Putting Theory to Practice: Applying Cognitive Load Theory to Resident Medical Education.

OBJECTIVE: We built 2 versions of an asynchronous pediatric orthopedic educational intervention for emergency medicine residents and sought to compare the two. We hypothesized that the version incorporating more instructional scaffolding in the form of a cognitive aid (CA) would optimize germane cognitive load for our target novice learners and result in higher test scores. METHODS: Learners were block randomized to either a "CA" or "non-CA" arm, each containing a random set of 18 modules. The CA arm incorporated an orthopedic fracture classification chart embedded within the diagnostic questions to guide the learner in forming a diagnosis. The non-CA arm was designed with more active learning as the classification chart was provided only after each diagnostic answer submission. For both arms, the final 6 modules completed per learner were scored. Learners also completed a perceived cognitive load assessment tool measured on a 10-point Likert scale. RESULTS: Learners in the non-CA arm had a mean total score on the testing modules of 33% correct compared with a mean total score of 44% correct for learners in the CA arm (mean difference, 11; 95% confidence interval, 4%-19%, P = 0.005). There was a trend for the CA arm to have lower perceived overall cognitive load scores; however, this did not reach statistical significance. CONCLUSIONS: Emergency medicine residents performed better after completing the CA version of our educational intervention. Applying cognitive load theory to an educational intervention may increase its success among target learners.

Management and Outcome of Pediatric Patients With Transient Small Bowel-Small Bowel Intussusception.

OBJECTIVE: The aim of this study was to assess the management and outcomes of healthy pediatric patients diagnosed radiologically with transient and benign small bowel-small bowel intussusception (SB-SBI). METHODS: Retrospective cohort study of healthy patients 0 to 18 years of age who presented to a children's hospital emergency department from January 1, 2005, to June 30, 2015, and had transient and benign SB-SBI characterized by spontaneous resolution (ie, transient), diameter of less than 2.5 cm, no lead point, normal bowel wall thickness, nondilated proximal small bowel, and no colonic involvement (ie, benign radiographic features). Charts were reviewed for demographics, clinical presentation, radiologic studies obtained, outcomes, and further management. Medical and radiologic records were also reviewed for 1 year after presentation for any subsequent pathologic diagnoses. RESULTS: Sixty-eight patients were included in our study, with a total of 87 episodes of transient and benign SB-SBI on initial or follow-up examination. Overall, 39 patients (57%) were admitted to the hospital, and 38 patients (56%) had a surgical consultation. Twenty-four patients (35%) had further radiologic studies obtained, including computed tomography scans, esophagogastroduodenoscopy, Meckel's scan, barium swallow studies, and magnetic resonance imaging. All studies were negative for concerning pathology including apparent lead points. None of the patients required surgical intervention or had any complications. CONCLUSIONS: Transient and benign SB-SBIs with reassuring radiologic and clinical features diagnosed in healthy pediatric patients are likely incidentally found and are unlikely to be associated with a pathologic lead point.

Management and Outcomes of Spontaneous Pneumomediastinum in Children.

OBJECTIVES: Management of spontaneous pneumomediastinum in the pediatric population is highly variable. There are limited data on the use of diagnostic tests and the need for admission. Our objectives were to characterize the management of pediatric spontaneous pneumomediastinum, determine the diagnostic yield of advanced imaging, and describe the patients' outcomes. METHODS: This is a retrospective cohort study of all patients presenting to a single tertiary pediatric emergency department between January 2008 and February 2015 diagnosed with pneumomediastinum. Patients were identified using 2 complementary strategies: International Classification of Diseases, Ninth Revision billing codes and a keyword search of the hospital radiology database. RESULTS: We identified 183 patients with spontaneous pneumomediastinum. The mean age was 12.8 ± 4.8 years. Diagnosis was established by chest radiograph (CXR) in 165 (90%) patients, chest computed tomography in 15 (8%), neck imaging in 2 (1%), and abdominal imaging in 1. After diagnosis, many patients underwent additional studies: repeat CXR (99, 54%), chest computed tomography (53, 29%), esophagram (45, 25%), and laryngoscopy (15, 8%). Seventy-eight percent of patients (n = 142) were admitted with a median length of stay of 27 hours (18.4-45.6 hours). Six patients returned to the emergency department within 96 hours for persistent chest pain; 2 were admitted, and 1 was found to have worsening pneumomediastinum on CXR. We performed a secondary analysis on 3 key subgroups: primary spontaneous pneumomediastinum (64, 35%), secondary gastrointestinal-associated pneumomediastinum (31, 17%), and secondary respiratory-associated pneumomediastinum (88, 48%). No patients in the study received an invasive intervention for pneumomediastinum. In all patients, further studies did not yield additional diagnostic information. CONCLUSIONS: Our data suggest that patients with spontaneous pneumomediastinum who are clinically well appearing can be managed conservatively with clinical observation, avoiding exposure to radiation and invasive procedures.

Rapid brain MRI protocols reduce head computerized tomography use in the pediatric emergency department.

BACKGROUND: Rapid magnetic resonance imaging (MRI) protocols may be effective in the emergency department (ED) to evaluate nontraumatic neurologic complaints. We evaluate neuroimaging (rapid MRI [rMRI]), head computerized tomography [HCT], and full MRI) use following widespread implementation of rMRI protocols in a pediatric emergency department (ED). METHODS: We conducted a retrospective study in a tertiary care pediatric ED of encounters with neuroimaging during two 9-month periods: one prior to (control period) and one after generalized availability of 4 rMRI protocols (rMRI period). The primary outcome was differences in neuroimaging rates between the two periods. Secondary outcomes included ED process measures, unsuccessful imaging, and undetected pathology, with full MRI within 14 days as the reference standard. RESULTS: There were 1052 encounters with neuroimaging during the control and 1308 during the rMRI periods. Differences in neuroimaging between periods were 27.7% for rMRI (95% CI, 24.4, 31.0), - 21.5% for HCT (95% CI, - 25.5, - 17.5), and - 6.2% for full MRI (95% CI, - 9.3, - 3.1%.) Time to imaging (182 [IQR 138-255] versus 86 [IQR 52-137] minutes) as well as ED length of stay (396 [IQR 304-484] versus 257 [IQR 196-334] minutes) was longer for rMRI versus HCT (p < 0.01). Between the control and rMRI periods, there were differences in types of neuroimaging performed for patients with altered mental status, headache, seizure, shunt dysfunction, stroke, syncope, trauma, vomiting, infection, and other neurologic complaints (p < 0.05). rMRI studies were unsuccessful in 3.6% of studies versus 0.0% of HCTs (p < 0.01). The 22 unsuccessful rMRI studies were unsuccessful due to artifacts from dental hardware (n = 2) and patient motion (n = 20). None of the rMRI studies with full MRI follow-up imaging had undetected pathology; the false negative rate for the HCT exams was as high as 25%. CONCLUSIONS: After routine ED use of 4 rMRI protocols, there was a more than 20% decrease in HCT use without missed diagnoses. Time to neuroimaging and length of stay were longer for rMRI than HCT, with higher rates of unsuccessful imaging. Despite these limitations, rMRI may be an alternative to HCT for nontraumatic complaints in the ED.

Implementation of a brain injury screen MRI for infants at risk for abusive head trauma.

BACKGROUND: Head computed tomography (CT) is the current standard of care for evaluating infants at high risk of abusive head trauma. OBJECTIVE: To both assess the feasibility of using a previously developed magnetic resonance imaging (MRI) brain injury screen (MRBRscreen) in the acute care setting in place of head CT to identify intracranial hemorrhage in high-risk infants and to compare the accuracy of a rapid imaging pulse sequence (single-shot T2 fast spin echo [ssT2FSE]) to a conventional pulse sequence (conventional T2 fast spin echo [conT2FSE]). MATERIALS AND METHODS: This was a quality improvement initiative to evaluate infants <12 months of age who were screened for intracranial hemorrhage using an MRBRscreen as part of clinical care. The MRBRscreen included axial conT2FSE, axial gradient recalled echo, coronal T1-weighted inversion recovery, axial diffusion-weighted image and an axial ssT2FSE. A comparison of ssT2FSE to conT2FSE with respect to lesion detection was also performed. RESULTS: Of 158 subjects, the MRBRscreen was able to be completed in 155 (98%); 9% (14/155) were abnormal. Ninety-four percent (137/145) of subjects underwent only an MRBRscreen and avoided both radiation from head CT and sedation from MRI. The axial ssT2FSE and conT2FSE results were congruent 99% of the time. CONCLUSION: An MRBRscreen in place of a head CT is feasible and potentially could decrease head CT use by more than 90% in this population. Using a rapid ssT2FSE in place of a conT2FSE can reduce total scan time without losing lesion detection. If an MRBRscreen is readily available, physicians' threshold to perform neuroimaging may be lowered and lead to earlier detection of abusive head trauma.

Neuroimaging of Peptide-based Vaccine Therapy in Pediatric Brain Tumors: Initial Experience.

The potential benefits of peptide-based immunotherapy for pediatric brain tumors are under investigation. Treatment-related heterogeneity has resulted in radiographic challenges, including pseudoprogression. Conventional MR imaging has limitations in assessment of different forms of treatment-related heterogeneity, particularly regarding distinguishing true tumor progression from efficacious treatment responses. Advanced neuroimaging techniques, including diffusion magnetic resonance (MR), perfusion MR, and MR spectroscopy, may add value in the assessment of treatment-related heterogeneity. Observations suggest that recent delineation of specific response criteria for immunotherapy of adult brain tumors is likely relevant to the pediatric population and further validation in multicenter pediatric brain tumor peptide-based vaccine studies is warranted.

The Burden of Ionizing Radiation Studies in Children with Ventricular Shunts.

OBJECTIVES: To quantify the number of shunt-related imaging studies that patients with ventricular shunts undergo and to calculate the proportion of computed tomography (CT) scans associated with a surgical intervention. STUDY DESIGN: Retrospective longitudinal cohort analysis of patients up to age 22 years with a shunt placed January 2002 through December 2003 at a pediatric hospital. Primary outcome was the number of head CT scans, shunt series radiograph, skull radiographs, nuclear medicine, and brain magnetic resonance imaging studies for 10 years following shunt placement. Secondary outcome was surgical interventions performed within 7 days of a head CT. Descriptive statistics were used for analysis. RESULTS: Patients (n = 130) followed over 10 years comprised the study cohort. The most common reasons for shunt placement were congenital hydrocephalus (30%), obstructive hydrocephalus (19%), and atraumatic hemorrhage (18%), and 97% of shunts were ventriculoperitoneal. Patients underwent a median of 8.5 head CTs, 3.0 shunt series radiographs, 1.0 skull radiographs, 0 nuclear medicine studies, and 1.0 brain magnetic resonance imaging scans over the 10 years following shunt placement. The frequency of head CT scans was greatest in the first year after shunt placement (median 2.0 CTs). Of 1411 head CTs in the cohort, 237 resulted in surgical intervention within 7 days (17%, 95% CI 15%-19%). CONCLUSIONS: Children with ventricular shunts have been exposed to large numbers of imaging studies that deliver radiation and most do not result in a surgical procedure. This suggests a need to improve the process of evaluating for ventricular shunt malfunction and minimize radiation exposure.

CNS and spinal tumors.

Primary CNS tumors consist of a diverse group of neoplasms originating from various cell types in the CNS. Brain tumors are the most common solid malignancy in children under the age of 15 years and the second leading cause of cancer death after leukemia. The most common brain neoplasms in children differ consistently from those in older age groups. Pediatric brain tumors demonstrate distinct patterns of occurrence and biologic behavior according to sex, age, and race. This chapter highlights the imaging features of the most common tumors that affect the child's CNS (brain and spinal cord).

Evolution of CT imaging features of carotid atherosclerotic plaques in a 1-year prospective cohort study.

PURPOSE: The purpose of this study was to identify imaging markers and clinical risk factors that significantly predict the evolution of computed tomography (CT) imaging features of carotid artery atherosclerotic disease over a 1-year period. METHODS: Our prospective study involved 120 consecutive patients undergoing emergent CT evaluation for symptoms of acute stroke. These patients were asked to consent to a follow-up CT exam in 1 year. To evaluate for atherosclerotic plaque, both at baseline and on follow-up, we employed a comprehensive computed tomography angiography (CTA) protocol that captured the carotid, vertebral, aortic, and coronary arteries. To further evaluate carotid artery plaque components, we used an automated classifier computer algorithm that distinguishes among the histological components of the carotid artery wall (lipids, calcium, fibrous tissue) based on appropriate thresholds of CT density. Baseline values of carotid imaging features and clinical variables were assessed for their ability to significantly predict changes in these imaging features over 1 year. RESULTS: Of these 120 consecutive patients, 17 received both a baseline and a follow-up CTA exam. Wall volume increased more when the largest lipid cluster was located close to the lumen (coefficient -7.61, -13.83 to -1.40, P = .016). The volume of lipid increased with age (coefficient .36, .21 to .50, P = .000), in smokers (coefficient 8.89, 6.82 to 10.95, P = .000) and when fewer lipid clusters were present at baseline (coefficient -0.11, -0.17 to -.04, P = .001). The volume of calcium increased with greater volume of lipid at baseline (coefficient .35, .02 to .68, P = .035) and in patients on statins (coefficient 4.79, 1.73 to 7.86, P = .002). CONCLUSIONS: There are a number of imaging markers and risk factors that significantly predict the evolution of CT imaging features of carotid artery atherosclerotic disease over a 1-year period.

Carotid atherosclerosis does not predict coronary, vertebral, or aortic atherosclerosis in patients with acute stroke symptoms.

BACKGROUND AND PURPOSE: The purpose of this study was to determine whether significant atherosclerotic disease in the carotid arteries predicts significant atherosclerotic disease in the coronary arteries, vertebral arteries, or aorta in patients with symptoms of acute ischemic stroke. METHODS: Atherosclerotic disease was imaged using CT angiography in a prospective study of 120 consecutive patients undergoing emergent CT evaluation for symptoms of stroke. Using a comprehensive CT angiography protocol that captured the carotid arteries, coronary arteries, vertebral arteries, and aorta, we evaluated these arteries for the presence and severity of atherosclerotic disease. Significant atherosclerotic disease was defined as >50% stenosis in the carotid, coronary, and vertebral arteries, or >or=4 mm thickness and encroaching in the aorta. Presence of any and significant atherosclerotic disease was compared in the different types of arteries assessed. RESULTS: Of these 120 patients, 79 had CT angiography examinations of adequate image quality and were evaluated in this study. Of these 79 patients, 33 had significant atherosclerotic disease. In 26 of these 33 patients (79%), significant disease was isolated to 1 type of artery, most often to the coronary arteries (N=14; 54%). Nonsignificant atherosclerotic disease was more systemic and involved multiple arteries. CONCLUSIONS: Significant atherosclerotic disease in the carotid arteries does not predict significant atherosclerotic disease in the coronary arteries, vertebral arteries, or aorta in patients with symptoms of acute ischemic stroke. Significant atherosclerotic disease is most often isolated to 1 type of artery in these patients, whereas nonsignificant atherosclerotic disease tends to be more systemic.

Identification of residual ischemia, infarction, and microvascular impairment in revascularized myocardial infarction using 64-slice MDCT.

This study aimed to assess the potential of 64-slice MDCT in characterizing revascularized infarcted myocardium at the cellular and microvascular levels. Pigs (n = 7) underwent 2 h left anterior descending coronary artery occlusion/reperfusion. In acute (2-4 h) and subacute (1 week) infarction, first-pass perfusion (FPP) (1 ml/kg of 300 mg/ml Omnipaque) was performed using a cine (rotation time 60 s/bpm) non-ECG gated sequence (mAS/kV = 100/120). Delayed contrast enhanced images (DE) (mAS/kV = 650/120) were acquired every 2 min for 10 min to determine the kinetics of Omnipaque and to define infarcted myocardium and microvascular impairment (representing microvascular obstruction and/or no- or low-reflow phenomenon). Maximum upslope, maximum attenuation and time to the peak were measured from FPP plots. 2,3,5-Triphenyltetrazolium-chloride (TTC) was used to define true infarction in the excised hearts. Hyperenhanced myocardium on DE was measured and compared with TTC. The contrast media caused minor beam hardening and X-ray scatter on FPP. The above-mentioned perfusion parameters significantly differed between remote and acute infarction. Infarcted myocardium showed two patterns of enhancement on DE, hyperenhanced rim representing the perfused infarction and hypoenhanced core representing a microvascular impaired region, with significantly different attenuation. The extent of infarction on DE-MDCT decreased over the course of 1 week and did not differ from TTC. Post-processed FPP semi-quantitative images showed a decline in myocardial blood volume and flow in acute revascularized infarction. In conclusion, modern MDCT has the potential to identify residual ischemia on FPP and microvascular impairment and infarction on DE images.

Implicações do fumo na gustação e na olfação: revisando o tema / Implications of Smoke Habit in Gustation and in Olfaction: reviewing the theme

Entre os diversos malefícios causados pelo tabagismo, os efeitos na gustação e na olfação não têm sido abordados pela literatura especializada nacional. Realizou-se um estudo de revisão sobre o tema. Há um predomínio de estudos que se dedicam à investigação da gustação. A exposição ao fumo parece alterar significativamente os dois sistemas quimiorreceptores. A capacidade gustativa está comprometida, quanto à percepção de substâncias salgadas, amargas e doces-principalmente as duas últimas -, bem como à impressão hedônica global (prazer). Dessa forma, a preferência alimentar pode variar. Já na olfação, há alterações ultraestruturais no epitélio, perda na habilidade de identificação de odores (hiposmia) e sensação de queimação e dor na mucosa. Talvez com o esclarecimento da importância desses dois sistemas sensórios e de suas patologias, possam ser efetuados novas revisões e estudos sobre o tema em nosso meio.

Among the variety of general health smoking habit consequences, the effects on gustation and on olfacion have not been reported in the national specialized literature. We did a review study about the issue. There is a predominance of study inquirements on gustation. The smoking habit seems to affect both sensory systems. The gustatory capacity is compromised by a reduction in taste sensibility to salty, bitter and sweet substances (specially the last two), as well by a diminish global hedonic impression (pleasure). Therefore, alimentary preferences may change in smokers. The olfaction is compromised by ultra-estrucutral epithelial alterations. The smell identification ability is reduced (hyposmia), and a sensation of burn and pain on the mucosa is also established. The importance of understanding both sensory systems and their pathology suggests new study requirements among our academic staff.

Drogas antiiflamatórias näo esteroidais e hemorragia digestiva alta / Non steroidal antininflamatory drugs(NSAIDs) and upper gastrointestinal bleeding

Pesquisas têm mostrado os efeitos adversos no sistema gastrintestinal, principalmente nos idosos, entre os usuários de antiinflamatórios, que, por sua vez, têm sido utilizados indiscriminadamente e de maneira crescente. No presente estudo observa-se que em 30 por cento das hemorragias digestivas altas existe referência ao antiinflamatório prévio, geralmente em uso regular, ou seja, maior que duas vezes na semana (79,4 por cento dos casos). Lesoes gástricas (erosoes e/ou úlceras) e erosoes duodenais foram as alteraçoes mais freqüentemente encontradas nos usuários de antiinflamatórios, assim como a presença de mais de uma lesao à endoscopia, enquanto varizes de esôfago foram mais freqüentes no grupo nao-usuário de antiinflamatórios. Variáveis como fumo e álcool foram significativamente mais freqüentes entre os usuários de antiinflamatórios com 60 anos ou menos.