The presence of perchlorate in the Martian soil may limit in-situ resource utilization (ISRU) technologies to support human outposts. In order to exploit the desiccation, radiation-tolerant cyanobacterium Chroococcidopsis in Biological Life Support Systems based on ISRU, we investigated the perchlorate tolerance of Chroococcidopsis sp. CCMEE 029 and its derivative CCMEE 029 P-MRS. This strain was obtained from dried cells mixed with Martian regolith simulant and exposed to Mars-like conditions during the BIOMEX space experiment. After a 55-day exposure of up to 200 mM perchlorate ions, a tolerance threshold value of 100 mM perchlorate ions was identified for both Chroococcidopsis strains. After 40-day incubation, a Mars-relevant perchlorate concentration of 2.4 mM perchlorate ions, provided as a 60 and 40% mixture of Mg- and Ca-perchlorate, had no negative effect on the growth rate of the two strains. A proof-of-concept experiment was conducted using Chroococcidopsis lysate in ISRU technologies to feed a heterotrophic bacterium, i.e. an Escherichia coli strain capable of metabolizing sucrose. The sucrose content was fivefold increased in Chroococcidopsis cells through air-drying and the yielded lysate successfully supported the bacterial growth. This suggested that Chroococcidopsis is a suitable candidate for ISRU technologies to support heterotrophic BLSS components in a Mars-relevant perchlorate environment that would prove challenging to many other cyanobacteria, allowing a ‘live off the land’ approach on Mars.

The astonishing capability of life to adapt to extreme conditions has provided a new perspective on what ‘habitable’ means. On Earth extremophiles thrive in hostile habitats, such as hot and cold deserts or Antarctic sub-glacial lakes considered as Earth analogues of Mars and icy moons of Jupiter and Saturn. Recently desert cyanobacteria were exposed to ground-based simulations of space and Martian conditions and to real space and Martian conditions simulated in low Earth orbit using facilities attached outside the International Space Station. When exposure to such conditions does not exceed repair capabilities, more data are available regarding the physico-chemical constraints that life can withstand. When the accumulated damage exceeds the survival potential, the persistence of biomarkers contributes to the search for life elsewhere. Knowledge concerning the endurance of desert cyanobacteria under space and Martian conditions contributes to the development of life support systems.

Significant advances have been made in extracorporeal life support, which has resulted in the increased use of post-cardiotomy extracorporeal membrane oxygenation. Retrospective studies have contributed to the ongoing evolution of selection criteria for post-cardiotomy extracorporeal membrane oxygenation. Current indications include failure to wean from cardiopulmonary bypass, haemodynamic collapse, pulmonary hypertension, post-repair of hypoplastic left heart syndrome, or need for bridge to transplantation. Short- and mid-term results are improving. Ethical concerns still attend the process, however. Moral risks related to post-cardiotomy extracorporeal membrane oxygenation may be encountered before, during, and after the open heart procedure. At each stage of the decision-making process, moral risks are encountered by many factors that may result in decisions that may be contrary to the best interests of the patient, parents, or use of shared societal resources. These moral risks centre around the selection process, informed consent, decision making in the operating room, and post-operative maintenance of extracorporeal membrane oxygenation. Consideration of such risks is affected by questions of haemodynamic stability, haematologic compromise, neurologic status, and family concerns. We conclude that thorough understanding of the relevant scientific literature, heightened awareness of moral risks, and incorporation of ethical tenets in clinical deliberation will guide the clinician to do the right thing.

Background: High fidelity medical simulators (HFMS) are accepted tools for health care instruction. The use of HFMS was incorporated into an International Trauma Life Support course, and course participants were surveyed regarding attitudes toward HFMS.

Methods: Course participants, including physicians, nurses, and prehospital personnel, were given pre- and post-course questionnaires measuring their confidence in knowledge and treatment of trauma resuscitation, as well as their attitudes towards the utility and realism of immersive simulation. The participants were randomly assigned to take a course examination either before or after their simulator session.

Results: Thirteen course participants of varying backgrounds and degrees of clinical experience were surveyed and tested. All surveyed areas improved following simulator training, including comfort level with simulation as a training method (17%), perception of the realism of HFMS (15%), and reported self-confidence in knowledge, experience and training in trauma care (27%). Test scores were improved in the post-simulation group as opposed to the pre-simulation group (86% pass rate in the post-simulation test group versus 50% pass rate in the pre-simulation test group).

Conclusions: High fidelity medical simulation was accepted by medical professionals of different backgrounds and experience. Attitudes towards simulation and self-confidence improved after simulator sessions, as did test scores, suggesting improved comprehension and retention of course materials. Further testing is required to validate the findings of this small, observational study.

Many individuals have tube feeding implemented in the end stages of life. It is also common to have surrogates making life support decisions for others. When family members are placed in the role of decision-maker for an incompetent patient, what factors influence life support decisions? A case study and ethnomethodological inquiry provide an in-depth understanding of factors that influenced one daughter in her decision to have tube feeding implemented for her incompetent and severely debilitated mother. The decision was difficult and constituted a time of crisis. Unfortunately, the most influential factors in decision-making were: (a) urgency in the face of impending death, (b) lack of insight into the mother's values and preferences in relation to life support through tube feeding, (c) lack of knowledge over what tube feeding involved, and (d) the belief that tube feeding would not prolong her mother's life and suffering. Nine other, less influential, factors were also found. Improving the sensitivity of health care professionals to the agony of decision-making and to the decision-making process for life support are the major focuses of this paper.

Compelling anecdotal evidence exists for the potentially lifesaving benefits of mechanical external chest compression (MECC), but no published trials of the technique exist. The history and technique for MECC are discussed and illustrated by a case report. Although the technique is not discussed in the Resuscitation Guideline 2000, and the need for it within the intensive care unit has reduced, the use of MECC will have its greatest impact when initiated in the prehospital setting for patients suffering from severe, sudden-onset, asphyxic asthma.

Hazardous materials (HAZMAT) carry many inherent dangers. Such materials are distributed widely in industrial and military sites. Toxic trauma (TT) denotes the complex of systemic and organ injury caused by toxic agents. Often, TT is associated with other injuries that also require the application of life-support techniques. Rapid onset of acute respiratory failure and consequent cardiovascular failure are of primary concern. Management of TT casualties is dependent upon the characteristics of the toxic agents involved and on the demographics surrounding the HAZMAT incident.

Agents that can produce TT possess two pairs of salient characteristics: (1) causality (toxicity and latency), and (2) EMS system (persistency and transmissibility). Two characteristics of presentations are important: (1) incident presentation, and (2) casualty presentation. In addition, many of these agents complicate the processes associated with anaesthesia and must be dealt with. Failure of recognition of these factors may result in the development of respiratory distress syndromes and multiorgan system failure, or even death.

In a Swedish nation-wide study, 1196 members of the general public, and 121 physicians and 339 nurses drawn from 29 intensive care units were questioned about the use of ventilator treatment for severely ill patients. Response rates were 64%, 88% and 86%, respectively. Two typical case history scenarios were presented: one describing a conscious and competent patient with pneumonia and severe cancer, and the other describing a patient who had been comatose for 1 month following head trauma. In the case of the cancer patient, 49% of the general public, 63% of the physicians and 59% of the nurses answered that theywould wish that the ventilator treatment be discontinued, if they were the patient. In the case of the comatose patient, 48% of the general public, 82% of the physicians and 70% of the nurses answered that they would wish that the ventilator treatment to be discontinued, if they were a relative of the patient. Respondents own preferences, in the three groups,for life support favoured withdrawal of ventilator treatment.