

Portal hypertension in acute liver failure

Twenty five patients with acute liver failure were measured for hepatic venous pressure gradient as an index of portal pressure during the course of a transjugular liver biopsy. Hepatic venous pressure gradient ranged from 4 to 24.5 mm Hg with a mean of 12.8 (5.3) mm Hg (normal values less than 5 mm Hg). All patients but one had increased portal pressure gradient. Portal hypertension correlated with the degree of architectural distortion of the liver, as suggested by a direct correlation between hepatic venous pressure gradient and the area of reticulin collapse, evaluated by means of a morphometric analysis on Sirius red stained liver slides (r = 0.43, p less than 0.05). Hepatic venous pressure gradient was significantly higher in patients with ascites (15.1 (5) mm Hg, n = 15) or renal failure (14.4 (5.3) mm Hg, n = 16) than in those without (9.3 (3.4) mm Hg and 10.1 (4) mm Hg, respectively; p less than 0.05). Portal hypertension was associated with systemic vasodilation and a hyperkinetic circulatory state, with decreased arterial pressure, and peripheral resistance and increased cardiac output

The Effect of Government Advertising Policies on the Market Power of Cigarette Firms

We estimate market power among cigarette manufacturers over 1952–1984, a period of uniform pricing. We apply the Bresnahan approach; adjust it to the firm level; employ a dynamic model with habit persistence; and add an advertising equation, which helps identify the parameters, increase degrees of freedom, and constrain parameters so we can interpret our results at the firm level, despite the fact that the equations conform to what we might see in a market model. We consider effects of government interventions upon demand and market power and find, for instance, that the 1971 broadcast advertising ban decreased market power. Copyright Springer 2006Advertising policies, broadcast advertising ban, cigarettes, market power, JEL classification, L1, L51, L66, M37,