Measurement Of Hemoglobin Concentration Research Articles

Volume kinetic analysis of 2 crystalloid fluid bolus rates in anesthetized cats.

To investigate the volume kinetic between 2 crystalloid fluid bolus rates in anesthetized cats. Prospective, randomized, dose-response study. University laboratory. Ten convenience-sample, purpose-bred domestic shorthair and medium hair cats. Intravenous 20mL/kg balanced crystalloid fluid over 10 (G10) or 40 (G40) minutes under anesthesia in a randomized order with at least a 5-day washout period. Serial measurements of hemoglobin (Hb) concentration and PCV were performed up to 60 minutes after conclusion of the fluid bolus. Plasma dilution was calculated with the Hb dilution method and fitted to a 2-compartment microconstant kinetic model using nonlinear mixed-effect models. The apparent central plasma volume (Vc) was similar between the 2 groups (G10: 81.2±23.8mL/kg and G40: 78.8±10.2mL/kg). The apparent peripheral volume (Vp) of G10 (4.81E+8±2.66E+8mL/kg) was twice that of G40 (2.36E+8±6.44E+7mL/kg). The rate constant from Vc to Vp (K12) of G10 (0.057±0.0196/min) was almost twice that of G40 (0.0302±0.00807/min). The elimination constant of G10 (0.0113±0.00672/min) was almost twice that of G40 (0.00534±0.00279/min). The peak plasma expansion was similar between G10 and G40 (20.7±1.9 and 19.1±5.1mL/kg). Area under the curve for plasma dilution versus time of the first 90 minutes from the beginning of the boluses was not statistically different between G10 and G40. The volume expansion over time was not different likely due to the slow elimination. The plasma dilution to crystalloid bolus between subjects is varied in anesthetized cats. Clinicians should consider the slow elimination and return of crystalloid fluid from the Vp to Vc when prescribing fluid therapy in anesthetized cats.

Prevalence and contributors to anaemia among children aged 6 to 59 months in Kyangwali Refugee settlement, Western Uganda: a cross-sectional study

BackgroundAnaemia is a major cause of morbidity among children under five years in Uganda. However, its magnitude among refugee populations is marginally documented. In this study, the prevalence and contributors to anaemia among children 6 to 59 months in Kyangwali refugee settlement in Western Uganda was determined.MethodsThis was a cross-sectional study that was carried out among 415 mother- child dyads at Kwangwali refugee settlement. Anaemia was determined by measuring haemoglobin concentration using the HaemoCue method, while nutritional status was examined using standard World Health Organisation (WHO) nutritional indices. Data abstraction forms, pretested questionnaires and face to face interviews were used to collect patient data. Associations between the independent variables and anaemia were examined using modified Poisson regression with robust standard errors. In all statistical tests, a P- value of < 0.05 was considered as significant.ResultsThe proportion of children with anaemia was 49.2% (95% CI: 44.4–53.9). Anaemia was 1.4 times (95% CI = 1.13–1.82; p = 0.003) more prevalent among wasted children than the normal children. The prevalence of anaemia was also higher among underweight children than those with normal weight (aPR = 1.37, 95% CI = 1.11–1.70; p = 0.004). Additionally, the prevalence of anaemia was higher among children of birth order of 6 or above (aPR = 2.00, 95% CI = 1.22–3.29; p = 0.006), while anaemia prevalence was lower among children whose mothers’ had attained secondary level of education (aPR = 0.19, CI = 0.04–0.98; p = 0.048) and those who fed on fish (aPR = 0.75, 95% CI = 0.57–0.99; p = 0.039) and meals prepared with oils and fats (aPR = 0.70, 95% CI = 0.51–0.97; p = 0.029). There was no significant relationship between anaemia occurrence and the household dietary diversity score.ConclusionsAbout half of the study children were found to be anaemic. The most significant contributors to anaemia in the study population were malnutrition, maternal education, feeding practices and birth order. The study findings suggest need of screening of children for anaemia at all nutritional clinics, promotion of education, addressing barriers to sustainable food supply and accessibility of nutrient-dense foods, treating anaemia in children alongside other micronutrient deficiencies and addressing the nutritional needs of multiparous mothers in refugee communities.

Prevalence of suspected anemia in Japanese young children determined using non-invasive hemoglobin measurements: an observational study.

Recently, non-invasive hemoglobin measurement (SpHb) using Pulse CO-Oximeter Rad-67™ Spot-check (Rad-67) has been validated although anemia diagnosis typically relies on blood hemoglobin concentration measurement. In this large-scale survey of Japanese children aged 1-5 years, we evaluated SpHb distribution to understand the prevalence of suspected anemia, and further examined the relationship between SpHb and background factors. Children were recruited from large retail stores in Japan between November 2022 and August 2023. SpHb was measured by nutritionists or registered dietitians using Rad-67. 4133 participants were included and stratified by age and sex. The prevalence of children below the WHO threshold value for anemia was found to be 5.2% in total (ranging between 2.6-7.8% in subgroups). Mean SpHb values increased with age, and were higher in boys. Age and sex were independently related to SpHb. Overall, this study shows that approximately 3-8% of young children in Japan are suspected to be anemic.

Anemia-associated smaller brain volume and sex differences: a cross-sectional study of magnetic resonance imaging in brain health checkups.

Anemia is a risk factor for dementia development. However, few studies have examined the relationship between brain volume and anemia. This study aimed to analyze the association between anemia and brain volume using magnetic resonance imaging data from brain health checkups. Participants underwent brain health checkups between January 2015 and March 2022. Blood samples were collected to measure hemoglobin concentrations and mean corpuscular volumes. The modified Mini-Mental State Examination (MMSE) was used to evaluate cognitive function. Magnetic resonance images were analyzed using voxel-based Morphometry to evaluate the overall patterns of brain volume. After extracting the principal components (PCs) from PC analysis, we investigated their association with MMSE scores and anemia. This study included 1,029 participants and identified principal components, representing smaller volume in the frontal lobe (PC1), and smaller volume in the limbic system to the temporal lobe (PC2). A higher PC2 score was significantly associated with a lower MMSE score. Male participants with anemia had smaller bilateral PC1 volumes and left hippocampal volumes, and female participants with anemia had smaller bilateral PC2 volumes and hippocampus volumes. PC2 may represent the extent of disease affecting limbic system volume, such as Alzheimer's disease. Our results suggest that anemia may be associated with smaller volumes in the limbic system, especially in women. Further studies are required to determine which type of anemia is more strongly correlated with smaller brain volumes.

Comparison of haemoglobin concentration measurements using HemoCue-301 and Sysmex XN-Series 1500: A survey among anaemic Gambian infants aged 6-12 months.

In low-income countries, point-of-care photometers are used in the screening and management of anaemia in individuals, but also in the assessment of population iron status when evaluating efficacy of intervention studies or public health interventions. We aimed to evaluate the accuracy of a commonly used photometer, HemoCue-301, in determining haemoglobin concentration among anaemic children aged 6-12 months in a field setting in rural Africa. This report concerns a secondary analysis of data from Gambian infants being screened for an ongoing randomized controlled trial. In those found to be anaemic by HemoCue-301, haemoglobin concentration was measured by Sysmex XN-1500, an automated haematology analyser that was used as a reference. Passing-Bablok regression analysis was used to estimate the regression constant (systematic deviation between two measurement methods that remain consistent across the range of measurements) and proportional bias (systematic deviation between two measurement methods that change in magnitude relative to the value being measured). Analysis was based on 227 participants. There was strong evidence of absolute bias among moderately anaemic participants (haemoglobin concentration at 8.0g/dL) (absolute bias: 1.12g/dL; 95% CI: 0.91 to 1.37g/dL; proportional bias: 14.0%; 95% CI: 11.4% to 17.1%) in haemoglobin concentrations measured by HemoCue-301 compared to those measured by Sysmex XN-Series1500. Bias was marginal at haemoglobin concentration of 11.0g/dL (absolute bias: -0.08g/dL; 95% CI: -0.18 to 0.07g/dL; proportional bias: -7.3%; 95% CI: -6.5% to 0.6%). Haemoglobin measurements by HemoCue-301 seem substantially biased in participants with haemoglobin less than 8.0g/dL.

Does induction or augmentation of labor increase the risk of postpartum hemorrhage in pregnant women with anemia? A multicenter prospective cohort study in India.

To investigate whether induction/augmentation of labor in pregnant women with anemia increases the risk of postpartum hemorrhage (PPH) and whether this risk varied by indications for labor induction/augmentation and by anemia severity in pregnancy. In a prospective cohort study of 9420 pregnant women from 13 hospitals across India, we measured hemoglobin concentrations at recruitment (≥28 weeks of gestation) and blood loss after childbirth during follow-up and collected clinical information about PPH. Clinical obstetric and childbirth information at both visits were extracted from medical records. Anemia severity in the third trimester was categorized using hemoglobin concentrations (no/mild anemia: hemoglobin ≥10 g/dL; moderate: hemoglobin 7 to 9.9 g/dL; severe: hemoglobin <7 g/dL), while PPH was defined based on blood loss volume (vaginal births: ≥500 mL or cesarean sections: ≥1000 mL) and clinical diagnosis. Indications for labor induction/augmentation were classified as clinically indicated and elective as per guidelines. We performed multivariable modified Poisson regression analyses to investigate the associations of anemia severity and indications for labor induction/augmentation, including their interaction, with PPH, adjusted for potential confounders. PPH was associated with anemia but not with indications for labor induction/augmentation. However, there was a significant interaction between the two factors in relation to PPH (P = 0.003). Among pregnant women with severe anemia, a higher risk of PPH was associated with elective (adjusted risk ratio, 3.44 [95% confidence interval, 1.29-9.18]) but not with clinically indicated (adjusted risk ratio, 1.22 [95% confidence interval, 0.42-3.55]) labor induction/augmentation. No associations were observed among pregnant women with no/mild and moderate anemia. The risk of PPH is higher in women who have moderate-severe anemia in late pregnancy. Induction/augmentation of labor is generally safe for women with anemia, but it can increase the risk of PPH in women with severe anemia if performed electively.

Inconsistency in ferritin reference intervals across laboratories: a major concern for clinical decision making.

Iron deficiency anemia is a significant global health concern, diagnosed by measuring hemoglobin concentrations in combination with plasma ferritin concentration. This study investigated the variability in ferritin reference intervals among laboratories in the Netherlands and examined how this affects the identification of iron-related disorders. Ferritin reference intervals from 52 Dutch ISO15189-certified medical laboratories were collected. Ferritin, hemoglobin and mean corpuscular volume data of non-anemic apparently healthy primary care patients, measured by four laboratory platforms (Beckman, Abbott, Siemens, and Roche), were collected (n=397,548). Median ferritin levels were determined per platform, stratified by sex and age. The proportion of ferritin measurements outside of the reference interval was calculated using the reference intervals from the 52 laboratories (using a total of n=1,093,442 ferritin measurements). Lastly, ferritin data from 3,699 patients as captured in general practitioner (GP) data from the PHARMO Data Network were used to assess the variation of abnormal ferritin measurements per GP. Median plasma ferritin concentrations were approximately four times higher in men and twice as high in postmenopausal women compared to premenopausal women. Moreover, there are substantial differences in the median plasma ferritin concentration between the four platforms. However, even among laboratories using the same platform, ferritin reference intervals differ widely. This leads to significant differences in the percentages of measurements classified as abnormal, with the percentage of ferritin measurements below the reference limit in premenopausal women ranging from 11 to 53 %, in postmenopausal women from 3 to 37 %, and in men from 2 to 19 %. The percentage of ferritin measurements above the reference limit in premenopausal women ranged from 0.2 to 11 %, in postmenopausal women from 3 to 36 % and in men from 7 to 32 %. The lack of harmonization in ferritin measurement and the disagreement in plasma ferritin reference intervals significantly impact the interpretation of the iron status of patients and thereby the number of iron disorder diagnoses made. Standardization or harmonization of the ferritin assays and establishing uniform reference intervals and medical decision limits are essential to reduce the substantial variability in clinical interpretations of ferritin results.

Novel single-cell measurements suggest irreversibly sickled cells are neither dense nor dehydrated

In sickle cell anemia, deoxygenation causes erythrocytes to distort, while reoxygenation permits them to recover a normal biconcave disk shape. Irreversibly sickled cells (ISCs) remain distorted when reoxygenated and have been thought to have among the highest intracellular hemoglobin concentrations of the sickle red cell population and therefore the greatest vulnerability to vasoocclusion. Using a new optical method, which we describe, we have made precise measurements of the intracellular hemoglobin concentration, and intracellular O2 saturation, of ISCs, as well as oxygenated sickle cells with a normal biconcave disc shape, and cells with shapes distorted by the sickle fibers they contain. This method also provides good estimates of cell volumes, and hemoglobin per red cell. The concentration distribution of the ISCs is found to be similar to normal, discoid cells. Average ISC volumes exceed their discoid counterparts, with a much broader distribution, arguing against dehydration as their origin. The concentration distribution of the polymer-laden sickled cells is significantly higher in mean value, and their volume distributions indicate some dehydration. Previous assumptions about ISCs may have thus been colored by the presence of sickle cells that did contain polymer, and true ISCs may be much more benign than once thought, which underscores the importance of accurate measurement on individual cells. This method could be used to follow changes in individual cell properties under various specific perturbations, and where characterization by flow cytometry is infeasible.

Study on the association between malnutrition, early childhood caries and caries activity among children aged 3–5 years

BackgroundThis study aims to investigate the association between malnutrition and early childhood caries (ECC) and caries activity among children aged 3–5 years, in order to provide a theoretical basis for preventing and blocking ECC and improving malnutrition.MethodsChildren aged 3–5 years from six kindergartens in Zhao Xian, China were enrolled in this study. The decayed, missing, filled teeth (dmft) of all children were examined and recorded. The Cariostat method was used to detect dental caries activity, collect anthropometric data and measure haemoglobin concentration. Parents were asked to complete a questionnaire on the general characteristics and oral health behaviour of the participants. The “Growth Standards for Chinese Children Under 7 Years Old” was used to assess the nutritional status of all participating children. Wilcoxon rank sum test and multivariate logistic regression analysis were used to analyse and evaluate the relationship between ECC, caries activity and malnutrition.ResultsA total of 635 children who met the criteria were included in this study. After adjusting for confounding factors, logistic regression showed that the risk of ECC was significantly increased in underweight children compared with normal children (OR = 5.43, P < 0. 05); compared with normal children, the risk of ECC decreased in overweight and obese children (OR = 0.31, P < 0.001); underweight children had higher caries severity than normal weight children, and the difference was statistically significant (OR = 2.69, P < 0. 05); stunted children had higher caries severity than normal weight children and the difference was statistically significant (OR = 2.28, P < 0.05); underweight was positively associated with caries activity and the association was statistically significant (OR = 2.33, P < 0. 05); stunting was positively associated with caries activity and the association was statistically significant (OR = 2.1, P < 0.05); overweight and obesity were negatively associated with caries activity and the association was statistically significant (OR = 0.61, P < 0.05).ConclusionsThe risk of ECC among children aged 3–5 years was positively associated with undernutrition and negatively associated with overnutrition. The severity of ECC among children aged 3–5 years was positively associated with undernutrition. The caries activity among children aged 3–5 years was positively associated with undernutrition and negatively associated with overnutrition.

Emerging Evidence and Critical Issues with the Use of Single-Drop Capillary Blood for the Measurement of Hemoglobin Concentration in Population-Level Anemia Surveys

Accurate and precise measurement of hemoglobin concentration is critical for reliable estimations of anemia prevalence at the population level. When systematic and/or random error are introduced in hemoglobin measurement, estimates of anemia prevalence might be significantly erroneous and, hence, limit their usefulness. For decades, single-drop capillary blood has been the most common blood source used for the measurement of hemoglobin concentration in surveys, especially in low-income and middle-income countries. In this study, we highlight historical and emerging evidence that single-drop capillary blood introduces a high degree of random error (variability) to hemoglobin estimates, leading to less reliable estimates of anemia prevalence at the population level. At present, the best practice is to collect and use venous blood for measurement of hemoglobin with an automated hematology analyzer, following standard operating procedures and quality assurance measures. Where use of an automated analyzer is not possible, the analysis of venous blood in a point-of-care hemoglobinometer by trained phlebotomists or specimen collectors should be considered. A forthcoming systematic review will provide additional evidence on the accuracy and precision of single-drop capillary blood for hemoglobin assessment. In the meantime, we raise caution when using single-drop capillary blood for hemoglobin measurement as it can result in inaccurate hemoglobin estimates and less reliable anemia prevalence estimates.

A simple physical model for simulation and design magneto-plethysmograph in application non-invasive hemoglobin measurement

The magneto-plethysmograph method is a combination of magnetic field and sensors used to detect changes in blood flow pulsation. However, to detect the magnetic properties of blood related to hemoglobin concentration, physical modeling and simulation are required. This approach involves designing simulations using magnetic field equations and magnetic susceptibility, where a permanent magnet is placed on the surface of blood vessels, and sensors based on giant magnetoresistance are placed at a distance r. The design originates from a simple approach involving the magnetization and detection of Fe atoms in hemoglobin. Parameters involved include the magnetic susceptibility of oxyhemoglobin and deoxyhemoglobin, with an external magnetic field exceeding 1 Tesla. From the physical modeling and simulation, graphs are obtained depicting the influence of hemoglobin concentration on the number of Fe atoms and its magnetization. This enables the design of non-invasive hemoglobin measurement sensor devices. The uniqueness of this simple physical model and simulation lies in its ability to produce specially designed device models for measuring hemoglobin concentration. This differs from other research focusing on blood flow pulse measurements; the results of this study provide new insights into the benefits of simple physics equations that can be developed for medical diagnostic research and device development.

Real-time non-invasive hemoglobin prediction using deep learning-enabled smartphone imaging

BackgroundAccurate measurement of hemoglobin concentration is essential for various medical scenarios, including preoperative evaluations and determining blood loss. Traditional invasive methods are inconvenient and not suitable for rapid, point-of-care testing. Moreover, current models, due to their complex parameters, are not well-suited for mobile medical settings, which limits the ability to conduct frequent and rapid testing. This study aims to introduce a novel, compact, and efficient system that leverages deep learning and smartphone technology to accurately estimate hemoglobin levels, thereby facilitating rapid and accessible medical assessments.MethodsThe study employed a smartphone application to capture images of the eye, which were subsequently analyzed by a deep neural network trained on data from invasive blood test data. Specifically, the EGE-Unet model was utilized for eyelid segmentation, while the DHA(C3AE) model was employed for hemoglobin level prediction. The performance of the EGE-Unet was evaluated using statistical metrics including mean intersection over union (MIOU), F1 Score, accuracy, specificity, and sensitivity. The DHA(C3AE) model’s performance was assessed using mean absolute error (MAE), mean-square error (MSE), root mean square error (RMSE), and R^2.ResultsThe EGE-Unet model demonstrated robust performance in eyelid segmentation, achieving an MIOU of 0.78, an F1 Score of 0.87, an accuracy of 0.97, a specificity of 0.98, and a sensitivity of 0.86. The DHA(C3AE) model for hemoglobin level prediction yielded promising outcomes with an MAE of 1.34, an MSE of 2.85, an RMSE of 1.69, and an R^2 of 0.34. The overall size of the model is modest at 1.08 M, with a computational complexity of 0.12 FLOPs (G).ConclusionsThis system presents a groundbreaking approach that eliminates the need for supplementary devices, providing a cost-effective, swift, and accurate method for healthcare professionals to enhance treatment planning and improve patient care in perioperative environments. The proposed system has the potential to enable frequent and rapid testing of hemoglobin levels, which can be particularly beneficial in mobile medical settings.Trial RegistrationThe clinical trial was registered on the Chinese Clinical Trial Registry (No. ChiCTR2100044138) on 20/02/2021.

Evaluation of folliculogenesis and oxidative stress parameters in type 1 diabetes mellitus women with different glycemic profiles.

Despite enormous advances in diabetes treatment, women with type 1 diabetes mellitus (DM) still experience delayed menarche, menstrual irregularities, fewer pregnancies, and a higher rate of stillbirths compared to women without the disease. Due to the fact that type 1 DM occurs at a young age, the preservation of reproductive health is one of the most important goals of treatment. The aim of this study was to evaluate the relationship between different glycemic profiles and changes in the pro-oxidant-antioxidant balance and ovarian follicular apparatus in reproductive-age patients with type 1 DM. We examined 50 reproductive-age (19-38 years) women with type 1 DM with a disease duration of at least ten years. Carbohydrate metabolism was assessed with the continuous glucose monitoring (CGM) system and glycated hemoglobin (HbA1c) concentration measurement. CGM was performed using the FreeStyle Libre flash glucose monitoring system (Abbott Diabetes Care, Witney, UK). In each patient, malondialdehyde level, catalase activity and 3-nitrotyrosine level in the blood serum were determined. To assess the ovarian function, we measured the ovarian volume, the antral follicle count, and the serum levels of anti-Müllerian hormone and follicle-stimulating hormone. All patients were divided into four groups (glucotypes) based on the CGM results. Group 1 included type 1 DM patients with satisfactory compensation of carbohydrate metabolism; group 2 consisted of patients with frequent hypoglycemic conditions and pathological glucose variability; group 3 included individuals with prolonged hyperglycemic conditions and maximum HbA1c levels; and group 4 comprised patients with the glycemic profile characterized by all the presented types of dysglycemia (intermittent glycemia). We revealed a negative correlation between serum catalase activity and time of hypoglycemic conditions in patients with type 1 DM based on the CGM results (rs = -0.47, p < 0.01). In group 4 (intermittent glycemia), patients demonstrated the lowest serum catalase activity and increased serum 3-nitrotyrosine level, while in group 3, women with chronic hyperglycemia (HbA1c 8.4 [8.1; 9.9]%; 68 [65; 85] mmol/mol) had a moderate change in antioxidant defense and oxidative stress parameters. Correlation analysis of ovarian volume, the antral follicle count, and the serum anti-Müllerian hormone level in type 1 DM women with different glycemic profiles established a negative relationship (rs = -0.82, p < 0.05) between the antral follicle count and glucose variability in group 1, a positive relationship (rs = 0.68, p < 0.05) between ovarian volume and glucose variability in group 2, and a positive relationship (rs = 0.88, p < 0.05) between ovarian volume and time of hypoglycemic conditions, which, according to the CGM results, amounted to a critical value of 57.5 [40.0; 82.0]%. The data obtained indicate the relationship between the ovarian volume, serum anti-Müllerian hormone level, the antral follicle count and oxidative stress parameters not only in patients with hyperglycemia, but also in those with hypoglycemic conditions, as well as with pathological glucose variability.

Tibetans exhibit lower hemoglobin concentration and decreased heart response to hypoxia during poikilocapnia at intermediate altitude relative to Han Chinese.

High-altitude populations exhibit distinct cellular, respiratory, and cardiovascular phenotypes, some of which provide adaptive advantages to hypoxic conditions compared to populations with sea-level ancestry. Studies performed in populations with a history of high-altitude residence, such as Tibetans, support the idea that many of these phenotypes may be shaped by genomic features that have been positively selected for throughout generations. We hypothesize that such traits observed in Tibetans at high altitude also occur in Tibetans living at intermediate altitude, even in the absence of severe sustained hypoxia. We studied individuals of high-altitude ancestry (Tibetans, n = 17 females; n = 12 males) and sea-level ancestry (Han Chinese, n = 6 females; n = 10 males), both who had been living at ∼1300m (∼4327ft) for at least 18 months. We measured hemoglobin concentration ([Hb]), hypoxic ventilatory response (HVR), and hypoxic heart rate response (HHRR) with end-tidal CO2 (PetCO2) held constant (isocapnia) or allowed to decrease with hypoxic hyperventilation (poikilocapnia). We also quantified the contribution of CO2 on ventilation and heart rate by calculating the differences of isocapnic versus poikilocapnic hypoxic conditions (Δ /ΔPetCO2 and ΔHR/ΔPetCO2, respectively). Male Tibetans had lower [Hb] compared to Han Chinese males (p < 0.05), consistent with reports for individuals from these populations living at high altitude and sea level. Measurements of ventilation (resting ventilation, HVR, and PetCO2) were similar for both groups. Heart rate responses to hypoxia were similar in both groups during isocapnia; however, HHRR in poikilocapnia was reduced in the Tibetan group (p < 0.03), and the heart rate response to CO2 in hypoxia was lower in Tibetans relative to Han Chinese (p < 0.01). These results suggest that Tibetans living at intermediate altitude have blunted cardiac responses in the context of hypoxia. Hence, only some of the phenotypes observed in Tibetans living at high altitude are observed in Tibetans living at intermediate altitude. Whereas blunted cardiac responses to hypoxia is revealed at intermediate altitudes, manifestation of other physiological adaptations to high altitude may require exposure to more severe levels of hypoxia.

Evaluating the impact of skin perfusion on cerebral hemoglobin concentration measurement using modified Beer-Lambert and Spatially Resolved Spectroscopy: Preliminary findings

Evaluating the impact of skin perfusion on cerebral hemoglobin concentration measurement using modified Beer-Lambert and Spatially Resolved Spectroscopy: Preliminary findings

The relationship between menorrhagia, iron deficiency, and anaemia in recreationally active females: An exploratory population based screening study

ObjectivesIron deficiency, anaemia, and menorrhagia – or heavy menstrual bleeding – are interrelated conditions that are highly prevalent and commonly underrecognised in exercising females of reproductive age. This study utilised a screening tool to identify risk factors and symptoms associated with heavy menstrual bleeding, iron deficiency, and anaemia in this population. DesignAn observational, cross sectional survey study was employed. Methods1042 active females (aged 18–65) completed a comprehensive screening questionnaire and 887 (85 % compliance) provided a fingerprick blood sample for haemoglobin (Hb) concentration measurement. Women that presented as anaemic (defined as a [Hb] < 120 g/L) or deemed to be at risk of iron deficiency (120 < [Hb] < 130 g/L) were asked to complete follow-up blood tests to screen for iron studies. ResultsAverage [Hb] was 134.2 ± 12.1 g/L, with 94 individuals considered anaemic (10.6 %). Of the sample, 104 underwent follow-up blood tests; 51 (~49 %) presented with iron deficiency (defined as ferritin <30 μg/L). Based on survey responses, 274 (30.9 %) participants were determined to have heavy menstrual bleeding. Those presenting with heavy menstrual bleeding were younger, exercised fewer hours per week, and were more likely to have a history of iron deficiency or anaemia (all p < 0.05). Participants reporting a history of anaemia or iron deficiency were more likely to have heavy menstrual bleeding (anaemia: 39.7 %; iron deficiency; 36.9 %; both p < 0.05). ConclusionsIn this cohort of exercising females of reproductive age, the prevalence of anaemia was 10.6 %. There is a strong association between heavy menstrual bleeding and a self-reported history of iron deficiency and anaemia. Greater awareness of heavy menstrual bleeding and its relationship with iron deficiency and anaemia is needed in this population. Non-invasive screening should be conducted to raise awareness and further understand the associated risk factors and symptomatology.

A novel measure to summarize blood transfusion practice during critical illness.

Large-scale observational studies have summarized transfusion practice using traditional measures of central tendency (e.g., the mean hemoglobin concentration at the time of transfusion). However, the mean hemoglobin concentration fails to identify specific hemoglobin concentration thresholds that drive practice. In the following brief report, we propose a novel measure of "practice discontinuity" that identifies specific practice-defining hemoglobin thresholds. We used the PINC AI Database (2016-2022) to identify adult patients admitted to an intensive care unit with at least one hemoglobin concentration measurement. For each day that hemoglobin was measured, we identified whether the patient received a red blood cell transfusion using hospital charge codes. We defined the "practice discontinuity" measure as the hemoglobin concentration at which there was the largest increase in transfusion use going from a higher to an incrementally lower hemoglobin concentration. We also calculated the mean and median pretransfusion hemoglobin concentrations. We identified 1,298,367 patients and 4,905,839 patient-days for inclusion. RBC transfusion occurred in a total of 530,654 (10.8%) patient-days. The overall pre-transfusion mean and median hemoglobin concentrations were 8.4 and 8.0 g/dL, respectively. The practice discontinuity measure identified 7.0 g/dL as the hemoglobin concentration at which transfusion use increased the most, from 46.6% of patient-days at a concentration of 7.0 g/dL to 74.8% of patient-days at a concentration of 6.9 g/dL. We propose that future studies of red blood cell transfusion practice consider inclusion of the practice discontinuity measure to more fully summarize clinical practice.

Prevalence of anaemia among adolescent girls (10-19 years) in India: A systematic review and meta-analysis.

Background Anaemia is a serious public health problem. It is the second-commonest contributing factor to years lost by adolescents to disability and death. Targeting adolescent girls will allow a window of opportunity to correct their nutritional health and improve their obstetric outcomes. Studies in India have reported varying prevalence rates of anaemia among adolescent girls. Hence, we did a systematic review and meta-analysis of community-based studies to obtain a comprehensive pooled estimate of the prevalence of anaemia among adolescent girls in India. Methods We did a systematic electronic search in PubMed, Embase, Cochrane Library and Google scholar to retrieve community-based studies that reported the prevalence of anaemia among adolescent girls (10-19 years) in India, without any date or language restriction. To estimate the pooled prevalence and heterogeneity, the random-effects model and I2 statistical methods were used. We did subgroup analyses based on geographical region, study setting, method used to measure haemoglobin concentration, and year of publication. Results We included 35 studies in this meta-analysis comprising 152 640 participants. The pooled prevalence of anaemia among adolescent girls was 65.7% (95% CI 59.3%- 71.9%). There was significant heterogeneity between the studies (I2 99.6%; p<0.001). Conclusion There is a high prevalence of anaemia among adolescent girls in India. While all regions of the country have a high prevalence, tribal areas need special attention. Targeted actions need to focus on the identification of determinants of anaemia apart from iron supplementation.

Temperature and hypoxia‐driven shifts in Daphnia interspecific competition

AbstractPrevious research has shown that elevated temperature and environmental hypoxia are associated with a reduced representation of larger‐bodied species in communities of ectotherms, suggesting their competitive disadvantage resulting from increased oxygen demands and limited oxygen availability. To investigate this, we conducted a comparative analysis of two pairs of competing zooplankton species: Daphnia galeata (smaller‐bodied) and Daphnia pulex (larger‐bodied), as well as D. pulex (smaller‐bodied) and Daphnia magna (larger‐bodied). We monitored their population dynamics under different oxygen concentrations and temperatures, and additionally measured hemoglobin concentration in the latter pair. Contrary to expectations, the results demonstrated that the larger‐bodied species outcompeted the smaller‐bodied ones in all experimental treatments involving the first pair of species. In the second pair, elevated temperature favored the smaller‐bodied species, while environmental hypoxia had the opposite effect. The competitive advantage of D. pulex under elevated temperature likely stemmed from their ability to allocate energy from somatic growth to reproduction, as indicated by the increased number of reproducing females. Conversely, the competitive advantage of D. magna under environmental hypoxia may be attributed to their ability to reallocate energy from reproduction to somatic growth, as indicated by lower reproductive effort and greater plasticity in hemoglobin production. These findings indicate that elevated temperature and hypoxia can independently and jointly influence interspecific competitive abilities by impacting the pace of life. However, the numerical dominance of smaller‐sized species in warm and hypoxic zooplankton communities cannot be explained by their enhanced competitive abilities resulting from a more favorable oxygen supply demand balance.

Impact of market-based home fortification with micronutrient powder on childhood anemia in Bangladesh: a modified stepped wedge design.

Anemia poses a significant public health problem, affecting 1.6 billion people and contributing to the loss of 68.4 million disability-adjusted life years. We assessed the impact of a market-based home fortification program with micronutrient powder (MNP) called Pushtikona-5 implemented by Bangladesh Rural Advancement Committee (BRAC) on the prevalence of anemia among children aged 6-59 months in Bangladesh. We used a modified stepped wedged design and conducted three baseline, two midline, and three endline surveys to evaluate the Pushtikona-5 program implemented through three BRAC program platforms. We interviewed children's caregivers, and collected finger-prick blood samples from children to measure hemoglobin concentration. We also collected data on coverage of Pushtikona-5 and infant and young child feeding (IYCF) practices. We performed bivariate and multivariable analysis and calculated adjusted risk ratios (ARRs) to assess the effect of program outcomes. A total of 16,936 households were surveyed. The prevalence of anemia was 46.6% at baseline, dropping to 32.1% at midline and 31.2% at endline. These represented adjusted relative reductions of 34% at midline (RR 0.66, 95%CI 0.62 to 0.71, value of p <0.001) and 32% at endline (RR 0.68, 95%CI 0.64 to 0.71, value of p <0.001) relative to baseline. Regarding MNP coverage, at baseline, 43.5% of caregivers surveyed had heard about MNP; 24.3% of children had ever consumed food with MNP, and only 1.8% had consumed three or more sachets in the 7 days preceding the survey. These increased to 63.0, 36.9, and 4.6%, respectively, at midline and 90.6, 68.9, and 11.5%, respectively, at endline. These results show evidence of a reduction in the prevalence of anemia and an improvement in coverage. This study provides important evidence of the feasibility and potential for impact of linking market-based MNP distribution with IYCF promotion through community level health workers.