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Neuroprotective agents are drugs, outside of those used to re-establish perfusion to an infarcted region of the brain, that aim to salvage or protect vulnerable brain tissue during an insult. These drugs are diverse and can act by inhibiting steps in the apoptotic pathway, scavenging damaging species like free radical oxidative species, reducing inflammatory responses, and changing the extracellular environment, among other mechanisms. In this chapter, we will discuss neuroprotective drugs used in recent human clinical trials for acute ischemic stroke, their mechanisms of action, and potential avenues for future research in the discipline of neuroprotection.

Oxidative stress from surgery or critically illness has been shown to adversely contribute to morbidity and mortality. Recent studies record that oxidative stress is heightened following packed red blood cell (PRBC) transfusions and that products of oxidative stress accumulate as the PRBC ages. However, there are no studies that investigate if transfusion of aged PRBC actually increases the recipient's oxidative stress profile more than fresh PRBC.To compare the effect of fresh vs aged PRBC transfusions on the recipient's oxidative stress using an ovine model.Male sheep were transfused with either fresh (n = 6) or aged (n = 6) ovine PRBC, and serial blood samples taken. Plasma samples were analysed for lipid peroxidation using the thiobarbituric acid reactive substances (TBARS) assay. This served as an indicator of oxidative injury. Antioxidant function and trace element levels were also measured.Like human PRBC, the ovine PRBC had negligible selenium levels. Irrespective of age, PRBC transfusion was associated with reduced selenium levels and antioxidant function, which correlated with increased markers of lipid peroxidation.Transfusion of selenium poor PRBC can dilute selenium levels and compromise glutathione peroxidase antioxidant activity and thereby allow lipid peroxidation. As there was no evidence that aged PRBC induced more severe oxidative injury this suggests that selenium dilution is a key underlying mechanism. Further studies are needed to assess the impact of transfusion-related oxidative stress in massive transfusions.

BACKGROUND AND OBJECTIVES Severe transfusion-related acute lung injury (TRALI) events have been linked to donor-derived neutrophil antibodies. The journey to developing mass donor neutrophil antibody screening platforms is challenged by the fragility of neutrophils and their unique-specific antigenic characteristics. MATERIAL AND METHODS This article critically evaluates the capabilities and potential of five emerging antibody screening platforms designed to detect neutrophil reactive antibodies relevant to TRALI. They are compared with established neutrophil serological methods. RESULTS Data from two recombinant antigen platforms and a method using human neutrophil antigens-expressing KY cells indicated high specificity. Two mixed cellular flow cytometric assays have the advantage of presenting native conformation of the human polymorphonuclear neutrophil antigenic epitopes. CONCLUSIONS To date, the number and specificity of test sera applied to each platform is small. This needs to be substantially increased and further rigorous serological evaluation is yet needed to compare the sensitivity and specificity limits of each new platform with classical methods. With a limited world supply of TRALI-relevant test sera, a collaborative effort of laboratories with neutrophil and TRALI investigation expertise is required.

We report the case of the case of a 56 year old female with sepsis on a background of rheumatoid arthritis and steroid use manifesting with overt clinical features of scurvy. Ascorbic acid assays were able to demonstrate severe deficiency and confirm a diagnosis of scurvy. Clinical resolution of signs and symptoms following commencement of vitamin C replacement was rapid. The intensivist and dietitian need to consider this diagnosis even in the first world setting, particularly in the presence of sepsis, inflammatory conditions, steroid use and importantly malnutrition.

Even with the introduction of specific risk-reduction strategies, transfusion-related acute lung injury (TRALI) continues to be a leading cause of transfusion-related morbidity and mortality. Existing small animal models have not yet investigated TRALI resulting from the infusion of heat-treated supernatant from whole blood platelet concentrates. In this study, our objective was the development of a novel in vivo two-event model of TRALI in sheep.Lipopolysaccharide (LPS; 15 μg/kg) as a first event, modelled clinical infection. Transfusion (estimated at 10% of total blood volume) of heat-treated pooled supernatant from date-of-expire human whole blood platelet concentrates (d5-PLT-S/N) was used as a second event. TRALI was defined by both hypoxaemia that developed either during the transfusion or within two hours of its completion and post-mortem histological evidence of pulmonary oedema.LPS infusion did not cause lung injury itself, but did result in decreased circulating levels of lymphocytes and neutrophils with evidence of the latter becoming sequestered in the lungs. Sheep that received LPS (first event) followed by d5-PLT-S/N (second event) displayed decreased pulmonary compliance, decreased end tidal CO(2) and increased arterial partial pressure of CO(2) relative to control sheep, and 80% of these sheep developed TRALI.This novel ovine two-event TRALI model presents a new tool for the investigation of TRALI pathogenesis. It represents the first description of an in vivo large animal model of TRALI and the first description of TRALI caused by transfusion with heat-treated pooled supernatant from human whole blood platelet concentrates.

A case of initial presentation and diagnosis of hereditary coproporphyria is described, following a patient's first seizure in the surgical ward, where she had been admitted for investigation of abdominal pains. The frequency of seizures, motor neuropathy and florid visual hallucinations worsened over the subsequent days, until the definitive investigations revealed the diagnosis and specific therapies were instituted. The acute porphyrias, a rare group of conditions caused by deficiencies in enzymes involved in haem biosynthesis, are associated with significant morbidity and occasional mortality. Consideration of the diagnosis, combined with appropriate supportive and specific therapies can reduce the duration of the crisis and lessen the rates of morbidity and mortality associated with these conditions.

Summary Fifty ASA grade 1 children, who presented for dental outpatient extraction were studied. They were randomly allocated to two groups after induction: group 1 had conventional nasal mask anaesthesia and group 2 anaesthesia with a laryngeal mask. Group 2 had fewer hypoxic episodes and significantly better arterial oxygen saturations (p < 0.01). There was no difference between the groups as regards surgical access, difficulty of extraction or bleeding. The laryngeal mask appears to provide an alternative to conventional nasal mask anaesthesia, with better overall oxygenation and would seem particularly suitable for prolonged or difficult extractions.

Crystals of the title compound, CS(PPh3)2RuCl3Ru(PPh3)2Cl, are orthorhombic, space group Pn21a with a= 21·53, b= 23·40, c= 14·20 A. For 1258 independent reflections recorded on film, the final R was 0·115. Both ruthenium atoms have a distorted octahedral co-ordination, with the two octahedra sharing a common face defined by three chlorine atoms. The Ru ⋯ Ru distance is 3·35 A. Two different molecular structures may exist in the crystal, differing in the relative positions of the thiocarbonyl and terminal chloro groups of the molecule.