Characterizing large earthquakes before rupture is complete.

Whether earthquakes of different sizes are distinguishable early in their rupture process is a subject of debate. Studies have shown that the frequency content of radiated seismic energy in the first seconds of earthquakes scales with magnitude, implying determinism. Other studies have shown that recordings of ground displacement from small to moderate-sized earthquakes are indistinguishable, implying a universal early rupture process. Regardless of how earthquakes start, events of different sizes must be distinguishable at some point. If that difference occurs before the rupture duration of the smaller event, this implies some level of determinism. We show through analysis of a database of source time functions and near-source displacement records that, after an initiation phase, ruptures of M7 to M9 earthquakes organize into a slip pulse, the kinematic properties of which scale with magnitude. Hence, early in the rupture process-after about 10 s-large and very large earthquakes can be distinguished.

Slab2, a comprehensive subduction zone geometry model.

Subduction zones are home to the most seismically active faults on the planet. The shallow megathrust interfaces of subduction zones host Earth's largest earthquakes and are likely the only faults capable of magnitude 9+ ruptures. Despite these facts, our knowledge of subduction zone geometry-which likely plays a key role in determining the spatial extent and ultimately the size of subduction zone earthquakes-is incomplete. We calculated the three-dimensional geometries of all seismically active global subduction zones. The resulting model, called Slab2, provides a uniform geometrical analysis of all currently subducting slabs.

Teaching Incision and Drainage: Perceived Educational Value of Abscess Models.

OBJECTIVES: Incision and drainage (I&D) of skin abscesses is an important procedural skill for pediatric emergency medicine providers. Practical skills training using simulation provides an opportunity to learn and gain confidence with this invasive procedure. Our objective was to assess the perceived educational value of 2 versions of an abscess model as part of an educational workshop for teaching I&D. METHODS: A combined didactic and practical skills workshop was developed for use at 2 national conferences. The didactic content was created through an iterative process. To facilitate hands-on training, 2 versions of an abscess model were created: 1 constructed from a negative mold and the other using a 3-dimensional printer. Participants were surveyed regarding prior experience with I&D, procedural confidence, and perceptions of the educational utility of the models. RESULTS: Seventy physicians and 75 nurse practitioners participated in the study. Procedural confidence improved after training using each version of the model, with the greatest improvements noted among novice learners. Ninety-four percent of physicians, and 99% of nurse practitioners rated the respective models as either "educational" or "very educational," and 97% and 100%, respectively, would recommend the abscess models to others. CONCLUSIONS: A combined didactic and practical skills educational workshop using novel abscess models was effective at improving learners' confidence. Our novel models provide an effective strategy for teaching procedural skills such as I&D and demonstrate a novel use of 3-dimensional printers in medical education. Further study is needed to determine if these educational gains translate into improvement in clinical performance or patient outcomes.

Continuing megathrust earthquake potential in Chile after the 2014 Iquique earthquake.

The seismic gap theory identifies regions of elevated hazard based on a lack of recent seismicity in comparison with other portions of a fault. It has successfully explained past earthquakes (see, for example, ref. 2) and is useful for qualitatively describing where large earthquakes might occur. A large earthquake had been expected in the subduction zone adjacent to northern Chile, which had not ruptured in a megathrust earthquake since a M âˆ¼8.8 event in 1877. On 1 April 2014 a M 8.2 earthquake occurred within this seismic gap. Here we present an assessment of the seismotectonics of the March-April 2014 Iquique sequence, including analyses of earthquake relocations, moment tensors, finite fault models, moment deficit calculations and cumulative Coulomb stress transfer. This ensemble of information allows us to place the sequence within the context of regional seismicity and to identify areas of remaining and/or elevated hazard. Our results constrain the size and spatial extent of rupture, and indicate that this was not the earthquake that had been anticipated. Significant sections of the northern Chile subduction zone have not ruptured in almost 150 years, so it is likely that future megathrust earthquakes will occur to the south and potentially to the north of the 2014 Iquique sequence.

An extracorporeal membrane oxygenation cannulation curriculum featuring a novel integrated skills trainer leads to improved performance among pediatric cardiac surgery trainees.

INTRODUCTION: American Heart Association guidelines recommend timely extracorporeal membrane oxygenation (ECMO) cannulation during cardiopulmonary resuscitation for pediatric cardiac arrest refractory to conventional resuscitation. Traditional cannulation training relies on the apprenticeship model. We hypothesized that a simulation-based ECMO cannulation curriculum featuring a novel integrated skills trainer would improve ECMO cannulation during cardiopulmonary resuscitation performance by cardiothoracic surgery trainees. METHODS: An embedded surgical neck cannulation trainer, designed in collaboration with expert surgeons, formed the focus for a simulation-based cannulation curriculum. The course included a didactic presentation and 2 neck cannulations during cardiopulmonary resuscitation with video-assisted expert feedback with a further cannulation at 3 months. Primary outcome was time to cannulation on the trainer. Secondary outcomes were performance on a validated Global Rating Scale (GRS) of surgical technique and a novel Composite ECMO Cannulation Score (CECS). RESULTS: Ten cardiothoracic surgery trainees participated. The trainer was rated as authentic, and sessions was rated as highly useful. Median time to cannulation decreased between cannulation 1 and 2 (15 minutes 24 seconds vs. 12 minutes 15 seconds, P = 0.002). Improvement was sustained at 3 months (13 minutes 36 seconds, P = 0.157 vs. attempt 2). Likewise, GRS increased significantly at attempt 2 versus 1 (77% vs. 62%, P = 0.003) as did CECS (88% vs. 52%, P = 0.002). No deterioration in GRS or CECS was measured at 3 months. CONCLUSIONS: Cardiothoracic surgery trainees found a contextualized ECMO cannulation during cardiopulmonary resuscitation cannulation curriculum to be highly useful and demonstrated sustained improvement in time to cannulation, CECS, and GRS. Further work will focus on determining the clinical impact of this training and defining the optimal interval and number of training sessions.

Simulation-based training delivered directly to the pediatric cardiac intensive care unit engenders preparedness, comfort, and decreased anxiety among multidisciplinary resuscitation teams.

OBJECTIVES: Resuscitation of pediatric cardiac patients involves unique and complex physiology, requiring multidisciplinary collaboration and teamwork. To optimize team performance, we created a multidisciplinary Crisis Resource Management training course that addressed both teamwork and technical skill needs for the pediatric cardiac intensive care unit. We sought to determine whether participation improved caregiver comfort and confidence levels regarding future resuscitation events. METHODS: We developed a simulation-based, in situ Crisis Resource Management curriculum using pediatric cardiac intensive care unit scenarios and unit-specific resuscitation equipment, including an extracorporeal membrane oxygenation circuit. Participants replicated the composition of a clinical team. Extensive video-based debriefing followed each scenario, focusing on teamwork principles and technical resuscitation skills. Pre- and postparticipation questionnaires were used to determine the effects on participants' comfort and confidence regarding participation in future resuscitations. RESULTS: A total of 182 providers (127 nurses, 50 physicians, 2 respiratory therapists, 3 nurse practitioners) participated in the course. All participants scored the usefulness of the program and scenarios as 4 of 5 or higher (5 = most useful). There was significant improvement in participants' perceived ability to function as a code team member and confidence in a code (P < .001). Participants reported they were significantly more likely to raise concerns about inappropriate management to the code leader (P < .001). CONCLUSIONS: We developed a Crisis Resource Management training program in a pediatric cardiac intensive care unit to teach technical resuscitation skills and improve team function. Participants found the experience useful and reported improved ability to function in a code. Further work is needed to determine whether participation in the Crisis Resource Management program objectively improves team function during real resuscitations.