Accuracy Screening for ST Elevation Myocardial Infarction in a Task-switching Simulation.

INTRODUCTION: Interruptions in the emergency department (ED) are associated with clinical errors, yet are important when providing care to multiple patients. Screening triage electrocardiograms (ECG) for ST-segment elevation myocardial infarction (STEMI) represent a critical interrupting task that emergency physicians (EP) frequently encounter. To address interruptions such as ECG interpretation, many EPs engage in task switching, pausing their primary task to address an interrupting task. The impact of task switching on clinical errors in interpreting screening ECGs for STEMI remains unknown. METHODS: Resident and attending EPs were invited to participate in a crossover simulation trial. Physicians first completed a task-switching simulation in which they viewed patient presentations interrupted by clinical tasks, including screening ECGs requiring immediate interpretation before resuming the patient presentation. Participants then completed an uninterrupted simulation in which patient presentations and clinical tasks were completed sequentially without interruption. The primary outcome was accuracy of ECG interpretation for STEMI during task switching and uninterrupted simulations. RESULTS: Thirty-five participants completed the study. We found no significant difference in accuracy of ECG interpretation for STEMI (task switching 0.89, uninterrupted 0.91, paired t-test p=0.21). Attending physician status (odds ratio [OR] [2.56], confidence interval [CI] [1.66-3.94], p<0.01) and inferior STEMI (OR [0.08], CI [0.04-0.14], p<0.01) were associated with increased and decreased odds of correct interpretation, respectively. Low self-reported confidence in interpretation was associated with decreased odds of correct interpretation in the task-switching simulation, but not in the uninterrupted simulation (interaction p=0.02). CONCLUSION: In our simulation, task switching was not associated with overall accuracy of ECG interpretation for STEMI. However, odds of correct interpretation decreased with inferior STEMI ECGs and when participants self-reported low confidence when interrupted. Our study highlights opportunities to improve through focused ECG training, as well as self-identification of "high-risk" screening ECGs prone to error during interrupted clinical workflow.

Risk factors can classify individuals who develop accelerated knee osteoarthritis: Data from the osteoarthritis initiative.

We assessed which combinations of risk factors can classify adults who develop accelerated knee osteoarthritis (KOA) or not and which factors are most important. We conducted a case-control study using data from baseline and the first four annual visits of the Osteoarthritis Initiative. Participants had no radiographic KOA at baseline (Kellgren-Lawrence [KL]<2). We classified three groups (matched on sex): (i) accelerated KOA: >1 knee developed advance-stage KOA (KL = 3 or 4) within 48 months; (ii) typical KOA: >1 knee increased in radiographic scoring (excluding those with accelerated KOA); and (iii) No KOA: no change in KL grade by 48 months. We selected eight predictors: Serum concentrations for C-reactive protein, glycated serum protein (GSP), and glucose; age; sex; body mass index; coronal tibial slope, and femorotibial alignment. We performed a classification and regression tree (CART) analysis to determine rules for classifying individuals as accelerated KOA or not (no KOA and typical KOA). The most important baseline variables for classifying individuals with incident accelerated KOA (in order of importance) were age, glucose concentrations, BMI, and static alignment. Individuals <63.5 years were likely not to develop accelerated KOA, except when overweight. Individuals >63.5 years were more likely to develop accelerated KOA except when their glucose levels were >81.98 mg/dl and they did not have varus malalignment. The unexplained variance of the CART = 69%. These analyses highlight the complex interactions among four risk factors that may classify individuals who will develop accelerated KOA but more research is needed to uncover novel risk factors. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:876-880, 2018.

Serum Predictors of Percent Lean Mass in Young Adults.

Lustgarten, MS, Price, LL, Phillips, EM, Kirn, DR, Mills, J, and Fielding, RA. Serum predictors of percent lean mass in young adults. J Strength Cond Res 30(8): 2194-2201, 2016-Elevated lean (skeletal muscle) mass is associated with increased muscle strength and anaerobic exercise performance, whereas low levels of lean mass are associated with insulin resistance and sarcopenia. Therefore, studies aimed at obtaining an improved understanding of mechanisms related to the quantity of lean mass are of interest. Percent lean mass (total lean mass/body weight × 100) in 77 young subjects (18-35 years) was measured with dual-energy x-ray absorptiometry. Twenty analytes and 296 metabolites were evaluated with the use of the standard chemistry screen and mass spectrometry-based metabolomic profiling, respectively. Sex-adjusted multivariable linear regression was used to determine serum analytes and metabolites significantly (p ≤ 0.05 and q ≤ 0.30) associated with the percent lean mass. Two enzymes (alkaline phosphatase and serum glutamate oxaloacetate aminotransferase) and 29 metabolites were found to be significantly associated with the percent lean mass, including metabolites related to microbial metabolism, uremia, inflammation, oxidative stress, branched-chain amino acid metabolism, insulin sensitivity, glycerolipid metabolism, and xenobiotics. Use of sex-adjusted stepwise regression to obtain a final covariate predictor model identified the combination of 5 analytes and metabolites as overall predictors of the percent lean mass (model R = 82.5%). Collectively, these data suggest that a complex interplay of various metabolic processes underlies the maintenance of lean mass in young healthy adults.

Changes in flare after intravitreal injection of three different anti-vascular endothelial growth factor medications.

PURPOSE: To compare the change in anterior chamber flare after intravitreal injection of the anti-vascular endothelial growth factor agents bevacizumab, aflibercept, and ranibizumab. METHODS: Sixty-one eyes of 53 patients underwent intravitreal injection with anti-vascular endothelial growth factor medications for exudative age-related macular degeneration, diabetic macular edema, or retinal vein occlusion. There were a total of 26 eyes injected with bevacizumab, 14 eyes injected with aflibercept, and 21 eyes injected with ranibizumab. Anterior segment flare was measured with a laser flare meter (Kowa) before intravitreal injection and 1 day after injection. The change in flare was analyzed. RESULTS: The mean change in flare after 1 day was +2.5 photons per millisecond in patients who received bevacizumab, 0.0 photons per millisecond for aflibercept, and -0.2 photons per millisecond for ranibizumab. There was a statistically significant difference between the 3 medications (P = 0.006). Pairwise analysis of the change in flare showed a statistically significant difference between bevacizumab and ranibizumab (P = 0.002). The change in flare in patients who received aflibercept was not different from that in those who received bevacizumab (P = 0.08) or ranibizumab (P = 0.99). CONCLUSION: There was a statistically significant increase in flare after bevacizumab injection compared with ranibizumab. This difference was small and is not believed to be clinically significant. There was no statistical difference in the change in flare between aflibercept and the other medications, although the number of eyes in the aflibercept group was small.

Metabolites related to gut bacterial metabolism, peroxisome proliferator-activated receptor-alpha activation, and insulin sensitivity are associated with physical function in functionally-limited older adults.

Identification of mechanisms underlying physical function will be important for addressing the growing challenge that health care will face with physical disablement in the expanding aging population. Therefore, the goals of the current study were to use metabolic profiling to provide insight into biologic mechanisms that may underlie physical function by examining the association between baseline and the 6-month change in serum mass spectrometry-obtained amino acids, fatty acids, and acylcarnitines with baseline and the 6-month change in muscle strength (leg press one repetition maximum divided by total lean mass, LP/Lean), lower extremity function [short physical performance battery (SPPB)], and mobility (400 m gait speed, 400-m), in response to 6 months of a combined resistance exercise and nutritional supplementation (whey protein or placebo) intervention in functionally-limited older adults (SPPB ≤ 10; 70-85 years, N = 73). Metabolites related to gut bacterial metabolism (cinnamoylglycine, phenol sulfate, p-cresol sulfate, 3-indoxyl sulfate, serotonin, N-methylproline, hydrocinnamate, dimethylglycine, trans-urocanate, valerate) that are altered in response to peroxisome proliferator-activated receptor-alpha (PPAR-α) activation (α-hydroxyisocaproate, α-hydroxyisovalerate, 2-hydroxy-3-methylvalerate, indolelactate, serotonin, 2-hydroxypalmitate, glutarylcarnitine, isobutyrylcarnitine, cinnamoylglycine) and that are related to insulin sensitivity (monounsaturated fatty acids: 5-dodecenoate, myristoleate, palmitoleate; γ-glutamylamino acids: γ-glutamylglutamine, γ-glutamylalanine, γ-glutamylmethionine, γ-glutamyltyrosine; branched-chain amino acids: leucine, isoleucine, valine) were associated with function at baseline, with the 6-month change in function or were identified in backward elimination regression predictive models. Collectively, these data suggest that gut microbial metabolism, PPAR-α activation, and insulin sensitivity may be involved in mechanisms that underlie physical function in functionally-limited older adults.

An evaluation of the reliability of muscle fiber cross-sectional area and fiber number measurements in rat skeletal muscle.

BACKGROUND: The reliability of estimating muscle fiber cross-sectional area (measure of muscle fiber size) and fiber number from only a subset of fibers in rat hindlimb muscle cross-sections has not been systematically evaluated. This study examined the variability in mean estimates of fiber cross-sectional area as a function of the number of fibers measured, and tested whether counting a subset of fibers in a cross-section could predict total fiber number in middle-aged rats. RESULTS: Soleus and extensor digitorum longus (EDL) muscle cross-sections from 23-month-old, male Fisher 344 x Brown Norway rats were stained for myofibrillar ATPase activity to identify muscle fiber type (either type I [slow-twitch] or II [fast-twitch]) and laminin to facilitate fiber cross-sectional measurements. We outlined the circumference of 1000 to 1600 single muscle fibers for measurement of fiber cross-sectional area within muscle sections. Mean type I fiber cross-sectional area was based on soleus muscle sections which were predominantly composed of type I muscle fibers. Mean type II fiber cross-sectional area was based on EDL muscle sections which were predominantly composed of type II muscle fibers. A bootstrapping resampling technique demonstrated that variability in sampling distribution of mean type I and II fiber cross-sectional areas decreased and gradually stabilized as the number of fibers measured increased with large declines in variability occurring at numbers below 150 fibers. Coefficients of variation for bootstrapped mean type I fiber cross-sectional areas were lower than for type II. In the same muscle sections, total fiber number was compared to fiber numbers within 1, 2, 3, and 4 fixed field areas (10x magnification; 1000 x 1500 pixels in size/field) on the cross-section. Fiber numbers from 3 to 4 fields (approximating 15 to 20% of the cross-section) provided a reasonably predictive value of total fiber number (r=0.57-0.59, P=0.003). CONCLUSIONS: These data describe a pattern of improved precision in estimating mean fiber cross-sectional area as sample size of fibers measured increases to at least 150 in this rat model. Counting 15-20% of the fibers in cross-sections provides a reasonably reliable estimate of the total fiber number.

Relationship of bone mineral density to progression of knee osteoarthritis.

OBJECTIVE: To evaluate the longitudinal relationship between bone mineral density (BMD) and BMD changes and the progression of knee osteoarthritis (OA), as measured by cartilage outcomes. METHODS: We used observational cohort data from the Vitamin D for Knee Osteoarthritis trial. Bilateral femoral neck BMD values as well as knee magnetic resonance imaging (MRI) scans in each subject were obtained at baseline and subsequently at 12 months and 24 months. The change in total cartilage volume and tibial and femoral cartilage thickness was measured by manual cartilage segmentation of 2 sequential knee MRI scans in each subject. Multivariable linear regression models were used to examine the associations of baseline BMD and BMD change with the cartilage outcomes, adjusting for baseline age, sex, body mass index, malalignment, and vitamin D treatment. Model fit and assumptions were validated. RESULTS: A total of 127 subjects were eligible for analysis. Longitudinal BMD loss was associated with loss of cartilage volume (ß = 1.25 per 0.1 gm/cm(2) , P = 0.02) and loss of tibial cartilage thickness (ß = 0.028, P = 0.03). BMD loss of a magnitude greater than the least significant change (<-4.7%) was associated with 1.02% cartilage volume loss per year (P = 0.005), 0.014 mm femoral cartilage thickness loss (P = 0.04), and 0.021 mm tibial cartilage thickness loss per year (P = 0.009). There were no significant associations between baseline BMD and any of the cartilage outcomes. CONCLUSION: Longitudinal BMD loss is associated with progressive cartilage loss in knees with OA. Further work to clarify the basis of this relationship could reveal novel therapeutic targets for knee OA.

Use of pimobendan in 170 cats (2006-2010).

HYPOTHESIS/OBJECTIVES: To describe the therapeutic use of pimobendan in cats, describe the patient population to which it was administered, document potential side effects and report the clinical course following administration of pimobendan in conjunction with standard heart failure therapy. It is hypothesized that cats with advanced heart disease including congestive heart failure from a variety of causes will tolerate pimobendan with a minimum of side effects when used in treatment in conjunction with a variety of other medications. ANIMALS, MATERIALS AND METHODS: One hundred and seventy client owned cats with naturally occurring heart disease, one hundred and sixty four of which had congestive heart failure. Medical records were reviewed and owners and referring veterinarians were contacted for follow-up data. Data collected included pimobendan dose, other medications administered concurrently, data collected at physical examination, presence or absence of heart failure, adverse effects, classification of heart disease, echocardiographic data and survival time. The data were analyzed for significance between the initial visit and any follow-up visits. RESULTS: All cats were treated with pimobendan. The median pimobendan dose was 0.24 mg/kg q 12 h. Pimobendan was used in combination with multiple concurrent medications including angiotensin converting enzyme inhibitors, diuretics and anti-thrombotics. Five cats (3.0%) had potential side effects associated with pimobendan. One cat (0.6%) had presumed side effects severe enough to discontinue pimobendan use. Median survival time for 164 cats with congestive heart failure after initiation of pimobendan was 151 days (range 1-870). CONCLUSION: Pimobendan appears to be well tolerated in cats with advanced heart disease when used with a variety of concurrent medications. Randomized controlled studies need to be performed to accurately assess whether it is efficacious for treatment of congestive heart failure in cats.

Therapeutic trajectory of hyaluronic acid versus corticosteroids in the treatment of knee osteoarthritis: a systematic review and meta-analysis.

OBJECTIVE: To compare the efficacy of intraarticular hyaluronic acid with corticosteroids for knee osteoarthritis (OA). METHODS: Our data sources were Medline, EMBASE, CINAHL, BIOSIS, and the Cochrane database, as well as hand- searched reviews, manuscripts, and supplements. For unpublished data we used author contacts. Randomized trials that reported effects of intraarticular hyaluronic acid versus corticosteroids on knee OA were selected based on inclusion criteria. Two reviewers extracted data independently. Using a random-effects model, we computed effect sizes for pain change from baseline at 2, 4, 8, 12, and 26 weeks. We also performed multivariate analyses accounting for within and between-study covariance. We performed sensitivity analyses for trials that reported intent-to-treat (ITT) analysis and blinding, and directly compared Hyalgan with methylprednisolone. RESULTS: The 7 eligible trials included 606 participants. Five reported ITT analyses. At week 2 the effect size was -0.39 (95% confidence interval [95% CI], -0.65, -0.12) favoring corticosteroids; at week 4 it was -0.01 (95% CI -0.23, 0.21) suggesting equal efficacy. At week 8 the effect size was 0.22 (95% CI -0.05, 0.49) favoring hyaluronic acid, and at week 12 it was 0.35 (95% CI 0.03, 0.66) favoring hyaluronic acid. At week 26 the effect size was 0.39 (95% CI 0.18, 0.59), favoring hyaluronic acid. The multivariate analyses and sensitivity analyses generated consistent results. CONCLUSION: From baseline to week 4, intraarticular corticosteroids appear to be relatively more effective for pain than intraarticular hyaluronic acid. By week 4, the 2 approaches have equal efficacy, but beyond week 8, hyaluronic acid has greater efficacy. Understanding this trend is useful to clinicians when treating knee OA.

Improving the reliability of physician performance assessment: identifying the "physician effect" on quality and creating composite measures.

BACKGROUND: The proliferation of efforts to assess physician performance underscore the need to improve the reliability of physician-level quality measures. OBJECTIVE: Using diabetes care as a model, to address 2 key issues in creating reliable physician-level quality performance scores: estimating the physician effect on quality and creating composite measures. DESIGN: Retrospective longitudinal observational study. SUBJECTS: A national sample of physicians (n = 210) their patients with diabetes (n = 7574) participating in the National Committee on Quality Assurance-American Diabetes Association's Diabetes Provider Recognition Program. MEASURES: Using 11 diabetes process and intermediate outcome quality measures abstracted from the medical records of participants, we tested each measure for the magnitude of physician-level variation (the physician effect or "thumbprint"). We then combined measures with a substantial physician effect into a composite, physician-level diabetes quality score and tested its reliability. RESULTS: We identified the lowest target values for each outcome measure for which there was a recognizable "physician thumbprint" (ie, intraclass correlation coefficient > or =0.30) to create a composite performance score. The internal consistency reliability (Cronbach's alpha) of the composite score, created by combining the process and outcome measures with an intraclass correlation coefficient > or =0.30, exceeded 0.80. The standard errors of the composite case-mix adjusted score were sufficiently small to discriminate those physicians scoring in the highest from those scoring in the lowest quartiles of the quality of care distribution with no overlap. CONCLUSIONS: We conclude that the aggregation of well-tested quality measures that maximize the "physician effect" into a composite measure yields reliable physician-level quality of care scores for patients with diabetes.

Eighteen year (1985-2002) analysis of incidence, mortality, and cardiac procedure outcomes of acute myocardial infarction in patients > or = 65 years of age.

The temporal patterns of outcomes and therapy in patients aged > or =65 years with acute myocardial infarctions (AMIs) from a national database were examined to better understand this increasingly important demographic group. The National Hospital Discharge Survey (NHDS), a nationally representative sample of acute care hospitals in the United States, was used for analysis. Using International Classification of Diseases, Ninth Revision, Clinical Modification codes, hospitalizations with first-listed diagnoses of AMI from 1985 to 2002 were identified. A multivariate logistic regression model was developed to identify predictors of mortality in these patients. The logit of propensity score was used as an adjuster for reducing the bias of nonrandom assignment of cardiovascular procedures. Although the number of patients aged > or =65 years admitted with AMIs increased over the study period, the incidence in patients aged > or =65 years decreased by 1.5%. In patients aged <65 years, the incidence was significantly lower for any year and decreased by 17.5%. The in-hospital mortality rate in patients aged > or =65 years decreased (from 22.0% in 1985 to 11.5% in 2002) but remained significantly higher compared with younger patients (from 7.0% in 1985 to 3.2% in 2002). Overall cardiac procedure use increased from 18.0% in 1985 to 50.7% in 2002, but patients aged > or =65 years consistently underwent fewer procedures than younger patients. After taking 12 covariates into consideration, not undergoing a cardiac procedure remained a significant risk factor for mortality (odds ratio 3.13, p <0.0001). Acute renal failure (odds ratio 4.64, p <0.0001) and age > or =65 years (odds ratio 2.14, p <0.0001) were the other 2 strongest independent predictors of mortality. In conclusion, the incidence of AMI is decreasing. Over the 18-year period from 1985 to 2002, there was a significant reduction in mortality, but patients aged > or =65 years remained at particular risk. Multivariate analysis suggests that a lack of the use of procedures in these patients may at least partially explain their higher mortality.

Optical coherence tomography longitudinal evaluation of retinal nerve fiber layer thickness in glaucoma.

OBJECTIVES: To longitudinally evaluate optical coherence tomography (OCT) peripapillary retinal nerve fiber layer thickness measurements and to compare these measurements across time with clinical status and automated perimetry. METHODS: Retrospective evaluation of 64 eyes (37 patients) of glaucoma suspects or patients with glaucoma participating in a prospective longitudinal study. All participants underwent comprehensive clinical assessment, visual field (VF) testing, and OCT every 6 months. Field progression was defined as a reproducible decline of at least 2 dB in VF mean deviation from baseline. Progression of OCT was defined as reproducible mean retinal nerve fiber layer thinning of at least 20 mum. RESULTS: Each patient had a median of 5 usable OCT scans at median follow-up of 4.7 years. The difference in the linear regression slopes of retinal nerve fiber layer thickness between glaucoma suspects and patients with glaucoma was nonsignificant for all variables; however, Kaplan-Meier survival curve analysis demonstrated a higher progression rate by OCT vs VF. Sixty-six percent of eyes were stable throughout follow-up, whereas 22% progressed by OCT alone, 9% by VF mean deviation alone, and 3% by VF and OCT. CONCLUSIONS: A greater likelihood of glaucomatous progression was identified by OCT vs automated perimetry. This might reflect OCT hypersensitivity or true damage identified by OCT before detection by conventional methods.

Optical coherence tomography (OCT) macular and peripapillary retinal nerve fiber layer measurements and automated visual fields.

PURPOSE: To investigate the structure-function relationship between optical coherence tomography (OCT) macular retinal and peripapillary nerve fiber layer (NFL) thickness and automated visual field (VF) findings. DESIGN: Cross-sectional observational study. METHODS: Retrospective institutional study where 150 consecutive eyes (101 subjects) from a glaucoma service were included. All the participants had full ophthalmic evaluation, VF testing and prototype OCT scanning at the same visit. Orthogonal OCT macular analysis was obtained to maximize the sampling of the area of interest. Pearson age-adjusted correlation was determined between macular retinal thickness and peripapillary NFL thickness. Area under the receiver operator characteristics (AROC) curves for the association between macular retinal thickness and peripapillary NFL thickness and VF findings were calculated in a subgroup of eyes without VF defect and eyes with VF defect confined to one hemifield. RESULTS: The correlation between macular retinal and peripapillary NFL measurements ranged between r =.27 to.54 for quadrants,.44 to.55 for hemiretina, and.52 for the overall mean. Areas under the receiver operator characteristics for macular thickness were higher in areas corresponding to the VF defect location than the noncorresponding locations. Areas under the receiver operator characteristics for peripapillary NFL thickness were higher than for the macular retinal thickness. Including both macular retinal thickness and peripapillary NFL thickness measurements in the logistic regression model yielded AROCs (range:.69 -.77) similar to those found for the peripapillary NFL alone. CONCLUSION: Macular retinal thickness, as measured by OCT, was capable of detecting glaucomatous damage and corresponded with peripapillary NFL thickness; however, peripapillary NFL thickness had higher sensitivity and specificity for the detection of VF abnormalities.