A study of pre-analytical errors in the clinical biochemistry laboratory at Victoria hospital, BMCRI, Bangalore

To categorize and calculate the percentage error of pre-analytical variables in the clinical biochemistry laboratory. Prospective observational study conducted for two months with documenting the frequency and type of pre-analytical errors occurring in venous samples. The total errors recorded were 1.31%. Insufficient volume followed by haemolysis amounted to a major proportion of errors. Continuous pre-analytical phase evaluation and taking corrective measures to make this phase error-free, have to be done.

Respondent-driven sampling: Advantages and disadvantages from a sampling method

This article summarizes the main elements, advantages, and disadvantages of Respondent-driven Sampling (RDS). Some criticisms regarding the feasibility of the inherent assumptions, their point estimators, and the obtained variances are pointed out. This article also comments on the problems observed in the quality of reports. Surveys using RDS should be methodologically sound as they are being applied to define priorities in health programs and develop national and international policies for financing service delivery, among other uses. However, there is considerable potential for bias related to implementation and analytical errors. There is limited empirical evidence on how representative the results obtained by RDS are, and the quest to improve the methodology is still in progress. Nevertheless, to have confidence in RDS results, we must verify that the social structure of the networks conforms to the assumptions required by the theory, that the sampling assumptions are reasonably fulfilled, and that the quality of the report is optimal, particularly for methodological and analytical items.

The Blood Lactate/Pyruvate Equilibrium Affair

The Lactate Shuttle hypothesis is supported by a variety of techniques including mass spectrometry analytics following infusion of carbon labeled isotopic tracers. However, there has been controversy over whether lactate tracers measure lactate (L) or pyruvate (P) turnover. Here we review the analytical errors, use of inappropriate tissue and animal models, failure to consider L and P pool sizes in modeling results, inappropriate tracer and blood sampling sites, and failure to anticipate roles of heart and lung parenchyma on L:P interactions. With support from magnetic resonance spectroscopy (MRS) and immunocytochemistry we conclude that carbon-labeled lactate tracers can be used to quantitate lactate fluxes.

DIFFERENT TYPES OF PRE ANALYTICAL ERRORS IN CLINICAL BIOCHEMISTRY LAB OF OSMANIA GENERAL HOSPITAL AND HOW TO MINIMIZE THEM.

OBJECTIVES:To study different types of pre-analytical errors in clinical biochemistry lab and how to minimize them. METHODOLOGY: An observational study was done at Department of Biochemistry , Osmania General Hospital for a period of 2 months from Aug 2020-Sep 2020.During this phase different types of errors were monitored. RESULTS: During a period of 2 months ,10000 samples were analyzed and among them 400 were found to be having an error. i.e. 4%. Among them Hemolyzed samples (37.5%), Lipemic samples(25%), Misidentification of samples(15%), Insufficient volume(12.5%) and Sample mixing (10%). CONCLUSION: Proper training to nursing staff and phlebotomist regarding use of vacutainer needles instead of syringes and time of collection of samples reduces the error of hemolysis and lipemia.Use of Barcode labels reduces the error of misidentification. Proper education regarding volume of blood to be collected and use of correct vacutainers reduces the error of insufficient volume and sample mixing.

Total IgE assessment in newborn umbilical cord blood

In this minireview we present important data on umbilical cord blood IgE antibodies in neonates and total IgE as a predictive biomarker for the development of allergen sensitization and atopic diseases later in life. Discussions regarding the methods for determining total IgE in serum or plasma from cord blood samples are focused on the main immunoassays used in different studies and clinical practice. The fluorescence enzyme immunoassay with anti-IgE covalently coupled to a capsulated cellulose polymer solid-phase is nowadays currently used to measure total IgE in human serum or plasma. The umbilical cord blood total IgE levels are quantitatively determined by using its low range assay. Specific and practical aspects regarding cord blood sampling, including specimen collection from the umbilical cord vessels and careful preparation of serum and plasma, alongside with knowledge of the principles of the immune methods used are important to avoid preanalytical and analytical errors and for obtaining accurate results of this risk biomarker for allergy.

Pre-analytical considerations in biomarker research: focus on cardiovascular disease

Clinical biomarker research is growing at a fast pace, particularly in the cardiovascular field, due to the demanding requirement to provide personalized precision medicine. The lack of a distinct molecular signature for each cardiovascular derangement results in a one-size-fits-all diagnostic and therapeutic approach, which may partially explain suboptimal outcomes in heterogeneous cardiovascular diseases (e.g., heart failure with preserved ejection fraction). A multidimensional approach using different biomarkers is quickly evolving, but it is necessary to consider pre-analytical variables, those to which a biological sample is subject before being analyzed, namely sample collection, handling, processing, and storage. Pre-analytical errors can induce systematic bias and imprecision, which may compromise research results, and are easy to avoid with an adequate study design. Academic clinicians and investigators must be aware of the basic considerations for biospecimen management and essential pre-analytical recommendations as lynchpin for biological material to provide efficient and valid data.

Chemometric Analysis of Serum Magnesium Calculations Using Mg-Xylidyl Blue-I Method Based on Molar Absorptivity

The concentration of magnesium is determined based on the absorbance of the Mg-Xylydil Blue-I complex solution use spectrophotometer. Based on the Lambert-Beer rule, the calculation of sample concentration is based on the formula A = Ԑ. b. C. Generally, the thickness of the cuvette (b) and the molar absorptivity (Ԑ) factor will be ignored because it is considered to have a fixed value, therefore the sample concentration is measured based on the ratio of the absorbance of the sample against the standard solution. However, the standard solution contains pure magnesium and has a different matrix than the sample matrix, so this condition can give analytical errors and lead to misinterpretation of the results. The purpose of this study was to determine the accuracy and the precision of serum magnesium calculation by the principle of the Mg- Xylydil Blue-I complex reaction based on molar absorptivity compared to the general method. This research uses comparative study design methods. The serum sample used was the patient's serum specimen who has a normal magnesium level. The results showed that the significance value of the paired t-test statistical was 0.000 (p < 0.05). The accuracy value (d%) of the calculation formula uses Ɛ is 0.00 and the precision value (CV%) is 0.53. While the accuracy value (d%) of the calculation formula without Ɛ is 0.00 and the precision value (CV%) is 0.38. Calculations based on molar absorptivity (Ɛ) can measure more significant serum magnesium than those calculated based on standard magnesium solutions.