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Fluid flow through fractured media is typically governed by the distribution of fracture apertures, which are in turn governed by stress. Consequently, understanding subsurface stress is critical for understanding and predicting subsurface fluid flow. Although laboratory‐scale studies have established a sensitive relationship between effective stress and bulk electrical conductivity in crystalline rock, that relationship has not been extensively leveraged to monitor stress evolution at the field scale using electrical or electromagnetic geophysical monitoring approaches. In this paper we demonstrate the use time‐lapse 3‐dimensional (4D) electrical resistivity tomography to image perturbations in the stress field generated by pressurized borehole packers deployed during shear‐stimulation attempts in a 1.25 km deep metamorphic crystalline rock formation. Plain Language Summary: Time‐lapse electrical geophysical sensing is used to image 3D changes in rock stress generated by an isolated and pressurized interval of a borehole in a deep, dense, fractured rock formation. Key Points: Remotely monitoring stress is challenging but important for relating geomechanical behavior to flow pathways during energy productionBulk electrical conductivity is sensitive to stress in crystalline rockTime‐lapse electrical resistivity tomography can be used to remotely monitor 3D changes in effective stress [ABSTRACT FROM AUTHOR]

Fluid flow through fractured rock systems is governed in large part by the distribution, interconnectivity, and size of fracture apertures. In‐situ stress is one of the primary factors controlling fracture aperture, and one that is altered significantly during high‐pressure fluid injections or extractions. Interactions between stress, pore pressure, aperture, and fluid flow can result in complex and evolving poroelastic behavior with significant implications regarding the predictability and risk involved with developing and managing deep subsurface reservoirs (geothermal, fossil energy, and geologic carbon sequestration). In saturated rocks, bulk electrical conductivity is sensitive to both primary and secondary porosity (i.e., matrix porosity and fractures), and therefore to fracture aperture size and distribution. We demonstrate the use of time‐lapse 3D electrical resistivity tomography for remotely monitoring stress induced changes in aperture distribution during high pressure injections into a dense fractured rock system at a scale of tens of meters. Results reveal a complex and continuously evolving stress field involving aperture dilations in the natural fracture system and aperture contractions in adjacent zones of shadow stress. Results provide information about the spatiotemporal changes in the system behavior and point to the potential of electrical imaging for autonomously and remotely monitoring evolving stress conditions by proxy through changes in bulk electrical conductivity. Plain Language Summary: The state and evolution of the stress exerted on rocks has a governing influence on how fluids migrate through deep, fractured rock systems. Dynamic changes in stress during subsurface fluid injections and extractions are difficult to observe, which limits the ability to optimize the management of subsurface reservoirs. We demonstrate how time‐lapse 3D (i.e., 4D) electrical geophysical imaging can be used to monitor how fractures expand and contract in response to stresses induced during high‐pressure injections into a deep fractured rock formation. Results point to the potential of autonomous electrical imaging for providing actionable feedback information during reservoir operations, enabling enhanced understanding and control. Key Points: Time‐Lapse 3D ERT imaging is used to monitor stress‐induced fracture dilation and contraction during high pressure injectionsHigh temporal resolution reveals fine details of complex dynamic poroelastic system behavior during and after high pressure injectionsResults demonstrate the potential of ERT for remote, proxy monitoring of changes in stress and fracture aperture in fractured‐rock systems [ABSTRACT FROM AUTHOR]

Widespread permafrost thaw in response to changing climate conditions has the potential to dramatically impact ecosystems, infrastructure, and the global carbon budget. Ambient seismic noise techniques allow passive subsurface monitoring that could provide new insights into permafrost vulnerability and active‐layer processes. Using nearly 2 years of continuous seismic data recorded near Fairbanks, Alaska, we measured relative velocity variations that showed a clear seasonal cycle reflecting active‐layer freeze and thaw. Relative to January 2014, velocities increased up to 3% through late spring, decreased to −8% by late August, and then gradually returned to the initial values by the following winter. Velocities responded rapidly (over ~2 to 7 days) to discrete hydrologic events and temperature forcing and indicated that spring snowmelt and infiltration events from summer rainfall were particularly influential in propagating thaw across the site. Velocity increases during the fall zero‐curtain captured the refreezing process and incremental ice formation. Looking across multiple frequency bands (3–30 Hz), negative relative velocities began at higher frequencies earlier in the summer and then shifted lower when active‐layer thaw deepened, suggesting a potential relationship between frequency and thaw depth; however, this response was dependent on interstation distance. Bayesian tomography returned 2‐D time‐lapse images identifying zones of greatest velocity reduction concentrated in the western side of the array, providing insight into the spatial variability of thaw progression, soil moisture, and drainage. This study demonstrates the potential of passive seismic monitoring as a new tool for studying site‐scale active‐layer and permafrost thaw processes at high temporal and spatial resolution. Plain Language Summary: Seismic vibrations in the ground generated by background sources of noise (vehicle traffic, wind, ocean waves, etc.) occur continuously and provide a way to monitor environmental changes with time. We used 2 years of noise data to study belowground changes in Alaska, where the upper layer of soil freezes and thaws seasonally and deeper soil (permafrost) remains frozen year‐round. Warming temperatures may alter the depth of thaw each summer and degrade permafrost, which could significantly impact ecosystems and infrastructure. Our results show a clear seasonal pattern corresponding with the timing of soil freeze/thaw. Vibrations traveled at the fastest speeds during early spring, indicating frozen soil with ice. Speeds became slower following snowmelt and warmer temperatures in late spring and early summer. Strong decreases in seismic‐wave speeds corresponded with heavy rains and warm temperatures, suggesting warm water percolating downward through the soil induced more thaw. Speeds gradually increased again through the fall during ice formation. We also mapped where soil changes occurred most strongly and thereby revealed spatial differences in thaw depth and soil moisture across the site. This work demonstrates that seismic noise measurements can be a valuable new tool for monitoring and mapping belowground changes in cold regions. Key Points: Seismic velocity trends reveal a clear seasonal cycle with short timescale changes highlighting the importance of infiltration eventsVelocity increases during the zero‐curtain time period provide a unique look into the freezing process and ice formation ratesPassive seismic monitoring shows great potential for spatiotemporal monitoring of subsurface dynamics in permafrost environments [ABSTRACT FROM AUTHOR]

Abstract: We analyze near‐repeating broadband seismograms from nearly 3,000 eruptions (2003–2011) from the Erebus volcano lava lake to investigate temporal changes in the shallow eruptive dynamics of an open conduit volcano. Cross‐correlation analysis reveals progressive variable time lags between correlation‐aligned short period (SP) and very long period (VLP) seismogram components ranging over approximately ±1 s and evolving over weeks to months. Lava lake eruptions both excite an SP explosion seismic signal and gravitationally unload the conduit. After a delay of several seconds, this unloading excites a posteruptive, minute‐long VLP seismic signal that persist for several minutes until the lava lake is refilled. VLP‐SP lag variations are consistent across multiple seismic stations and are independent of eruption size, spectral characteristics, eruption frequency, and lava lake morphology changes. Lag changes are interpreted in terms of variable communication time between eruptions and the subsequent elastic and gravitational response of a tomographically imaged near‐summit magma storage and VLP source region several hundred meters below the lava lake. Tomographic and VLP moment tensor studies, combined with modeling, suggest that the elastodynamic communication time between the distinct SP and VLP source regions is mediated by conduit‐guided Stoneley waves within the uppermost magma‐filled conduit system that are sensitive to small shallow conduit geometry changes. Conduit geometry changes may be driven by internal or external processes, including conduit wall melting and refreezing, repeated eruptive slug erosion, and deformation from inner crater inflation or collapse. [ABSTRACT FROM AUTHOR]

Objectives To compared outcomes of regional nerve blocks with those of standard analgesics after hip fracture. Design Multisite randomized controlled trial from April 2009 to March 2013. Setting Three New York hospitals. Participants Individuals with hip fracture (N = 161). Intervention Participants were randomized to receive an ultrasound-guided, single-injection, femoral nerve block administered by emergency physicians at emergency department ( ED) admission followed by placement of a continuous fascia iliaca block by anesthesiologists within 24 hours (n = 79) or conventional analgesics (n = 82). Measurements Pain (0-10 scale), distance walked on Postoperative Day ( POD) 3, walking ability 6 weeks after discharge, opioid side effects. Results Pain scores 2 hours after ED presentation favored the intervention group over controls (3.5 vs 5.3, P = .002). Pain scores on POD 3 were significantly better for the intervention than the control group for pain at rest (2.9 vs 3.8, P = .005), with transfers out of bed (4.7 vs 5.9, P = .005), and with walking (4.1 vs 4.8, P = .002). Intervention participants walked significantly further than controls in 2 minutes on POD 3 (170.6 feet, 95% confidence interval ( CI) = 109.3-232 vs 100.0 feet, 95% CI = 65.1-134.9; P = .04). At 6 weeks, intervention participants reported better walking and stair climbing ability (mean Functional Independence Measure locomotion score of 10.3 (95% CI = 9.6-11.0) vs 9.1 (95% CI = 8.2-10.0), P = .04). Intervention participants were significantly less likely to report opioid side effects (3% vs 12.4%, P = .03) and required 33% to 40% fewer parenteral morphine sulfate equivalents. Conclusion Femoral nerve blocks performed by emergency physicians followed by continuous fascia iliaca blocks placed by anesthesiologists are feasible and result in superior outcomes. [ABSTRACT FROM AUTHOR]

Background: The frequency of delirium among patients with cancer presenting to the emergency department (ED) is unknown. The purpose of this study was to determine delirium frequency and recognition by ED physicians among patients with advanced cancer presenting to the ED of The University of Texas MD Anderson Cancer Center.Methods: The study population was a random sample of English-speaking patients with advanced cancer who presented to the ED and met the study criteria. All patients were assessed with the Confusion Assessment Method (CAM) to screen for delirium and with the Memorial Delirium Assessment Scale (MDAS) to measure delirium severity (mild, ≤15; moderate, 16-22; and severe, ≥23). ED physicians were also asked whether their patients were delirious.Results: Twenty-two of the 243 enrolled patients (9%) had CAM-positive delirium, and their median MDAS score was 14 (range, 9-21 [30-point scale]). The median age of the enrolled patients was 62 years (range, 19-89 years). Patients with delirium had a poorer performance status than patients without delirium (P < .001); however, the 2 groups did not differ in other characteristics. Ten of the 99 patients who were 65 years old or older (10%) had CAM-positive delirium, whereas 12 of the 144 patients younger than 65 years (8%) did (P = .6). According to the MDAS scores, delirium was mild in 18 patients (82%) and moderate in 4 patients (18%). Physicians correctly identified delirium in 13 of the CAM-positive delirious patients (59%).Conclusions: Delirium is relatively frequent and is underdiagnosed by physicians in patients with advanced cancer who are visiting the ED. Further research is needed to identify the optimal screening tool for delirium in ED. Cancer 2016. © 2016 American Cancer Society. Cancer 2016;122:2918-2924. © 2016 American Cancer Society. [ABSTRACT FROM AUTHOR]

Objectives Patient compliance and satisfaction with analgesics prescribed after emergency department ( ED) care for acute pain are poorly understood, largely because of the lack of direct patient follow-up with the ED provider. Our objective was to compare patient satisfaction with three analgesia regimens prescribed for post- ED care-a nasally administered nonsteroidal anti-inflammatory drug ( NSAID), an opioid, or combination therapy-by collecting granular follow-up on analgesic use, pain scores, side effects, work activity levels, and overall satisfaction directly from patients. Methods We designed a prospective registry linking ED assessment and analgesic management for acute pain of specific musculoskeletal or visceral etiologies with self-reported automated telephonic follow-up daily for the 4 days post- ED discharge. Patients were prescribed a specific NSAID ( SPRIX, ketorolac tromethamine for nasal instillation) only, an oral opioid only, or both with the opioid clearly defined as rescue therapy, at the ED provider's discretion. Results There were 824 evaluable subjects. Maximum pain scores improved day to day more effectively with a ketorolac-based approach. Self-reported rates of return to work and work effectiveness were higher with SPRIX than with opioids or combination therapy. Adverse effects of nausea, constipation, drowsiness, and abdominal pain were higher each day among patients taking an opioid; nasal irritation was more common with SPRIX. Overall satisfaction at the end of the follow-up period was higher with SPRIX-based treatment than with opioid monotherapy. Conclusions Automated telephonic follow-up of ED patients prescribed short-term analgesia is feasible. Ketorolac-based analgesia after an ED visit for many acute pain syndromes was associated with favorable patient outcomes and higher satisfaction than opioid-based therapy. SPRIX, an NSAID that is not available over the counter and has a novel delivery approach, may be useful for short-term post- ED outpatient analgesia. [ABSTRACT FROM AUTHOR]

Objectives One of the most challenging areas of emergency medicine practice is the management and treatment of severe and persistent pain, including cancer-related pain. Emergency departments ( EDs) in the United States frequently provide care for patients with cancer and an increasing concern is the potential for opioid misuse in this patient group. The authors determined the risk for opioid misuse among ED cancer patients with pain and assessed demographic and clinical factors associated with increased misuse risk. The Texas state prescription monitoring program was also queried for evidence of multiple opioid prescriptions for comparing low- and high-risk groups. Methods The Screener and Opioid Assessment for Patients with Pain-Revised ( SOAPP-R) was administered to assess risk for opioid misuse among cancer patients presenting to the ED of a comprehensive cancer center in the United States. Eligibility criteria included: 1) presentation for treatment of chronic cancer-related pain while taking a prescribed schedule II opioid for analgesia, 2) age of 18 years or older, 3) ability to speak English, and 4) ability to understand the study and give written informed consent. Results Of 934 ED patients screened for the study, 290 were eligible and 209 participated (72% response rate). On the basis of the recommended SOAPP-R cutoff score of 18, a total of 71 of the 209 patients (34%) were categorized as having a high risk of misuse. Of note, 15% and 4% of all patients reported past or current use of illicit substances, respectively. The total number of annual opioid prescriptions (17.8 vs. 12.6; p = 0.023) differed between the high- versus low-risk groups. Multivariable analyses showed that depression (odds ratio [ OR] = 3.06, 95% confidence interval [ CI] = 1.45 to 6.48; p = 0.003), poor coping ( OR = 1.08, 95% CI = 1.03 to 1.13; p = 0.001), and illicit substance use ( OR = 28.30, 95% CI = 2.97 to 269.24; p = 0.029) were significantly associated with high risk of opioid misuse. Conclusions The risk of opioid misuse among cancer patients is substantial. Screening for opioid misuse in the ED is feasible. [ABSTRACT FROM AUTHOR]

ACADEMIC EMERGENCY MEDICINE 2010; 17:848–858 © 2010 by the Society for Academic Emergency Medicine Objectives: A decision support tool may guide emergency clinicians in recognizing assessment, analgesic and overall management, and health service delivery needs for patients with sickle cell disease (SCD) in the emergency department (ED). We aimed to identify data and process elements important in making decisions regarding evaluation and management of adult patients in the ED with painful episodes of SCD. Methods: Qualitative methods using a series of focus groups and grounded theory were used. Eligible participants included adult clients with SCD and emergency physicians and nurses with a minimum of 1 year of experience providing care to patients with SCD in the ED. Patients were recruited in conjunction with annual SCD meetings, and providers included clinicians who were and were not affiliated with sickle cell centers. Groups were conducted until saturation was reached and included a total of two patient groups, three physician groups, and two nurse groups. Focus groups were held in New York, Durham, Chicago, New Orleans, and Denver. Clinician participants were asked the following three questions to guide the discussion: 1) what information would be important to know about patients with SCD in the ED setting to effectively care for them and help you identify patient analgesic, treatment, and referral needs? 2) What treatment decisions would you make with this information? and 3) What characteristics would a decision support tool need to have to make it meaningful and useful? Client participants were asked the same questions with rewording to reflect what they believed providers should know to provide the best care and what they should do with the information. All focus groups were audiotaped and transcribed. The constant comparative method was used to analyze the data. Two coders independently coded participant responses and identified focal themes based on the key questions. An investigator and assistant independently reviewed the transcripts and met until the final coding structure was determined. Results: Forty-seven individuals participated (14 persons with SCD, 16 physicians, and 17 nurses) in a total of seven different groups. Two major themes emerged: acute management and health care utilization. Major subthemes included the following: physiologic findings, diagnostics, assessment and treatment of acute painful episodes, and disposition. The most common minor subthemes that emerged included past medical history, presence of a medical home (physician or clinic), individualized analgesic treatment plan for treatment of painful episodes, history of present illness, medical home follow-up available, patient-reported analgesic treatment that works, and availability of analgesic prescription at discharge. Additional important elements in treatment of acute pain episodes included the use of a standard analgesic protocol, need for fluids and nonpharmacologic interventions, and the assessment of typicality of pain presentation. The patients’ interpretation of the need for hospital admission also ranked high. Conclusions: Participants identified several areas that are important in the assessment, management, and disposition decisions that may help guide best practices for SCD patients in the ED setting. [ABSTRACT FROM AUTHOR]

Int J Dent Hygiene 3, 2005; 112–116 Goe LC, Baysac MAS, Todd KH, Linton JA: Assessing the prevalence of dental caries among elementary school children in North Korea: a cross-sectional survey in the Kangwon province The lack of epidemiological studies has made it difficult to assess the extent of public health problems in North Korea. In the absence of empirical data, less intrusive study designs acceptable to the North Korean government could be developed to gauge the public's health. To this end we developed a basic oral health survey in order to assess the prevalence of untreated dental caries among children. A cross-sectional survey of 854 elementary school students was conducted in the city of Wonsan, North Korea. Students were screened and classified into one of three states of oral health: no caries, minor caries or severe dental caries. Verbal surveys were concurrently administered on children to collect basic information on oral health behaviours and demographic characteristics. Statistical analyses were performed to determine if any variables were significant predictors of oral health status category. Among the 854 students screened, we found 255 students with no caries (29.9%), 316 students with minor caries (37.0%), and 283 students with severe caries (33.1%). The majority of students (70.1%) screened had dental caries. Almost all of the students (98.5%) claimed to brush their teeth daily and 71.2% of students visited a dentist in the past year. There were no significant predictors of oral health status. The oral health of children in Wonsan, North Korea is comparable if not slightly better than the oral health status of children of similar age in countries with similar Social-Economic Status (SES) . Basic oral health screens are useful to produce a snapshot of general oral health status among children in North Korea and may provide insight as to the general health of these children. [ABSTRACT FROM AUTHOR]

Patients presenting to the emergency department with heart failure are evaluated based on the subjective sensation of dyspnea. In this study, the authors sought to determine the change in dyspnea, measured by a visual analog scale (VAS), which is associated with a meaningful change in the patient's perception and the effect of dyspnea severity on the VAS. In this prospective, observational study the authors defined a meaningful change in VAS dyspnea as the difference between VAS scores when patients reported "a little less difficulty breathing" or "a little more difficulty breathing." Seventy-four patients were evaluated, and the mean for a meaningful change in VAS was 21.1 mm (95%confidence interval, 12.3 --29.9 mm). Patients that recorded higher index VAS scores had a significantly greater change in VAS. VAS scores and the changes with treatment provide the treating physician with another means to assess the effects of their interventions. [ABSTRACT FROM AUTHOR]

See Commentary, page 271. [ABSTRACT FROM AUTHOR]

The author reflects on emergency medicine and the palliative care movement. He suggests that many patients with chronic life-limiting illnesses receive regular emergency care that wastes resources and fails to address their stage of disease and care. He argues that the emergency department is an ideal setting for identifying the palliative care needs of chronically ill patients and referring them to palliative care services which can ease symptoms and improve the coordination of services.