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1.
Magn Reson Med ; 87(4): 1938-1951, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34904726

RESUMO

PURPOSE: Restriction spectrum imaging (RSI) decomposes the diffusion-weighted MRI signal into separate components of known apparent diffusion coefficients (ADCs). The number of diffusion components and optimal ADCs for RSI are organ-specific and determined empirically. The purpose of this work was to determine the RSI model for breast tissues. METHODS: The diffusion-weighted MRI signal was described using a linear combination of multiple exponential components. A set of ADC values was estimated to fit voxels in cancer and control ROIs. Later, the signal contributions of each diffusion component were estimated using these fixed ADC values. Relative-fitting residuals and Bayesian information criterion were assessed. Contrast-to-noise ratio between cancer and fibroglandular tissue in RSI-derived signal contribution maps was compared to DCE imaging. RESULTS: A total of 74 women with breast cancer were scanned at 3.0 Tesla MRI. The fitting residuals of conventional ADC and Bayesian information criterion suggest that a 3-component model improves the characterization of the diffusion signal over a biexponential model. Estimated ADCs of triexponential model were D1,3 = 0, D2,3 = 1.5 × 10-3 , and D3,3 = 10.8 × 10-3 mm2 /s. The RSI-derived signal contributions of the slower diffusion components were larger in tumors than in fibroglandular tissues. Further, the contrast-to-noise and specificity at 80% sensitivity of DCE and a subset of RSI-derived maps were equivalent. CONCLUSION: Breast diffusion-weighted MRI signal was best described using a triexponential model. Tumor conspicuity in breast RSI model is comparable to that of DCE without the use of exogenous contrast. These data may be used as differential features between healthy and malignant breast tissues.


Assuntos
Neoplasias da Mama , Imagem de Difusão por Ressonância Magnética , Teorema de Bayes , Mama/diagnóstico por imagem , Mama/patologia , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/patologia , Meios de Contraste , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Sensibilidade e Especificidade
2.
NMR Biomed ; 34(7): e4508, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33738878

RESUMO

Diffusion-weighted MRI (DWI) is an important tool for oncology research, with great clinical potential for the classification and monitoring of breast lesions. The utility of parameters derived from DWI, however, is influenced by specific analysis choices. The purpose of this study was to critically evaluate repeatability and curve-fitting performance of common DWI signal representations, for a prospective cohort of patients with benign breast lesions. Twenty informed, consented patients with confirmed benign breast lesions underwent repeated DWI (3 T) using: sagittal single-shot spin-echo echo planar imaging, bipolar encoding, TR/TE: 11,600/86 ms, FOV: 180 x 180 mm, matrix: 90 x 90, slices: 60 x 2.5 mm, iPAT: GRAPPA 2, fat suppression, and 13 b-values: 0-700 s/mm2 . A phase-reversed scan (b = 0 s/mm2 ) was acquired for distortion correction. Voxel-wise repeat-measures coefficients of variation (CoVs) were derived for monoexponential (apparent diffusion coefficient [ADC]), biexponential (intravoxel incoherent motion: f, D, D*) and stretched exponential (α, DDC) across the parameter histograms for lesion regions of interest (ROIs). Goodness-of-fit for each representation was assessed by Bayesian information criterion. The volume of interest (VOI) definition was repeatable (CoV 13.9%). Within lesions, and across both visits and the cohort, there was no dominant best-fit model, with all representations giving the best fit for a fraction of the voxels. Diffusivity measures from the signal representations (ADC, D, DDC) all showed good repeatability (CoV < 10%), whereas parameters associated with pseudodiffusion (f, D*) performed poorly (CoV > 50%). The stretching exponent α was repeatable (CoV < 12%). This pattern of repeatability was consistent over the central part of the parameter percentiles. Assumptions often made in diffusion studies about analysis choices will influence the detectability of changes, potentially obscuring useful information. No single signal representation prevails within or across lesions, or across repeated visits; parameter robustness is therefore a critical consideration. Our results suggest that stretched exponential representation is more repeatable than biexponential, with pseudodiffusion parameters unlikely to provide clinically useful biomarkers.


Assuntos
Doenças Mamárias/diagnóstico por imagem , Neoplasias da Mama/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/estatística & dados numéricos , Adulto , Teorema de Bayes , Biópsia com Agulha de Grande Calibre , Doenças Mamárias/patologia , Neoplasias da Mama/patologia , Estudos de Coortes , Feminino , Fibroadenoma/patologia , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes
3.
MAGMA ; 33(2): 317-328, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31562584

RESUMO

OBJECTIVES: To investigate the reliability of simultaneous positron emission tomography and magnetic resonance imaging (PET/MRI)-derived biomarkers using semi-automated Gaussian mixture model (GMM) segmentation on PET images, against conventional manual tumor segmentation on dynamic contrast-enhanced (DCE) images. MATERIALS AND METHODS: Twenty-four breast cancer patients underwent PET/MRI (following 18F-fluorodeoxyglucose (18F-FDG) injection) at baseline and during neoadjuvant treatment, yielding 53 data sets (24 untreated, 29 treated). Two-dimensional tumor segmentation was performed manually on DCE-MRI images (manual DCE) and using GMM with corresponding PET images (GMM-PET). Tumor area and mean apparent diffusion coefficient (ADC) derived from both segmentation methods were compared, and spatial overlap between the segmentations was assessed with Dice similarity coefficient and center-of-gravity displacement. RESULTS: No significant differences were observed between mean ADC and tumor area derived from manual DCE segmentation and GMM-PET. There were strong positive correlations for tumor area and ADC derived from manual DCE and GMM-PET for untreated and treated lesions. The mean Dice score for GMM-PET was 0.770 and 0.649 for untreated and treated lesions, respectively. DISCUSSION: Using PET/MRI, tumor area and mean ADC value estimated with a GMM-PET can replicate manual DCE tumor definition from MRI for monitoring neoadjuvant treatment response in breast cancer.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Fluordesoxiglucose F18 , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Adulto , Idoso , Neoplasias da Mama/tratamento farmacológico , Imagem de Difusão por Ressonância Magnética/métodos , Feminino , Humanos , Pessoa de Meia-Idade , Imagem Multimodal , Distribuição Normal , Reconhecimento Automatizado de Padrão , Estudos Prospectivos , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes
5.
Aust N Z J Obstet Gynaecol ; 59(3): 375-379, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30088669

RESUMO

OBJECTIVE: To examine the association between inter-twin delivery interval and short-term perinatal outcomes of the second twin after vaginal delivery of the first twin. METHODS: Retrospective cohort study including twin pregnancies with a vaginal delivery of the first twin between January 2011 and September 2017 in a tertiary hospital in Melbourne, Australia. The main outcome measure was a composite of adverse neonatal outcome (at least one of perinatal death, admission to neonatal intensive care unit (NICU), endotracheal intubation, Apgar <7 at five minutes and cord lactate >4.0 mmol/L). Proportions of adverse outcomes for the second twin were compared between groups of intervals ≤ or >10 and ≤ or >30 min. RESULTS: The composite adverse neonatal outcome occurred in 201 (58.2%) and a caesarean section occurred in seven cases (2%) of the 345 pregnancies included. Delivery interval was associated with higher cord lactate. Low Apgar scores were more frequent with intervals >30 min (17.9% vs 6.6%, P = 0.03), as well as caesarean section for the second twin (10.7% vs 1.3%, P = 0.01). Composite adverse outcome and admission to NICU were not significantly influenced by the delivery interval. Predictors of adverse outcome were gestational age, abnormal cardiotocography and breech delivery of the second twin. CONCLUSION: The inter-twin delivery interval is associated with higher rates of low Apgar scores and higher cord lactate for the second twin. These associations do not translate into higher rates of admission to NICU and their long-term clinical implications are uncertain.


Assuntos
Parto Obstétrico/métodos , Gravidez de Gêmeos , Adulto , Índice de Apgar , Cesárea , Estudos de Coortes , Feminino , Humanos , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Vitória
6.
Nephrol Dial Transplant ; 33(suppl_2): ii41-ii50, 2018 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-30137583

RESUMO

This systematic review, initiated by the European Cooperation in Science and Technology Action Magnetic Resonance Imaging Biomarkers for Chronic Kidney Disease (PARENCHIMA), focuses on potential clinical applications of magnetic resonance imaging in renal non-tumour disease using magnetic resonance relaxometry (MRR), specifically, the measurement of the independent quantitative magnetic resonance relaxation times T1 and T2 at 1.5 and 3Tesla (T), respectively. Healthy subjects show a distinguishable cortico-medullary differentiation (CMD) in T1 and a slight CMD in T2. Increased cortical T1 values, that is, reduced T1 CMD, were reported in acute allograft rejection (AAR) and diminished T1 CMD in chronic allograft rejection. However, ambiguous findings were reported and AAR could not be sufficiently differentiated from acute tubular necrosis and cyclosporine nephrotoxicity. Despite this, one recent quantitative study showed in renal transplants a direct correlation between fibrosis and T1 CMD. Additionally, various renal diseases, including renal transplants, showed a moderate to strong correlation between T1 CMD and renal function. Recent T2 studies observed increased values in renal transplants compared with healthy subjects and in early-stage autosomal dominant polycystic kidney disease (ADPKD), which could improve diagnosis and progression assessment compared with total kidney volume alone in early-stage ADPKD. Renal MRR is suggested to be sensitive to renal perfusion, ischaemia/oxygenation, oedema, fibrosis, hydration and comorbidities, which reduce specificity. Due to the lack of standardization in patient preparation, acquisition protocols and adequate patient selection, no widely accepted reference values are currently available. Therefore this review encourages efforts to optimize and standardize (multi-parametric) protocols to increase specificity and to tap the full potential of renal MRR in future research.


Assuntos
Biomarcadores/análise , Nefropatias/patologia , Rim/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Guias de Prática Clínica como Assunto/normas , Progressão da Doença , Humanos
7.
Fetal Diagn Ther ; 41(3): 197-201, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27561094

RESUMO

INTRODUCTION: Monochorionic-diamniotic (MCDA) twin pregnancies are high risk, due to twin-to-twin transfusion syndrome (TTTS), twin anaemia polycythaemia sequence (TAPS) and intrauterine growth restriction (IUGR). There is limited evidence to guide ultrasound surveillance protocols. Using a retrospective cohort, we aimed to provide insight into the optimal interval of ultrasound surveillance. METHODS: Retrospective cohort of women with MCDA pregnancies who received antenatal care at Monash Medical Centre (January 2011-October 2014). We reviewed all ultrasounds from ≥15 weeks' gestation and collected perinatal outcomes. RESULTS: A total of 162 women with MCDA pregnancies attended our care. Six women were excluded due to late referral. Of the remaining 156, 55% were uncomplicated. TTTS, TAPS, IUGR and fetal demise in utero occurred in 9%, 1%, 31% and 2%, respectively. Median interval between the last ultrasound and TTTS diagnosis was 3.1 weeks (IQR 0.8-5.8). There was a trend towards a longer interval for cases with advanced TTTS compared to early TTTS. Interval between ultrasound scans was longer in cases with unexplained fetal demise in utero and advanced TTTS than early TTTS [3.4 weeks (IQR 2.0-6.9) vs. 0.9 weeks (IQR 0.4-3.7); p < 0.05]. DISCUSSION: Our observations support current recommendations for fortnightly ultrasound surveillance in MCDA pregnancies from 16 weeks' gestation and suggest that longer intervals may be associated with poorer outcomes.


Assuntos
Retardo do Crescimento Fetal/diagnóstico por imagem , Transfusão Feto-Fetal/diagnóstico por imagem , Gêmeos Monozigóticos , Ultrassonografia Pré-Natal/normas , Adulto , Estudos de Coortes , Feminino , Morte Fetal/prevenção & controle , Retardo do Crescimento Fetal/mortalidade , Transfusão Feto-Fetal/mortalidade , Idade Gestacional , Humanos , Gravidez , Estudos Retrospectivos , Fatores de Tempo , Ultrassonografia Pré-Natal/efeitos adversos
8.
Postgrad Med J ; 92(1090): 447-9, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26903663

RESUMO

AIM: Adequate sick-day management at home can reduce the risk of progression to diabetic ketoacidosis and admission to hospital. The aim of this project was to review the management of diabetes during illness. METHOD: The Association of Children's Diabetes Clinicians (ACDC) carried out a questionnaire survey of all paediatric diabetes units. In addition, parents of children with type 1 diabetes completed an online questionnaire. RESULTS: The survey of 127 units had a 73% response rate. Sick-day management guidelines were in place in 93%. All guidelines advised giving extra insulin during illness. In 67%, the extra dose was based on a fraction of total daily dose. 22% used units per kg body weight (U/kg). 21% used locally derived formulae to calculate extra dose of insulin. 3% of units advised only blood ketone monitoring. Although all units had an out-of-hours access policy for the families, 45% received advice from the general paediatric registrar. Only in 15%, the advice was directly from a member of the paediatric diabetes team. 680 parents completed the questionnaire. 86% reported receiving training on managing sick days. The majority (52.2%) receiving an informal session at diagnosis. 40% did not know what to do in the presence of raised blood glucose and high blood ketones. CONCLUSIONS: There was a wide variation in the practice of monitoring and advice given during illness. Both surveys highlight need for national guidance as well and to improve quality of sick-day rule education programmes for parents of children with type 1 diabetes.


Assuntos
Automonitorização da Glicemia/métodos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Serviço Hospitalar de Emergência/estatística & dados numéricos , Fidelidade a Diretrizes , Hospitalização/estatística & dados numéricos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Pais/educação , Glicemia , Criança , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 1/epidemiologia , Cetoacidose Diabética , Guias como Assunto , Inquéritos Epidemiológicos , Humanos , Pais/psicologia , Inquéritos e Questionários , Reino Unido/epidemiologia
9.
Am J Obstet Gynecol MFM ; 6(4): 101345, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38479490

RESUMO

BACKGROUND: Poor outcomes from operative vaginal birth have been associated with failure to recognize malposition, breakdown in interdisciplinary communication, and deviation from accepted guidelines. We recently implemented a safety bundle including routine intrapartum ultrasound and a structured time-out and procedural checklist aiming to reduce maternal and perinatal morbidity from operative vaginal birth. OBJECTIVE: This study aimed to compare births where intrapartum ultrasound was used and those where it was not used during a safety bundle implementation period at Monash Health. STUDY DESIGN: We performed a retrospective cohort study at Monash Health during the transitional phase of implementing an operative vaginal birth safety bundle. We studied all women with operative vaginal birth and fully dilated cesarean delivery with a singleton cephalic term fetus. We compared births for which intrapartum ultrasound was used and those for which it was not. The primary outcome was neonates delivered in an unexpected position. Neonatal and maternal morbidity were also assessed, including a neonatal composite of Apgar score <7 at 5 minutes, cord lactate >8 mmol/L, need for resuscitation, significant birth trauma, or neonatal intensive care unit admission. To control for confounding by indication, we estimated propensity scores for the probability of using intrapartum ultrasound for each case based on maternal and labor characteristics, and adjusted the effect estimates for the propensity scores using multivariable logistic regression models. RESULTS: From August 2022 to July 2023, there were 1205 operative vaginal births or fully dilated cesarean deliveries at Monash Health, including 743 (61.7%) forceps, 346 (28.7%) vacuum, and 116 (9.6%) fully dilated cesarean deliveries. Over this time, we observed increased uptake of intrapartum ultrasound from 26% in August 2022 to 60% (P<.001) in July 2023, of the time-out from 21% to 58% (P<.001), and the checklist from 33% to 80% (P<.001) of operative second-stage births. Among the births where intrapartum ultrasound was used (n=509), compared with those where it was not (n=696), there were significantly more forceps births (67% vs 58%; adjusted odds ratio, 1.35; 95% confidence interval, 1.05-1.74; P=.021) and a reduction in vacuum births (24% vs 32%; adjusted odds ratio, 0.77; 95% confidence interval, 0.58-1.01; P=.059). There were no significant differences in fully dilated cesarean delivery or maternal morbidity. Intrapartum ultrasound use was associated with significantly fewer infants being delivered in an unexpected position (0.2% vs 2.2%; adjusted odds ratio, 0.08; 95% confidence interval, 0.00-0.44; P=.019) and a significant reduction in composite neonatal morbidity (22% vs 25%; adjusted odds ratio, 0.73; 95% confidence interval, 0.54-0.97; P=.031). CONCLUSION: During the implementation of a safety bundle, the use of ultrasound before operative vaginal birth was associated with fewer infants delivered in an unexpected position and reduced neonatal morbidity.


Assuntos
Cesárea , Humanos , Feminino , Estudos Retrospectivos , Gravidez , Adulto , Recém-Nascido , Cesárea/estatística & dados numéricos , Cesárea/métodos , Ultrassonografia Pré-Natal/métodos , Ultrassonografia Pré-Natal/estatística & dados numéricos , Índice de Apgar , Extração Obstétrica/métodos , Extração Obstétrica/estatística & dados numéricos , Estudos de Coortes , Pontuação de Propensão , Lista de Checagem/métodos , Vácuo-Extração/estatística & dados numéricos , Vácuo-Extração/métodos , Vácuo-Extração/efeitos adversos
10.
Methods Mol Biol ; 2216: 187-204, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33476001

RESUMO

The specialized function of the kidney is reflected in its unique structure, characterized by juxtaposition of disorganized and ordered elements, including renal glomerula, capillaries, and tubules. The key role of the kidney in blood filtration, and changes in filtration rate and blood flow associated with pathological conditions, make it possible to investigate kidney function using the motion of water molecules in renal tissue. Diffusion-weighted imaging (DWI) is a versatile modality that sensitizes observable signal to water motion, and can inform on the complexity of the tissue microstructure. Several DWI acquisition strategies are available, as are different analysis strategies, and models that attempt to capture not only simple diffusion effects, but also perfusion, compartmentalization, and anisotropy. This chapter introduces the basic concepts of DWI alongside common acquisition schemes and models, and gives an overview of specific DWI applications for animal models of renal disease.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This introduction chapter is complemented by two separate chapters describing the experimental procedure and data analysis.


Assuntos
Biomarcadores/análise , Imagem de Difusão por Ressonância Magnética/métodos , Imagem de Tensor de Difusão/métodos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Rim/fisiologia , Monitorização Fisiológica/métodos , Animais , Humanos , Software
11.
Methods Mol Biol ; 2216: 611-635, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33476027

RESUMO

Analysis of renal diffusion-weighted imaging (DWI) data to derive markers of tissue properties requires careful consideration of the type, extent, and limitations of the acquired data. Alongside data quality and general suitability for quantitative analysis, choice of diffusion model, fitting algorithm, and processing steps can have consequences for the precision, accuracy, and reliability of derived diffusion parameters. Here we introduce and discuss important steps for diffusion-weighted image processing, and in particular give example analysis protocols and pseudo-code for analysis using the apparent diffusion coefficient (ADC) and intravoxel incoherent motion (IVIM) models. Following an overview of general principles, we provide details of optional steps, and steps for validation of results. Illustrative examples are provided, together with extensive notes discussing wider context of individual steps, and notes on potential pitfalls.This publication is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This analysis protocol chapter is complemented by two separate chapters describing the basic concepts and experimental procedure.


Assuntos
Algoritmos , Imagem de Difusão por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Processamento de Imagem Assistida por Computador/métodos , Rim/fisiologia , Monitorização Fisiológica/métodos , Animais , Software
12.
Methods Mol Biol ; 2216: 419-428, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33476014

RESUMO

Renal diffusion-weighted imaging (DWI) can be used to obtain information on the microstructure of kidney tissue, and has the potential to provide MR-biomarkers for functional renal imaging. Here we describe in a step-by-step experimental protocol the MRI method for measuring renal diffusion coefficients in rodents using ADC or IVIM models. Both methods provide quantification of renal diffusion coefficients; however, IVIM, a more complex model, allows for the calculation of the pseudodiffusion and fraction introduced by tissue vascular and tubular components. DWI provides information of renal microstructure contributing to the understanding of the physiology and the underlying processes that precede the beginning of pathologies.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers. This experimental protocol chapter is complemented by two separate chapters describing the basic concept and data analysis.


Assuntos
Biomarcadores/análise , Imagem de Difusão por Ressonância Magnética/métodos , Processamento de Imagem Assistida por Computador/métodos , Rim/fisiologia , Animais , Meios de Contraste , Camundongos , Monitorização Fisiológica , Software
13.
Methods Mol Biol ; 2216: 3-23, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33475991

RESUMO

Renal MRI holds incredible promise for making a quantum leap in improving diagnosis and care of patients with a multitude of diseases, by moving beyond the limitations and restrictions of current routine clinical practice. Clinical and preclinical renal MRI is advancing with ever increasing rapidity, and yet, aside from a few examples of renal MRI in routine use, it is still not good enough. Several roadblocks are still delaying the pace of progress, particularly inefficient education of renal MR researchers, and lack of harmonization of approaches that limits the sharing of results among multiple research groups.Here we aim to address these limitations for preclinical renal MRI (predominantly in small animals), by providing a comprehensive collection of more than 40 publications that will serve as a foundational resource for preclinical renal MRI studies. This includes chapters describing the fundamental principles underlying a variety of renal MRI methods, step-by-step protocols for executing renal MRI studies, and detailed guides for data analysis. This collection will serve as a crucial part of a roadmap toward conducting renal MRI studies in a robust and reproducible way, that will promote the standardization and sharing of data.This chapter is based upon work from the COST Action PARENCHIMA, a community-driven network funded by the European Cooperation in Science and Technology (COST) program of the European Union, which aims to improve the reproducibility and standardization of renal MRI biomarkers.


Assuntos
Biomarcadores/análise , Nefropatias/classificação , Nefropatias/patologia , Rim/fisiopatologia , Imageamento por Ressonância Magnética/métodos , Guias de Prática Clínica como Assunto/normas , Progressão da Doença , Humanos , Nefropatias/terapia , Reprodutibilidade dos Testes
14.
Eur J Appl Physiol ; 109(3): 417-28, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20140447

RESUMO

The purpose of the study was to determine the effects of two nights of sleep deprivation with or without energy restriction on immune indices at rest and in response to cold exposure. On three randomised occasions ten males slept normally [mean (SD): 436 (21) min night(-1); CON], were totally sleep-deprived (SDEP), or were totally sleep-deprived and 90% energy-restricted (SDEP + ER) for 53 h. After 53 h (1200 h) participants performed a seated cold air test (CAT) at 0.0 degrees C until T (re) decreased to 36.0 degrees C. Circulating leucocyte counts, neutrophil degranulation, stress hormones and saliva secretory IgA (S-IgA) were determined at 0 h, 24 h, 48 h, pre-CAT, post-CAT, 1-h and 2-h post-CAT. One night on SDEP increased bacterially stimulated neutrophil degranulation (21%, P < 0.05), and two nights on SDEP and SDEP + ER increased S-IgA concentration (40 and 44%; P < 0.01). No other significant effects were observed for immuno-endocrine measures prior to CAT. CAT duration was not different between trials [mean (SD): 133 (53) min] and T (re) decreased to 35.9 (0.3) degrees C. Modest whole-body cooling decreased circulating lymphocyte counts (25%; P < 0.01), S-IgA concentration (36%; P < 0.01) and secretion rate (24%; P < 0.05). A neutrophilia occurred post-CAT on CON and SDEP and 2-h post-CAT on SDEP + ER (P < 0.01). Modest whole-body cooling also decreased neutrophil degranulation on CON (22%) and SDEP (18%; P < 0.05). Plasma cortisol and norepinephrine increased post-CAT (31 and 346%, P < 0.05), but modest whole-body cooling did not alter plasma epinephrine. In conclusion, two nights of SDEP or SDEP + ER did not compromise resting immune indices. However, modest whole-body cooling (T(re) 35.9 degrees C) decreased circulating lymphocytes, neutrophil degranulation and S-IgA, but responses were not amplified by prior SDEP or SDEP + ER.


Assuntos
Restrição Calórica , Hipotermia Induzida , Monitorização Imunológica , Privação do Sono/imunologia , Estresse Fisiológico/imunologia , Adulto , Glicemia/metabolismo , Peso Corporal , Degranulação Celular , Epinefrina/sangue , Humanos , Hidrocortisona/sangue , Imunoglobulina A Secretora/metabolismo , Contagem de Leucócitos , Masculino , Monitorização Imunológica/métodos , Atividade Motora , Neutrófilos/imunologia , Norepinefrina/sangue , Volume Plasmático , Saliva/imunologia , Privação do Sono/sangue , Privação do Sono/fisiopatologia , Fatores de Tempo , Adulto Jovem
15.
Aust N Z J Obstet Gynaecol ; 50(6): 534-8, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21133864

RESUMO

AIMS: Prelabour rupture of membranes (PROM), whether at term or preterm, can be a difficult diagnosis to confirm. Clinician uncertainty often leads to unnecessary intervention for risk management reasons. Amnisure® is a bedside immunoassay for placental alpha macroglobulin-1 (PAMG-1), which has been shown to have high sensitivity and specificity in the diagnosis of PROM. However, whether the use of Amnisure® alters clinical management remains untested. The objective of this study was to assess the clinical utility of Amnisure®. METHODS: A prospective cohort study of 184 women presenting with a history of PROM to a tertiary maternity hospital. Before and after Amnisure® , the attending clinician assessed and recorded membrane status (PROM or intact), his/her level of confidence in this diagnosis, and the intended management plan. RESULTS: There was clinician uncertainty regarding the diagnosis of PROM in 83 (47%) women. Amnisure® significantly increased clinician confidence and led to a change of intended management in 23 (13%) women. In 33 women presenting with possible preterm PROM, seven thought to have PROM before Amnisure® had a negative test, leading to a change of management in these women. CONCLUSIONS: Amnisure® is clinically useful when the clinician is uncertain about the diagnosis but not useful when the clinician is confident about the diagnosis. The use of Amnisure® in women where the diagnosis is uncertain is likely to significantly change management, including reduced hospitalisation for women with preterm PROM.


Assuntos
Ruptura Prematura de Membranas Fetais/diagnóstico , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/análise , Feminino , Ruptura Prematura de Membranas Fetais/terapia , Humanos , Imunoensaio , Gravidez
16.
Sci Rep ; 10(1): 3141, 2020 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-32081989

RESUMO

External cephalic version (ECV) is associated with a moderate degree of pain. Virtual reality (VR) is a technology that has shown promise in offering procedural analgesia. We undertook a clinical pilot to assess the viability of VR to reduce pain during ECV. In an open randomised controlled trial (RCT), we randomised 50 women to either VR or standard care each (25 per group). Women receiving VR were administered VR content (Skylights) via a headset. Pre- and post-procedural measures of pain, anxiety, device experience and vital signs were measured. There were no significant differences between groups (VR/no VR) in pain scores (60.68 vs 49.76; p = 0.2), ECV success rates (80% vs 76%; p = 0.7) or anxiety levels. The women receiving VR had a significantly higher anticipation of pain pre-procedurally (70.0 vs 50.0; p = 0.03). 20 (80%) of the VR women indicated that they would use VR again and 22 (88%) indicated they would recommend it to a friend having ECV. There were no significant differences between groups for side effects encountered or changes in vital signs. We have shown that using VR during ECV is feasible and appears safe. Our results inform the design of future RCTs.


Assuntos
Analgesia/métodos , Manejo da Dor/métodos , Versão Fetal/métodos , Realidade Virtual , Adulto , Ansiedade , Simulação por Computador , Estudos de Viabilidade , Feminino , Humanos , Dor , Medição da Dor/métodos , Projetos Piloto , Gravidez , Versão Fetal/efeitos adversos
17.
Am J Case Rep ; 19: 386-391, 2018 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-29606699

RESUMO

BACKGROUND This report presents therapeutic decision-making and management of refractory, life-threatening duodenal bleeding in a young man with recurrent metastatic retroperitoneal paraganglioma. CASE REPORT The patient had been symptom free for 8 years after radioactive MIBG (metaiodobenzylguanidine) therapy. Failure of endoscopic or angiographic bleeding control led to urgent need to evaluate possible endocrine functional status, tumor curability, safety of incomplete resection, intra- and postoperative support needs, and anticipated recovery potential and postoperative function. Aside from these considerations, impact of tumor biology, alternative therapeutic options, current management guidelines, and ethical challenges of resource utilization for such complex palliative operative intervention were reviewed. CONCLUSIONS Based on the observed outcomes after an urgent presentation of an unusual tumor-related complication, palliation-intent therapy was justifiable even if significant treatment-related risks were expected and complex resources were required.


Assuntos
Tomada de Decisões , Duodenopatias/terapia , Hemorragia Gastrointestinal/terapia , Cuidados Paliativos/métodos , Paraganglioma/complicações , Neoplasias Retroperitoneais/complicações , Adulto , Duodenopatias/diagnóstico , Duodenopatias/etiologia , Hemorragia Gastrointestinal/diagnóstico , Hemorragia Gastrointestinal/etiologia , Humanos , Masculino , Recidiva Local de Neoplasia , Paraganglioma/diagnóstico , Neoplasias Retroperitoneais/diagnóstico , Tomografia Computadorizada por Raios X
18.
BMJ Open ; 8(2): e017451, 2018 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-29455162

RESUMO

OBJECTIVES: The aim of this study was to evaluate the implementation of the Practical Obstetric Multi-Professional Training (PROMPT) simulation using the Kirkpatrick's framework. We explored participants' acquisition of knowledge and skills, its impact on clinical outcomes and organisational change to integrate the PROMPT programme as a credentialing tool. We also aimed to assess participants' perception of usefulness of PROMPT in their clinical practice. STUDY DESIGN: Mixed methods approach with a pre-test/post-test design. SETTING: Healthcare network providing obstetric care in Victoria, Australia. PARTICIPANTS: Medical and midwifery staff attending PROMPT between 2013 and 2015 (n=508); clinical outcomes were evaluated in two cohorts: 2011-2012 (n=15 361 births) and 2014-2015 (n=12 388 births). INTERVENTION: Attendance of the PROMPT programme, a simulation programme taught in multidisciplinary teams to facilitate teaching emergency obstetric skills. MAIN OUTCOME MEASURE: Clinical outcomes compared before and after embedding PROMPT in educational practice. SECONDARY OUTCOME MEASURE: Assessment of knowledge gained by participants through a qualitative analysis and description of process of embedding PROMPT in educational practice. RESULTS: There was a change in the management of postpartum haemorrhage by early recognition and intervention. The key learning themes described by participants were being prepared with a prior understanding of procedures and equipment, communication, leadership and learning in a safe, supportive environment. Participants reported a positive learning experience and increase in confidence in managing emergency obstetric situations through the PROMPT programme, which was perceived as a realistic demonstration of the emergencies. CONCLUSION: Participants reported an improvement of both clinical and non-technical skills highlighting principles of teamwork, communication, leadership and prioritisation in an emergency situation. An improvement was observed in management of postpartum haemorrhage, but no significant change was noted in clinical outcomes over a 2-year period after PROMPT. However, the skills acquired by medical and midwifery staff justify embedding PROMPT in educational programmes.


Assuntos
Educação/normas , Conhecimentos, Atitudes e Prática em Saúde , Pessoal de Saúde/educação , Tocologia/educação , Obstetrícia/educação , Hemorragia Pós-Parto/terapia , Competência Clínica , Feminino , Humanos , Equipe de Assistência ao Paciente , Gravidez , Resultado da Gravidez , Aprendizagem Baseada em Problemas/métodos , Vitória
19.
EBioMedicine ; 33: 276-281, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29941341

RESUMO

BACKGROUND: Ectopic pregnancies are a leading cause of maternal mortality. Most are treated surgically. We evaluated the efficacy and safety of combining oral gefitinib (epidermal growth factor receptor inhibitor) with methotrexate to treat larger ectopic pregnancies. METHODS: We performed a phase II, single arm, open label study across four hospitals in Edinburgh and Melbourne. We recruited women with a stable tubal ectopic pregnancy and a pre-treatment serum hCG between 1000 and 10,000 IU/L. We administered intramuscular methotrexate (50 mg/m2) once, and oral gefitinib (250 mg) for seven days. The primary outcome was the percentage successfully treated without needing surgery. To show the treatment is at least 70% effective, 28 participants were required, and 24 or more successfully treated without surgery. Secondary outcomes were safety, tolerability, and time to resolution. This study is registered (ACTRN12611001056987). FINDINGS: 30 participants with stable tubal ectopic pregnancies were recruited but two withdrew, leaving 28 participants. The median (± range) pre-treatment serum hCG was 2039 (1031-8575) IU/L and nine had pre-treatment hCGs levels >3000 IU/L. The treatment successfully resolved 86% (24/28) cases with a median (±range) time to resolution of 32 (18-67) days. The treatment caused transient rash and diarrhoea, but no serious adverse events. INTERPRETATION: Combination gefitinib and methotrexate is at least 70% effective in resolving ectopic pregnancies with a pre-treatment serum hCG 1000-10,000 IU/L. This may be a new way to treat most stable ectopic pregnancies, but needs to be validated via a randomised clinical trial.


Assuntos
Gonadotropina Coriônica/sangue , Metotrexato/administração & dosagem , Gravidez Ectópica/tratamento farmacológico , Quinazolinas/administração & dosagem , Administração Intranasal , Administração Oral , Adulto , Quimioterapia Combinada , Feminino , Gefitinibe , Humanos , Metotrexato/efeitos adversos , Gravidez , Gravidez Ectópica/sangue , Quinazolinas/efeitos adversos , Resultado do Tratamento
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