Evaluation of the use of non-invasive hemoglobin measurement in early childhood

A Noninvasive Approach to Assess the Prevalence of and Factors Associated With Anemia Risk in Malaysian Children Under Three Years of Age: Cross-Sectional Study

Background

Anemia remains a significant public health concern with adverse effects among children. Noninvasive screening assessments enable the early detection and prompt treatment of anemia. However, there is limited literature on the use of such screening assessments.

Objective

The study aimed to assess the prevalence of and factors associated with being at risk of anemia among Malaysian children aged ≥6 months to ≤36 months by using a noninvasive hemoglobin assessment.

Methods

This was a cross-sectional study (from July to December 2022) of outpatient Malaysian children, aged ≥6 months to ≤36 months, who were selected from five maternal-and-child health clinics by convenience sampling. At risk of anemia was defined as a total hemoglobin level of <12 g/dL, measured using the Masimo Rad-67, a noninvasive screening device for total hemoglobin levels. The χ2 and multiple logistic regression analyses were used to assess the prevalence and factors associated with being at risk of anemia, using R-Studio (version 4.0.0).

Results

The study included 1201 participants, of whom 30% (95% CI 28-33) were at risk of anemia. Children aged 6-12 months (210/364, 57.7%, P<.001), those of Asian Malay race (238/364, 65.4%, P<.05), those residing in the Klang district (123/371, 33.9%, P<.05), those born via a normal vaginal delivery (275/364, 75.5%, P<.05), those without a family history of thalassemia (284/364, 78.0%, P<.05), and those with lower weight-for-age Z scores (P<.05) were associated with being at risk of anemia. Children aged 6-12 months (adjusted odds ratio=1.73; 95% CI 1.34-2.24) had higher odds of being at risk of anemia compared to children aged >12-36 months. However, weight-for-age (adjusted odds ratio=0.88; 95% CI 0.80-0.98) was associated with lower odds of being at risk of anemia.

Conclusions

The current study revealed a substantial prevalence of Malaysian children being at risk of developing anemia. The study results therefore imply a need for more community education and awareness on anemia, including nutrition education, as well as targeted community screening to enable the early detection and prompt treatment of anemia cases. Anemia reduction strategies in Malaysia should consider the highlighted factors indicative of higher risk of anemia.

Prevalence of suspected anemia in Japanese young children determined using noninvasive hemoglobin measurements: an observational study

Recently, noninvasive spot 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. Four thousand one hundred thirty-three participants were included and stratified by age and sex. The prevalence of children below the World Health Organization threshold value for anemia was found to be 5.2% in total (ranging between 2.6% and 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.

Comparison of a non-invasive point-of-care measurement of anemia to conventionally used HemoCue devices in Gambella refugee camp, Ethiopia, 2022

Annual surveys of refugees in Gambella, Ethiopia suggest that anemia is a persistent public health problem among non-pregnant women of reproductive age (NP-WRA, 15-49 years). Measurement of anemia in most refugee camp settings is conducted using an invasive HemoCue 301. We assessed the accuracy and precision of a non-invasive, pulse CO-oximeter in measuring anemia among NP-WRA in four Gambella refugee camps. We conducted a population-representative household survey between November 7 and December 4, 2022. Hemoglobin (Hb) concentration was measured by HemoCue 301, using capillary blood, and Rad-67, a novel non-invasive device. We collected four measurements per participant: two per device. We calculated Rad-67 bias and precision of Hb measurements and sensitivity and specificity of detecting anemia. Of the 812 NP-WRAs selected, 807 (99%) participated in the study. Anemia was detected in 39% of NP-WRA as classified by the Rad-67 compared with 47% of NP-WRA as classified by the HemoCue 301. Average bias of Rad-67 measurements was 1.1 ± 1.0 SD g/dL, using HemoCue 301 as a comparator. Absolute mean difference between the first and second measurements was 0.9 g/dL (95% CI 0.8, 0.9) using the Rad-67, compared with 0.6 g/dL (95% CI 0.5, 0.6) using the HemoCue 301. The Rad-67 had 49% sensitivity and 70% specificity for detecting anemia, compared with the HemoCue 301. The Rad-67 can be a useful tool for anemia screening; however, lower accuracy and precision, and poor sensitivity suggest it cannot immediately replace the HemoCue 301 in the study area.

Evaluation of Non-Invasive Hemoglobin Monitoring in Perioperative Patients: A Retrospective Study of the Rad-67TM (Masimo)

Background: Hemoglobin (Hb) is a crucial parameter in perioperative care due to its essential role for oxygen transport and tissue oxygenation. Accurate Hb monitoring allows for timely interventions to address perioperative anemia and, thus, prevent morbidity and mortality. Traditional Hb measurements rely on invasive blood sampling, which significantly contributes to iatrogenic anemia and poses discomfort and increased infection risks. The advent of non-invasive devices like Masimo's Rad-67™, which measures Hb using pulse CO-oximetry (SpHb), offers a promising alternative. This study evaluates the accuracy of SpHb compared to clinical standard blood gas analysis (BGA) in perioperative patients. Methods: This retrospective study analyzed 335 paired Hb measurements with an interval <15 min between SpHb and BGA in the operating theater and post-anesthesia care unit of a university hospital. Patients experiencing hemodynamic instability, acute bleeding, or critical care were excluded. Statistical analysis included Bland-Altman plots and Pearson correlation coefficients (PCCs) to assess the agreement between SpHb and BGA. Potential confounders, e.g., patient age, skin temperature, sex, perfusion index (PI), and atrial fibrillation, were also analyzed. Results: The bias of the SpHb compared to BGA according to Bland-Altman was 0.00 g/dL, with limits of agreement ranging from -2.70 to 2.45 g/dL. A strong correlation was observed (r = 0.79). Overall, 57.6% of the paired measurements showed a deviation between the two methods of ≤±1 g/dL; however, this applied to only 33.3% of the anemic patients. Modified Clark's Error Grid analysis showed 85.4% of values fell within clinically acceptable limits. Sex was found to have a statistically significant, but not clinically relevant, effect on accuracy (p = 0.02). Conclusions: The Rad-67TM demonstrates reasonable accuracy for non-invasive SpHb, but exhibits significant discrepancies in anemic patients with overestimating low values. While it offers potential for reducing iatrogenic blood loss, SpHb so far should not replace BGA in critical clinical decision-making.

Accuracy of noninvasive total haemoglobin measurement for detecting anaemia in infants: a cross-sectional study in a well-child care clinic, Khon Kaen, Thailand

OBJECTIVE

Infants are at a high risk of developing anaemia, which can arise from various causes, including inappropriate feeding practices. However, few infants attend anaemia screening programmes due to poor cooperation and being time-consuming. This study evaluated the accuracy of noninvasive total haemoglobin (Hb) spot-check monitoring as part of anaemia screening in healthy infants, compared with the conventional laboratory method.

DESIGN

A cross-sectional study was conducted using a consecutive sampling technique.

SETTING

The study was carried out at the Well-Child Clinic, Khon Kaen University, Thailand.

PARTICIPANTS

Healthy, full-term infants aged 6-12 months who were scheduled for vaccination. Spectrophotometric haemoglobin (SpHb) was measured using Masimo Rad-67 with Rainbow DCI-mini Sensor. These values were compared with conventional laboratory analysis (HbLab) performed on the same day.

PRIMARY AND SECONDARY OUTCOME

Differences between Hb values using the two methods were analysed using the Bland-Altman method. Sensitivity, specificity and positive and negative predictive values (PPV and NPV) for detecting anaemia were determined. Anaemia was defined as HbLab of <11.0 g/dL.

RESULTS

A total of 104 infants, with a median age of 9.6 (IQR 9.3, 10.9) months, were included. The prevalence of anaemia, defined by HbLab, was 38.46%. The mean SpHb was 12.20±1.10 g/dL, while the mean HbLab was 11.19±1.21 g/dL. A moderate positive correlation was observed (r=0.575, p<0.001). Bland-Altman analysis of SpHb vs HbLab showed an estimated bias of 1.007 g/dL with a 95% limit of agreement ranging from -1.091 to 3.104 g/dL. The mean bias was 1.635 g/dL (-0.617 to 3.887) in the anaemic group and 0.614 g/dL (-0.964 to 2.192) in the nonanaemic group. Using the SpHb cut-off point of <13.0 g/dL, the sensitivity and specificity of SpHb to detect anaemia were 95.0% and 35.9%, with PPV and NPV of 48.1% and 92.0%, respectively.

CONCLUSION

A noninvasive tool for measuring Hb, with moderate sensitivity and NPV, may provide utility for initial screening to reduce unnecessary venipuncture in infants. However, its limited specificity and PPV necessitate confirmatory testing through conventional laboratory methods for accurate diagnosis. Depending on the context and available resources, it has potential to complement existing diagnostic processes, particularly in settings where rapid and noninvasive screening is prioritised.

TRIAL REGISTRATION NUMBER

Thai Clinical Trials Registry (TCTR20210816002).

Non-invasive hemoglobin measurement using optical method

The measurement of Hemoglobin (Hb) by the non-invasive method is gaining popularity. The system, consisting of a photodiode is placed in between a Red (630 nm) and an IR (940 nm) LED, along with the signal conditioning circuits. 10 healthy male (8) and female (2) volunteers in the age group between 21 and 24 were recruited for this study. During measurement, the fingertip of a volunteer was placed on the measurement pad. Visible and IR lights are switched ON one after the other. The optical absorbance of the blood component in the arteries was detected by the photodiode using the reflectance method. The current generated was converted into voltage and was processed to remove the noise associated with the signal. From this, the concentration of Hb of the volunteers was determined. On the same day they were taken to the clinical laboratory and Hb values were obtained by the standard invasive method. Hemoglobin values obtained from the two methods were compared and an accuracy of 96.31 % and correlation coefficient value of 0.932405 was achieved. From the Bland -Altman plot, the results obtained are within the confidence interval of 95 %. The error of 3 % can be reduced further by employing sophisticated signal conditioning techniques. The proposed non-invasive method took only a few seconds to find the hemoglobin concentration than the invasive lab test. This method can accelerate the decision-making process in emergency situations.

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

BACKGROUND

Accurate 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.

METHODS

The 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.

RESULTS

The 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).

CONCLUSIONS

This 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 REGISTRATION

The clinical trial was registered on the Chinese Clinical Trial Registry (No. ChiCTR2100044138) on 20/02/2021.

What are the risk factors for death among children with pneumonia in low- and middle-income countries? A systematic review

Background

Knowledge of the risk factors for and causes of treatment failure and mortality in childhood pneumonia is important for prevention, diagnosis, and treatment at an individual and population level. This review aimed to identify the most important risk factors for mortality among children aged under ten years with pneumonia.

Methods

We systematically searched MEDLINE, EMBASE, and PubMed for observational and interventional studies reporting risk factors for mortality in children (aged two months to nine years) in low- and middle-income countries (LMICs). We screened articles according to specified inclusion and exclusion criteria, assessed risk of bias using the EPHPP framework, and extracted data on demographic, clinical, and laboratory risk factors for death. We synthesized data descriptively and using Forest plots and did not attempt meta-analysis due to the heterogeneity in study design, definitions, and populations.

Findings

We included 143 studies in this review. Hypoxaemia (low blood oxygen level), decreased conscious state, severe acute malnutrition, and the presence of an underlying chronic condition were the risk factors most strongly and consistently associated with increased mortality in children with pneumonia. Additional important clinical factors that were associated with mortality in the majority of studies included particular clinical signs (cyanosis, pallor, tachypnoea, chest indrawing, convulsions, diarrhoea), chronic comorbidities (anaemia, HIV infection, congenital heart disease, heart failure), as well as other non-severe forms of malnutrition. Important demographic factors associated with mortality in the majority of studies included age <12 months and inadequate immunisation. Important laboratory and investigation findings associated with mortality in the majority of studies included: confirmed Pneumocystis jirovecii pneumonia (PJP), consolidation on chest x-ray, pleural effusion on chest x-ray, and leukopenia. Several other demographic, clinical and laboratory findings were associated with mortality less consistently or in a small numbers of studies.

Conclusions

Risk assessment for children with pneumonia should include routine evaluation for hypoxaemia (pulse oximetry), decreased conscious state (e.g. AVPU), malnutrition (severe, moderate, and stunting), and the presence of an underlying chronic condition as these are strongly and consistently associated with increased mortality. Other potentially useful risk factors include the presence of pallor or anaemia, chest indrawing, young age (<12 months), inadequate immunisation, and leukopenia.