Recent advances and anaesthetic considerations in corneal transplantation.

Significant surgical advances have been made recently in corneal transplantation. Penetrating keratoplasty was the dominant method from 1905, until selective lamellar keratoplasty emerged as the preferred technique over the last 20 years. Advanced techniques such as corneal limbal stem cell transplant and keratoprosthesis are also available. The major surgical complications of corneal transplantation are extrusion of ocular content and expulsive choroidal haemorrhage. It is essential for an ophthalmic anaesthetist to have a good understanding of these new surgical procedures so as to provide optimal surgical conditions. This article aims to inform anaesthetists about the recent surgical advances in corneal transplantation and explore the anaesthetic considerations of these new techniques. General anaesthesia remains suitable for a wide range of these procedures especially in repeat surgery, difficult, or prolonged procedures. Regional ophthalmic blocks are ideal for endothelial keratoplasty but can be used in penetrating keratoplasty based on individual risk-benefit assessment, and as a supplement to general anaesthesia. Topical anaesthesia provides an alternative when general anaesthesia and ophthalmic regional blocks are less desirable but overall its use is limited.

Synthesis, biological characterisation and structure activity relationships of aromatic bisamidines active against Plasmodium falciparum.

Malaria is one of the most significant tropical diseases and remains a major challenge due to the lack of a broadly effective vaccine and parasite resistance to current drugs. This means there is a need for new drug candidates with novel modes of action. Aromatic bisamidines, such as furamidine (DB75), were initially developed as anti-Trypanosoma agents however as clinical trials with furamidine highlighted potential side effects they were not pursued further in that setting. Despite apparent cytotoxicity liabilities the potency of furamidine against Plasmodium falciparum makes it a promising scaffold for the development of new anti-Plasmodium agents with improved selectivity. In this study a bisamidine compound series based on furamidine was synthesized by introducing modifications at the furan core structure and terminal amidine groups. The activity of the derived compounds was tested in vitro against drug sensitive and resistant P. falciparum lines and a human cell line (HEK293 cells) to generate anti-Plasmodium structure-activity relationships and to provide preliminary selectivity data.

Risk factors for hospital and long-term mortality of critically ill elderly patients admitted to an intensive care unit.

BACKGROUND: Data on long-term outcomes of elderly (≥65 years) patients in ICU are sparse. MATERIALS AND METHODS: Adult patients (n = 1563, 45.4% elderly) admitted over 28 months were analyzed by competing risks regression model to determine independent factors related to in-hospital and long-term mortality. RESULTS: 414 (26.5%) and 337 (21.6%) patients died in-hospital and during the 52 months following discharge, respectively; the elderly group had higher mortality during both periods. After discharge, elderly patients had 2.3 times higher mortality compared to the general population of the same age-group. In-hospital mortality was independently associated with mechanical ventilation (subdistribution hazard ratio (SHR) 2.74), vasopressors (SHR 2.56), neurological disease (SHR 1.77), and Mortality Prediction Model II score (SHR 1.01) regardless of age and with malignancy (SHR, hematological 3.65, nonhematological 3.4) and prior renal replacement therapy (RRT, SHR 2.21) only in the elderly. Long-term mortality was associated with low hemoglobin concentration (SHR 0.94), airway disease (SHR 2.23), and malignancy (SHR hematological 1.11, nonhematological 2.31) regardless of age and with comorbidities especially among the nonelderly. CONCLUSIONS: Following discharge, elderly ICU patients have higher mortality compared to the nonelderly and general population. In the elderly group, prior RRT and malignancy contribute additionally to in-hospital mortality risk. In the long-term, comorbidities (age-related), anemia, airway disease, and malignancy were significantly associated with mortality.

Environmental nicotine contamination in latent fingermarks from smoker contacts and passive smoking.

Hydrophobic silica nanopowder has been used as an effective latent fingermark development agent and subsequently as an enhancement agent in the surface-assisted laser desorption/ionisation-time of flight (SALDI-TOF) mass spectrometry for analysis of fingermark components. The technique has been used in the detection of nicotine and cotinine in the fingermarks of smokers. In order to have confidence in concluding that the nicotine in such samples is indicative of cigarette usage, it is necessary to establish that contamination by environmental contact or from hand to hand contact with smokers or from passive smoking does not lead to false identification of non-smokers as smokers. To investigate this possibility, the background level of nicotine in fingermark material from a number of commonly used places was determined. In addition, a series of experiments was carried out to assess the extent to which nicotine can be transferred through handshakes and finger transfer as well as touching of door handles. The rate of loss of nicotine from latent fingermarks was also assessed over a 24-h period under ambient laboratory conditions. Finally, a laboratory-based model system was evaluated to ascertain the possible transport of nicotine in cigarette smoke from a source to adjacent areas to simulate cross-contamination of a non-smoker by passive exposure. It was observed that person-to-person transfer from a smoker to a non-smoker can occur following handshakes but at low levels and that passive cross-contamination from contact with surfaces is possible under simulated conditions. However, levels of nicotine in the wider environment were found to be too low for detection using this technique which may reflect the half-life of nicotine in latent fingermarks which was about 11h. Likewise, transfer via smoke is possible to objects within about 0.1m of the cigarette but it is unlikely that significant secondary nicotine contamination will occur on the faces and hands of adjacent non-smokers.