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Objective: Isoflurane is a volatile anesthetic that has a vasodilating effect on cerebral vessels producing a cerebral blood flow increase. Furthermore, it has been shown in animal studies that isoflurane, when used as a preconditioning agent, has neuroprotective properties, inducing tolerance to ischemia. However, it is not routinely used in neurointensive care because of the potential increase in intracranial pressure caused by the rise in cerebral blood flow. Nevertheless, subarachnoid hemorrhage patients who are at risk for vasospasm may benefit from an increase in cerebral blood flow. We measured regional cerebral blood flow during intravenous sedation with propofol and during sedation with isoflurane in patients with severe subarachnoid hemorrhage not having intracranial hypertension. Design: The study is a crossover, open clinical trial (NCT00830843). Setting: Neurointensive care unit of an academic hospital. Patients: Thirteen patients with severe subarachnoid hemorrhage , (median Fisher scale 4), monitored on clinical indication with intracranial pressure device and a thermal diffusion probe for the assessment of regional cerebral blood flow. An intracranial pressure >18 mm Hg was an exclusion criterion. Interventions: Cerebral and hemodynamic variables were assessed at three steps. Step 1: sedation with propofol 3–4 mg/ kg/hr; step 2: after 1 hr of propofol discontinuation and isoflurane 0.8%; step 3: after 1 hr of propofol at the same previous infusion rate. Cerebral perfusion pressure and arterial Pco 2 were maintained constant. Mean cerebral artery flow velocity and jugular vein oxygen saturation were measured at the end of each step. Measurements and Main Results: Regional cerebral blood flow increased significantly during step 2 (39.3 ± 29 mL/100 hg/min) compared to step 1 (20.8 ± 10.7) and step 3 (24.7 ± 8). There was no difference in regional cerebral blood flow comparing step 1 vs. step 3. No significant difference in intracranial pressure, mean cerebral artery transcranial Doppler velocity, PaCO 2 , cerebral perfusion pressure between the different steps. Conclusions: Isoflurane increases regional cerebral blood flow in comparison to propofol. Intracranial pressure did not change significantly in the population not affected by intracranial hypertension. (Crit Care Med 2012; 40:2797–2804)

Background and objective: Acute renal failure is a serious complication of cardiac surgery. We studied the long-term survival and quality of life of patients requiring renal replacement therapy after cardiac surgery, since they represent a heavy burden on hospital resources and their outcome has never been adequately evaluated. Methods: Out of 7846 consecutive cardiac surgical patients, 126 (1.6%) required postoperative renal replacement therapy: their preoperative status and hospital course was compared with patients who had no need of postoperative renal replacement therapy. A multivariate analysis identified predictors of renal replacement therapy. Longterm survival and quality of life was collected in patients who had renal replacement therapy and in casematched controls. Results: Hospital mortality in the study group was 84/126 (66.7%) vs. 118/7720 (1.5%) in the control population (P < 0.001). Patients who underwent renal replacement therapy and were discharged from the hospital (42 patients) had a reasonable long-term outcome: at 42 +/- 23 months, 30 out of 42 patients were alive, with only 3 patients complaining of limitations in daily activities. Predictors of in-hospital renal replacement therapy were: emergency surgery, preoperative renal Impairment, intra-aortic balloon pumping, reoperation for bleeding, previous cardiac surgery, female gender, low ejection fraction, bleeding > 1000 mL, chronic obstructive pulmonary disease and age. Conclusions: This study confirms that the in-hospital mortality of patients requiring renal replacement therapy is high and shows a low long-term mortality with reasonable quality of life in patients discharged from hospital alive.