Spectral reflectance characteristics of soils in northeastern Brazil as influenced by salinity levels.

In northeastern Brazil, large swaths of once-productive soils have been severely degraded by soil salinization, but the true extent of the damage has not been assessed. Emerging remote sensing technology based on hyperspectral analysis offers one possibility for large-scale assessment, but it has been unclear to what extent the spectral properties of soils are related to salinity characteristics. The purpose of this study was to characterize the spectral properties of degraded (saline) and non-degraded agricultural soils in northeastern Brazil and determine the extent to which these properties correspond to soil salinity. We took soil samples from 78 locations within a 45,000-km2 site in Pernambuco State. We used cluster analysis to group the soil samples on the basis of similarities in salinity and sodicity levels, and then obtained spectral data for each group. The physical properties analysis indicated a predominance of the coarse sand fraction in almost all the soil groups, and total porosity was similar for all the groups. The chemical analysis revealed different levels of degradation among the groups, ranging from non-degraded to strongly degraded conditions, as defined by the degree of salinity and sodicity. The soil properties showing the highest correlation with spectral reflectance were the exchangeable sodium percentage followed by fine sand. Differences in the reflectance curves for the various soil groups were relatively small and were not significant. These results suggest that, where soil crusts are not present, significant challenges remain for using hyperspectral remote sensing to assess soil salinity in northeastern Brazil.

What influences safety in paramedicine? Understanding the impact of stress and fatigue on safety outcomes.

OBJECTIVE: The purpose of this study was to build on extant research linking fatigue to safety outcomes in paramedicine by assessing the influence of a multiplicity of workplace stressors, including chronic and critical incident stresses on safety outcomes. METHODS: A cross-sectional survey was deployed to 10 paramedic services in Ontario. Validated survey instruments measured operational and organizational chronic stress, critical incident stress, post-traumatic stress symptomatology (PTSS), fatigue, safety outcomes, and demographics. Analysis of covariance assessed associations of workplace stresses with safety outcomes and corroborated findings using hierarchical linear model and generalized estimating equations (GEE) by taking into account paramedic service when assessing the proposed associations. A non-responder survey was conducted to asses for demographic differences in those who did and did not complete the survey. RESULTS: This survey had a response rate of 40.5% (n = 717/1767); 80% of paramedics reported an injury or exposure to pathogen, 95% reported safety compromising behaviors, and 76% reported medical errors. In the GEE analyses, paramedic injury was significantly related to fatigue (0.13, SE = 0.06, P = 0.020), critical incident stress (0.03, SE = 0.01, P < 0.01), and PTSS (0.03, SE = 0.01, P < 0.01). Safety compromising behaviors were significantly associated with fatigue (0.37, SE = 0.06, P < 0.01), organizational stress (0.06, SE = 0.01, P < 0.01), and critical incident stress (0.01. SE = 0.01, P = 0.017). Medication errors were significantly related to fatigue (0.12, SE = 0.05, P < 0.01). Finally, the bivariate analysis showed increased stress factors and fatigue was associated with increased safety outcomes. CONCLUSION: These findings illustrate that a host of different stressors may influence safety-related behaviors. For those interested in safety, these findings point to the need for a holistic focus on fatigue and stress in paramedicine.

The out-of-hospital validation of the Canadian C-Spine Rule by paramedics.

STUDY OBJECTIVE: We designed the Canadian C-Spine Rule for the clinical clearance of the cervical spine, without need for diagnostic imaging, in alert and stable trauma patients. Emergency physicians previously validated the Canadian C-Spine Rule in 8,283 patients. This study prospectively evaluates the performance characteristics, reliability, and clinical sensibility of the Canadian C-Spine Rule when used by paramedics in the out-of-hospital setting. METHODS: We conducted this prospective cohort study in 7 Canadian regions and involved alert (Glasgow Coma Scale score 15) and stable adult trauma patients at risk for neck injury. Advanced and basic care paramedics interpreted the Canadian C-Spine Rule status for all patients, who then underwent immobilization and assessment in the emergency department to determine the outcome, clinically important cervical spine injury. RESULTS: The 1,949 patients enrolled had these characteristics: median age 39.0 years (interquartile range 26 to 52 years), female patients 50.8%, motor vehicle crash 62.5%, fall 19.9%, admitted to the hospital 10.8%, clinically important cervical spine injury 0.6%, unimportant injury 0.3%, and internal fixation 0.3%. The paramedics classified patients for 12 important injuries with sensitivity 100% (95% confidence interval [CI] 74% to 100%) and specificity 37.7% (95% CI 36% to 40%). The kappa value for paramedic interpretation of the Canadian C-Spine Rule (n=155) was 0.93 (95% CI 0.87 to 0.99). Paramedics conservatively misinterpreted the rule in 320 (16.4%) patients and were comfortable applying the rule in 1,594 (81.7%). Seven hundred thirty-one (37.7%) out-of-hospital immobilizations could have been avoided with the Canadian C-Spine Rule. CONCLUSION: This study found that paramedics can apply the Canadian C-Spine Rule reliably, without missing any important cervical spine injuries. The adoption of the Canadian C-Spine Rule by paramedics could significantly reduce the number of out-of-hospital cervical spine immobilizations.

Fatigue and Safety in Paramedicine.

OBJECTIVES: Extant research has established an empirical relationship between fatigue and safety-related outcomes. It is not clear if these findings are relevant to Canadian paramedicine. The purpose of this study was to determine if fatigue and shiftwork variables were related to safety outcomes in Canadian paramedics. METHODS: A survey was conducted with ten paramedic services in Ontario with a 40.5% response rate (n = 717). Respondents reported levels of fatigue, safety outcomes (injury, safety compromising behaviours, and medical errors/adverse events), work patterns (types of shifts, hours worked weekly) and demographic characteristics. Univariate and logistic regression analyses were used to assess for significant differences. RESULTS: In this sample, 55% of paramedics reported being fatigued at work. Fatigued paramedics were over twice as likely to report injuries, three times as likely to report safety compromising behaviors, and 1.5 times more likely to report errors/adverse outcomes. When controlling for fatigue, shift length variables did not consistently influence safety outcomes. CONCLUSION: These results create preliminary evidence of a relationship between fatigue and safety outcomes in Canadian paramedicine. While more research is needed, these findings point to the influence fatigue has on safety outcomes and provide an indication that fatigue mitigation efforts may be worthwhile.

OBJECTIF: D'après les travaux de recherche, il existe une relation empirique entre la fatigue et les résultats liés à la sécurité. Toutefois, on ne sait pas si les constatations s'appliquent à la paramédecine au Canada. L'étude avait donc pour but de déterminer si la fatigue et les variables relatives au travail par postes avaient une incidence sur les résultats liés à la sécurité chez les ambulanciers paramédicaux au Canada. MÉTHODE: Une enquête a été menée dans 10 services paramédicaux, en Ontario, et le taux de réponse a atteint 40,5% (n = 717). Les participants devaient faire état du degré de fatigue, de résultats liés à la sécurité (blessure, comportements mettant en péril la sécurité, erreurs médicales et effets indésirables), du régime de travail (type de roulement, nombre d'heures de travail par semaine) et de données démographiques. Des analyses de régression logistique et unidimensionnelle ont été effectuées afin de mettre en évidence des écarts importants. RÉSULTATS: Dans l'échantillon étudié, 55% des ambulanciers paramédicaux ont déclaré ressentir de la fatigue au travail. Ceux-ci étaient plus de deux fois susceptibles de subir des blessures, trois fois plus susceptibles d'avoir des comportements mettant en péril la sécurité et une fois et demie plus susceptibles de déclarer des erreurs ou des effets indésirables. Par ailleurs, lorsqu'on tenait compte de la fatigue, les variables relatives à la durée des postes de travail n'avaient pas la même incidence sur les résultats liés à la sécurité. CONCLUSION: Les résultats fournissent des données préliminaires sur l'existence d'une relation entre la fatigue et les résultats liés à la sécurité en paramédecine au Canada. Si le sujet demande à être approfondi, les constations font déjà ressortir l'incidence de la fatigue sur les résultats liés à la sécurité ainsi que la pertinence de trouver des moyens d'atténuation de la fatigue.

BIPHASIC Trial: a randomized comparison of fixed lower versus escalating higher energy levels for defibrillation in out-of-hospital cardiac arrest.

BACKGROUND: There is little clear evidence as to the optimal energy levels for initial and subsequent shocks in biphasic waveform defibrillation. The present study compared fixed lower- and escalating higher-energy regimens for out-of-hospital cardiac arrest. METHODS AND RESULTS: The Randomized Controlled Trial to Compare Fixed Versus Escalating Energy Regimens for Biphasic Waveform Defibrillation (BIPHASIC Trial) was a multicenter, randomized controlled trial of 221 out-of-hospital cardiac arrest patients who received > or = 1 shock given by biphasic automated external defibrillator devices that were randomly programmed to provide, blindly, fixed lower-energy (150-150-150 J) or escalating higher-energy (200-300-360 J) regimens. Patient mean age was 66.0 years; 79.6% were male. The cardiac arrest was witnessed in 63.8%; a bystander performed cardiopulmonary resuscitation in 23.5%; and initial rhythm was ventricular fibrillation/ventricular tachycardia in 92.3%. The fixed lower- and escalating higher-energy regimen cases were similar for the 106 multishock patients and for all 221 patients. In the primary analysis in multishock patients, conversion rates differed significantly (fixed lower, 24.7%, versus escalating higher, 36.6%; P=0.035; absolute difference, 11.9%; 95% CI, 1.2 to 24.4). Ventricular fibrillation termination rates also were significantly different between groups (71.2% versus 82.5%; P=0.027; absolute difference, 11.3%; 95% CI, 1.6 to 20.9). For the secondary analysis of first shock success, conversion rates were similar between the fixed lower and escalating higher study groups (38.4% versus 36.7%; P=0.92), as were ventricular fibrillation termination rates (86.8% versus 88.8%; P=0.81). There were no distinguishable differences between regimens for survival outcomes or adverse effects. CONCLUSIONS: This is the first randomized trial to compare fixed lower and escalating higher biphasic energy regimens in out-of-hospital cardiac arrest, and it demonstrated higher rates of ventricular fibrillation conversion and termination with an escalating higher-energy regimen for patients requiring multiple shocks. These results suggest that patients in ventricular fibrillation benefit from higher biphasic energy levels if multiple defibrillation shocks are required.

Investigational Overview of Supervised Clinical Practice Experiences.

PURPOSE: While the Accreditation Review Commission on Education for the Physician Assistant (ARC-PA) provides standards, there is variation allowed in design and implementation of supervised clinical practice experiences (SCPEs). Limited research has assessed for a correlation between SCPE design and program outcomes, including PANCE "First-Time Taker Pass Rate." The objective of this research is to evaluate for trends and best practices in clinical education design, as well as any correlation to PANCE pass rate. METHODS: Data were gathered through an online survey with 14 multiple-choice questions referring to "core" clinical rotations and then anonymously tabulated. Participants were identified by ARC-PA's listing of PA programs as of May 2014, excluding those programs with "Accreditation-Provisional" or "Accreditation-Probation" statuses. Contact was initiated with one faculty member at each program. A post hoc analysis was performed to evaluate for correlations between SCPE design and PANCE pass rates. RESULTS: Our research quantifies variation in many aspects of the administration and design of the clinical education curriculum. During post hoc analysis, the groups were divided into "above average" and "average or below" in relation to PANCE pass rates compared with the national average, with several significant differences identified. These differences include the average length of rotation, programs that require a minimum end-of-rotation passing score, and programs that require a minimum score on the preceptor evaluation. CONCLUSIONS: This research demonstrated many viable options and approaches to various components of clinical education, as well as some correlations between supervised clinical practice experience (SCPE) design and PANCE first-time taker pass rates.

Predictors of posttraumatic stress and preferred sources of social support among Canadian paramedics.

OBJECTIVE: Emergency medical service (EMS) providers are exposed to a variety of stressors endemic to the profession. These exposures may contribute to stress reactions, including posttraumatic stress. The objective of this study was to evaluate the relationship between work-related stressors and posttraumatic stress. The secondary objective was to determine paramedics' preferred sources of support for managing work-related stress. METHODS: 269 paramedics in a county-based EMS service were invited to complete an online survey. Respondents reported their demographic characteristics, levels of chronic stress, critical incident stress, posttraumatic stress symptomatology (PTSS), and preferred sources of support for managing work-related stress. RESULTS: A total of 145 paramedics completed the survey. PTSS was significantly correlated with operational stress (p<0.001), organizational stress (p<0.001), and critical incident stress (p<0.001). Regression models revealed that chronic operational stress was a significant independent predictor of PTSS (p<0.001) and in combination with critical incident stress (p<0.01). Paramedics reported a higher preference for receiving support from a work partner, friend, or family member than from other sources (p<0.001). CONCLUSION: Both chronic and critical incident stressors appear to be significant predictors of PTSS. Our findings suggests that holistic health and wellness initiatives that address the impact of both critical incident stress and the chronic stressors associated with day-to-day operations may help mitigate PTSS. Our findings also provide preliminary evidence that interventions may benefit from a focus on peer support and on friends and family members who can support the affected paramedic.