Brine-driven destruction of clay minerals in Gale crater, Mars.

Mars' sedimentary rock record preserves information on geological (and potential astrobiological) processes that occurred on the planet billions of years ago. The Curiosity rover is exploring the lower reaches of Mount Sharp, in Gale crater on Mars. A traverse from Vera Rubin ridge to Glen Torridon has allowed Curiosity to examine a lateral transect of rock strata laid down in a martian lake ~3.5 billion years ago. We report spatial differences in the mineralogy of time-equivalent sedimentary rocks <400 meters apart. These differences indicate localized infiltration of silica-poor brines, generated during deposition of overlying magnesium sulfate-bearing strata. We propose that destabilization of silicate minerals driven by silica-poor brines (rarely observed on Earth) was widespread on ancient Mars, because sulfate deposits are globally distributed.

Evidence for Multiple Diagenetic Episodes in Ancient Fluvial-Lacustrine Sedimentary Rocks in Gale Crater, Mars.

The Curiosity rover's exploration of rocks and soils in Gale crater has provided diverse geochemical and mineralogical data sets, underscoring the complex geological history of the region. We report the crystalline, clay mineral, and amorphous phase distributions of four Gale crater rocks from an 80-m stratigraphic interval. The mineralogy of the four samples is strongly influenced by aqueous alteration processes, including variations in water chemistries, redox, pH, and temperature. Localized hydrothermal events are evidenced by gray hematite and maturation of amorphous SiO2 to opal-CT. Low-temperature diagenetic events are associated with fluctuating lake levels, evaporative events, and groundwater infiltration. Among all mudstones analyzed in Gale crater, the diversity in diagenetic processes is primarily captured by the mineralogy and X-ray amorphous chemistry of the drilled rocks. Variations indicate a transition from magnetite to hematite and an increase in matrix-associated sulfates suggesting intensifying influence from oxic, diagenetic fluids upsection. Furthermore, diagenetic fluid pathways are shown to be strongly affected by unconformities and sedimentary transitions, as evidenced by the intensity of alteration inferred from the mineralogy of sediments sampled adjacent to stratigraphic contacts.

Insertion of six different supraglottic airway devices whilst wearing chemical, biological, radiation, nuclear-personal protective equipment: a manikin study.

Six different supraglottic airway devices: Combitube™, laryngeal mask airway, intubating laryngeal mask airway (Fastrach™), i-gel™, Laryngeal Tube™ and Pro-Seal™ laryngeal mask airway were assessed by 58 paramedic students for speed and ease of insertion in a manikin, whilst wearing either chemical, biological, radiation, nuclear-personal protective equipment (CBRN-PPE) or a standard uniform. All devices took significantly longer to insert when wearing CBRN-PPE compared with standard uniform (p < 0.001). In standard uniform, insertion time was shorter than 45 s in 90% of attempts for all devices except the Combitube, for which 90% of attempts were completed by 53 s. Whilst wearing CBRN-PPE the i-gel was the fastest device to insert with a mean (SD (95% CI)) insertion time of 19 (8 (17-21))s, p < 0.001, with the Combitube the slowest with mean (65 (23 (59-71))s. Wearing of CBRN-PPE has a negative impact on supraglottic airway insertion time.

Extubation force: a comparison of adhesive tape, non-adhesive tape and a commercial endotracheal tube holder.

STUDY OBJECTIVE: This study compares adhesive tape, non-adhesive tape and a commercial endotracheal tube holder in terms of the force required to extubate endotracheal tubes from a cadaver. METHODS: A newly deceased, unembalmed cadaver was orotracheally intubated. Senior paramedic students secured the endotracheal tube using adhesive tape applied using the Lillehei method, non-adhesive tape and the Thomas Tube Holder in a random order. The time taken to secure the endotracheal tube and the force required to remove the distal tip of the endotracheal tube from the glottis were recorded. RESULTS: Use of adhesive tape using the Lillehei method resulted in greatest resistance to tube dislodgement, although it took significantly longer to apply than the other two methods. CONCLUSION: Although the Lillehei method provided the greatest resistance to tube dislodgement, it may not be ideal for the prehospital or emergency department context. The Thomas Tube Holder was quick and effective and may provide a good compromise in these environments, although once time is no longer important, clinicians may elect to revert to the Lillehei method which provides greater security.

Does prehospital thrombolysis increase the proportion of patients who have an aborted myocardial infarction?

BACKGROUND: An "aborted" myocardial infarction is defined as an acute coronary syndrome where there is rapid resolution of existing ST segment elevation associated with a rise in creatine kinase (CK) less than twice the upper limit of normal or a small troponin release compatible with minimal myocyte necrosis. Previous research has shown that earlier thrombolysis is associated with a higher rate of aborted infarction. It is also known that prehospital thrombolysis reduces the pain-to-needle time. AIM: To test the hypothesis that prehospital thrombolysis is associated with a higher incidence of aborted infarction in a UK setting. METHODS: A retrospective analysis was performed for all patients given prehospital thrombolysis in the Avon sector catchment area of the Great Western Ambulance Service and Frimley Park Hospital between April 2004 and October 2006. The control group were patients given in-hospital thrombolysis at Frenchay Hospital or Frimley Park Hospital over the same period. Data reporting 12 h troponin levels, call-to-needle time, pain-to-needle time, door-to-needle time and incidence of aborted infarction were collected. RESULTS: Of the patients receiving prehospital thrombolysis, 69% had a pain-to-needle time of 2 h or less compared with 40.4% of patients receiving in-hospital thrombolysis (p<0.001). The overall incidence of aborted infarction was 16.5%. Of those with aborted infarction for whom pain-to-needle times were available, 54% had a pain-to-needle time of <2 h. Despite the difference in pain-to-needle times in favour of prehospital thrombolysis, there was no difference in the incidence of aborted myocardial infarction between the prehospital thrombolysis cohort and the in-hospital cohort, with 18.2% of in-hospital patients having a troponin I level <0.5 ng/ml compared with 11.8% of the prehospital cohort (p = 0.124). CONCLUSION: Although prehospital thrombolysis improved pain-to-needle time and a shorter pain-to-needle time increased the incidence of aborted infarction, prehospital thrombolysis was not associated with an increase in the proportion of aborted myocardial infarctions. Further work is required to understand this unexpected finding.

Is there still a place for emergency department thrombolysis following the introduction of the amended Joint Royal Colleges Ambulance Liaison Committee criteria for thrombolysis?

OBJECTIVE: To apply the current (2004) and the amended (2006) Joint Royal Colleges Ambulance Liaison Committee (JRCALC) criteria for paramedic initiated thrombolysis to all patients who received thrombolytic treatment in an emergency department (ED) to determine if the amendments increase the proportion suitable for paramedic initiated thrombolysis. DESIGN: Retrospective descriptive analysis. METHOD: The ED clinical notes, ambulance clinical record and the first recorded ECG (ED or ambulance) of all patients thrombolysed in the ED during a 12 month period were reviewed against the previous JRCALC guidelines (2004) and the amended JRCALC guidelines (2006) for thrombolysis. RESULTS: Using the JRCALC guidelines (2004), 26 of the 147 patients (17.7%) were eligible for paramedic initiated thrombolysis. Using the JRCALC guidelines (2006), this increased to 41 (27.9%). This difference was statistically significant (McNemar's I2 test with 1 degree of freedom = 15.00; p<0.001). The change to the blood pressure, age and pulse rate parameters has increased the percentage eligible for paramedic initiated thrombolysis by 10.2% (95% confidence interval 4.6% to 15.8%). CONCLUSION: The amended JRCALC guidelines (2006) for paramedic initiated thrombolysis have successfully increased the proportion of patients suitable for prehospital thrombolysis by approximately 10%, although the ED retains an important role in the provision of prompt thrombolytic treatment for a proportion of patients.

Patient safety culture assessment in the nursing home.

OBJECTIVE: To assess patient safety culture (PSC) in the nursing home setting, to determine whether nursing home professionals differ in their PSC ratings, and to compare PSC scores of nursing homes with those of hospitals. METHODS: The Hospital Survey on Patient Safety Culture was modified for use in nursing homes (PSC-NH) and distributed to 151 professionals in four non-profit nursing homes. Mean scores on each PSC-NH dimension were compared across professions (doctors, pharmacists, advanced practitioners and nurses) and with published benchmark scores from 21 hospitals. RESULTS: Response rates were 68.9% overall and 52-100% for different professions. Most respondents (76%) were women and had worked in nursing homes for an average of 9.8 years, and at their current facility for 5.4 years. Professions agreed on 11 of 12 dimensions of the survey and differed significantly (p<0.05) only in ratings for one PSC dimension (attitudes about staffing issues), where nurses and pharmacists believed that they had enough employees to handle the workload. Nursing homes scored significantly lower (ie, worse) than hospitals (p<0.05) in five PSC dimensions (non-punitive response to error, teamwork within units, communication openness, feedback and communication about error, and organisational learning). CONCLUSIONS: Professionals in nursing homes generally agree about safety characteristics of their facilities, and the PSC in nursing homes is significantly lower than that in hospitals. PSC assessment may be helpful in fostering comparisons across nursing home settings and professions, and identifying targets for interventions to improve patient safety.

A culture of patient safety in nursing homes.

BACKGROUND: Few accounts of patient safety initiatives in nursing homes exist. OBJECTIVE: To (1) determine safety culture scores for nursing homes and (2) compare these results with existing data from hospitals. METHODS: Data were collected from a nationally representative sample of nursing homes (n = 2840 completed surveys and a response rate of 71%). From these nursing homes, administrators completed The Hospital Survey On Patient Safety Culture (HSOPSC) instrument. RESULTS: 11 of the 12 HSOPSC subscale scores from the nursing home sample were considerably lower than the benchmark hospital scores. In addition, almost all item scores from nursing homes were considerably lower than the benchmark hospital scores. These results indicate that a less well-developed safety culture exists in nursing homes. CONCLUSIONS: The results clearly show that the patient safety culture scores of nursing homes are considerably lower than those of hospitals. Residents of nursing homes may be at risk of harm as a result of patient safety errors.

What percentages of patients are suitable for prehospital thrombolysis?

OBJECTIVE: To apply the Joint Royal College Ambulance Liaison Committee (JRCALC) checklist to patients who were deemed eligible for thrombolytic therapy on arrival in an Accident & Emergency Department (A&E) to determine the proportion suitable for prehospital thrombolysis. DESIGN: Retrospective descriptive analysis. METHODS: The clinical notes of all patients thrombolysed in an A&E department in a year were reviewed against the JRCALC guidelines for prehospital thrombolysis. RESULTS: 14.2% of patients eligible for thrombolysis in a district general hospital were deemed suitable for prehospital thrombolysis according to the JRCALC criteria. The most common exclusion criteria were hyper/hypotension (50%), onset of symptoms (pain) >6 h previously (41.7%), or age >75 years (37%). Two or more contraindications to prehospital thrombolysis were present in 63.9% of patients. CONCLUSION: The JRCALC guidelines are an effective tool for identifying patients with potential contraindications to thrombolysis.

Maurotoxin: a potent inhibitor of intermediate conductance Ca2+-activated potassium channels.

Maurotoxin, a 34-amino acid toxin from Scorpio maurus scorpion venom, was examined for its ability to inhibit cloned human SK (SK1, SK2, and SK3), IK1, and Slo1 calcium-activated potassium (K(Ca)) channels. Maurotoxin was found to produce a potent inhibition of Ca(2+)-activated (86)Rb efflux (IC(50), 1.4 nM) and inwardly rectifying potassium currents (IC(50), 1 nM) in CHO cells stably expressing IK1. In contrast, maurotoxin produced no inhibition of SK1, SK2, and SK3 small-conductance or Slo1 large-conductance K(Ca) channels at up to 1 microM in physiologically relevant ionic strength buffers. Maurotoxin did inhibit (86)Rb efflux (IC(50), 45 nM) through, and (125)I-apamin binding (K(i), 10 nM) to SK channels in low ionic strength buffers (i.e., 18 mM sodium, 250 mM sucrose), which is consistent with previous reports of inhibition of apamin binding to brain synaptosomes. Under similar low ionic strength conditions, the potency for maurotoxin inhibition of IK1 increased by approximately 100-fold (IC(50), 14 pM). In agreement with its ability to inhibit recombinant IK1 potassium channels, maurotoxin was found to potently inhibit the Gardos channel in human red blood cells and to inhibit the K(Ca) in activated human T lymphocytes without affecting the voltage-gated potassium current encoded by Kv1.3. Maurotoxin also did not inhibit Kv1.1 potassium channels but potently blocked Kv1.2 (IC(50), 0.1 nM). Mutation analysis indicates that similar amino acid residues contribute to the blocking activity of both IK1 and Kv1.2. The results from this study show that maurotoxin is a potent inhibitor of the IK1 subclass of K(Ca) potassium channels and may serve as a useful tool for further defining the physiological role of this channel subtype.

Should ward nurses be using automatic external defibrillators as first responders to improve the outcome from cardiac arrest? A systematic review of the primary research.

INTRODUCTION: The outcome from in-hospital cardiac arrest has improved little since the implementation of cardiopulmonary resuscitation 40 years ago. Early defibrillation improves survival following ventricular fibrillation and pulseless ventricular tachycardia. The emergence of automatic external defibrillators and advisory defibrillators has been heralded as the answer to defibrillation delays in-hospital. AIM: To locate and evaluate the evidence supporting automatic external defibrillator use in-hospital on general wards. METHOD: A systematic review of indexed and grey literature to identify primary research. RESULTS: Fifteen in-hospital automatic external defibrillator studies were located, five met the inclusion criteria. CONCLUSIONS: There is limited primary research evaluating automatic external defibrillators in-hospital. Manual defibrillators remain the most commonly used device for in-hospital defibrillation. Automated external defibrillators offer an alternative to manual defibrillation providing they have a screen and manual override capability, and the technology for pacing is close to hand. For in-hospital automatic external defibrillator programmes to be effective a change in nursing philosophy must occur, and defibrillation must become an expected rather than an extended nursing role.

Administrator turnover and quality of care in nursing homes.

PURPOSE OF THE STUDY: In this article, I examine the association between turnover of nursing home administrators and five important quality of care outcomes. DESIGN AND METHODS: The data came from a survey of 420 nursing facilities and the 1999 On-line Survey, Certification, and Reporting System. Using multivariate logistic regression analyses, I looked at the effects of turnover of administrators in nursing homes belonging to chain organizations and in nursing homes not belonging to chain organizations. RESULTS: I found the average annual turnover rate of administrators to be 43%. The multivariate logistic regression analyses show that in nursing homes belonging to chains, administrator turnover is associated with a higher than average proportion of residents who were catheterized, had pressure ulcers, and were given psychoactive drugs and with a higher than average number of quality-of-care deficiencies. In nursing homes not belonging to chains I found that turnover of administrators is associated with a higher than average proportion of residents who were restrained, were catheterized, had pressure ulcers, and were given psychoactive drugs. IMPLICATIONS: There is a need to improve understanding of how and why better outcomes are achieved in some nursing homes. This investigation serves to focus attention on nursing home administrators. I believe this study provides preliminary evidence that the turnover of administrators may have an important association with quality of care in nursing homes.

Relocation of the elderly.

In this article, the author reviews 78 studies addressing the relocation of the elderly. He begins by defining the four major forms of relocation and describing the trends in the current health care marketplace precipitating relocation events. Next, he reviews the major findings of studies assessing the potential negative and positive outcomes of relocation. These outcomes include changes in mortality rates, morbidity, and psychological or social changes. In addition, factors associated with successful relocation are presented. Finally, the primary contribution of this article is that the author assesses the strengths and limitations of this prior literature and combines the research he reviews in an analytic model. This model helps show some opportunities for future research in the relocation of the elderly.

Innovation in nursing homes: which facilities are the early adopters?

PURPOSE: This study examined organizational and market factors associated with nursing homes that are most likely to be early adopters of innovations. Early adopter institutions, defined as the first 20% of facilities to adopt an innovation, are important because they subsequently facilitate the diffusion of innovations to others in the industry. DESIGN AND METHODS: Two groups of innovations were examined, special care units and subacute care services. I used discrete-time logistic regression analysis and nationally representative data from 13,162 facilities at risk of being early adopters of innovations during twelve 6-month intervals from 1992 to 1997. RESULTS: Organizational factors that increase the likelihood of early innovation adoption are larger bed size, chain membership, and high levels of private-pay residents. Four market factors that increase the likelihood of early innovation adoption are: a retrospective Medicaid reimbursement methodology, a more competitive environment, higher average income in the county, and a higher number of hospital beds in the county. IMPLICATIONS: This analysis shows that organizational and market characteristics of nursing homes affect their propensity toward early adoption of innovations. Some of the results may be useful for nursing home administrators and policy makers attempting to promote innovation.

Citations and compliance with the Nursing Home Reform Act of 1987.

The purpose of this article is to show which Nursing Home Reform Act (NHRA) regulations nursing homes are, and are not, complying with. This is achieved by using deficiency citations that are issued by state and federal inspectors when a facility does not meet a NHRA standard. Structural and process characteristics of nursing homes associated with these deficiency citations are presented. The results of these analyses are discussed in terms of their policy issues.

Deficiency citations for mental health care in nursing homes.

The Centers for Medicare and Medicaid Services (CMS) certifies approximately 17,000 nursing homes per year. When a facility does not meet a standard, a deficiency citation is issued. Using 1998 citations, we examined the structure and process characteristics of nursing homes that were associated with mental health deficiencies. Our findings showed that (a) some nursing homes have a high number of deficiencies in the area of mental health care; (b) these deficiencies do not appear to be associated with specific processes used in nursing homes; and (c) some structural factors such as staffing, private-pay occupancy, and Medicare occupancy appear to have an important influence on the number of mental health care deficiencies.