Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 155
Filtrar
1.
Gait Posture ; 108: 361-366, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38227996

RESUMO

BACKGROUND: Clubfoot patients show good-to-excellent foot correction after the Ponseti method. Nevertheless, underlying functional problems that limit motor abilities such as one-leg-standing and one-leg-hopping still persist. These restrictions have been proposed to arise due to problems with maintaining balance and the limited force-generating capacity of clubfoot patients. More insight is needed to understand the underlying limiting factors to improve overall motor ability in clubfoot patients. RESEARCH QUESTION: The aim of this study was to determine the differences between clubfoot patients and typically developing children (TDC) in force and balance parameters during walking, one-leg-standing and hopping. METHODS: Three-dimensional motion analysis was performed in 19 TDC and 16 idiopathic Ponseti-treated clubfoot patients between 5-9 years old. Kinematic and kinetic parameters were calculated during walking and one-leg-hopping. To describe the balance parameters, center of pressure (CoP) data was assessed during walking, one-leg-hopping and one-leg-standing. Mean group values were calculated and compared using nonparametric statistical tests. A general linear model with repeated measures was used to determine which activity showed the largest group differences. RESULTS: Clubfoot patients showed lower peak plantarflexor moment and peak ankle power absorption and generation during one-leg-hopping compared to TDC. Furthermore, clubfoot patients showed a lower hop length and velocity than TDC. The difference in peak plantarflexor moment and ankle power between the study groups was larger during one-leg-hopping than during walking. Finally, clubfoot patients showed a higher anterior-posterior CoP range during one-leg-standing. SIGNIFICANCE: Deviations in force parameters seemed to limit one-leg-hopping in clubfoot patients, and impaired anterior-posterior static balance was thought to be the underlying cause of problems with one-leg-standing. Furthermore, one-leg-hopping was more sensitive to distinguish between clubfoot patients and TDC than walking. Individualized physiotherapy targeting static balance and force parameters, with extra emphasis on including eccentric contractions, might improve the overall motor abilities of clubfoot patients.


Assuntos
Tornozelo , Pé Torto Equinovaro , Criança , Humanos , Pré-Escolar , Perna (Membro) , Movimento ,
2.
Gait Posture ; 93: 47-53, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35066401

RESUMO

BACKGROUND: Altered muscle-tendon properties in clubfoot patients could play a role in the occurrence of a relapse and negatively affect physical functioning. However, there is a lack of literature about muscle-tendon properties of clubfoot relapse patients. RESEARCH QUESTION: The aim of this study was to determine whether the muscle architecture of the medial gastrocnemius and the morphology of the Achilles tendon differ between typically developing children (TDC) and clubfoot patients with and without a relapse clubfoot and to determine the relationships between morphological and functional gait outcomes. METHODS: A cross-sectional study was carried out in clubfoot patients treated according to the Ponseti method and TDC aged 4-8 years. A division between clubfoot patients with and without a relapse was made. Fifteen clubfoot patients, 10 clubfoot relapse patients and 19 TDC were included in the study. Morphologic properties of the medial head of the Gastrocnemius muscle and Achilles tendon were assessed by ultrasonography. Functional gait outcomes were assessed using three-dimensional gait analysis. Mean group differences were analysed with ANOVA and non-parametric alternatives. Relationships between functional and morphologic parameters were determined for all clubfoot patients together and for TDC with Spearman's rank correlation. RESULTS: Morphological and functional gait parameters did not differ between clubfoot patients with and without a relapse, with exception of lower maximal dorsiflexor moment in clubfoot relapse patients. Compared to TDC, clubfoot and relapse patients did show lower functional gait outcomes, as well as shorter and more pennate muscles with a longer Achilles tendon. In all clubfoot patients, this longer relative tendon was related to higher ankle power and plantarflexor moment. SIGNIFICANCE: In clubfoot and relapse patients, abnormalities in morphology did not always relate to worse functional gait outcomes. Understanding these relationships in all clubfoot patients may improve the knowledge about clubfoot and aid future treatment planning.


Assuntos
Tendão do Calcâneo , Pé Torto Equinovaro , Criança , Estudos Transversais , Marcha/fisiologia , Humanos , Músculo Esquelético , Recidiva , Resultado do Tratamento
3.
Gait Posture ; 90: 415-421, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34583148

RESUMO

BACKGROUND: Understanding the kinematic characteristics of relapse clubfoot compared to successfully treated clubfoot could aid early identification of a relapse and improve treatment planning. The usage of a multi segment foot model is essential in order to grasp the full complexity of the multi-planar and multi-joint deformity of the clubfoot. RESEARCH QUESTION: The purpose of this study was to identify differences in foot kinematics, using a multi-segment foot model, during gait between patients with Ponseti treated clubfoot with and without a relapse and age-matched healthy controls. METHODS: A cross-sectional study was carried out including 11 patients with relapse clubfoot, 11 patients with clubfoot and 15 controls. Gait analysis was performed using an extended Helen Hayes model combined with the Oxford Foot Model. Statistical analysis included statistical parametric mapping and discrete analysis of kinematic gait parameters of the pelvis, hip, knee, ankle, hindfoot and forefoot in the sagittal, frontal and transversal plane. RESULTS: The relapse group showed significantly increased forefoot adduction in relation with the hindfoot and the tibia. Furthermore, this group showed increased forefoot supination in relation with the tibia during stance, whereas during swing increased forefoot supination in relation with the hindfoot was found in patients with relapse clubfoot compared with non-relapse clubfoot. SIGNIFICANCE: Forefoot adduction and forefoot supination could be kinematic indicators of relapse clubfoot, which might be useful in early identification of a relapse clubfoot. Subsequently, this could aid the optimization of clinical decision making and treatment planning for children with clubfoot.


Assuntos
Pé Torto Equinovaro , Fenômenos Biomecânicos , Criança , Pé Torto Equinovaro/terapia , Estudos Transversais , Marcha , Humanos , Recidiva , Supinação
4.
Sci Rep ; 10(1): 9647, 2020 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32541874

RESUMO

Background The effect of bracing over natural history of stable dysplastic hips is not well known. This multicenter randomized trial aimed at objectifying the effect of abduction treatment versus active surveillance in infants of 3 to 4 months of age. Methods Patients were randomized to either Pavlik harness or active surveillance group. Ultrasound was repeated at 6 and 12 weeks post randomization. The primary outcome was the degree of dysplasia using the Graf α-angle at 6 months of age. The measurement of the acetabular index (AI) on plain pelvis X-rays was used to identify persistent dysplasia after 9 months and walking age (after 18 months). Findings The Pavlik harness group (n = 55) and active surveillance group (n = 49) were comparable for predictors of outcome. At 12 weeks follow-up the mean α-angle was 60.5° ± 3.8° in the Pavlik harness group and 60.0° ± 5.6° in the active surveillance group. (p = 0.30). Analysis of secondary outcomes (standard of care) showed no treatment differences for acetabular index at age 10 months (p = 0.82) and walking age (p = 0.35). Interpretation Pavlik harness treatment of stable but sonographic dysplastic hips has no effect on acetabular development. Eighty percent of the patients will have a normal development of the hip after twelve weeks. Therefore, we recommend observation rather than treatment for stable dysplastic hips.


Assuntos
Acetábulo/diagnóstico por imagem , Acetábulo/crescimento & desenvolvimento , Luxação do Quadril/terapia , Feminino , Luxação do Quadril/diagnóstico por imagem , Humanos , Lactente , Masculino , Aparelhos Ortopédicos , Resultado do Tratamento , Conduta Expectante
5.
Case Rep Orthop ; 2020: 7834969, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32351749

RESUMO

Posttraumatic cyst-like lesions are a rare finding after greenstick fractures in children. These asymptomatic, cystic lesions become radiologically apparent 2-4 months after the initial trauma. Conventional radiographs typically show nonexpansile, well-circumscribed lesions in the cortex, proximal to the fracture site. It is important to recognize them as benign to prevent unnecessary concern and additional imaging or invasive diagnostic procedures. No treatment is indicated, as they eventually resolve spontaneously in 1 to 3 years. The two cases of posttraumatic cyst-like lesions after paediatric forearm fractures are presented.

6.
Clin Biomech (Bristol, Avon) ; 60: 185-190, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30388514

RESUMO

BACKGROUND: In clinical practice, clubfeet feel stiffer compared to healthy feet. Furthermore, the clinical impression is that stiffer clubfeet have a higher tendency to relapse. Until now, no objective measure has been available to determine the stiffness of clubfeet. The goal of the current project was to objectively quantify ankle and subtalar joint stiffness in clubfeet patients and to compare this stiffness between clubfeet patients and healthy controls using a newly developed measurement device. METHODS: The newly developed Torque-Displacement-Handpiece in combination with an adjusted Abduction Dorsiflexion Mechanism clubfoot-brace, made it possible to move a foot over two rotational axis, while continuously capturing the applied torque and the achieved angulation. Based on this information, stiffness of the ankle and subtalar joint were assessed for 11 clubfoot patients with 17 clubfeet and 11 healthy subjects with 22 healthy feet. FINDINGS: With the Torque-Displacement-Handpiece measuring device it was possible to measure torque, angulation and stiffness in a reliable and precise manner. Clubfoot patients showed less angulation and a higher stiffness for measurements over the ADM subtalar axis compared to controls. After adjusting for shoe size, the stiffness for measurements over the ADM tibiotalar axis was also significantly higher in clubfeet than controls. INTERPRETATION: Overall, these results indicate that clubfoot patients have a higher ankle and subtalar joint stiffness in the affected joint compared to healthy controls. In the future, the Torque-Displacement-Handpiece could be used to monitor stiffness of clubfeet during treatment, and as such, play a potential role in the early detection of relapsing clubfeet.


Assuntos
Pé Torto Equinovaro/fisiopatologia , Artropatias/fisiopatologia , Articulação Talocalcânea/fisiopatologia , Tornozelo , Articulação do Tornozelo/fisiopatologia , Braquetes , Criança , Pré-Escolar , Feminino , Pé/fisiopatologia , Humanos , Masculino , Ortopedia , Recidiva , Torque , Resultado do Tratamento
7.
Gait Posture ; 66: 94-100, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30170140

RESUMO

BACKGROUND: Currently, the Ponseti method is the gold standard for treatment of clubfeet. For long-term functional evaluation of this method, gait analysis can be performed. Previous studies have assessed gait differences between Ponseti treated clubfeet and healthy controls. RESEARCH QUESTION/PURPOSE: The aims of this systematic review were to compare the gait kinetics of Ponseti treated clubfeet with healthy controls and to compare the gait kinetics between clubfoot patients treated with the Ponseti method or surgically. METHODS: A systematic search was performed in Embase, Medline Ovid, Web of Science, Scopus, Cochrane, Cinahl ebsco, and Google scholar, for studies reporting on gait kinetics in children with clubfeet treated with the Ponseti method. Studies were excluded if they only used EMG or pedobarography. Data were extracted and a risk of bias was assessed. Meta-analyses and qualitative analyses were performed. RESULTS: Nine studies were included, of which five were included in the meta-analyses. The meta-analyses showed that ankle plantarflexor moment (95% CI -0.25 to -0.19) and ankle power (95% CI -0.89 to -0.60, were significantly lower in the Ponseti treated clubfeet compared to the healthy controls. No significant difference was found in ankle dorsiflexor and plantarflexor moment, and ankle power between clubfeet treated with surgery compared to the Ponseti method. SIGNIFICANCE: Differences in gait kinetics are present when comparing Ponseti treated clubfeet with healthy controls. However, there is no significant difference between surgically and Ponseti treated clubfeet. These results give more insight in the possibilities of improving the gait pattern of patients treated for clubfeet.


Assuntos
Moldes Cirúrgicos , Pé Torto Equinovaro/terapia , Marcha/fisiologia , Criança , Pé Torto Equinovaro/fisiopatologia , Feminino , Humanos , Masculino , Manipulação Ortopédica , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento
8.
PLoS One ; 13(6): e0199540, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29933405

RESUMO

BACKGROUND: Clubfeet are commonly treated using the Ponseti method. This method involves weekly manipulation and casting which gradually corrects the position of the foot. However, the reasons for following a weekly interval are not clear. QUESTION / PURPOSE: The aim is to investigate the influence of the cast change interval on treatment outcomes in the Ponseti method. METHODS: We performed a systematic review of comparative studies in which the cast change interval was varied. Scientific databases were searched for relevant publications, screened for eligibility and assessed for a risk of bias. A 'best evidence' synthesis tool was used to synthesize the results of the included studies and draw conclusions from relevant clinical outcomes. RESULTS: Nine papers matched the inclusion criteria, which provided data of 587 subjects who had a total of 870 clubfeet. There is strong evidence for a positive relation between cast change interval and treatment duration. However, there is no evidence for any relation between the cast change interval and the required number of casts, tenotomy rate, required surgery or failure rate. CONCLUSIONS: Accelerated versions are as effective and safe as the traditional Ponseti method. However, more research is needed to assess the long-term results and to identify an optimal cast change interval.


Assuntos
Moldes Cirúrgicos , Pé Torto Equinovaro/terapia , Humanos , Fatores de Tempo
9.
J Thromb Haemost ; 16(1): 142-149, 2018 01.
Artigo em Inglês | MEDLINE | ID: mdl-29065247

RESUMO

Essentials Two candidate International Standards for thromboplastin (coded RBT/16 and rTF/16) are proposed. International Sensitivity Index (ISI) of proposed standards was assessed in a 20-centre study. The mean ISI for RBT/16 was 1.21 with a between-centre coefficient of variation of 4.6%. The mean ISI for rTF/16 was 1.11 with a between-centre coefficient of variation of 5.7%. SUMMARY: Background The availability of International Standards for thromboplastin is essential for the calibration of routine reagents and hence the calculation of the International Normalized Ratio (INR). Stocks of the current Fourth International Standards are running low. Candidate replacement materials have been prepared. This article describes the calibration of the proposed Fifth International Standards for thromboplastin, rabbit, plain (coded RBT/16) and for thromboplastin, recombinant, human, plain (coded rTF/16). Methods An international collaborative study was carried out for the assignment of International Sensitivity Indexes (ISIs) to the candidate materials, according to the World Health Organization (WHO) guidelines for thromboplastins and plasma used to control oral anticoagulant therapy with vitamin K antagonists. Results Results were obtained from 20 laboratories. In several cases, deviations from the ISI calibration model were observed, but the average INR deviation attributabled to the model was not greater than 10%. Only valid ISI assessments were used to calculate the mean ISI for each candidate. The mean ISI for RBT/16 was 1.21 (between-laboratory coefficient of variation [CV]: 4.6%), and the mean ISI for rTF/16 was 1.11 (between-laboratory CV: 5.7%). Conclusions The between-laboratory variation of the ISI for candidate material RBT/16 was similar to that of the Fourth International Standard (RBT/05), and the between-laboratory variation of the ISI for candidate material rTF/16 was slightly higher than that of the Fourth International Standard (rTF/09). The candidate materials have been accepted by WHO as the Fifth International Standards for thromboplastin, rabbit plain, and thromboplastin, recombinant, human, plain.


Assuntos
Anticoagulantes/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Monitoramento de Medicamentos/normas , Coeficiente Internacional Normatizado/normas , Tempo de Protrombina/normas , Tromboplastina/normas , Animais , Calibragem , Humanos , Ensaio de Proficiência Laboratorial , Variações Dependentes do Observador , Valor Preditivo dos Testes , Coelhos , Proteínas Recombinantes/normas , Padrões de Referência , Reprodutibilidade dos Testes
10.
J Thromb Haemost ; 15(3): 500-506, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-28055147

RESUMO

Essentials Differences in sensitivity to factor VII (FVII) have been suggested between thromboplastins. FVII-induced International Normalized Ratio (INR) changes differ between commercial reagents. Recombinant human thromboplastins are more sensitive to FVII than tissue-extract thromboplastins. Thromboplastin choice may affect FVII-mediated INR stability. SUMMARY: Background Differences regarding sensitivity to factor VII have been suggested for recombinant human and tissue-extract thromboplastins used for International Normalized Ratio (INR) measurement, but the evidence is scarce. Differences in FVII sensitivity are clinically relevant, as they can affect INR stability during treatment with vitamin K antagonists (VKAs). Objectives To determine whether commercial thromboplastins react differently to changes in FVII. Methods We studied the effect of addition of FVII on the INR in plasma by using three tissue-extract (Neoplastin C1+, Hepato Quick, and Thromborel S) and three recombinant human (Recombiplastin 2G, Innovin, and CoaguChek XS) thromboplastins. Three different concentrations of purified human FVII (0.006, 0.012 and 0.062 µg mL-1 plasma), or buffer, were added to five certified pooled plasmas of patients using VKAs (INR of 1.5-3.5). Changes in FVII activity were measured with two bioassays (Neoplastin and Recombiplastin), and relative INR changes were compared between reagents. Results After addition of 0.062 µg mL-1 FVII, FVII activity in the pooled plasmas increased by approximately 20% (Neoplastin) or 32% (Recombiplastin) relative to the activity in pooled normal plasma. All thromboplastins showed dose-dependent INR decreases. The relative INR change in the pooled plasmas significantly differed between the six thromboplastins. No differences were observed among recombinant or tissue-extract thromboplastins. Pooled results indicated that the FVII-induced INR change was greater for recombinant than for tissue-extract thromboplastins. Conclusions Differences regarding FVII sensitivity exist between various thromboplastins used for VKA monitoring. Recombinant human thromboplastins are more sensitive to FVII than tissue-extract thromboplastins. Therefore, thromboplastin choice may affect FVII-mediated INR stability.


Assuntos
Fator VII/química , Tromboplastina/química , Vitamina K/antagonistas & inibidores , Anticoagulantes/química , Bioensaio , Testes de Coagulação Sanguínea , Fibrinolíticos/química , Hemostáticos/química , Humanos , Coeficiente Internacional Normatizado , Plasma/efeitos dos fármacos , Tempo de Protrombina , Proteínas Recombinantes/química
12.
Thromb Haemost ; 116(4): 679-86, 2016 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-27384264

RESUMO

Patients receiving vitamin K-antagonists are monitored by regular assessment of the International Normalized Ratio (INR). There are two popular methods for therapeutic control of anticoagulation in patient groups: 1) Time in Therapeutic Range (TTR) assessed by linear interpolation of successive INR measurements; 2) the cross-sectional proportion (CSP) of all patients' last INRs within range. The purpose of the present study is to compare the two methods using data from 53 Dutch Thrombosis Centres and to develop a semi-quantitative model for TTR based on different types of INR change. Different groups of around 400,000 patients in four consecutive years were evaluated: patients in the induction phase, short-term, long-term, low-target range, high-target range, receiving either acenocoumarol or phenprocoumon, and performing self-management. Each Centre provided TTR and CSP results for each patient group. TTR and CSP were compared using the Wilcoxon signed-rank test. Separately, we analysed the relationship between consecutive INR results regarding in or out of range and their frequency of occurrence in patients of two different cohorts. Good correlation was observed between TTR and CSP (correlation coefficient 0.694-0.950 in low-target range). In long-term acenocoumarol patients (low-target range) the median TTR was significantly higher than CSP (80.0 % and 78.7 %, respectively; p<0.001). In long-term phenprocoumon patients (low-target range) there was no significant difference between median TTR (83.0 %) and median CSP (82.6 %). In conclusion, the correlation between TTR assessed by linear interpolation and CSP was good. TTR assessed by linear interpolation was higher than CSP in patients on acenocoumarol.


Assuntos
Anticoagulantes/administração & dosagem , Coeficiente Internacional Normatizado , Vitamina K/antagonistas & inibidores , Humanos , Modelos Teóricos , Países Baixos
13.
Thromb Res ; 139: 128-34, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26916310

RESUMO

Major orthopaedic surgery is associated with an increased risk of venous thromboembolism. Direct oral anticoagulants (DOACs) are recommended as thromboprophylactic agents after orthopaedic surgery. Although routine monitoring of DOACs in general is not required, measuring DOAC concentration may be necessary in clinical settings. The effects of DOACs on routine coagulation assays in spiked material are studied extensively, however, few data are available on DOAC concentration in patients after major orthopaedic surgery. We measured trough and peak DOAC concentrations with UPLC-MS/MS and routine coagulation tests in a prospective study including 40 patients receiving thromboprophylactic treatment with dabigatran 220mg od and 40 patients receiving rivaroxaban 10mg od after major orthopaedic surgery. For rivaroxaban, the median trough concentration with UPLC-MS/MS was 17.1ng/mL and median peak concentration was 149ng/mL. The anti-Xa assay displayed a good correlation, but a positive bias in comparison to the reference method. Furthermore, trough levels were mostly below the LOD of the anti-Xa assay. For dabigatran, the median trough concentration with UPLC-MS/MS was 12.1ng/mL, and median peak level was 80.8ng/mL. A positive bias was found when results from coagulation assays were compared to UPLC-MS/MS data. However, the addition of glucuronidated metabolites to dabigatran concentration UPLC-MS/MS data generally resolved most of this bias. Age was found to have a significant influence on dabigatran pharmacokinetics, irrespective of kidney function, whereas no effect of age was found during rivaroxaban treatment. In both treatment groups, female subjects displayed faster pharmacokinetics in comparison to male subjects, although not reaching significance. We conclude that UPLC-MS/MS is the method of choice to measure trough concentrations of DOACs in patients after orthopaedic surgery. Current coagulation assays are not suited for this purpose. We found large heterogeneity in both peak and trough concentrations of DOACs, and showed that pharmacokinetics of novel oral anticoagulants may be influenced by age and gender. Whether patients with high or low trough concentrations are at increased risk for bleeding or thromboembolic events respectively remains to be established.


Assuntos
Anticoagulantes/sangue , Dabigatrana/sangue , Procedimentos Ortopédicos , Rivaroxabana/sangue , Tromboembolia Venosa/prevenção & controle , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Coagulação Sanguínea/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão/métodos , Dabigatrana/uso terapêutico , Monitoramento de Medicamentos/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Ortopédicos/efeitos adversos , Rivaroxabana/uso terapêutico , Espectrometria de Massas em Tandem/métodos , Tromboembolia Venosa/etiologia
14.
J Thromb Haemost ; 14(4): 695-703, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26806724

RESUMO

BACKGROUND: Point-of-care (POC) international normalized ratio (INR) monitoring by healthcare professionals could eliminate the need for venous blood sampling in non-self-monitoring (NSM) patients on vitamin K antagonists (VKA). However, few studies have investigated the impact of POC INR monitoring on the quality of treatment in these patients and real-world data on this issue are lacking. OBJECTIVES: To investigate the safety, efficacy and quality of anticoagulant control during POC INR monitoring as compared with laboratory INR monitoring in NSM patients. METHODS: We performed a retrospective cohort study using data from the anticoagulation clinic of the Star-Medical Diagnostic Center (Rotterdam, the Netherlands). Patients who received treatment with VKA between 29 May 2012 and 29 May 2014 were eligible. Percentage of time in therapeutic range (TTR) and incidence rates of major clinical events (all-cause mortality, hospitalization, major bleeding and ischemic stroke) were compared for the year before and year after introduction of POC monitoring. Cox proportional hazard models were used to estimate hazard ratios and 95% confidence intervals for major clinical events between exposure groups. RESULTS: In total, 1973 patients during the 1-year laboratory-monitoring observation period and 1959 patients during the 1-year POC-monitoring observation period were included. Median TTR was significantly lower during POC monitoring (77.9%; 95% CI, 67.2-87.4) than during laboratory INR monitoring (81.0%; 95% CI, 71.1-90.5). Adjusted hazard ratios for major clinical events were all around unity. CONCLUSIONS: Although associated with lower TTR, POC INR monitoring is a safe and effective alternative to laboratory INR monitoring in NSM patients on VKA.


Assuntos
Monitorização Fisiológica/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Vitamina K/antagonistas & inibidores , Idoso , Anticoagulantes/química , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/mortalidade , Feminino , Seguimentos , Próteses Valvulares Cardíacas , Humanos , Coeficiente Internacional Normatizado , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Qualidade da Assistência à Saúde , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do Tratamento , Tromboembolia Venosa/tratamento farmacológico , Tromboembolia Venosa/mortalidade
15.
Thromb Haemost ; 114(6): 1260-7, 2015 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-26202616

RESUMO

Many patients treated with vitamin K antagonists (VKA) determine their INR using point-of-care (POC) whole blood coagulation monitors. The primary aim of the present study was to assess the INR within-subject variation in self-testing patients receiving a constant dose of VKA. The second aim of the study was to derive INR imprecision goals for whole blood coagulation monitors. Analytical performance goals for INR measurement can be derived from the average biological within-subject variation. Fifty-six Thrombosis Centres in the Netherlands were invited to select self-testing patients who were receiving a constant dose of either acenocoumarol or phenprocoumon for at least six consecutive INR measurements. In each patient, the coefficient of variation (CV) of INRs was calculated. One Thrombosis Centre selected regular patients being monitored with a POC device by professional staff. Sixteen Dutch Thrombosis Centres provided results for 322 selected patients, all using the CoaguChek XS. The median within-subject CV in patients receiving acenocoumarol (10.2 %) was significantly higher than the median CV in patients receiving phenprocoumon (8.6 %) (p = 0.001). The median CV in low-target intensity acenocoumarol self-testing patients (10.4 %) was similar to the median CV in regular patients monitored by professional staff (10.2 %). Desirable INR analytical imprecision goals for POC monitoring with CoaguChek XS in patients receiving either low-target intensity acenocoumarol or phenprocoumon were 5.1 % and 4.3 %, respectively. The approximate average value for the imprecision of the CoaguChek XS, i. e. 4 %, is in agreement with these goals.


Assuntos
Acenocumarol/uso terapêutico , Anticoagulantes/uso terapêutico , Coeficiente Internacional Normatizado , Testes Imediatos , Vitamina K/antagonistas & inibidores , Varfarina/uso terapêutico , Acenocumarol/administração & dosagem , Acenocumarol/farmacologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/administração & dosagem , Confiabilidade dos Dados , Feminino , Humanos , Coeficiente Internacional Normatizado/instrumentação , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Autocuidado , Varfarina/administração & dosagem , Varfarina/farmacologia , Adulto Jovem
16.
Thromb Res ; 136(1): 164-7, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25959582

RESUMO

BACKGROUND: Long-term stability is an essential requirement for all international biological standards. The main stocks of the current international standards for thromboplastin, i.e. RBT/05 (rabbit brain thromboplastin) and rTF/09 (recombinant human tissue factor), are stored at -20°C. The aim of the present study is to assess the long-term stability of the international sensitivity index (ISI) for RBT/05 and rTF/09. METHODS: Part of the main stocks of RBT/05 and rTF/09 were stored at -70°C and -150°C, up to 38months. At various time points samples were taken from the materials stored at -20°C, -70°C, and -150°C. The samples were reconstituted and analysed in the prothrombin time (PT) test using plasma samples derived from healthy subjects and patients treated with vitamin K-antagonists (VKA). The PT's obtained with the standards stored at -20°C were compared to the PT's obtained with the standards stored at -70°C and at -150°C. The PT's were used to calculate relative ISI values by means of orthogonal regression. RESULTS: There were no important differences between the ISI values for the materials stored at -20°C, -70°C, and -150°C. There was no significant trend with storage time. CONCLUSION: The ISI values for the international standards RBT/05 and rTF/09 appear to be stable at storage temperatures of -20°C, -70°C, and -150°C.


Assuntos
Criopreservação , Tempo de Protrombina/normas , Tromboplastina/química , Animais , Congelamento , Humanos , Coeficiente Internacional Normatizado/normas , Estabilidade Proteica , Coelhos , Proteínas Recombinantes/química , Tromboplastina/normas
17.
Thromb Res ; 135(3): 526-31, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25596767

RESUMO

BACKGROUND: Portable point-of-care (POC) instruments for determination of the whole blood prothrombin time (PT) have been available for the last three decades. Recently, two novel POC instruments for PT and International Normalized Ratio (INR) determination in whole blood have been manufactured. The purpose of this study was to compare INR values obtained with the novel instruments (microINR® and ProTime InRhythm™) to the INR determined with the international standard for thromboplastin rTF/09. MATERIALS AND METHODS: In 60 patients treated with vitamin K-antagonists, venous whole blood was analysed with four different types of POC instruments including the novel ones. In the same patients, citrated plasma was analysed with the international standard rTF/09 and the manual tilt tube technique for clotting time determination. We assessed the bias of the INR read from the POC instruments relative to the international standard. To study the imprecision of the two novel POC instruments, duplicate INR determinations were performed. RESULTS: The results obtained with the two novel POC instruments were positively correlated with those of the international standard rTF/09. However, there was a significant bias between INR read from the novel instruments and the INR determined with rTF/09 (P < 0.001). The mean bias was -13.7% (MicroINR) and -9.3% (InRhythm). The imprecision coefficient of variation in venous blood was 5.0% and 5.1%, respectively. CONCLUSION: The imprecision of the two novel instruments is acceptable with respect to the average within-subject variation of the INR. The accuracy of the systems is borderline and should be improved by the manufacturers.


Assuntos
Coeficiente Internacional Normatizado/métodos , Sistemas Automatizados de Assistência Junto ao Leito , Calibragem , Feminino , Humanos , Masculino , Tempo de Protrombina
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA