Medical preparedness, incidents, and group dynamics during the analog MARS2013 mission.

Participants on spaceflights and international scientific analog Mars missions can encounter medical incidents (accidents, illnesses) and psychological issues (e.g., stress, group interaction, sleep disturbance, emotions). The aim of this study was to examine these parameters in a field crew living in a desert environment similar to Mars (Group 1) and in Mission Support Center (MSC) personnel on "Earth" (Group 2) during a 4-week mission. Of the 107 medical interventions in the field, 73 mainly minor incidents together with four near accidents and 29 medical checkup interventions were recorded. Of the 32 medical interventions, medical treatments for 23 incidents of minor severity were necessary in Group 2. Injuries (Group 1: 1.4/100 h, Group 2: 0.1/100 h) were significantly increased in the field, and illnesses (Group 1: 0.3/100 h, Group 2: 3.0/100 h) in the MSC personnel. Causes of accidents and illnesses are described. Psychological results show that emotions and stress remained stable in both groups. Sympathy, social competence, teamwork, and leadership showed high scores. These scores were lower on "Earth" but significantly increased in the last weeks. The Sahara's nighttime coldness was reflected in an increased wake-up frequency, and a longer sleeping time peaked in the third week, probably as a result of overfatigue. MARS2013 was a successful mission with highly motivated participants and minor medical incidents. For future analog missions and possibly long-distance open-space missions, some recommendations in terms of medical and psychological preparedness are made to reduce risks for field crew members and MSC personnel.

Mode of anesthesia, mortality and outcome in geriatric patients.

BACKGROUND: In older non-cardiac surgery patients, the influence of the mode of anesthesia on late-term outcome (rehabilitation, mobility, independence) is a controversial issue in the medical literature. In light of an aging society, this review assessed the association between regional (RA), local (LA) and general anesthesia (GA) and mortality and morbidity. METHODS: A literature search within the PubMed and Cochrane databases yielded 47 clinical trials and 35 reviews/meta-analyses published between 1965 and 2013. Potential outcome-influencing factors such as mortality, risk factors, early complications (e.g. postoperative confusion, aspiration, vomiting), adverse events (e.g. deep vein thrombosis, pulmonary embolism), discharge, rehabilitation and mobilization were evaluated in relation to the mode of anesthesia (RA, LA or GA). RESULTS: The current literature contains 82 references covering 74,476 non-cardiac surgery patients. Analysis shows that the particular mode of anesthesia influences mortality and morbidity. RA is associated with reduced early mortality and morbidity, e.g. fewer incidents of deep vein thrombosis and less acute postoperative confusion, as well as a tendency toward fewer myocardial infarctions and fatal pulmonary embolisms. GA has the advantages of a lower incidence of hypotension and reduced surgery time. CONCLUSION: Strictly speaking, true anesthesia-related complications appear to be rare and many adverse outcomes may be multifactorial. Postoperative complications are largely related to the perioperative procedure and not to the anesthesia itself. GA and RA are both useful for older non-cardiac patients, but for some procedures, e.g. hip fracture surgery, RA seems to be the technique of choice. The mode of anesthesia may only play a secondary role in mobility, rehabilitation and discharge destination. In general, due to the many different possible outcomes--which are often very difficult or impossible to compare--no other specific recommendations can be made with regard to the type of anesthesia to be preferred for older non-cardiac patients.

Neuroaxial versus general anaesthesia in geriatric patients for hip fracture surgery: does it matter?

The influence of the mode of anaesthesia on outcome of geriatric patients with hip fractures is a controversial issue in the medical literature. In the light of an ageing society, a conclusive answer to this question is of growing importance. The purpose of this review was to assess the effect of neuroaxial and general anaesthesia on mortality and morbidity in geriatric patients sustaining a hip fracture. Following a current literature search within the Pubmed and Cochrane database (1967-2010), 34 randomised controlled trials, 14 observational studies and eight reviews/meta-analysis publications were included. Potentially outcome-influencing factors such as mortality, deep vein thrombosis, pulmonary embolism, postoperative confusion and other anaesthesia-related outcomes were evaluated. After analysing the current literature with 56 references, covering 18,715 patients with hip fracture, it can be concluded that spinal anaesthesia is associated with significantly reduced early mortality, fewer incidents of deep vein thrombosis, less acute postoperative confusion, a tendency to fewer myocardial infarctions, fewer cases of pneumonia, fatal pulmonary embolism and postoperative hypoxia. General anaesthesia has the advantages of having a lower incidence of hypotension and a tendency towards fewer cerebrovascular accidents compared to neuroaxial anaesthesia. Otherwise, general anaesthesia and respiratory diseases were significant predictors of morbidity in hip fracture patients. These data suggest that regional anaesthesia is the preferred technique, but the limited evidence available does not permit a definitive conclusion to be drawn for mortality or other outcomes. For hip fracture surgery, the choice of anaesthesia (general or neuroaxial) is made by the anaesthesiologist and is based on the patient's preference, comorbidities, potential general postoperative complications and the clinical experience of the anaesthesiologist. The overall therapeutic approach in hip fracture care should be determined jointly by the orthopaedic surgeon, the geriatrician and the anaesthesiologist (multidisciplinary approach).