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1.
Transfusion ; 63(4): 839-848, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36811164

RESUMO

BACKGROUND: The optimal method of postgraduate transfusion medicine (TM) education remains understudied. One novel approach is Transfusion Camp, a longitudinal 5-day program that delivers TM education to Canadian and international trainees. The purpose of this study was to determine the self-reported impact of Transfusion Camp on trainee clinical practice. STUDY DESIGN AND METHODS: A retrospective analysis of anonymous survey evaluations from Transfusion Camp trainees over three academic years (2018-2021) was conducted. Trainees were asked, "Have you applied any of your learning from Transfusion Camp into your clinical practice?". Through an iterative process, responses were categorized into topics according to program learning objectives. The primary outcome was the rate of self-reported impact of Transfusion Camp on clinical practice. Secondary outcomes were to determine impact based on specialty and postgraduate year (PGY). RESULTS: Survey response rate was 22%-32% over three academic years. Of 757 survey responses, 68% of respondents indicated that Transfusion Camp had an impact on their practice, increasing to 83% on day 5. The most frequent areas of impact included transfusion indications (45%) and transfusion risk management (27%). Impact increased as PGY increased with 75% of PGY-4+ trainees reporting impact. In multivariable analysis, the impact of specialty and PGY varied depending on the objective. DISCUSSION: The majority of trainees report applying learnings from Transfusion Camp to their clinical practice with variations based on PGY and specialty. These findings support Transfusion Camp as an effective means of TM education and help identify high-yield areas and gaps for future curriculum planning.


Assuntos
Internato e Residência , Humanos , Autorrelato , Estudos Retrospectivos , Canadá , Educação de Pós-Graduação em Medicina , Currículo , Competência Clínica
2.
Breast J ; 2023: 2794603, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37881237

RESUMO

Background: Breast density is an important risk factor for breast cancer and is known to be associated with characteristics such as age, race, and hormone levels; however, it is unclear what factors contribute to changes in breast density in postmenopausal women over time. Understanding factors associated with density changes may enable a better understanding of breast cancer risk and facilitate potential strategies for prevention. Methods: This study investigated potential associations between personal factors and changes in mammographic density in a cohort of 3,392 postmenopausal women with no personal history of breast cancer between 2011 and 2017. Self-reported information on demographics, breast and reproductive history, and lifestyle factors, including body mass index (BMI), alcohol intake, smoking, and physical activity, was collected by an electronic intake form, and breast imaging reporting and database system (BI-RADS) mammographic density scores were obtained from electronic medical records. Factors associated with a longitudinal increase or decrease in mammographic density were identified using Fisher's exact test and multivariate conditional logistic regression. Results: 7.9% of women exhibited a longitudinal decrease in mammographic density, 6.7% exhibited an increase, and 85.4% exhibited no change. Longitudinal changes in mammographic density were correlated with age, race/ethnicity, and age at menopause in the univariate analysis. In the multivariate analysis, Asian women were more likely to exhibit a longitudinal increase in mammographic density and less likely to exhibit a decrease compared to White women. On the other hand, obese women were less likely to exhibit an increase and more likely to exhibit a decrease compared to normal weight women. Women who underwent menopause at age 55 years or older were less likely to exhibit a decrease in mammographic density compared to women who underwent menopause at a younger age. Besides obesity, lifestyle factors (alcohol intake, smoking, and physical activity) were not associated with longitudinal changes in mammographic density. Conclusions: The associations we observed between Asian race/obesity and longitudinal changes in BI-RADS density in postmenopausal women are paradoxical in that breast cancer risk is lower in Asian women and higher in obese women. However, the association between later age at menopause and a decreased likelihood of decreasing in BI-RADS density over time is consistent with later age at menopause being a risk factor for breast cancer and suggests a potential relationship between greater cumulative lifetime estrogen exposure and relative stability in breast density after menopause. Our findings support the complexity of the relationships between breast density, BMI, hormone exposure, and breast cancer risk.


Assuntos
Densidade da Mama , Neoplasias da Mama , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias da Mama/diagnóstico , Mamografia/efeitos adversos , Pós-Menopausa , Fatores de Risco , Estrogênios , Obesidade/complicações
3.
Can J Anaesth ; 70(10): 1660-1668, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37537325

RESUMO

PURPOSE: To describe and review the experience of two pediatric intensive care units (PICUs) in Ontario, Canada, adapting and providing care to critically ill adults during the COVID-19 pandemic. CLINICAL FEATURES: At a time of extreme pressure to adult intensive care unit (ICU) capacity, two PICUs provided care to critically ill adults with COVID-19 pneumonia. Substantial yet rapid planning was required to facilitate safe delivery of critical care to adult patients while maintaining PICU services, including thoughtful development of care pathways and patient selection. To prepare clinical staff, several communication strategies, knowledge translation, skill consolidation, and system-adaptation mechanisms were developed. There was iterative adaptation of operational processes, including staffing models, specialist consultation, and the pharmacy. Care provided by the interprofessional teams was reoriented as appropriate to the needs of critically ill adults in close collaboration with adult ICU teams. Forty-one adults were admitted to the two PICUs over a 12-week period. In total, 36 patients (88%) received invasive ventilation, eight patients (20%) were supported with venovenous extracorporeal membrane oxygenation, and six patients (15%) received continuous renal replacement therapy. Four died in the PICU during this period. Feedback from staff included anxiety around reorienting practice to the care of critically ill adults, physical exhaustion, and psychological distress. Importantly, staff also reported a renewed sense of purpose with participation in the program. CONCLUSION: Though challenging, the experience has provided opportunity to enhance collaboration with partner institutions and improve the care of older children and adolescents in the PICU.


RéSUMé: OBJECTIF: Nous avions pour objectif de décrire et examiner l'expérience de deux unités de soins intensifs pédiatriques (USIP) en Ontario, au Canada, qui se sont adaptées et ont fourni des soins aux adultes gravement malades pendant la pandémie de COVID-19. CARACTéRISTIQUES CLINIQUES: À l'époque où la capacité des unités de soins intensifs (USI) pour adultes était extrêmement sollicitée, deux USIP ont prodigué des soins à des adultes gravement malades souffrant de pneumonie liée à la COVID-19. Une planification substantielle mais rapide a été nécessaire pour faciliter la prestation sécuritaire de soins intensifs à une patientèle adulte tout en maintenant les services de l'USIP, y compris l'élaboration réfléchie des trajectoires de soins et la sélection de la patientèle. Pour préparer le personnel clinique, plusieurs stratégies de communication, d'application des connaissances, de consolidation des compétences et de mécanismes d'adaptation du système ont été élaborées. Il y a eu une adaptation progressive des processus opérationnels, y compris des modèles de dotation, des consultations de spécialistes et de la pharmacie. Les soins fournis par les équipes interprofessionnelles ont été réorientés en fonction des besoins des adultes gravement malades en étroite collaboration avec les équipes adultes de soins intensifs. Quarante et une personnes adultes ont été admises dans les deux unités de soins intensifs pédiatriques sur une période de 12 semaines. Au total, 36 adultes (88 %) ont bénéficié d'une ventilation invasive, huit personnes (20 %) ont reçu une oxygénation par membrane extracorporelle veino-veineuse, et six (15 %) ont reçu un traitement substitutif de l'insuffisance rénale en continu. Quatre personnes sont décédées à l'USIP au cours de cette période. Les commentaires du personnel comprenaient de l'anxiété liée à la réorientation de leur pratique vers des soins à des adultes gravement malades, l'épuisement physique et la détresse psychologique. Fait important, le personnel a également signalé un regain de motivation lié à la participation de leur USIP à ce programme. CONCLUSION: Bien que difficile, l'expérience a permis d'améliorer la collaboration avec les établissements partenaires et d'améliorer les soins aux enfants plus âgé·es et aux adolescent·es de l'USIP.


Assuntos
COVID-19 , Criança , Adolescente , Humanos , Adulto , Ontário , Estado Terminal/terapia , Pandemias , Unidades de Terapia Intensiva Pediátrica , Unidades de Terapia Intensiva
4.
IEEE Trans Eng Manag ; 70(8): 2931-2943, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37954189

RESUMO

Hospitals and other healthcare settings use various simulation methods to improve their operations, management, and training. The COVID-19 pandemic, with the resulting necessity for rapid and remote assessment, has highlighted the critical role of modeling and simulation in healthcare, particularly distributed simulation (DS). DS enables integration of heterogeneous simulations to further increase the usability and effectiveness of individual simulations. This article presents a DS system that integrates two different simulations developed for a hospital intensive care unit (ICU) ward dedicated to COVID-19 patients. AnyLogic has been used to develop a simulation model of the ICU ward using agent-based and discrete event modeling methods. This simulation depicts and measures physical contacts between healthcare providers and patients. The Unity platform has been utilized to develop a virtual reality simulation of the ICU environment and operations. The high-level architecture, an IEEE standard for DS, has been used to build a cloud-based DS system by integrating and synchronizing the two simulation platforms. While enhancing the capabilities of both simulations, the DS system can be used for training purposes and assessment of different managerial and operational decisions to minimize contacts and disease transmission in the ICU ward by enabling data exchange between the two simulations.

5.
Can J Anaesth ; 68(2): 235-244, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33174164

RESUMO

PURPOSE: Residency programs need to understand the competencies developed by residents during an intensive care unit (ICU) rotation, so that curricula and assessments maximize residents' learning. The primary study objective was to evaluate the feasibility for training programs and acceptability by residents of conducting a multi-competency assessment during a four-week ICU rotation. METHODS: We conducted a prospective, multicentre observational pilot study in three ICUs. During weeks 1 and 4 of an ICU rotation, we conducted repeated standardized assessments of non-critical care specialty residents' competencies in cognitive reasoning (script concordance test [SCT]), procedural skills (objective structured assessment of technical skills [OSATS]-global rating scale], and communication skills through a written test, two procedural simulations, and a simulated encounter with a "family member". The feasibility outcomes included program costs, the proportion of enrolled residents able to complete at least one three-station assessment during their four-week ICU rotation, and acceptability of the assessment for the trainees. RESULTS: We enrolled 63 (69%) of 91 eligible residents, with 58 (92%) completing at least one assessment. The total cost to conduct 90 assessments was CAD 33,800. The majority of participants agreed that the assessment was fair and that it measured important clinical abilities. For the 32 residents who completed two assessments, the mean (standard deviation) cognitive reasoning and procedural skill scores increased between weeks 1 and 4 [SCT difference, 3.1 (6.5), P = 0.01; OSATS difference for bag-mask ventilation and central line insertion, 0.4 (0.5) and 0.6 (0.8), respectively; both P ≤ 0.001]. Nevertheless, the communication scores did not change significantly. CONCLUSIONS: A monthly multi-competency assessment for specialty residents rotating in the ICU is likely feasible for most programs with appropriate resources, and generally acceptable for residents. Specialty residents' cognitive reasoning and procedural skills may improve during a four-week ICU rotation, whereas communication skills may not.


RéSUMé: OBJECTIF: Afin que les programmes de formation et les évaluations maximisent les apprentissages des résidents, les programmes de résidence doivent comprendre quelles compétences sont développées par les résidents pendant un stage à l'unité de soins intensifs (USI). L'objectif principal de cette étude était d'évaluer la faisabilité pour les programmes de formation et l'acceptabilité par les résidents de réaliser une évaluation multi-compétences pendant un stage de quatre semaines à l'USI. MéTHODE: Nous avons réalisé une étude pilote observationnelle prospective multicentrique dans trois USI. Pendant les semaines 1 et 4 du stage à l'USI, nous avons mené des évaluations standardisées répétées des compétences des résidents non inscrits dans une spécialisation en soins intensifs en matière de raisonnement cognitif (test de concordance de script [SCT]), d'habiletés procédurales (évaluation objective structurée des compétences techniques [OSATS] - échelle d'évaluation globale), et d'habiletés de communication via un examen écrit, deux simulations d'intervention, et une rencontre simulée avec un « membre de la famille ¼. Les critères de faisabilité comprenaient les coûts du programme d'évaluation, la proportion de résidents inscrits capables de compléter au moins une évaluation en trois stations au cours de leur stage de quatre semaines à l'USI, et l'acceptabilité de l'évaluation par les résidents. RéSULTATS: Nous avons recruté 63 (69 %) des 91 résidents éligibles, et 58 (92 %) ont complété au moins une évaluation. Le coût total pour réaliser 90 évaluations était de 33 800 CAD. La majorité des participants étaient d'accord que l'évaluation était équitable et qu'elle mesurait d'importantes habiletés cliniques. Chez les 32 résidents ayant complété deux évaluations, les scores moyens (écart type) en matière de raisonnement cognitif et d'habiletés techniques ont augmenté entre les semaines 1 et 4 : différence au SCT, 3,1 (6,5), P = 0,0; différence à l'OSATS pour la ventilation au masque et l'installation d'une voie centrale, 0,4 (0,5) et 0,6 (0,8), respectivement; tous deux P ≤ 0,001. Toutefois, les scores en matière de communication n'ont pas changé de manière significative. CONCLUSION: Une évaluation multi-compétences mensuelle des résidents en spécialisation faisant un stage à l'USI est probablement réalisable dans la plupart des programmes disposant des ressources nécessaires, et elle est généralement acceptable pour les résidents. Le raisonnement cognitif et les habiletés techniques des résidents pourraient s'améliorer pendant un stage de quatre semaines à l'USI, alors que leurs compétences de communication pourraient demeurer inchangées.


Assuntos
Internato e Residência , Competência Clínica , Comunicação , Currículo , Humanos , Unidades de Terapia Intensiva , Estudos Prospectivos
6.
Hemoglobin ; 45(4): 269-273, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34749584

RESUMO

Fat embolism syndrome (FES) is a rare condition that can occur as a complication of sickle cell disease. We describe a case of a patient with sickle cell disease (homozygous Hb S or HBB: c.20A>T) presenting with initial signs and symptoms consistent with a vaso-occlusive crisis (VOC). Within 24 hours, the patient developed evidence of coagulopathy, multi organ failure and a reduced level of consciousness (LOC) prompting intubation. A diagnosis of FES was made on the basis of the patient's clinical presentation, in conjunction with magnetic resonance imaging (MRI) of the brain revealing innumerable tiny foci of restricted diffusion, intracytoplasmic microvesicular fat on Sudan Red staining of bronchoalveolar lavage samples and evidence of a pulmonary shunt on echocardiogram bubble study. Red blood cell (RBC) exchange transfusion was initiated 3 days following initial presentation and no further exchange transfusions were needed on the basis of subsequent Hb S (HBB: c.20A>T) levels. The LOC gradually improved and the patient was extubated 12 days following presentation. Neurological improvement was slow, with mild cognitive impairment initially evident at 3 months and no cognitive or neurological deficits remaining within 6 months of admission. This case highlights the importance of understanding the pathophysiology and clinical presentation of FES, as early exchange transfusion may improve survival in patients with sickle cell disease and FES.


Assuntos
Anemia Falciforme , Embolia Gordurosa , Anemia Falciforme/complicações , Embolia Gordurosa/diagnóstico , Embolia Gordurosa/etiologia , Humanos , Imageamento por Ressonância Magnética
7.
Anal Bioanal Chem ; 412(24): 6611-6624, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32666141

RESUMO

Glucose and lactate provide energy for cellular function in the brain and serve as an important carbon source in the synthesis of a variety of biomolecules. Thus, there is a critical need to quantitatively monitor these molecules in situ on a time scale commensurate with neuronal function. In this work, carbon-fiber microbiosensors were coupled with fast-scan cyclic voltammetry to monitor glucose and lactate fluctuations at a discrete site within rat striatum upon electrical stimulation of the midbrain projection to the region. Systematic variation of stimulation parameters revealed the distinct dynamics by which glucose and lactate responded to the metabolic demand of synaptic function. Immediately upon stimulation, extracellular glucose and lactate availability rapidly increased. If stimulation was sufficiently intense, concentrations then immediately fell below baseline in response to incurred metabolic demand. The dynamics were dependent on stimulation frequency, such that more robust fluctuations were observed when the same number of pulses was delivered at a higher frequency. The rates at which glucose was supplied to, and depleted from, the local recording region were dependent on stimulation intensity, and glucose dynamics led those of lactate in response to the most substantial stimulations. Glucose fluctuated over a larger concentration range than lactate as stimulation duration increased, and glucose fell further from baseline concentrations. These real-time measurements provide an unprecedented direct comparison of glucose and lactate dynamics in response to metabolic demand elicited by neuronal activation. Graphical abstract.


Assuntos
Corpo Estriado/metabolismo , Estimulação Elétrica , Glucose/metabolismo , Ácido Láctico/metabolismo , Mesencéfalo/metabolismo , Animais , Técnicas Biossensoriais , Corpo Estriado/química , Técnicas Eletroquímicas , Glucose/análise , Ácido Láctico/análise , Masculino , Mesencéfalo/química , Microeletrodos , Ratos , Ratos Sprague-Dawley
8.
Med Educ ; 54(12): 1120-1128, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32614455

RESUMO

CONTEXT: Research in workplace learning has emphasised trainees' active role in their education. By focusing on how trainees fine-tune their strategic learning, theories of self-regulated learning (SRL) offer a unique lens to study workplace learning. To date, studies of SRL in the workplace tend to focus on listing the factors affecting learning, rather than on the specific mechanisms trainees use to regulate their goal-directed activities. To inform the design of workplace learning interventions that better support SRL, we asked: How do residents navigate their exposure to and experience performing invasive procedures in intensive care units? METHODS: In two academic hospitals, we conducted post-call debriefs with residents coming off shift and later sought their elaborated perspectives via semi-structured interviews. We used a constant comparative methodology to analyse the data, to iteratively refine data collection, and to inform abductive coding of the data, using SRL principles as sensitising concepts. RESULTS: We completed 29 debriefs and nine interviews with 24 trainees. Participants described specific mechanisms: identifying, creating, avoiding, missing and competing for opportunities to perform invasive procedures. While using these mechanisms to engage with procedures (or not), participants reported: distinguishing trajectories (i.e. becoming attuned to task-relevant factors), navigating trajectories (i.e. creating and interacting with opportunities to perform procedures), and co-constructing trajectories with their peers, supervisors and interprofessional team members. CONCLUSIONS: We identified specific SRL mechanisms trainees used to distinguish and navigate possible learning trajectories. We also confirmed previous findings, including that trainees become attuned to interactions between personal, behavioural and environmental factors (SRL theory), and that their resulting learning behaviours are constrained and guided by interactions with peers, supervisors and colleagues (workplace learning theory). Making learning trajectories explicit for clinician teachers may help them support trainees in prioritising certain trajectories, in progressing along each trajectory, and in co-constructing their plans for navigating them.


Assuntos
Internato e Residência , Aprendizagem , Competência Clínica , Humanos , Motivação , Local de Trabalho
9.
N Engl J Med ; 374(19): 1831-41, 2016 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-27168433

RESUMO

BACKGROUND: Few resources are available to support caregivers of patients who have survived critical illness; consequently, the caregivers' own health may suffer. We studied caregiver and patient characteristics to determine which characteristics were associated with caregivers' health outcomes during the first year after patient discharge from an intensive care unit (ICU). METHODS: We prospectively enrolled 280 caregivers of patients who had received 7 or more days of mechanical ventilation in an ICU. Using hospital data and self-administered questionnaires, we collected information on caregiver and patient characteristics, including caregiver depressive symptoms, psychological well-being, health-related quality of life, sense of control over life, and effect of providing care on other activities. Assessments occurred 7 days and 3, 6, and 12 months after ICU discharge. RESULTS: The caregivers' mean age was 53 years, 70% were women, and 61% were caring for a spouse. A large percentage of caregivers (67% initially and 43% at 1 year) reported high levels of depressive symptoms. Depressive symptoms decreased at least partially with time in 84% of the caregivers but did not in 16%. Variables that were significantly associated with worse mental health outcomes in caregivers were younger age, greater effect of patient care on other activities, less social support, less sense of control over life, and less personal growth. No patient variables were consistently associated with caregiver outcomes over time. CONCLUSIONS: In this study, most caregivers of critically ill patients reported high levels of depressive symptoms, which commonly persisted up to 1 year and did not decrease in some caregivers. (Funded by the Canadian Institutes of Health Research and others; ClinicalTrials.gov number, NCT00896220.).


Assuntos
Cuidadores/psicologia , Estado Terminal/enfermagem , Depressão/etiologia , Família/psicologia , Adulto , Idoso , Depressão/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Qualidade de Vida , Estresse Psicológico
10.
Transfusion ; 59(6): 2141-2149, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30946497

RESUMO

BACKGROUND: The optimal method of providing transfusion medicine (TM) education has not been determined. Transfusion Camp was established in 2012 at the University of Toronto as a centrally delivered TM education program for postgraduate trainees. The impact of Transfusion Camp on knowledge, attitudes, and self-reported behavior was evaluated. METHODS: Didactic lectures (delivered locally, by webinar, or recorded) and locally facilitated team-based learning seminars were delivered over 5 days during the academic year to 8 sites: 7 in Canada and 1 in the United Kingdom. Knowledge assessment using a validated 20-question multiple-choice exam was conducted before and after Transfusion Camp. Attitudes and self-reported behavior were collected through a survey. RESULTS: Over 2 academic years (July 2016 to June 2018), 390 trainees from 16 different specialties (predominantly anesthesia, 41%; hematology, 14%; and critical care, 7%) attended at least 1 day of Transfusion Camp. The mean pretest score was 10.3 of 20 (±2.9; n = 286) compared with posttest score of 13.0 (±2.8; n = 194; p < 0.0001). Lower pretest score and greater attendance (4-5 days compared with 1-3 days) were associated with larger improvement in posttest score; delivery format, specialty, and postgraduate year were not. Trainees reported an improvement in self-rated abilities to manage TM scenarios; 95% rated TM knowledge as very or extremely important in providing patient care; and 81% indicated that they had applied learning from Transfusion Camp into clinical practice. CONCLUSIONS: Transfusion Camp increased TM knowledge, fostered a positive attitude toward TM, and enabled a self-reported positive impact on transfusion practice in postgraduate trainees. It is a novel and scalable approach to delivering TM education.


Assuntos
Transfusão de Sangue , Currículo , Hematologia/educação , Internato e Residência/métodos , Medicina Transfusional/educação , Atitude , Transfusão de Sangue/métodos , Transfusão de Sangue/normas , Canadá , Currículo/normas , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Internato e Residência/organização & administração , Medicina , Avaliação de Programas e Projetos de Saúde , Estudos Prospectivos , Autorrelato , Estudantes de Medicina/psicologia
11.
Anal Chem ; 90(21): 12994-12999, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30295022

RESUMO

Recent studies have described a role for lactate in brain energy metabolism and energy formation, challenging the conventional view that glucose is the principle energy source for brain function. To date, lactate dynamics in the brain are largely unknown, limiting insight into function. We addressed this by developing and characterizing a lactate oxidase-modified carbon-fiber microelectrode coupled with fast-scan cyclic voltammetry. This new tool boasts a sensitivity for lactate of 22 ± 1 nA·mM-1 and LOD of 7.0 ± 0.7 µM. The approach has enabled detection of rapid lactate fluctuations with unprecedented spatiotemporal resolution as well as excellent stability, selectivity, and sensitivity. The technology was characterized both in vitro and in vivo at discrete recording sites in rat striatum. We provide evidence that striatal lactate availability increases biphasically in response to electrical stimulation of the dopaminergic midbrain in the anesthetized rat. This new tool for real-time detection of lactate dynamics promises to improve understanding of how lactate availability underscores neuronal function and dysfunction.


Assuntos
Técnicas Biossensoriais/métodos , Fibra de Carbono/química , Técnicas Eletroquímicas/métodos , Ácido Láctico/análise , Neostriado/metabolismo , Animais , Técnicas Eletroquímicas/instrumentação , Enzimas Imobilizadas/química , Limite de Detecção , Masculino , Microeletrodos , Oxigenases de Função Mista/química , Ratos Sprague-Dawley , Sensibilidade e Especificidade
12.
Chemphyschem ; 19(10): 1197-1204, 2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-29316144

RESUMO

Electrochemical monitoring of non-electroactive species requires a biosensor that is stable and selective, with sensitivity to physiological concentrations of targeted analytes. We have combined glucose oxidase-modified carbon-fiber microelectrodes with fast-scan cyclic voltammetry for real-time measurements of glucose fluctuations in brain tissue. Work presented herein quantitatively compares three approaches to enzyme immobilization on the microelectrode surface-physical adsorption, hydrogel entrapment, and entrapment in electrospun nanofibers. The data suggest that each of these methods can be used to create functional microbiosensors. Immobilization of glucose oxidase by physical adsorption generates a biosensor with poor sensitivity to glucose and unstable performance. Entrapment of glucose oxidase in poly(vinyl alcohol) nanofibers generates microbiosensors that are effective for glucose measurements over a large linear range, and that may be particularly useful when targeting glucose concentrations in excess of 3 mm, such as in blood. Hydrogel entrapment is the most effective in terms of sensitivity and stability. These microbiosensors can be used for simultaneous monitoring of glucose and dopamine in real time. The findings outlined herein should be applicable to other oxidase enzymes, and thus they are broadly important for the development of new tools for real-time measurements of fluctuating molecules that are not inherently electroactive.


Assuntos
Técnicas Biossensoriais , Carbono/química , Técnicas Eletroquímicas , Glucose Oxidase/metabolismo , Glucose/análise , Animais , Enzimas Imobilizadas , Masculino , Microeletrodos , Ratos , Ratos Sprague-Dawley , Fatores de Tempo
13.
Can J Anaesth ; 65(3): 272-279, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29256064

RESUMO

PURPOSE: Flexible bronchoscopy with bronchoalveolar lavage (BAL) is commonly performed in immunocompromised patients. Nevertheless, it remains unclear whether bronchoscopy with BAL leads to changes in medical management or is associated with procedural complications among critically ill acute leukemia (AL) patients. METHODS: We evaluated 71 AL patients who underwent diagnostic bronchoscopy with BAL in the intensive care unit (ICU) between 1 January 2007 and 31 December 2012. We recorded baseline characteristics, vital signs (before, during, and after the procedure), changes in medical management following the procedure, and procedural complications. Using a multivariable logistic regression model, we explored the relationship between patient characteristics and whether bronchoscopy changed management or caused complications. Patient characteristics included as predictors in the regression model were age, sex, immunosuppression status (those undergoing active chemotherapy), and the Acute Physiology And Chronic Health Evaluation II score. RESULTS: The most common indication for ICU admission was respiratory failure (51 patients, 72%), followed by sepsis (14 patients, 20%). Overall, the results obtained from bronchoscopy with BAL were associated with a change in management in 32 patients (45%), most commonly a change in antimicrobial therapy as a result of an infectious pathogen being identified (17 patients, 24%). Complications were documented in nine patients (13%) and included post-procedural hypoxia (six patients, 8%), the need for intubation (one patient, 9% of non-intubated patients), and tracheal perforation (one patient, 1%). No clinically significant changes in patient vital signs were observed during or immediately following the procedure. Patient characteristics did not predict whether bronchoscopy was associated with changes in medical management or procedural complications in multivariable analyses. CONCLUSIONS: Flexible bronchoscopy with BAL is relatively safe and helps to guide medical management among patients with AL admitted to the ICU.


Assuntos
Lavagem Broncoalveolar/métodos , Broncoscopia/métodos , Unidades de Terapia Intensiva , Leucemia/terapia , Broncoscopia/efeitos adversos , Broncoscopia/instrumentação , Estudos de Coortes , Estado Terminal , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Insuficiência Respiratória/epidemiologia , Estudos Retrospectivos , Sepse/epidemiologia
14.
J Intensive Care Med ; : 885066617690725, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-28142306

RESUMO

INTRODUCTION: Noninvasive ventilation (NIV) is commonly used as first-line therapy for immunocompromised patients with acute respiratory failure. However, it may not be appropriate for all patients, as failure of NIV and delayed endotracheal intubation (ETI) may increase mortality. We report our center's experience and outcomes for patients with active hematologic malignancy (HM) treated with NIV. METHODS: We conducted a retrospective study of consecutive patients with HM who were admitted to the intensive care unit (ICU) of Mount Sinai Hospital for acute respiratory failure between January 1, 2010, and May 31, 2015, and were initially treated with NIV. We compared the characteristics of patients who were successfully treated with NIV and avoided intubation and those who failed NIV. RESULTS: Seventy-nine patients (mean age 56 ± 14 years, mean Acute Physiology and Chronic Health Evaluation II score 27 ± 5) with HM were treated with NIV for acute respiratory failure. The etiology of respiratory failure was multifactorial in 31 (39%) patients, with features of pneumonia in 61 (77%) patients, severe sepsis or septic shock in 33 (42%) patients, and pulmonary edema in 24 (30%) patients. The majority of patients were admitted with acute leukemia (n = 60, 76%), 8 (10%) with lymphoma, and 11 (14%) with chronic leukemia, multiple myeloma, or myelodysplastic syndrome. Of the 79 patients treated with NIV, 44 (56%) failed NIV and required ETI, 7 (9%) had a do-not-intubate (DNI) order and died, and 28 (35%) avoided ETI. Compared with patients who avoided ETI, those who failed NIV or had a DNI order and died were more likely to have acute leukemia (84% vs 61%; P = .02) and at baseline had higher Paco2 (39 vs 30; P = .038), higher fraction of inspired oxygen (Fio2) requirements (0.6 vs 0.4; P = .002), and more vasopressor use (31% vs 11%; P = .059). The ICU mortality was 42%; 3-month mortality was 57% overall and was significantly lower in the NIV success patients compared with the NIV failure group (21% vs 74%; P < .001). CONCLUSION: Two-thirds of patients with HM and respiratory failure failed NIV and required ETI, and had high subsequent mortality. Patients who failed NIV had higher Paco2, higher Fio2, and a trend toward more vasopressor use.

15.
Palliat Med ; 31(2): 130-139, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27307057

RESUMO

BACKGROUND: Communication skills are important when discussing goals of care and resuscitation. Few studies have evaluated the effectiveness of standardized patients for teaching medical trainees to communicate about goals of care. OBJECTIVE: To determine whether standardized patient simulation offers benefit over didactic sessions alone for improving skill and comfort discussing goals of care. DESIGN AND INTERVENTION: Single-blind, randomized, controlled trial of didactic teaching plus standardized patient simulation versus didactic teaching alone. PARTICIPANTS: First-year internal medicine residents. MAIN MEASURES: Changes in communication comfort and skill between baseline and 2 months post-training assessed using the Consultation and Relational Empathy measure. KEY RESULTS: We enrolled 94 residents over a 2-year period. Both groups reported a significant improvement in comfort when discussing goals of care with patients. There was no difference in Consultation and Relational Empathy scores following the workshop ( p = 0.79). The intervention group showed a significant increase in Consultation and Relational Empathy scores post-workshop compared with pre-workshop (35.0 vs 31.7, respectively; p = 0.048), whereas there was no improvement in Consultation and Relational Empathy scores in the control group (35.6 vs 36.0; p = 0.4). However, when the results were adjusted for baseline differences in Consultation and Relational Empathy scores in a multivariable regression analysis, group assignment was not associated with an improvement in Consultation and Relational Empathy score. Improvement in comfort scores and perception of benefit were not associated with improvements in Consultation and Relational Empathy scores. CONCLUSION: Simulation training may improve communication skill and comfort more than didactic training alone, but there were important confounders in this study and further studies are needed to determine whether simulation is better than didactic training for this purpose.


Assuntos
Comunicação , Educação Profissionalizante/métodos , Internato e Residência/métodos , Planejamento de Assistência ao Paciente , Simulação de Paciente , Competência Profissional/normas , Ressuscitação , Adulto , Atitude do Pessoal de Saúde , Competência Clínica , Educação Médica , Empatia , Feminino , Humanos , Masculino , Estudos Prospectivos , Análise de Regressão , Ensino
16.
Am J Respir Crit Care Med ; 194(7): 831-844, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26974173

RESUMO

RATIONALE: Disability risk groups and 1-year outcome after greater than or equal to 7 days of mechanical ventilation (MV) in medical/surgical intensive care unit (ICU) patients are unknown and may inform education, prognostication, rehabilitation, and study design. OBJECTIVES: To stratify patients for post-ICU disability and recovery to 1 year after critical illness. METHODS: We evaluated a multicenter cohort of 391 medical/surgical ICU patients who received greater than or equal to 1 week of MV at 7 days and 3, 6, and 12 months after ICU discharge. Disability risk groups were identified using recursive partitioning modeling. MEASUREMENTS AND MAIN RESULTS: The 7-day post-ICU Functional Independence Measure (FIM) determined the recovery trajectory to 1-year after ICU discharge and was an independent risk factor for 1-year mortality. The 7-day post-ICU FIM was predicted by age and ICU length of stay. By 2 weeks of MV, ICU patients could be stratified into four disability groups characterized by increasing risk for post ICU disability, ICU and post-ICU healthcare use, and disposition. Patients less than 42 years with ICU length of stay less than 2 weeks had the best function and fewest deaths at 1 year compared with patients greater than 66 years with ICU length of stay greater than 2 weeks who sustained the worst disability and 40% 1-year mortality. Depressive symptoms (17%) and post-traumatic stress disorder (18%) persisted at 1 year. CONCLUSIONS: ICU survivors of greater than or equal to 1 week of MV may be stratified into four disability groups based on age and ICU length of stay. These groups determine 1-year recovery and healthcare use and are independent of admitting diagnosis and illness severity. Clinical trial registered with www.clinicaltrials.gov (NCT 00896220).

17.
Anal Chem ; 88(16): 8129-36, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27441547

RESUMO

L-DOPA has been the gold standard for symptomatic treatment of Parkinson's disease. However, its efficacy wanes over time as motor complications develop. Very little is known about how L-DOPA therapy affects the dynamics of fluctuating dopamine concentrations in the striatum on a rapid time scale (seconds). Electrochemical studies investigating the effects of L-DOPA treatment on electrically evoked dopamine release have reported conflicting results with significant variability. We hypothesize that the uncertainty in the electrochemical data is largely due to electrode fouling caused by polymerization of L-DOPA and endogenous catecholamines on the electrode surface. Thus, we have systematically optimized the procedure for fabricating cylindrical, Nafion-coated, carbon-fiber microelectrodes. This has enabled rapid and reliable detection of L-DOPA's effects on striatal dopamine signaling in intact rat brain using fast-scan cyclic voltammetry. An acute dose of 5 mg/kg L-DOPA had no significant effect on dopamine dynamics, demonstrating the highly efficient regulatory mechanisms at work in the intact brain. In contrast, administration of 200 mg/kg L-DOPA significantly increased the amplitude of evoked dopamine release by ∼200%. Overall, this work describes a reliable tool that allows a better measure of L-DOPA augmented dopamine release in vivo, measured using fast-scan cyclic voltammetry. It provides a methodology that improves the stability and performance of the carbon-fiber microelectrode when studying the molecular mechanisms underlying L-DOPA therapy and also promises to benefit a wide variety of studies because Nafion is so commonly used in electroanalytical chemistry.


Assuntos
Carbono/química , Dopamina/análise , Técnicas Eletroquímicas , Levodopa/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Fibra de Carbono , Eletrodos Implantados , Potenciais Evocados/efeitos dos fármacos , Masculino , Microeletrodos , Doença de Parkinson/metabolismo , Doença de Parkinson/patologia , Ratos , Ratos Sprague-Dawley
18.
Int J Neuropsychopharmacol ; 18(2)2014 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-25575584

RESUMO

BACKGROUND: Depression and related disorders are characterized by deficits in behavioral activation, exertion of effort, and other psychomotor/motivational dysfunctions. Depressed patients show alterations in effort-related decision making and a bias towards selection of low effort activities. It has been suggested that animal tests of effort-related decision making could be useful as models of motivational dysfunctions seen in psychopathology. METHODS: Because clinical studies have suggested that inhibition of catecholamine uptake may be a useful strategy for treatment of effort-related motivational symptoms, the present research assessed the ability of bupropion to increase work output in rats responding on a test of effort-related decision-making (ie, a progressive ratio/chow feeding choice task). With this task, rats can choose between working for a preferred food (high-carbohydrate pellets) by lever pressing on a progressive ratio schedule vs obtaining a less preferred laboratory chow that is freely available in the chamber. RESULTS: Bupropion (10.0-40.0 mg/kg intraperitoneal) significantly increased all measures of progressive ratio lever pressing, but decreased chow intake. These effects were greatest in animals with low baseline levels of work output on the progressive ratio schedule. Because accumbens dopamine is implicated in effort-related processes, the effects of bupropion on markers of accumbens dopamine transmission were examined. Bupropion elevated extracellular dopamine levels in accumbens core as measured by microdialysis and increased phosphorylated dopamine and cyclic-AMP related phosphoprotein 32 kDaltons (pDARPP-32) immunoreactivity in a manner consistent with D1 and D2 receptor stimulation. CONCLUSION: The ability of bupropion to increase exertion of effort in instrumental behavior may have implications for the pathophysiology and treatment of effort-related motivational symptoms in humans.


Assuntos
Bupropiona/farmacologia , Comportamento de Escolha/efeitos dos fármacos , Inibidores da Captação de Dopamina/farmacologia , Motivação/efeitos dos fármacos , Psicotrópicos/farmacologia , Esquema de Reforço , Animais , Comportamento de Escolha/fisiologia , Cromatografia Líquida de Alta Pressão , Dopamina/metabolismo , Fosfoproteína 32 Regulada por cAMP e Dopamina/metabolismo , Relação Dose-Resposta a Droga , Alimentos , Imuno-Histoquímica , Masculino , Microdiálise , Motivação/fisiologia , Núcleo Accumbens/efeitos dos fármacos , Núcleo Accumbens/fisiologia , Fosforilação/efeitos dos fármacos , Ratos Sprague-Dawley
19.
Crit Care ; 18(6): 600, 2014 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-25673278

RESUMO

Over the last 10 years, there has been an explosion of literature surrounding sedation management for critically ill patients. The clinical target has moved away from an unconscious and immobile patient toward a goal of light or no sedation and early mobility. The move away from terms such as 'sedation' toward more patient-centered and symptom-based control of pain, anxiety, and agitation makes the management of critically ill patients more individualized and dynamic. Over-sedation has been associated with negative ICU outcomes, including longer durations of mechanical ventilation and lengths of stay, but few studies have been able to associate deep sedation with increased mortality.


Assuntos
Atividades Cotidianas , Unidades de Terapia Intensiva/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Sobreviventes/estatística & dados numéricos , Feminino , Humanos , Masculino
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