ANN-Based Discernment of Septic and Inflammatory Synovial Fluid: A Novel Method Using Viscosity Data from a QCR Sensor.

The synovial fluid (SF) analysis involves a series of chemical and physical studies that allow opportune diagnosing of septic, inflammatory, non-inflammatory, and other pathologies in joints. Among the variety of analyses to be performed on the synovial fluid, the study of viscosity can help distinguish between these conditions, since this property is affected in pathological cases. The problem with viscosity measurement is that it usually requires a large sample volume, or the necessary instrumentation is bulky and expensive. This study compares the viscosity of normal synovial fluid samples with samples with infectious and inflammatory pathologies and classifies them using an ANN (Artificial Neural Network). For this purpose, a low-cost, portable QCR-based sensor (10 MHz) was used to measure the viscous responses of the samples by obtaining three parameters: Δf, ΔΓ (parameters associated with the viscoelastic properties of the fluid), and viscosity calculation. These values were used to train the algorithm. Different versions of the ANN were compared, along with other models, such as SVM and random forest. Thirty-three samples of SF were analyzed. Our study suggests that the viscosity characterized by our sensor can help distinguish infectious synovial fluid, and that implementation of ANN improves the accuracy of synovial fluid classification.

Basal Values of Biochemical and Hematological Parameters in Elite Athletes.

The purpose of this study was to show how continuous exercise affects the basal values of biochemical and hematological parameters in elite athletes. A total of 14,010 samples (male = 8452 and female = 5558 (March 2011-March 2020)) from 3588 elite athletes (male = 2258 and female = 1330, mean age 24.9 ± 6.9 vs. 24.1 ± 5.5 years, respectively) from 32 sport modalities, were studied over 9 years to check the variation of basal biochemical and hematological parameter values. There were differences seen in the basal values of creatine kinase (CK), urea, creatinine, aspartate transaminase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH), potassium, total bilirubin, and eosinophil percentage compared to reference population data. However, other analytes showed narrow ranges of variation like glucose, total protein, albumin, sodium, hemoglobin, mean cell volume (MCV), and platelet count. Exercise produces changes in biochemical and hematological basal values of athletes compared to the general population, with the greatest variation in CK, but AST, ALT, LDH, potassium, and total bilirubin (TBil) show high values in serum, only with a wider distribution of values. The data here reflects the effect of exercise on biochemical and hematological parameter baseline ranges in elite athletes. As clinical laboratories use reference intervals to validate clinical reports, these "pseudo" reference intervals should be used when validating laboratory reports.

Characteristics and laboratory findings on admission to the emergency department among 2873 hospitalized patients with COVID-19: the impact of adjusted laboratory tests in multicenter studies. A multicenter study in Spain (BIOCOVID-Spain study).

Identification of predictors for severe disease progression is key for risk stratification in COVID-19 patients. We aimed to describe the main characteristics and identify the early predictors for severe outcomes among hospitalized patients with COVID-19 in Spain. This was an observational, retrospective cohort study (BIOCOVID-Spain study) including COVID-19 patients admitted to 32 Spanish hospitals. Demographics, comorbidities and laboratory tests were collected. Outcome was in-hospital mortality. For analysis, laboratory tests values were previously adjusted to assure the comparability of results among participants. Cox regression was performed to identify predictors. Study population included 2873 hospitalized COVID-19 patients. Nine variables were independent predictors for in-hospital mortality, including creatinine (Hazard ratio [HR]:1.327; 95% Confidence Interval [CI]: 1.040-1.695, p = .023), troponin (HR: 2.150; 95% CI: 1.155-4.001; p = .016), platelet count (HR: 0.994; 95% CI: 0.989-0.998; p = .004) and C-reactive protein (HR: 1.037; 95% CI: 1.006-1.068; p = .019). This is the first multicenter study in which an effort was carried out to adjust the results of laboratory tests measured with different methodologies to guarantee their comparability. We reported a comprehensive information about characteristics in a large cohort of hospitalized COVID-19 patients, focusing on the analytical features. Our findings may help to identify patients early at a higher risk for an adverse outcome.

Automated cell count in body fluids: a review.

Body fluid cell counting provides valuable information for the diagnosis and treatment of a variety of conditions. Chamber cell count and cellularity analysis by optical microscopy are considered the gold-standard method for cell counting. However, this method has a long turnaround time and limited reproducibility, and requires highly-trained personnel. In the recent decades, specific modes have been developed for the analysis of body fluids. These modes, which perform automated cell counting, are incorporated into hemocytometers and urine analyzers. These innovations have been rapidly incorporated into routine laboratory practice. At present, a variety of analyzers are available that enable automated cell counting for body fluids. Nevertheless, these analyzers have some limitations and can only be operated by highly-qualified laboratory professionals. In this review, we provide an overview of the most relevant automated cell counters currently available for body fluids, the interpretation of the parameters measured by these analyzers, their main analytical features, and the role of optical microscopy as automated cell counters gain ground.

Recomendaciones preanalíticas para la medición del equilibrio ácido-base y los gases en sangre. Recomendación (2018) / Preanalytical recommendations in blood gas analysis

El análisis de gases en sangre es una prueba frecuentemente solicitada en diferentes ámbitos hospitalarios. La medida de los parámetros incluidos en este análisis puede verse afectada por un elevado número de condiciones preanalíticas y es responsabilidad del laboratorio garantizar que los resultados reflejan de forma segura el equilibrio ácido-base y el estado de oxigenación del paciente. Aunque muchas de estas condiciones son comunes al resto de las magnitudes del laboratorio, como la identificación correcta del espécimen, algunas son propias del análisis de gases debido a la estabilidad de las magnitudes incluidas en él. Este documento establece recomendaciones para el control de las condiciones preanalíticas y otras fuentes de error relacionadas con el análisis de gases en sangre, tales como las características de los materiales empleados para la toma de muestra (jeringas, agujas y anticoagulantes), tipo de muestra (sangre arterial, venosa y capilar «arterializada») y las condiciones para el manejo y transporte de la muestra, incluyendo la influencia del tiempo transcurrido entre la extracción y el análisis, la temperatura de la muestra durante el transporte y el transporte en sí

Blood gas analysis is a commonly ordered test in different hospital settings. The measurement of the parameters included in this analysis is vulnerable to a huge number of pre-analytical conditions. Laboratory staff are responsible for ensuring that these results accurately reflect the acid-base and oxygenation status of the patient. Despite many pre-analytical steps in blood gas testing being common to other laboratory tests, such as proper sample identification, others are particular for this determination, such as the stability of the analytes measured. The aim of this document is to provide recommendations for the control of the pre-analytical variables and other error sources related to blood gas analysis. These include the characteristics of the materials used to collect the blood samples (syringes, needles and anticoagulants), the sample types (arterial, venous and «arterialised» capillary blood), as well as the conditions for sample handling and transport, including the effect of the time between sampling and analysis, the temperature during transport, and the type of transport

Actuación del laboratorio en la atención a pacientes con infección por el virus Ébola. Experiencia en el Hospital Universitario La Paz / Clinical laboratory role in the management of patients with Ebola virus infection. Experience at La Paz University Hospital

El actual brote de enfermedad por el virus del Ébola en África Occidental fue considerado por la Organización Mundial de la Salud como una alerta sanitaria que constituye una urgencia de salud pública de importancia internacional. Los profesionales sanitarios debemos estar preparados estableciendo en nuestros hospitales procedimientos y protocolos de actuación basados en recomendaciones de instituciones sanitarias nacionales e internacionales con dos objetivos, garantizar la atención y manejo de pacientes con sospecha o confirmación de la enfermedad y la seguridad y salud de los trabajadores. El laboratorio clínico desempeña un papel fundamental y como tal ha de definir y establecer procedimientos específicos consensuados con los clínicos e integrados en los del propio centro, definiendo en primer lugar el modelo de organización que permita conseguir ambos objetivos. En esta revisión exponemos además nuestra experiencia basada en la atención a un paciente con la enfermedad confirmada que esperamos pueda servir de ayuda a otros centros (AU)

The ongoing Ebola virus outbreak in several countries in West Africa was considered by the World Health Organization as a public health emergency of international concern. Healthcare providers must be prepared in our hospitals by organizing specific procedures based on recommendations from national and international healthcare organizations. Two aims should be considered, appropriate medical care for patients with suspected or confirmed disease must be assured, as well as measures to prevent transmission to health-care workers. The clinical laboratory plays an important role and must define and establish its own procedures in agreement with clinicians and integrated into those of the institution, starting with the definition of the organization model in the laboratory to achieve those goals. Our experience based on the care of a patient with a confirmed case is presented, and it is hoped that it will help other colleagues to plan for Ebola (AU)

Efecto en pruebas de coagulación del procedimiento de extracción desde catéter reservorio vascular subcutáneo / Effects on blood coagulation tests when samples are drawn from implantable venous-access port systems

Introducción. En las Unidades de Extracción, cada vez es mayor el número de pacientes portadores de un catéter reservorio vascular subcutáneo (CRVS) que solicitan su utilización para la extracción de muestras para análisis, sustituyendo la venopunción convencional. El objetivo de este estudio fue evaluar si la obtención de la muestra de sangre a través de CRVS, a pesar de la utilización de un procedimiento de extracción específico, modifica los resultados de las pruebas de coagulación básicas. Material y métodos. Se estudiaron 10 pacientes que acudieron a la Unidad de Extracciones de nuestro hospital, atendidos de forma consecutiva por dos extractores experimentados. En cada paciente se obtuvieron 2 muestras de sangre, una mediante venopunción periférica y otra a través de CRVS, comparándose los resultados de las pruebas de coagulación (tiempo de protrombina-TP y fibrinógeno derivado, tiempo de tromboplastina parcial activado-TTPA y D-dímero). Resultados. En el caso del TTPA, se observaron diferencias estadística y clínicamente significativas entre las muestras obtenidas mediante venopunción y las obtenidas por el CRVS: las medias de los valores fueron 24,9s y 27,9s, respectivamente (p<0,05). No se encontraron diferencias estadísticamente significativas en el caso de TP, fibrinógeno y D-dímero. Conclusiones. La diferencia observada en los resultados para el TTPA entre las muestras obtenidas desde CRVS comparada con la extracción venosa periférica sugiere la recomendación, en estos casos, de efectuar venopunción periférica. El uso del dispositivo CRVS resulta cómodo para el paciente, pero no es recomendable en todos los casos ya que puede ser motivo de errores de laboratorio (AU)

Introduction. The number of patients with Implantable Venous-Access Port Systems (IVAPS) seen in Phlebotomy Outpatients, as well as requests for drawing blood samples through this system instead of conventional venepuncture, are continuously increasing. The aim of this study was to assess if drawing blood samples through IVAPS, despite using a specific procedure, may alter results of basic blood coagulation tests. Material and methods. We studied 10 patients with IVAPS, who came to Phlebotomy Outpatients at our hospital, and who were attended to by two nurses with experience in handling these devices. Two samples were obtained from each patient, one of them drawn through IVAPS, and the other by peripheral venepuncture, and the results for blood coagulation tests (Prothrombin Time-PT, PT derived Fibrinogen, Activated Partial Thromboplastin Time-APTT and D-Dimer) were evaluated. Results. Statistically and clinically significant differences were found, for APTT, between IVAPS and venepuncture: mean values were, respectively, 24.9s and 27.9s (P<.05). No other results (PT, PT derived Fibrinogen or D-Dimer) showed statistically significant differences. Conclusions. The difference observed in APTT results between samples drawn through IVAPS compared to samples obtained by venepuncture, suggests that peripheral venepuncture should be used in these patients. The use of IVAPS is convenient for the patient, but it is not always recommended, as it may lead to laboratory errors (AU)

Activación de la coagulación y fibrinólisis inducida por un ejercicio de larga duración (carrera de maratón) / Coagulation and fibrinolysis activation induced by continued physical exercise (marathon race)

Introducción y objetivos. Durante el ejercicio físico aumentan tanto el potencial coagulante como el fibrinolítico. La realización de ejercicio físico regular y moderado está asociada a una disminución de los eventos trombóticos, por el contrario, el ejercicio físico extenuante parece ser un desencadenante de eventos trombóticos especialmente en sujetos no entrenados. El objetivo del estudio es valorar los efectos de una carrera de maratón sobre diferentes parámetros de la actividad coagulativa y de la actividad fibrinolítica en individuos entrenados. Material y métodos. Se han estudiado 31 deportistas amateurs que han seguido un programa de entrenamiento de 4 meses y a los que se ha tomado muestras de sangre preejercicio, postejercicio y a las 24 y 72 horas para analizar las variaciones de el tiempo de protrombina, actividad de protrombina, tiempo de tromboplastina parcial activada, fibrinógeno, antitrombina III y dímero D, en respuesta a una carrera de maratón. Resultados. Las muestras postejercicio muestran un aumento de la actividad coagulativa y un marcado incremento de los niveles de dímero D (marcador de actividad fibrinolítica) asociados a una disminución de los niveles de fibrinógeno, probablemente por consumo. Las muestras de 24h presentan una disminución de los niveles de antitrombina III, posiblemente como consecuencia de su consumo durante la fase de ejercicio. Conclusiones. Los resultados obtenidos sugieren que en sujetos que han seguido una preparación física se produce un equilibrio general de los mecanismos hemostáticos (activación de la coagulación y fibrinólisis) tras el ejercicio físico de larga duración (AU)

Introduction and objectives. During physical exercise coagulation and fibrinolytic activities are increased. Moderate and regular exercise is associated with a decrease on thrombotic episodes. On the other hand exhausting physical exercise seems to be a trigger of thrombotic events, especially on non-trained subjects. The objective of this study is to investigate the effect of a marathon race on coagulation and fibrinolytic parameters on trained subjects. Material and methods. We studied 31 amateur athletes who had followed a training program for 4 months. Blood samples were collected before and after exercise and at 24hours and 72hours to test the effects of a marathon race on prothrombin time, prothrombin activity, activated partial thromboplastin time, fibrinogen, antithrombin III (AT3) and D dimer. Results. There was an increase in coagulation activity and a marked increase in D dimmer (marker of fibrinolytic activity) in post-exercise samples. There was also a decrease in fibrinogen levels, probably due to it has been used up during the exercise period. The 24 hour hours samples showed a decrease in AT3 levels, also as a result of AT3 consumption during the physical exercise. Conclusions. These data, suggests that in trained subjects, a general balance in haemostatic mechanisms is achieved (coagulation and fibrinolysis activation) with continued physical exercise (AU)

Revisión de valores críticos obtenidos en gasometrías realizadas en el lugar de asistencia al paciente / Review of critical values determined in Point-of-Care Testing units

Introducción. La detección y la comunicación rápida de resultados críticos es crucial para asegurar una adecuada atención al paciente. El Laboratorio de Urgencias (LABURG) lidera desde hace 10 años un proyecto de POCT (Point-of-care testing‘pruebas realizadas en el lugar de asistencia al paciente’) de gasometrías (con 17 analizadores descentralizados) acorde con recomendaciones de sociedades científicas (como la Sociedad Española de Bioquímica Clínica y Patología Molecular y la National Academy of Clinical Biochemistry). El objetivo de este estudio es realizar una revisión de los valores críticos en el año 2007 en los resultados de gases, electrólitos y metabolitos realizados en gasómetros en las POCT y en el LABURG. Material y métodos. A partir del sistema informático del laboratorio, se obtuvieron los resultados de las gasometrías, electrólitos y metabolitos realizados en las POCT y en el LABURG (nPOCT=201.746 y nLABURG=134.839 para gases; nPOCT=278.075 y nLABURG=651.016 para electrólitos y metabolitos). Como valores críticos para cada uno de los parámetros, se utilizaron las medias de los límites propuestos por Kost en su revisión de 2007. Se calcularon los porcentajes de resultados situados fuera de ellos en las POCT y en el LABURG. Resultados. Los porcentajes de valores críticos en las POCT y en el LABURG fueron respectivamente del 13,68 frente al 3,39% para gases, del 2,21 frente al 1,82% para electrólitos y del 6,66 frente al 1,37% para metabolitos. Los parámetros con más porcentaje de resultados críticos fueron la presión parcial de oxígeno, el lactato y el pH. Conclusiones. El mayor porcentaje de valores críticos en unidades de POCT respecto al del LABURG responde al tipo de pacientes que atienden estas unidades y apoya la necesidad de desarrollar proyectos para acercar estas determinaciones a la cabecera del paciente, proyectos liderados desde el laboratorio (AU)

Introduction. The identification and immediate notification of critical results is crucial to assure appropriate patient care. The Emergency Laboratory has led a POCT blood gases and electrolytes project for 10 years (17 decentralized analyzers), according to scientific societies recommendations (SEQC and NACB). The objective of this study is to review critical results of blood gases, electrolytes and metabolites determined in Point-Of-Care Testing (POCT) units and in the Emergency Laboratory (LABURG) in 2007. Material and methods. Using the laboratory information system, we obtained the results of blood gases, electrolytes and metabolites carried out in POCT and LABURG (nPOCT=201.746 and nLABURG=134.839 for gases and nPOCT=278.075 and nLABURG=651.016 for electrolytes and metabolites). As critical values for each parameter we used the mean of the limits proposed by Kost in 2007. The percentages of the results above or below those limits in POCT and LABURG were calculated. Results. The percentages of critical values in POCT and LABURG were: 13.68% vs. 3.39% for gases, 2.21% vs. 1.82% for electrolytes and 6.66% vs. 1.37% for metabolites. The parameters with more critical results were pO2, lactic acid and pH. Conclusions. The higher percentage of critical values in POCT units compared to LABURG is due to the number critical patients seen in these units, and it supports the importance of designing and developing new laboratory projects in order to carry out these determinations at the patient bedside (AU)