土井 洋輝

BACKGROUND: Capillary blood collection offers a less burdensome alternative to venous sampling and may improve access to laboratory testing in resource-limited settings. However, manual procedures can yield pre-analytical variation, resulting in the need for skilled personnel. To address these limitations, we developed a prototype device that automates fingertip blood collection. METHODS: The device automatically punctures a fingertip using a disposable lancet, applies intermittent compression to the fingertip using a cuff, sequentially collects blood into two microtubes, and completes hemostasis with gauze. We evaluated the device in 58 healthy volunteers aged 20-60 years by comparing capillary blood collected with the device to venous blood via standard phlebotomy. Paired samples were processed and analyzed under hospital laboratory quality control. Measurements included 8 CBC parameters, glucose and HbA1c in whole blood, 3 electrolytes, and 15 biochemical analytes in serum. Agreement was assessed using Deming regression, and bias with 95% confidence intervals at medical decision levels (MDLs) was calculated. RESULTS: Most analytes exhibited biases within the allowable limits defined by the Clinical Laboratory Improvement Amendments (CLIA), except for white blood cell count (WBC), potassium (K), lactate dehydrogenase (LD), and glucose. Compared with the BD MiniDraw™, which involves manual finger compression, our device showed greater biases in WBC and K, likely due to the margination effect and hemolysis, respectively-both enhanced by stronger compression. CONCLUSION: The device demonstrated acceptable analytical performance for most parameters. Optimizing compression strength and duration may reduce bias. Automated capillary collection could support decentralized testing and reduce phlebotomy workload.

BACKGROUND: Packed red blood cells (PRBC) are stored at 2°C-6°C to ensure quality. Improper temperature control during PRBC transport reduces the quality of downstream blood products and wastes PRBC units. This study evaluated the suitability of the BioBox LAB10 for in-hospital PRBC transport. METHODS: Temperatures of the box interior and simulated formulation were measured to assess cooling capabilities. Quality was evaluated by measuring red blood cell count, haemoglobin concentration, haematocrit, pH, potassium concentration, and ATP concentration of PRBC samples. The storage capacity, size, weight, and cost of the BioBox was compared with that of the ATR700. RESULTS: The BioBox cooled to ≤6°C within 14 min. PRBC temperature remained ≤6°C for approximately 19 h. None of the quality parameters, including ATP concentration, differed significantly between samples stored in the BioBox or in a refrigerator. The BioBox is smaller, lighter, and 84% less expensive than the ATR700, with an equivalent storage capacity. CONCLUSIONS: The BioBox effectively maintains temperature and PRBC quality during transport and provides a practical solution for in-hospital transport of blood for transfusion owing to its compact, lightweight design, and affordability.

PURPOSE: This study aimed to evaluate the blood-sampling performance of an automatic fingertip blood-sampling system with a fingertip vessel-puncture function (FBS-FV) and to examine the relationship between sampled blood volume and fingertip blood-vessel image features. METHODS: To obtain a consistent blood volume for testing, the FBS-FV selects and punctures near a large blood based on fingertip blood-vessel imaging and promotes bleeding by alternately pressing and releasing the fingertip. A blood-sampling experiment was conducted with 18 participants (men and women in their 20 to 60 s). Puncture accuracy, blood volume, and image features (relative brightness at the puncture position V and brightness change due to compression C) were analyzed. Multiple regression was applied to assess the predictive value of V and C for blood volume. RESULTS: (1) The deviation between the target and actual puncture positions was less than 1 mm, indicating high accuracy. (2) The proportion of blood samples obtained using the FBS-FV that exceeded the target volume (650 μL) was 42%, which was lower than in a previous experiment where the puncture position selected by the FBS-FV was manually punctured and blood was sampled. (3) Multiple regression analysis using image features V and C yielded coefficients of determination of 0.64 and 0.41 for high- and low-volume groups, respectively, suggesting that the possibility of predicting blood volume using these variables. CONCLUSION: The FBS-FV demonstrated precise puncture performance and potential for predicting blood volume using image features. Further optimization of the FBS-FV's compression control might improve the consistency of blood sampling.