Experience curves as an organizing framework for deliberate practice in emergency medicine learning.

Deliberate practice is an important skill-training strategy in emergency medicine (EM) education. Learning curves display the relationship between practice and proficiency. Forgetting curves show the opposite, and demonstrate how skill decays over time when it is not reinforced.

Gartland type I supracondylar humerus fractures in children: is splint immobilization enough?

Objective: The primary objective of this study was to determine if Gartland type I supracondylar humerus (SCH) fractures undergo significant displacement resulting in a change in management when treated with a long-arm splint. Secondary objectives included measured changes at follow-up in displacement and/or angulation.

Methods: This was a retrospective review of children who presented with elbow injuries to a children's hospital.

Performance of the Canadian Triage and Acuity Scale for children: a multicenter database study.

Study Objective: We evaluate the association between triage levels assigned using the Canadian Triage and Acuity Scale and surrogate markers of validity for real-life children triaged in multiple emergency departments (EDs).

Methods: This was a retrospective cohort study evaluating the triage assessment and outcomes of all children presenting to 12 pediatric EDs, all of which are members of the Pediatric Emergency Research Canada group, during a 1-year period (2010 to 2011). Anonymous data were retrieved from the ED computerized databases.

Value of information methods for planning and analyzing clinical studies optimize decision making and research planning.

Objective: The results of two randomized clinical trials (RCTs) demonstrate the clinical effectiveness of alternatives to casting for certain ankle and wrist fractures. We illustrate the use of value of information (VOI) methods for evaluating the evidence provided by these studies with respect to decision making.

Study Design And Setting: Using cost-effectiveness data from these studies, the expected value of sample information (EVSI) of a future RCT can be determined.

On the inverse temperature transition and development of an entropic elastomeric force of the elastin mimetic peptide [LGGVG](3, 7).

We report on a molecular dynamics simulation based study of the thermal and mechanical properties of the elastin mimetic peptide [LGGVG](n) (n = 3, 7). Our findings indicate that this peptide undergoes an inverse temperature transition as the temperature is raised from ~20 °C to 42 °C. The thermal behavior is similar to what has been observed in other well studied short mimetic peptides of elastin.

Prevalence of abnormal cases in an image bank affects the learning of radiograph interpretation.

Objectives: Using a large image bank, we systematically examined how the use of different ratios of abnormal to normal cases affects trainee learning.

Methods: This was a prospective, double-blind, randomised, three-arm education trial conducted in six academic training programmes for emergency medicine and paediatric residents in post-licensure years 2-5. We developed a paediatric ankle trauma radiograph case bank.

The Canadian Triage and Acuity Scale for children: a prospective multicenter evaluation.

Study Objective: The aims of the study are to measure both the interrater agreement of nurses using the Canadian Triage and Acuity Scale in children and the validity of the scale as measured by the correlation between triage level and proxy markers of severity.

Methods: This was a prospective multicenter study of the reliability and construct validity of the Canadian Triage and Acuity Scale in 9 tertiary care pediatric emergency departments (EDs) across Canada during 2009 to 2010. Participants were a sample of children initially triaged as Canadian Triage and Acuity Scale level 2 (emergency) to level 5 (nonurgent).

Thermal hysteresis in the backbone and side-chain dynamics of the elastin mimetic peptide [VPGVG]3 revealed by 2H NMR.

We report on experimental measurements of the backbone and side-chain dynamics of the elastin mimetic peptide [VPGVG](3) by (2)H NMR echo spectroscopy and 2D T(1)-T(2) correlation relaxometry. The T(1) and T(2) relaxation times of the Gly α-deuterons and Val α-, β-, and γ-deuterons of a hydrated sample reveal a thermal hysteresis when the temperature is raised from -10 to 45 °C and then subsequently cooled back to -10 °C. In addition, near 30 °C we observe a reduction in the slope of the T(1)(T) and T(2)(T) heating curves, indicating a structural change that appears to be correlated well to the known inverse temperature transition of this peptide.

NMR studies of localized water and protein backbone dynamics in mechanically strained elastin.

We report on measurements of the dynamics of localized waters of hydration and the protein backbone of elastin, a remarkable resilient protein found in vertebrate tissues, as a function of the applied external strain. Using deuterium 2D T(1)-T(2) NMR, we separate four reservoirs in the elastin-water system characterized by water with distinguishable mobilities. The measured correlation times corresponding to random tumbling of water localized to the protein is observed to decrease with increasing strain and is interpreted as an increase in its orientational entropy.

Measurement of the Exchange Rate of Waters of Hydration in Elastin by 2D T(2)-T(2) Correlation Nuclear Magnetic Resonance Spectroscopy.

We report on the direct measurement of the exchange rate of waters of hydration in elastin by T(2)-T(2) exchange spectroscopy. The exchange rates in bovine nuchal ligament elastin and aortic elastin at temperatures near, below and at the physiological temperature are reported. Using an Inverse Laplace Transform (ILT) algorithm, we are able to identify four components in the relaxation times.

Investigation of the effect of a variety of pulse errors on spin I=1 quadrupolar alignment echo spectroscopy.

We report on an analysis of a well known three-pulse sequence for generating and detecting spin I=1 quadrupolar order when various pulse errors are taken into account. In the situation of a single quadrupolar frequency, such as the case found in a single crystal, we studied the potential leakage of single and/or double quantum coherence when a pulse flip error, finite pulse width effect, RF transient or a resonance offset is present. Our analysis demonstrates that the four-step phase cycling scheme studied is robust in suppressing unwanted double and single quantum coherence as well as Zeeman order that arise from the experimental artifacts, allowing for an unbiased measurement of the quadrupolar alignment relaxation time, T(1Q).

How much practice is enough? Using learning curves to assess the deliberate practice of radiograph interpretation.

Purpose: To demonstrate how learning curves can describe proficiency improvements associated with deliberate practice of radiograph interpretation.

Method: This was a prospective, cross-sectional study of pediatric residents in two tertiary care programs. A 234-item digital case bank of pediatric ankle radiographs was developed.

Cost-effectiveness analysis of cast versus splint in children with acceptably angulated wrist fractures.

Objectives: In a practice setting where casting is considered the standard of care, the aim of this study was to assess the cost-effectiveness of wrist splints compared with routine casting in children with acceptably angulated distal radius greenstick or transverse fractures.

Methods: A cost-effectiveness analysis was conducted alongside a randomized controlled trial (RCT). One hundred children with acceptably angulated distal radius greenstick or transverse fractures received either a wrist splint or cast.

The treatment of pediatric gastroenteritis: a comparative analysis of pediatric emergency physicians' practice patterns.

Objectives: Acute gastroenteritis is a very common emergency department (ED) diagnosis accounting for greater than 1.5 million outpatient visits and 200,000 hospitalizations annually among children in the United States. Although guidelines exist to assist clinicians, they do not clearly address topics for which evidence is new or limited, including the use of antiemetic agents, probiotics, and intravenous (IV) fluid rehydration regimens.

Wide-beam reconstruction half-time SPECT improves diagnostic certainty and preserves normalcy and accuracy: a quantitative perfusion analysis.

Background: Filtered back-projection (FBP) has been a standard in SPECT imaging. Newer iterative reconstruction algorithms have been shown to improve image quality and shorten acquisition time by taking into account statistical nature of raw data and using resolution recovery (RR). Wide-beam reconstruction (WBR) is an iterative algorithm with RR and adaptive noise control.

North American practice patterns of intravenous magnesium therapy in severe acute asthma in children.

Objectives: Although intravenous (IV) magnesium (Mg) can decrease hospitalizations in children with severe acute asthma, its use is often limited to resistant disease, and disposition may be determined prior to its use. Since knowledge about practice patterns of IV Mg would enhance knowledge translation and guide future research, we surveyed pediatric emergency physicians with interest in clinical research to determine the frequency, indications, adverse events, and barriers to use of IV Mg in children with severe acute asthma.

Methods: A cross-sectional online survey of two national pediatric emergency physician associations in Canada and the United States was conducted using a modified Dillman technique.

Cast versus splint in children with minimally angulated fractures of the distal radius: a randomized controlled trial.

Background: Minimally angulated fractures of the distal radius are common in children and have excellent outcomes. We conducted a randomized controlled trial to determine whether the use of a prefabricated splint is as effective as a cast in the recovery of physical function.

Methods: We included 96 children 5 to 12 years of age who were treated for a minimally angulated (≤ 15°) greenstick or transverse fracture of the wrist between April 2007 and September 2009 at a tertiary care pediatric hospital.

Assessing the palatability of oral rehydration solutions in school-aged children: a randomized crossover trial.

Objective: To compare the palatability of 3 oral rehydration solutions.

Design: Prospective, blinded, randomized, 3-period, 3-treatment crossover trial.

Setting: Emergency department of a tertiary care pediatric hospital.

Pediatric emergency physician opinions on ankle radiograph clinical decision rules.

Objectives: The Low Risk Ankle Rule (LRAR) is a validated clinical decision rule (CDR) about the indications for ankle radiographs in children with acute blunt ankle trauma. Although application of the LRAR has the potential to safely reduce the rate of ankle radiography by 60%, current x-ray rates in most emergency departments (EDs) in the United States and Canada remain unnecessarily high (85%-100%). To evaluate this gap between knowledge and practice, physicians who treat pediatric ankle injuries in EDs were surveyed to determine physician awareness and use of the LRAR, acceptability of the LRAR as measured by the Ottawa Acceptability for Decision Rules Scale (OADRS), and perceived barriers to the use of a validated pediatric ankle x-ray rule.

Magnetic resonance imaging of clinically suspected Salter-Harris I fracture of the distal fibula.

Objectives: In skeletally immature children, isolated lateral ankle injuries without radiograph-visible fractures are often diagnosed with Salter-Harris I fractures of the distal fibula (SH1DF). However, recent magnetic resonance imaging (MRI) evidence in children suggests that sprains may be more common than previously thought. Thus, the main objective of this study was to determine the rate of MRI-confirmed SH1DF among cases where this diagnosis was made presumptively, based on clinical findings.

Investigation of the dynamical properties of water in elastin by deuterium Double Quantum Filtered NMR.

The anisotropic motion of tightly bound waters of hydration in bovine nuchal ligament elastin has been studied by deuterium Double Quantum Filtered (DQF) NMR. The experiments have allowed for a direct measurement of the degree of anisotropy within pores of elastin over a time scale ranging from 100 micros to 30 ms, corresponding to a tortuous spatial displacement ranging from 0.2 to 7 microm.

Simulation studies of instrumental artifacts on spin I=1 double quantum filtered NMR spectroscopy.

We report on the results of a simulation based study of the effect of various experimental artifacts for spin I=1 double quantum filtered NMR. The simulation captures the effects of static field inhomogeneity, finite pulse widths, phase errors, transients and radio frequency field inhomogeneity. We simulated the spectral distortions introduced under these errors for four, eight and sixteen step phase cycles that are well known in the NMR community.

Matrix metalloproteinases and proangiogenic factors in testicular germ cell tumors.

Purpose: Testicular cancer is the most frequent solid tumor in young male adults and a disease with elusive pathogenesis. The purpose of this study was to determine the role of matrix metalloproteinases and angiogenic factors in the pathogenesis of testicular germ cell tumors (GCTs).

Methods: Between 2003 and 2006 we measured the serum levels of matrix metalloproteinase 2 (MMP-2), matrix metalloproteinase 9 (MMP-9), tissue inhibitor of matrix metalloproteinase 2 (TIMP-2), vascular endothelial growth factor A (VEGF-A), basic fibroblast growth factor (bFGF), platelet derived growth factor BB (PDGF-BB) and angiopoietin 2 (Ang-2) in 50 patients with testicular GCTs, at baseline, one month after the completion of the second cycle of chemotherapy and one year after the completion of chemotherapy, and in 16 male age-matched controls at baseline.