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1.
Biochem Med (Zagreb) ; 33(2): 020705, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37324115

RESUMEN

Introduction: Although current guidelines recommend not drinking coffee prior to phlebotomy, our hypothesis is that drinking coffee does not affect the clinical interpretation of biochemical and haematological test results. Materials and methods: Twenty-seven volunteers were studied in basal state (T0) and 1h after (T1) drinking coffee. Routine haematological (Sysmex-XN1000 analyser) and biochemistry parameters (Vitros 4600 analyser) were studied. Results were compared using the Wilcoxon test (P < 0.05). A clinical change was considered when mean percent difference (MD%) was higher than the reference change value (RCV). Results: Coffee intake produced statistically, but not clinically, significant: i) increases in haemoglobin (P = 0.009), mean cell haemoglobin concentration (P = 0.044), neutrophils (P = 0.001), albumin (P = 0.001), total protein (P = 0.000), cholesterol (P = 0.025), high density lipoprotein cholesterol (P = 0.007), uric acid (P = 0.011), calcium (P = 0.001), potassium (P = 0.010), aspartate aminotransferase (P = 0.001), amylase (P = 0.026), and lactate dehydrogenase (P = 0.001), and ii) decreases in mean cell volume (P = 0.002), red cell distribution width (P = 0.001), eosinophils (P = 0.002), and lymphocytes (P = 0.001), creatinine (P = 0.001), total bilirubin (P = 0.012), phosphorus (P = 0.001), magnesium (P = 0.007), and chloride (P = 0.001). Conclusion: Drinking a cup of coffee 1 hour prior to phlebotomy produces no clinically significant changes in routine biochemical and haematological test results.


Asunto(s)
Pruebas Hematológicas , Flebotomía , Humanos , Flebotomía/métodos , Pruebas de Coagulación Sanguínea , Colesterol , Hemoglobinas
2.
Bioanalysis ; 15(12): 673-681, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37272603

RESUMEN

Aim: To describe the stability of nafamostat in infusion solutions, during blood sample collection and in extracted plasma samples in the autosampler. Methods: Nafamostat infusion solutions were stored at room temperature in the light for 24 h. For sample collection stability, fresh blood spiked with nafamostat was subjected to combinations of anticoagulants, added esterase inhibitor and temperature. Nafamostat was monitored in the extracted plasma samples in the autosampler. Results: Nafamostat was stable in infusion solutions. Nafamostat in whole blood was stable for 3 h before centrifugation when collected in sodium fluoride/potassium oxalate tubes (4°C). Nafamostat in extracted plasma samples degraded at 4.7 ± 0.7% per h. Conclusion: Viable samples can be obtained using blood collection tubes with sodium fluoride, chilling and processing promptly.


Asunto(s)
Anticoagulantes , Fluoruro de Sodio , Humanos , Infusiones Intravenosas , Anticoagulantes/farmacología , Temperatura , Resultado del Tratamiento
3.
Biochem Med (Zagreb) ; 33(1): 010901, 2023 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-36817854

RESUMEN

Introduction: Blood samples having inappropriate volume are a substantial part of preanalytical errors. Inadequate sample volume for glycated haemoglobin (HbA1c) test may be a common problem of patients with diabetes mellitus having vascular changes. In this study, we compared HbA1c concentrations of underfilled and appropriately filled blood collection tubes. Materials and methods: To compare HbA1c concentrations, blood samples were collected into 2 mL tubes containing K3-EDTA from 109 subjects. Two blood samples (underfilled and appropriately filled) were drawn from a patient by the same personnel and materials. HbA1c measurements were assayed on a Cobas 6000 analyser module c 501 (Roche Diagnostics, Mannheim, Germany). The HbA1c% results were compared by t-test and Wilcoxon's signed-rank statistical methods (SPSS Inc., Chicago, USA). Bias analysis was performed using Microsoft Excel 4.0. Results: Underfilled samples were classified three groups (group 1, N = 44; group 2, N = 36; and group 3, N = 29) according to the filling ratio of the samples; 0.5 mL and below (< 25%), 0.5-1.0 mL (25-50%), and 1.0-2.0 mL (> 50%), respectively. When we compared underfilled tubes with pairing filled tubes, there was a statistically significant difference only with tubes filled less than 25% (P = 0.030). Furthermore, we have done bias analysis between paired tubes according to the diagnostic cut-off value of 6.5%. The bias was more prominent in up to 50% underfilled blood tubes (1.1%), when HbA1c concentrations were below the diagnostic cut-off of 6.5%. Conclusions: We suggest that the blood tubes with EDTA for HbA1c measurement should be filled with at least 50% to avoid clinical variations.


Asunto(s)
Recolección de Muestras de Sangre , Diabetes Mellitus , Humanos , Ácido Edético , Hemoglobina Glucada , Recolección de Muestras de Sangre/métodos , Diabetes Mellitus/diagnóstico , Bioensayo
4.
Enferm Intensiva (Engl Ed) ; 34(1): 19-26, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36774248

RESUMEN

INTRODUCTION: Drawing blood samples through a central venous catheter (CVC) is a customary practice in Intensive Care Units (ICUs). It is indicated to discard a volume of waste blood to avoid interference in the results. AIM: To determine whether a lower discard volume for obtaining blood samples from temporary CVCs placed into the internal jugular, femoral or subclavian vein offers valid results. METHOD: A quasi-experimental prospective cross-sectional study for which sixty-five patients of over 18 years of age in ICUs, who had been fitted with a triple lumen central venous catheter, were recruited over a period of eight months. Two consecutive blood samples were extracted with tubes for biochemistry, coagulation and hemogram from each patient from the distal lumen. The first sample was obtained with a discarded waste of 1.5 ml from a total extracted volume of 10.2 ml, similar to the usual waste in our ambit (10 ml). Subsequently the second sample was obtained. The paired t-test was used to analyse the data. The Bland-Altman plot and intraclass correlation coefficient (ICC) were used to measure the agreement between methods. The reference change value (RCV) was established as the admissible limit of variation between the pairs of samples. RESULTS: A total of 65 sample pairs were drawn (intervention-control). The paired t-test found statistically significant differences with a significance level of α = .05 for chlorine (-.536; .012); prothrombin time (-.092; .019) and prothrombin activity (.284; 1.375).The ICC was greater than .9 in all the variables and the limit determined for the RCV was not surpassed by any value. CONCLUSIONS: The results show the reliability of the blood samples drawn with a discard volume of 1.5 ml.


Asunto(s)
Catéteres Venosos Centrales , Enfermedad Crítica , Humanos , Adolescente , Adulto , Estudios Prospectivos , Reproducibilidad de los Resultados , Estudios Transversales
5.
Enferm. intensiva (Ed. impr.) ; 34(1): 19-26, Ene-Mar. 2023. tab
Artículo en Español | IBECS | ID: ibc-214981

RESUMEN

Introducción: La extracción de muestras sanguíneas a través de un catéter venoso central es una práctica habitual en las unidades de cuidados intensivos. Está indicado desechar un volumen de sangre, denominado volumen de descarte, con la finalidad de evitar que los resultados puedan verse alterados. Objetivo: Determinar si un menor volumen de descarte para la obtención de analíticas procedentes de catéter venoso central temporales alojados en la vena yugular interna, femoral o subclavia ofrece resultados válidos. Método: Estudio cuasiexperimental, prospectivo, transversal donde se seleccionaron 65 pacientes críticos mayores de 18 años portadores de catéter venoso central temporal de 3 luces durante un período de 8 meses. Para cada paciente se extrajeron 2 analíticas consecutivas de la luz distal con los valores de hemograma, bioquímica y coagulación comúnmente analizados en el paciente crítico. Se obtuvieron 2 muestras consecutivas: la primera, con un descarte de 1,5ml y un volumen extraído total de 10,2ml, similar al desecho habitual en nuestro medio (10 ml). Seguidamente se obtuvo la segunda muestra. Para el análisis de datos se utilizó la prueba t pareada; para medir la concordancia entre métodos, la representación de Bland-Altman y el coeficiente de correlación intraclase. Se estableció el valor de referencia del cambio como límite admisible de variación entre los pares de muestras. Resultados: Se extrajeron un total de 65 pares de muestras (intervención-control). El contraste de medias encontró diferencias estadísticamente significativas con α=0,05 para cloro (−0,536; 0,012), tiempo de protrombina (−0,092; 0,019) y actividad de protrombina (0,284; 1,375). El coeficiente de correlación intraclase resultó mayor de 0,9 en todas las variables y el valor de referencia del cambio no fue superado por ningún valor. Conclusiones: Los resultados muestran la validez de los análisis de las muestras de sangre extraídas con un volumen de descarte de 1,5ml.(AU)


Introduction: Drawing blood samples through a central venous catheter is a customary practice in intensive care units. It is indicated to discard a volume of waste blood to avoid interference in the results. Aim: To determine whether a lower discard volume for obtaining blood samples from temporary central venous catheters placed into the internal jugular, femoral or subclavian vein offers valid results. Method: A quasi-experimental prospective cross-sectional study for which 65 patients of over 18 years of age in intensive care units, who had been fitted with a triple lumen central venous catheter, were recruited over a period of 8 months. Two consecutive blood samples were extracted with tubes for biochemistry, coagulation and haemogram from each patient from the distal lumen. The first sample was obtained with a discarded waste of 1.5ml from a total extracted volume of 10.2ml, similar to the usual waste in our ambit (10ml). Subsequently the second sample was obtained. The paired t-test was used to analyse the data. The Bland-Altman plot and intraclass correlation coefficient were used to measure the agreement between methods. The reference change value was established as the admissible limit of variation between the pairs of samples. Results: A total of 65 sample pairs were drawn (intervention-control). The paired t-test found statistically significant differences with a significance level of α=0.05 for chlorine (−0.536; 0.012); prothrombin time (−0.092; 0.019) and prothrombin activity (0.284; 1.375). The intraclass correlation coefficient was greater than 0.9 in all the variables and the limit determined for the reference change value was not surpassed by any value. Conclusions: The results show the reliability of the blood samples drawn with a discard volume of 1.5ml.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Recolección de Muestras de Sangre , Catéteres Venosos Centrales , Análisis Químico de la Sangre , Unidades de Cuidados Intensivos , Anemia , Enfermería , Enfermería de Cuidados Críticos , Estudios Prospectivos , Estudios Transversales
6.
Rev. cuba. enferm ; 38(1)mar. 2022.
Artículo en Español | LILACS, BDENF - Enfermería, CUMED | ID: biblio-1408321

RESUMEN

Introducción: El hemocultivo es una prueba sencilla, pero existe el riesgo de contaminación por un inadecuado procedimiento, en muchas ocasiones puede estar relacionado con la mala praxis del personal de enfermería. Objetivo: Valorar el nivel de conocimientos sobre la técnica de extracción de hemocultivo en enfermeras de una Unidad de Cuidados Intensivos. Métodos: Se realizó estudio descriptivo, transversal, en la Unidad de Cuidados Intensivos del Centro Nacional de Cirugía de Mínimo Acceso, La Habana, en enero 2021. La población estuvo conformada por 12 licenciadas en enfermería, se aplicó un cuestionario de conocimiento con la escala de puntuación: 0-30 puntos (no conocimiento); 31-60 puntos (poco conocimiento); 61-90 puntos (adecuado conocimiento), 91-100 puntos (excelente conocimiento). Se calcularon las frecuencias absolutas, porcentaje, prueba T para una muestra y chi cuadrado. Se utilizó el programa IBM SPSS versión 20 para Windows. Resultados: De la muestra estudiada, 41,70 por ciento consideró que el hemocultivo se realiza a pacientes febriles y el uso de guantes estériles como único medio de protección; 33,30 por ciento hizo referencia al alcohol como antiséptico cutáneo de elección; 58,30 % planteó que se inoculan con diez ml de sangre y 66,70 por ciento afirmó que se debe comenzar por el aeróbico. El promedio de puntuación general fue de 64,25. Conclusiones: Los profesionales de enfermería mostraron un adecuado conocimiento, los guantes estériles fueron el medio de protección más utilizado, destaca el uso de alcohol 76 por ciento para la desinfección de la piel, diez mililitros es el volumen de sangre considerado a inocular en los frascos, existe adherencia a los protocolos de transporte y conservación de la muestra(AU)


Introduction: Blood culture is a simple test, but there is a risk of contamination due to an inadequate procedure, which many times can be related to malpractice of the nursing personnel. Objective: To assess the level of knowledge about the blood culture extraction technique in nurses of an intensive care unit. Methods: A descriptive and cross-sectional study was carried out in the intensive care unit of the National Center for Minimal Access Surgery, Havana, in January 2021. The population consisted of twelve registered nurses. A knowledge questionnaire was applied, which included the following scoring scale: 0-30 points (no knowledge), 31-60 points (little knowledge), 61-90 points (adequate knowledge), 91-100 points (excellent knowledge). Absolute frequencies, percentage, T-test for one sample and chi-square were calculated. The program IBM SPSS (version 20) for Windows was used. Results: Of the sample studied, 41.70 percent considered that blood culture is performed on febrile patients and the use of sterile gloves as the only means of protection. 33.30 percent referred alcohol as the skin antiseptic of choice. 58.30 percent stated that test tube or flask inoculation is completed with 10 mL of blood. 66.70 percent stated that the technique should start with the aerobic. The average overall score was 64.25. Conclusions: Nursing professionals showed adequate knowledge. Sterile gloves were the most used means of protection. The use of 76 percent-alcohol for skin disinfection is relevant. The volume of blood to empty into the flask or sample tube is 10 mL. The protocols for sample preservation and transport are followed(AU)


Asunto(s)
Humanos , Recolección de Muestras de Sangre/métodos , Unidades de Cuidados Intensivos , Mala Praxis , Personal de Enfermería , Estudios Transversales , Contaminación Ambiental , Factores Protectores
7.
J Pharm Sci ; 110(10): 3491-3499, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34126115

RESUMEN

It is common practice to use cannulated rats for pharmacokinetic (PK) in-life studies as it yields high quality PK parameter estimation. While offering many benefits, cannulation requires surgery, post-surgical care, and cannula maintenance. As an alternative approach, the strategy of dosing and bleeding rats via the tail vein in a single experiment is technically feasible and theoretically offers many benefits. Unfortunately, however, as reported by F Tse et al. in 1984 (J Pharm Sci 73: https://doi.org/10.1002/jps.2600731128), parallel tail dosing and bleeding is scientifically flawed and yields inaccurate estimation of PK parameters following intravenous administration. The underlying causality of poor data quality has not been addressed in over 35 years. To overcome the technical flaws associated with parallel tail dosing and bleeding, we have developed a Tail-Dose-Bleed (TDB) method as a substitute for use of cannulated rats. Specifically, the method introduces a flush procedure after dosing, uses separate tail veins for dosing and bleeding, and adjusts dosing and sampling to the proximal and distal portions of the tail, respectively. To demonstrate the proof of principle for this TDB technique, several cassette dosing studies were conducted. The performance of the TDB technique is compared in both stand alone and animal crossover studies employing conventional jugular/femoral bleeding and dosing. The poor data via tail dosing and bleeding previously described by Tse et al. are also recapitulated using their described approach. To ensure broad applicability of the TDB technique, data were generated utilizing compounds of diverse physical chemical properties manifesting a range of clearance and/or volume of distribution characteristics. These data demonstrate that the TDB approach yields comparable PK profiles and parameters as compared to conventional femoral dosing / jugular bleeding. Using this newly described TDB procedure, we demonstrate the ability to overcome documented data quality issues when dosing and bleeding via the tail. The TDB technique has numerous operational advantages of reduced study turnaround time and improved cost effectiveness, but most importantly, addresses key animal welfare concerns relevant to institutional animal care and use committees (IACUC). The notable advantage here is reduced animal stress and discomfort by eliminating the need for surgery and recovery. And by consequence, allows for animals to be group housed and re-used without concern for loss of cannula patency. The tail dose and bleed method is simple and appears readily transferable to other laboratories.


Asunto(s)
Recolección de Muestras de Sangre , Cola (estructura animal) , Administración Intravenosa , Animales , Exactitud de los Datos , Cinética , Ratas
8.
J Perianesth Nurs ; 36(4): 328-333, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33771443

RESUMEN

Central line-associated bloodstream infections occur not only in the intensive care unit but also the non-intensive care units of the hospital. The purpose of this article is to review current evidence to guide perianesthesia nurses in the care of a patient with a central vascular access device (CVAD). The CVAD bundle focuses on five key elements: hand hygiene, maximal sterile barrier, chlorhexidine antiseptic, catheter site selection, and daily evaluation of the need for the device. Once the CVAD is placed, evidence-based care and maintenance are the responsibility of the nurse. Ensuring proper maintenance and care of a CVAD falls within nursing practice and interventions can significantly reduce the patient's risk of central line-associated bloodstream infection. The single most crucial step a nurse can take to help prevent central line-associated bloodstream infections is performing proper hand hygiene. Other interventions focus on dressing management, bathing practices, access of intravenous infusion sets, blood draws, and management of port line occlusions. Familiarity and adoption of best practice interventions in the maintenance and care of patients with CVADs will help the perianesthesia nurse protect patients and prevent harm.


Asunto(s)
Infecciones Relacionadas con Catéteres , Cateterismo Venoso Central , Vendajes , Infecciones Relacionadas con Catéteres/prevención & control , Cateterismo Venoso Central/efectos adversos , Enfermería Basada en la Evidencia , Humanos , Unidades de Cuidados Intensivos
9.
Acta bioquím. clín. latinoam ; 53(4): 469-476, dic. 2019. graf, tab
Artículo en Español | LILACS | ID: biblio-1124024

RESUMEN

El propósito de este estudio fue analizar los cambios post prandiales en el perfil lipídico en respuesta a una comida típica argentina. Se extrajo sangre a 33 mujeres voluntarias después de 12 h de ayuno (T0), 1 h después de un desayuno estandarizado (T1) y 1 h después de un almuerzo estandarizado (T2). Se midieron los niveles de: colesterol total, colesterol de lipoproteínas de alta densidad (C-HDL), colesterol de lipoproteínas de baja densidad (C-LDL) y triglicéridos. Los datos se analizaron utilizando la prueba t de Student pareada. Para cada analito se calculó la diferencia porcentual media (DM%) en T1 y T2 respecto de T0 y se comparó con el valor de referencia del cambio (VRC). Las DM% mayores al VRC se consideraron clínicamente significativas. En T1 y T2, los valores de C-HDL fueron más bajos que en T0, mientras que los valores de C-LDL en T1 fueron más bajos que en T0. Los niveles de triglicéridos fueron significativamente más altos en T1 que en T0. En todos los casos, la variabilidad fue estadísticamente significativa, aunque no clínicamente. En este estudio puede observarse que el perfil de lípidos en T1 y T2 no mostró diferencias clínicamente significativas con respecto a los valores basales.


The purpose of the present study was to analyze postprandial lipid profile changes in response to a typical Argentine meal. Blood was collected from 33 female volunteers after a 12 h fasting period (T0), 1 h after a standardized breakfast (T1) and 1 h after a standardized lunch (T2). The levels of total cholesterol, high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), and triglycerides were measured. Data were analyzed using paired Student's t-test. Mean difference % (MD %) was calculated for each analyte at T1 and T2 and was further compared with reference change value (RCV). MDs % higher than RCV were considered clinically significant. At T1 and T2, HDL-C values were lower than at T0, whereas LDL-C values at T1 were lower than at T0. Triglycerides levels were significantly higher at T1 than baseline values. In all cases, variability was statistically, though not clinically, significant. This study demonstrates that at T1 and T2 lipid profile showed no clinically significant differences with respect to basal values.


O objetivo do presente estudo foi analisar as alterações do perfil lipídico pós-prandial em resposta a uma refeição típica argentina. O sangue foi coletado de 33 mulheres voluntárias após um período de jejum de 12 horas (T0),1 h após um café da manhã padronizado (T1) e 1 h após um almoço padronizado (T2). Foram medidos os níveis de: colesterol total (CT), colesterol HDL (C-HDL), colesterol LDL (C-LDL) e triglicérides. Os dados foram analisados utilizando o teste t de Student pareado. A diferença média% (DM%) foi calculada para cada analito em T1 e T2 e foi comparada com o valor de mudança de referência (VRC). Os MDs% maiores que o VRC foram considerados clinicamente significativos. Em T1 e T2, os valores de C-HDL foram menores que em T0, enquanto os valores de C-LDL em T1 foram menores que em T0. Os níveis de triglicérides foram significativamente maiores em T1 do que os valores basais. Em todos os casos, a variabilidade foi estatisticamente, embora não clinicamente, significativa. Este estudo demonstra que no perfil lipídico em T1 e T2 não houve diferenças clinicamente significativas em relação aos valores basais.


Asunto(s)
Humanos , Triglicéridos , Sangre , Colesterol , Ayuno , Ayuno/sangre , Comidas , Desayuno , Fase Preanalítica/estadística & datos numéricos , Lípidos , Lípidos/análisis , Lipoproteínas , HDL-Colesterol , LDL-Colesterol , Polvos , Derivación y Consulta , Café , Almuerzo , Lipoproteínas LDL
10.
Biochem Med (Zagreb) ; 28(1): 010702, 2018 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-29187795

RESUMEN

INTRODUCTION: Currently available recommendations regarding fasting requirements before phlebotomy do not specify any maximum water intake volume permitted during the fasting period. The aim was to study the effects of 300 mL water intake 1 h before phlebotomy on specific analytes. MATERIALS AND METHODS: Blood was collected from 20 women (median age (min-max): 24 (22 - 50) years) in basal state (T0) and 1 h after 300 mL water intake (T1). Glucose, total proteins (TP), urea, creatinine, cystatin C, total bilirubin (BT), total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, triglycerides (Tg), uric acid (UA), high-sensitivity C-reactive protein, gamma-glutamyl transferase (GGT), aspartate-aminotransferase (AST), alanine-aminotransferase and lactate-dehydrogenase (LD) were studied. Results were analyzed using Wilcoxon test. Mean difference (%) was calculated for each analyte and was further compared with reference change value (RCV). Only mean differences (%) higher than RCV were considered clinically significant. RESULTS: Significant differences (median T0vs median T1, P) were observed for TP (73 vs 74 g/L, 0.001); urea (4.08 vs 4.16 mmol/L, 0.010); BT (12 vs 13 µmol/L, 0.021); total cholesterol (4.9 vs 4.9 mmol/L, 0.042); Tg (1.05 vs 1.06 mmol/L, 0.002); UA (260 vs 270 µmol/L, 0.006); GGT (12 vs 12 U/L, 0.046); AST (22 vs 24 U/L, 0.001); and LD (364 vs 386 U/L, 0.001). Although the differences observed were statistically significant, they were not indicative of clinically significant changes. CONCLUSIONS: A water intake of 300 mL 1 h prior to phlebotomy does not interfere with the analytes studied in the present work.


Asunto(s)
Química Clínica/métodos , Agua/química , Adulto , Colesterol/sangre , Ingestión de Líquidos , Ayuno , Femenino , Humanos , L-Lactato Deshidrogenasa/sangre , Persona de Mediana Edad , Triglicéridos/sangre , Adulto Joven , gamma-Glutamiltransferasa/sangre
11.
Curr Protoc Mouse Biol ; 3(2): 101-19, 2013 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-26069060

RESUMEN

Basic phenotyping of inbred mouse strains and genetically modified mouse models usually includes the determination of blood-based parameters as a diagnostic screen for genotype effects on metabolism and organ function. A broad range of analytes, including hematological parameters, can be reliably determined in mouse blood, if appropriate samples are available. Here we describe recommended techniques for blood collection from mice and the considerations that have to be taken into account to get adequate samples for hematological investigations. Furthermore, we describe established methods used in the German Mouse Clinic (GMC) to determine hematological parameters in the mouse. Curr. Protoc. Mouse Biol. 3:101-119 © 2013 by John Wiley & Sons, Inc.

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