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Introduction: Specimens suspected of errors related to low hemoglobin or changes in hemoglobin beyond that of clinically explained variations during hospital stays are frequently redrawn under the auspices that they are contaminated. When lack of an indwelling IV eliminates contamination as a possibility, evaluation of the specimen between the time of collection and testing should occur., Methods: As part of a quality improvement project, we investigated the impact of sedimentation on collected blood specimens not immediately transferred to their respective tubes from a syringe. Each syringe of blood was allowed to stand in a vertical position on the transfer device. After 10 min, each syringe was divided into a bottom half and top half into fresh blood tubes, with half of the samples inverted prior to division. Samples were then analyzed for complete blood count., Results: These results indicate that implementing an inversion of collected specimens prior to transferring will effectively eliminate variations related to sedimentation of blood., Conclusions: Results highlight the importance of specimen handling after collection, including appropriate mixing to avoid erroneous results caused by erythrocyte sedimentation. Mixing syringes before transferring blood to collection tubes ensures a uniform sample and accurate result., (© Association for Diagnostics & Laboratory Medicine 2024. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

HBA1c testing is a health indicator for pre-diabetes identification or diabetes detection and follow-up. Simplifying collection and transport of blood samples for HBA1c measurement remains of great interest. Capillary dried blood spots (DBS) sampling has been proposed as a potential alternative to classical whole blood (WB) venipuncture, however, international analytical and clinical validation of DBS use is necessary before implementation. We aimed in the present study to assess the performance, clinical acceptability and analyte stability (at 20-25°C, +4°C, -20°C) of DBS sampling method compared to WB. The study enrolled 40 participants. Obtained WB were applied to Whatman 903 protein blotting paper. Prepared DBS samples were compared to WB samples kept in EDTA collection tubes using the Bio-Rad D-10 IEX-HPLC instrument. Statistical analysis was carried out using IBM SPSS Statistics 29.0.1.0 and NCSS v23-0-2 software programs. Agreement (LCCC = 0.982; limits of agreement M ± 1.96SD: -0.45; 0.48) and correlation (PCC = 0.990) between DBS and WB results were excellent. Also, repeatability (CV = 1.13) and clinical conformity (K = 0.80) of the values obtained on DBS were found to be highly satisfactory. Our results clearly showed that DBS sampling could be an efficient alternative to WB venipuncture for HBA1c measurement.

Background: Rasburicase retains activity at room temperature (RT), so specimens collected for uric acid-level monitoring require cooling protocols. Our objective was to determine if we could ease these preanalytical requirements to improve compliance while maintaining accuracy., Methods: Fifty pairs of specimens were transported and stored either on ice or at RT. All were tested at 3 time points postcollection: immediately upon arrival to the laboratory (approximately 45 min), 90, and 135 min., Results: Uric acid concentrations are not clinically significantly different in RT or iced specimens, as long as specimens are tested within approximately 45 min postcollection. There was a negative bias in uric acid levels in a subset of specimens if they were held at RT and tested at 90 min (-9.1%) and 135 min (-17.5%). Specimens tested within 2 rasburicase half-lives postinfusion have an additional 24% decrease in uric acid levels if kept at RT for 90 min. Specimens from patients given a 6 mg dose had an 18% decrease in uric acid concentration compared to a 3 mg dose., Conclusions: Laboratories that can test uric acid levels rapidly after specimen collection may be able to validate alternative preanalytical methods to transporting and testing on ice., (© Association for Diagnostics & Laboratory Medicine 2024.)

Background: There is growing interest in the use of capillary blood sampling (CBS) for testing biochemical analytes owing to the advantages it offers including home surveillance of chronic conditions. In this study, we aimed to determine whether the use of CBS was a viable and feasible method for testing total prostate-specific antigen (TPSA) concentrations in men with prostate disease., Methods: Men with known prostate disease were recruited from a urology clinic where they were being treated or followed up. Samples were collected in serum separating tubes by the finger-prick method using validated devices. Simultaneously, venous blood was collected by venipuncture. We used validated immunoassays on both the Roche (Cobas 801) and Beckman (DXi) platforms to measure TPSA., Results: In total, 66 adult men between 26 and 64 years of age were tested. Across the concentration range of normal (0.3 µg/L) to pathological (314 µg/L), the results between CBS and venous samples were highly comparable and correlated (r = 0.997). The average bias was 0.112 µg/L or 1.07% and was not significant (P = 0.274). Overall, there was no apparent proportional or constant bias observed. Our data showed that TPSA may be stable in CBS stored at ambient temperature for up to 8 days in the samples tested using either the Roche or Beckman assays., Conclusions: This feasibility study shows that CBS and venous samples are highly correlated and there was negligible bias. Further validation work is now required for the measurement of TPSA in CBS and determining outcomes in men with prostate disease., (© Association for Diagnostics & Laboratory Medicine 2024. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Background: Multianalyte machine learning (ML) models can potentially identify previously undetectable wrong blood in tube (WBIT) errors, improving upon current single-analyte delta check methodology. However, WBIT detection model performance has not been assessed in a real-world, low-prevalence context. To estimate real-world positive predictive values, we propose a methodology to assess WBIT detection models by evaluating the impact of missing data and by using a "low prevalence" validation data set., Methods: We trained a range of model specifications using various predictors in a pediatric setting. We assessed the top-performing model on a modified, "low prevalence" validation data set across a range of probability thresholds. Model performance was also compared to a pre-positive patient identification (pre-PPID) dataset., Results: An Extreme Gradient Boosting (XGBoost) model with minimal preprocessing performed the best for both complete blood count with differential white cell count (CBC with Diff) tests (accuracy 0.9715) and complete blood count without differential white cell count (CBC without Diff) tests (accuracy 0.9647). Assessment on a downsampled, "low prevalence" validation data set resulted in estimated positive predictive values ranging from 0.01 to 0.67 (CBC with Diff) and 0.01 to 0.75 (CBC without Diff), depending on the probability threshold chosen. A comparison of prospective performance to PPID data demonstrated a large decrease in estimated WBIT errors., Conclusions: We find that ML models can accurately predict WBITs in a primarily pediatric setting. Evaluating model performance across a range of probability thresholds minimizes the number of false positives while still providing added safety benefits. The decrease in estimated WBITS post-PPID implementation shows the potential safety benefits of a WBIT model for hospitals not using PPID when collecting laboratory specimens., (© Association for Diagnostics & Laboratory Medicine 2025. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

Central vascular access devices (CVADs) have become an important focus for safe practice in some patients. The aim of this study was to develop a reliable and valid knowledge questionnaire of blood sampling via CVADs for registered nurses by using both classical test theory (CTT) and Rasch analysis. A cross-sectional study was conducted, and the questionnaire was completed by 445 participants. CTT and Rasch analysis were used to measure the psychometric properties of the questionnaire. The final questionnaire consisted of 23 items. CTT analysis revealed acceptable internal reliability with Cronbach's alpha of 0.825 and content validity index (I-CVI = 0.99, S-CVI/UA = 0.925). Rasch analysis was conducted using a dichotomous scale, and the final 23-item questionnaire is unidimensional. The person reliability index was 0.69 with an item reliability index of 0.97. The test-retest reliability was excellent, with an intraclass correlation coefficient of 0.964. This questionnaire demonstrated a unidimensional structure and good psychological properties and was clinically meaningful for registered nurses to test their knowledge of blood sampling via CVADs. The findings represent a useful beginning for further analysis of the questionnaire in larger samples internationally., Competing Interests: Conflict of interest: The authors declare no conflicts of interest., (Copyright © 2025 Infusion Nurses Society.)

Introduction: Fetal scalp blood sampling (FSBS) can be used as an adjunctive test, in the presence of a pathological intrapartum fetal heart rate trace, to provide evidence of fetal acidaemia. The role of FSBS remains controversial, this study evaluates the diagnostic accuracy of FSBS at determining various adverse neonatal outcomes., Method: A retrospective cohort analysis of FSBS undertaken < 1 h from birth in a single UK centre in 2016 and 2017. An FSBS pH of < 7.20 was abnormal. Adverse outcomes were: low umbilical cord artery (UCA) pH (<7.20), neonatal acidaemia (UCA pH < 7.05), and 5-minute Apgar score < 7. Regression was performed to adjust for potential confounding variables. Receiver operator characteristic (ROC) curves were calculated and test accuracy, including sensitivity and specificity were determined, for an abnormal FSBS pH and adverse neonatal outcomes., Results: Data from 407 births occurring ≤ 60 min from FSBS were analysed. To predict neonatal acidaemia, FSBS had an area under the ROC (AUROC) of 0.77 (95 % CI 0.65, 0.88). To predict low Apgar scores, FSBS had an AUROC of 0.80 (95 % CI 0.70, 0.90). In general, an FSBS pH of < 7.20 has low sensitivity and high specificity for neonatal acidaemia (28.6 % and 85.5 % respectively) and for low Apgar scores (38.1 %, 90.82 %)., Discussion: As FSBS has high specificity for adverse neonatal outcomes, it could be used to exclude asphyxia as it has a high NPV. Further research is required to evaluate whether other means of FSBS assessment, e.g. lactate, have better diagnostic test accuracy., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Alexander Heazell reports financial support was provided by Tommy’s. If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025 The Authors. Published by Elsevier B.V. All rights reserved.)

Background: Alternative means of blood sampling continue to grow due to the scarcity of phlebotomists and the need for person-centered care. It is crucial to consistently support these alternative blood sampling innovations with scientific evidence to guarantee the quality of care, especially when implementing for instance Lateral Upper-arm Blood Collection (LUBC) for use at home. Knowledge gaps remain in how to quantify imprecision introduced by the collection method and its impact on clinical use., Methods: We developed the Six Sigma analysis for alternative Sampling methods, including sampling method-induced imprecision, accuracy and precision, called σ 3 -methodology (S3). We performed a two-step verification using σ 3 -methodology for LUBC TAP® II, which included fourteen routine clinical analytes. We used venipuncture as the gold standard., Results: The biggest source of imprecision for all analytes was sampling method-induced imprecision, which, for the first time, was quantified, resulting in a varying effect on the clinical usability. TAP® II showed acceptable analytical performance for ALP, bilirubin, HDL-cholesterol, CRP and sodium. Unacceptable analytical performance was found for ALT, AST, cholesterol, creatinine, GGT, HbA1c, potassium, LDH and triglycerides., Conclusion: Alternative blood sampling innovations hold promise for advancing diagnostic care, aiming to deliver accessible decentralised sample collection at home that does not require phlebotomist involvement. However, sampling method-induced imprecision should not be overlooked in the performance assessment to guarantee responsible development that will contribute to the success and desirable societal impact of alternative sampling technologies., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Monitoring clofazimine blood concentrations is crucial for preventing treatment failure in patients with Multidrug-resistant Tuberculosis (MDR-TB). Volumetric Absorptive Microsampling (VAMS) offers a practical alternative to Conventional Venous Sampling (CVS), enabling remote sampling. Samples collected via VAMS can be conveniently transported to laboratories via courier, enhancing accessibility and patient compliance. In this study, we developed and validated an analytical method for quantifying clofazimine in whole blood collected using VAMS. The study compared the performance and cost-effectiveness of VAMS with CVS. A total of 55 matched finger-prick VAMS and CVS samples were obtained from 39 MDR-TB patients and analyzed using validated UPLC-MS/MS assays. Clofazimine concentrations collected via VAMS and CVS were compared using Passing-Bablok regression, while bias and overall agreement were evaluated through Bland-Altman analysis. Passing-Bablok regression revealed no significant constant difference between VAMS and CVS (95% CI slope: 0.7627-0.9573; 95% CI intercept: -0.02141-0.06482), but systematic difference of 13% lower clofazimine concentrations was observed in VAMS compared to plasma. Bland-Altman analysis demonstrated moderate agreement, with mean plasma/VAMS ratio of 0.9457 (95% CI: 0.88358-1.00775) and 95% Limits of Agreement (LoA) ranging from 0.4956 (95% CI: 0.38881-0.60230) to 1.3858 (95% CI: 1.28903-1.50252). Although statistically significant bias was identified, applying correction factors could improve interchangeability between the two techniques. Furthermore, VAMS was more cost-effective than CVS, with approximate cost difference of 4.45 USD per sample. These findings suggest that VAMS sampling has the potential to replace CVS for routine clinical monitoring of clofazimine, offering a more accessible and economical approach., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2025. Published by Elsevier B.V.)

Complement analysis necessitates strict control of pre-analytical blood handling, including time, temperature, and additives. Here, we compared complement function and activation status across five different serum preparations and two plasma preparations. Serum was collected from ten healthy volunteers using glass tubes without additives, tubes with a silica clot activator (with or without a gel separator), and tubes containing thrombin (with or without a gel separator). Plasma was collected in the presence of EDTA or the thrombin inhibitor lepirudin. Serum and plasma aliquots were snap-frozen in liquid nitrogen and stored at -80 °C. Complement functional analysis was performed using Wieslab and Hycult Biotech pathway-specific assays. Complement activation was determined by quantifying specific activation markers: C1s/C1-INH, MASP-1/C1-INH, C3bc, C3bBbP, and sC5b-9. All serum samples exhibited increased complement activation compared to EDTA and lepirudin plasma, with serum tubes containing thrombin and gel separators showing the highest levels of complement activation. However, normal complement function was observed in all serum preparations, indicating that the complement activation and consumption that occurred did not affect complement functional analysis. While all tested serum tubes provided accurate functional activity, the type of tube and the presence of additives like thrombin and gel separators significantly influenced the degree of complement activation. We recommend preparing functionally active serum either in glass tubes or in silica clot activator tubes, and avoiding gel separators. For complement activation studies, lepirudin plasma is preferable over serum due to its complement functional capacity, low level of complement activation, and lack of excessive hemostatic activation., Competing Interests: Declaration of competing interest R.J.M.G.E.B. and E.J.M.T. are employees of Hycult Biotech. L.I.A., D.J.S., T.E.M., and P.H.N. have nothing to declare., (Copyright © 2024. Published by Elsevier B.V.)

Capillary blood collection presents advantages such as reduced invasiveness over venous serum for syphilis diagnosing. This study aimed to compare diagnostic accuracy between capillary and venous blood samples for syphilis diagnosis. Individuals aged ≥ 18 years were included in a cross-sectional study. Syphilis screening was done using Rapid tests (RT) followed by collection of serum capillary and venous samples for VDRL and TPHA test. Sensitivity, specificity, and Kappa coefficient were calculated. Of 191 participants, 115 RT + and 76 RT-. Diagnostic properties did not significantly differ between capillary and venous samples. Capillary VDRL showed 99% sensitivity and 100% specificity, mirroring TPHA results. Furthermore, there was significant agreement between sample types for both serological tests (p < 0.001). Capillary sampling offers comparable diagnostic accuracy to venous collection, regardless of serum quality. Capillary sampling holds promise, particularly in developing countries and large-scale testing initiatives., Competing Interests: Declarations. Competing interests: The authors declare no competing interests., (© 2025. The Author(s).)

Objectives: Laboratory testing, crucial for medical diagnosis, has 3 phases: preanalytical, analytical, and postanalytical. This study set out to demonstrate whether automating tube labeling through artificial intelligence (AI) support enhances efficiency, reduces errors, and improves outpatient phlebotomy services., Methods: The NESLI tube-labeling robot (Labenko Informatics), which uses AI models for tube selection and handling, was used for the experiments. The study evaluated the NESLI robot's operational performance, including labelling time, technical problems, tube handling success, and critical stock alerts. The robot's label readability was also tested on various laboratory devices. This research will contribute to the field's understanding of the potential impact of automated tube-labeling systems on laboratory processes in the preanalytical phase., Results: NESLI demonstrated high performance in labeling processes, achieving a success rate of 99.2% in labeling parameters and a success rate of 100% in other areas. For nonlabeling parameters, the average labeling time per tube was measured at 8.96 seconds, with a 100% success rate in tube handling and critical stock warnings. Technical issues were promptly resolved, affirming the NESLI robot's effectiveness and reliability in automating the tube-labeling processes., Conclusions: Robotic systems using AI, such as NESLI, have the potential to increase process efficiency and reduce errors in the preanalytical phase of laboratory testing. Integration of such systems into comprehensive information systems is crucial for optimizing phlebotomy services and ensuring timely and accurate diagnostics., (© The Author(s) 2024. Published by Oxford University Press on behalf of American Society for Clinical Pathology. All rights reserved. For commercial re-use, please contact reprints@oup.com for reprints and translation rights for reprints. All other permissions can be obtained through our RightsLink service via the Permissions link on the article page on our site—for further information please contact journals.permissions@oup.com.)

The Working Group Preanalytical Phase of the European Federation of Clinical Chemistry and Laboratory Medicine advises suppressing haemolysis-sensitive tests when haemolysis is clinically significant, as improper specimen handling can rupture red blood cells, increasing potassium levels. Thus, a correctly repeated blood sample should show lower potassium levels than a haemolysed one. This study aimed to determine the prevalence of haemolysed samples with potassium levels below the reference range and whether this predicts hypokalemia in repeated collections. From March 2022 to March 2024, 396,640 non-haemolysed samples (H-index < 2 UA) were analyzed. Samples with an H-index ≥ 2 AU were classified as haemolysed, and potassium values were suppressed. Warnings were issued for haemolysed samples with potassium below the reference range (3.4-4.5 mmol/L), advising new sample collection. Twenty-five (0.01%) repeat samples were taken within 24 hours of a previously haemolysed sample with low potassium. Severe and moderate hypokalemia were more common in these repeats, with severe hypokalemia (≤2.5 mmol/L) found in 48% of repeat tests, compared to 0.3% in all samples. Though rare, a decrease in potassium in haemolysed samples often precedes hypokalemia diagnosis. Implementing a simple and cost-effective LIS algorithm to alert clinicians could potentially reduce diagnosis and treatment time.

The preservation of blood capital is essential in many clinical situations. The laboratory, by optimizing the tubes to be sampled, provides valuable assistance in this context. The aim of this work is to study the possibility of analyzing an expanded panel of usual biochemistry and automated hormonal parameters on a single tube: heparin lithium with separator gel. Thirty-two blood samples were analyzed for a usual biochemistry panel (ALT, uric acid, albumin, AST, bicarbonates, total bilirubin, calcium, chloride, creatine kinase, creatinine, iron, GGT, glucose, haptoglobin, LDH, magnesium, PAL, inorganic phosphorus, potassium, total protein, sodium, triglycerides, urea) and a hormonal automated panel (cortisol, hGH, insulin, prolactin, free T3, free T4, TSH, B12 vitamin). For each panel, the sample was taken from the laboratory's classically recommended tube (lithium heparin without separator gel for usual biochemistry and plain without separator gel for automated hormonology) and from the single tube to be tested (heparin lithium with separator gel). The results of the recommended tubes were compared to those of the single tube, statistically and then with regard to the clinical impact. Significant differences were observed between the recommended tube and the single tube for: AST, calcium, chloride, GGT, LDH and phosphorus. Apart from LDH, no parameter revealed a clinically significant difference. Plasma collected on lithium heparin with separator gel is suitable for the determination of a wide range of biochemistry parameters, except for LDH, which should need an adaptation of its usual values with regard to the considered tube.

Objective . Arterial sampling for PET imaging often involves continuously measuring the radiotracer activity concentration in blood using an automatic blood sampling system (ABSS). We proposed and validated an external delay and dispersion correction procedure needed when a change in flow rate occurs during data acquisition. We also measured the external dispersion constant of [ 11 C]CURB, [ 18 F]FDG, [ 18 F]FEPPA, and [ 18 F]SynVesT-1. Approach . External delay and dispersion constants were measured for the flow rates of 350, 300, 180, and 150 ml h -1 , using 1-minute-long rectangular inputs ( n = 10; 18 F-fluoride in saline). Resulting constants were used to validate the external delay and dispersion corrections ( n = 6; 18 F-fluoride in saline; flow rate change: 350 to 150 ml h -1 and 300 to 180 ml h -1 ); constants were modelled to transition linearly between flow rates. Corrected curves were assessed using the percent area-under-the-curve (AUC) ratio and a modified model selection criterion (MSC). External delay and dispersion constants were measured for various radiotracers using a blood analog (i.e., similar viscoelastic properties). Main results . ABSS outputs were successfully corrected for external delay and dispersion using our proposed method accounting for a change in flow rate. AUC ratio reduced from ∼10% for the uncorrected 350-150 ml h -1 output (∼6% for the 300-180 ml h -1 ) to < 1% after correction when compared to true input (511 keV energy window); approx. 5-fold increase in MSC. Assuming an internal dispersion constant of 5 s, the dispersion constant (internal + external) for [ 11 C]CURB, [ 18 F]FDG, [ 18 F]FEPPA, and [ 18 F]SynVesT-1 was 13, 9, 16, and 10 s, respectively. Significance . This study presented an external delay and dispersion correction procedure needed when a change in flow rate occurs during ABSS data acquisition. Additionally, this is the first study to measure the external delay and dispersion constants using a blood analog solution, a suitable alternative to blood when estimating external dispersion., (Creative Commons Attribution license.)

Objectives: Quantification of cytokine is indispensable to elucidate the mechanism of immune regulation at the molecular level, thereby contributing to the diagnosis and treatment of several diseases. Here, we aimed to determine the effect of detection method and storage conditions of specimens on the quantification of cytokine levels., Methods: We used four vacuum blood collection tubes containing EDTA, heparin, clot activator, gel and compared the changes in the expression levels of 14 cytokines in serum and plasma samples at different temperatures and durations of storage using AimPlex flow cytometry-based immunoassay. In addition, we analyzed the changes in cytokine sensitivity and its clinical relevance after re-establishing cutoff values compared to those set by the manufacturer., Results: The cytokine levels were higher in the plasma of healthy individuals than in their serum. Reliable values for most cytokines were obtained in gel-serum samples, centrifuged within 4 h of collection, and stored at -20 °C for up to 24 h. We measured cytokine levels in 1064 healthy controls using tubes containing separation gel to recalculate their cutoff values and observed changes in cytokine positivity in patients. IL-6 positivity increased from approximately 90% to 95% in patients with sepsis and severe pneumonia. Similarly, IL-8 increased from 48.7% and 41.7% to 79.5% and 63.9% in patients with sepsis and severe pneumonia., Conclusions: Cytokines are more stable in gel-serum than in plasma or clot activator-serum, and they should be quantified within 4 h or within 24 h if the sample is centrifuged and stored at -20 °C.

The presence of erythrocyte ghost cells (EG) in blood smears indicates intravascular haemolysis or in-vitro haemolysis. However, observer reliability in detection of EG has not been documented. Immediate blood smear preparation is advised but may not always be practical. This study investigated the reliability of EG detection and the impact of delayed blood smear preparation. Forty blood smears from dogs and cats were evaluated twice by four observers. EG development was studied in 59 dogs and nine cats, with smears prepared at 0, 2, and 24 h post-collection. Intra- and inter-observer reliability, as assessed using Krippendorff's Alpha, ranged from 0.567 and 0.949, and 0.522 and 0.848, respectively, indicating moderate to substantial agreement. No significant increase in EG occurrence was noted between 0 and 2 h, but a significant increase was observed at 24 h. The findings suggest that EG can be reliably detected and that blood smears for the evaluation of EG can be prepared up to 2 h after blood collection without compromising detection of EG., Competing Interests: Declaration of interest The authors have indicated that they have no affiliations or financial involvement with any organisation or entity with a financial interest in, or in financial competition with, the subject matter or materials discussed in this article., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: Home-based hospital services are becoming increasingly popular, and the addition of remote outpatient appointments after kidney transplantation facilitates more practical and closer follow-up. In this context, finger-prick self-sampling is an important aspect of monitoring of immunosuppressants and biomarkers. Nevertheless, several issues must be addressed to ensure the feasibility and quality when implementing microsampling in clinical practice. We summarize our experiences and opinions in this field., Methods: This article is based on the authors' experience regarding the laboratory and clinical implementation of finger-prick self-sampling in kidney transplant recipients. The referenced literature is related to the authors' knowledge in this field., Results: We present considerations for the selection of relevant analytes, key characteristics of selected volumetric sampling tools (Mitra and Capitainer), and the associated sampling pitfalls. In addition, we address the requirements for patients performing finger-prick sampling, appropriate design of methods and workflow, critical points for validation, and aspects related to logistics and digital solutions., Conclusions: Volumetric finger-prick self-sampling is suitable for monitoring immunosuppressants and certain biomarkers that are relevant to outpatient follow-up after kidney transplantation. We believe that a carefully designed system for the entire workflow, including patient training, will be beneficial in enabling a safe experience for transplant recipients, as well as ensuring overall efficiency and adequate quality. In the future, a combination of immunosuppressants with a wide range of biomarkers has significant potential for use in at-home self-sampling after kidney transplantation., Competing Interests: The authors declare no conflict of interest., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

β-hydroxybutyrate (BHB) is recommended as a measure of ketosis and is often assessed by capillary samples on point-of-care (POC) meters. However, liquid chromatography tandem mass spectrometry (LC-MS/MS) is considered the gold standard for assessing venous samples. The POC device KetoSure TM is recommended only for capillary samples from finger pricks. So far, KetoSure TM has not been compared to LC-MS/MS just as it has not been evaluated if the sampling site influences the BHB concentration. Blood samples were collected from 16 healthy, fasting individuals before and after ingestion of ketone monoester. BHB concentrations were measured in capillary samples from the earlobe and fingertip, and in venous blood using KetoSure TM . Venous plasma samples were collected for BHB quantification using LC-MS/MS. No sign of significant difference between values of BHB measured from the two capillary sampling sites were found. Interestingly, significantly higher values of BHB were measured in capillary samples compared to venous samples reflecting a systematic proportional relationship. No systematic difference was observed in the measured BHB concentrations when comparing KetoSure TM and LC-MS/MS results: However, a significant mean bias of 32% reflects a skewness at very low BHB concentrations. In conclusion, capillary BHB concentration did not exhibit variation between the earlobe and fingertip. Conversely, a significant bias was observed between venous and capillary blood and between the POC and LC-MS/MS methods. It is recommended that caution be exercised if individual monitoring of BHB changes encompasses both capillary and venous sampling.

Background: Early host immunity to acute respiratory infections (ARIs) is heterogenous, dynamic, and critical to an individual's infection outcome. Due to limitations in sampling frequency/timepoints, kinetics of early immune dynamics in natural human infections remain poorly understood. In this nationwide prospective cohort study, we leveraged a Tasso-SST based self-blood collection and stabilization tool (homeRNA) to profile detailed kinetics of the presymptomatic to convalescence host immunity to contemporaneous respiratory pathogens., Methods: We enrolled non-symptomatic adults with recent exposure to ARIs who subsequently tested negative (exposed-uninfected) or positive for respiratory pathogens. Participants self-collected blood and nasal swabs daily for seven consecutive days followed by weekly blood collection for up to seven additional weeks. Symptom burden was assessed during each collection. Nasal swabs were tested for SARS-CoV-2 and common respiratory pathogens. 92 longitudinal blood samples spanning the presymptomatic to convalescence phase of eight participants with SARS-CoV-2 infection and 40 interval-matched samples from four exposed-uninfected participants were subjected to high-frequency longitudinal profiling of 785 immune genes. Generalized additive mixed models (GAMM) were used to identify temporally dynamic genes from the longitudinal samples and linear mixed models (LMM) were used to identify baseline differences between exposed-infected (n = 8), exposed-uninfected (n = 4), and uninfected (n = 13) participant groups., Findings: Between June 2021 and April 2022, 68 participants across 26 U.S. states completed the study and self-collected a total of 691 and 466 longitudinal blood and nasal swab samples along with 688 symptom surveys. SARS-CoV-2 was detected in 17 out of 22 individuals with study-confirmed respiratory infection, of which five were still presymptomatic or pre-shedding, enabling us to profile detailed expression kinetics of the earliest blood transcriptional response to contemporaneous variants of concern. 51% of the genes assessed were found to be temporally dynamic during COVID-19 infection. During the pre-shedding phase, a robust but transient response consisting of genes involved in cell migration, stress response, and T cell activation were observed. This is followed by a rapid induction of many interferon-stimulated genes (ISGs), concurrent to onset of viral shedding and increase in nasal viral load and symptom burden. Finally, elevated baseline expression of antimicrobial peptides was observed in exposed-uninfected individuals., Interpretation: We demonstrated that unsupervised self-collection and stabilization of capillary blood can be applied to natural infection studies to characterize detailed early host immune kinetics at a temporal resolution comparable to that of human challenge studies. The remote (decentralized) study framework enables conduct of large-scale population-wide longitudinal mechanistic studies., Funding: This study was funded by R35GM128648 to ABT for in-lab developments of homeRNA and data analysis, a Packard Fellowship for Science and Engineering from the David and Lucile Packard Foundation to ABT for the study execution, sample collection, and analysis, and R01AI153087 to AW for data analysis., Competing Interests: Declaration of interests FYL, EB, and ABT filed patent 17/361,322 (Publication Number: US20210402406A1) through the University of Washington on homeRNA. ABT reports filing multiple patents through the University of Washington and receiving a gift to support research outside the submitted work from Ionis Pharmaceuticals. EB has ownership in Salus Discovery, LLC, and Tasso, Inc. that develops blood collection systems used in this manuscript, and is employed by Tasso, Inc. Technologies from Salus Discovery, LLC are not included in this publication. He is an inventor on multiple patents filed by Tasso, Inc., the University of Washington, and the University of Wisconsin. ABT and EB have ownership in Seabright, LLC, which will advance new tools for diagnostics and clinical research, potentially including the homeRNA platform. The terms of this arrangement have been reviewed and approved by the University of Washington in accordance with its policies governing outside work and financial conflicts of interest in research. AW reports receiving clinical trial support to their institution from Pfizer, Ansun Biopharma, Allovir, GlaxoSmithKline and Vir; receiving personal fees from Vir and GSK; all outside the submitted work. MB has clinical research support from Ansun Biopharma, GSK, Moderna, Vir Biotechnology, AstraZeneka, and Merck, and received personal fees from Allovir, Moderna, AstraZeneka, and Merck. JTS has clinical trial support from Aicuris and receives personal fees from Glaxo Smith Kline and Pfizer., (Copyright © 2024 The Author(s). Published by Elsevier B.V. All rights reserved.)

Background and Objectives: Di (2-ethylhexyl) phthalate (DEHP) plasticizer must be removed from polyvinylchloride (PVC) medical devices due to toxicity. DEHP/PVC blood bags were shown to provide stable quality under blood component production and to create good storage conditions for red blood cells concentrate (RBC). It is important that substitution of the DEHP maintains the RBC quality during storage, which should be achieved with Di (isononyl) cyclohexane-1,2-dicarboxylate (DINCH), although substitution of the plasticizer has been challenging., Materials and Methods: A DEHP-free Top & Bottom in-line RBC set was validated in a tertiary hospital blood bank facility. Volunteer blood donors were randomly allocated for blood collection into DINCH/PVC or DEHP/PVC set. The groups were additionally divided according to additive solution/filter combination: PAGGS-M + DINCH/PVC filter (only with DINCH/PVC set), and SAG-M + DINCH/PVC filter and SAG-M + DEHP/PVC filter (only with DEHP/PVC set). Processing and storage effects were assessed in all components., Results: RBC concentrates, platelet concentrates and plasma that was processed and stored in DEHP-free set fulfilled European requirements for quality. The cells stored in PAGGS-M after filtration through DEHP-free PVC filter showed the same low haemolysis compared with conventional set at 49 days of storage. Platelets stored in DINCH/PVC bag provided a sufficient quality of platelets after 7 days of storage. Plasma maintained the coagulation factors during 12 months of storage., Conclusion: A new DINCH/PVC set allows production of blood components of satisfactory quality in DEHP-free environment., (© 2024 The Author(s). Transfusion Medicine published by John Wiley & Sons Ltd on behalf of British Blood Transfusion Society.)

Objective: Primary aldosteronism (PA) is a common cause of secondary hypertension with unilateral and bilateral subtypes requiring different treatments. Adrenal vein sampling (AVS) is the gold standard for subtype differentiation but can be unsuccessful by challenging right adrenal vein anatomy. This study aimed to develop a clinical decision model using only measurements from the left adrenal vein (LAV) and peripheral blood (IVC) to differentiate between PA subtypes., Methods: The retrospective cohort study included 54 PA patients who underwent bilaterally successful AVS. The main objective was to determine optimal cut-off values for the LAV/IVC index, using ROC analysis for subtype prediction. The predictive value of this index was assessed with the Area Under the Curve (AUC). The Youden index calculated cut-off values, targeting a specificity >90% for PA subtype differentiation., Results: The cohort, averaging 48.5 ± 9.5 years in age, comprised 21 women and 33 men, among whom 26 presented with unilateral and 28 with bilateral disease. LAV/IVC values <1.2 indicated unilateral right-sided disease (specificity 91%, sensitivity 96%, AUC 0.98, 95% confidence interval (CI) 0.95-1.0), values 1.2-2.4 suggested bilateral disease (sensitivity 93%, specificity 64%, AUC 0.85, CI 0.73-0.96), whereas values ≥4.4 predicted unilateral left-sided disease (specificity 93%, sensitivity 60%, AUC 0.85, CI 0.73-0.96). Published literature aligns with our results on cut-off values., Conclusions: Utilizing the LAV/IVC index, over 70% of unsuccessful AVS procedures due to failed right adrenal cannulation could be interpreted with over 90% certainty regarding the PA subtype, preventing unnecessary resampling and aiding in determining the preferred treatment., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2025 ter Haar, van Goor, Corssmit, van Erkel, Ballieux, Dekkers and Nijhoff.)

Background: Microsampling of biological fluids followed by innovative sample pre-treatment reflects trends in bioanalytical chemistry. Volumetric absorptive microsampling (VAMS) enables exact whole blood volume collection and reduces the impact of hematocrit on the assay. In animal studies, it complies with the 3R principles (refine, reduce, replace). It allows for a gentle bleeding technique and a reduction in the number of laboratory animals by enabling ethically acceptable repeated blood collection from a single animal. Treating VAMS tips with electromembrane extraction (EME) in 96-well format offers a smart combination of non-invasive, low-volume blood collection with effective, environmentally friendly sample clean-up., Results: This study introduces the first application of EME in 96-well format for direct isolation of analytes from 10 μL of whole blood collected onto a VAMS device. Doxorubicin, a clinically used anticancer drug also utilized in cancer/cardio-oncology research involving rodents, where microsampling offers important advantages, and its metabolite doxorubicinol, were selected as relevant analytes. The optimized EME yielded reproducible recoveries for both analytes regardless of hematocrit levels, different anticoagulants, or free multivalent ions in the sample. Compared to conventional VAMS tips treatment, EME reduced matrix effects, increased throughput, and an environmental friendliness of the extraction. The EME followed by the UHPLC-MS/MS assay was validated for both analytes in whole blood absorbed onto VAMS tips. The same protocol was implemented to treat plasma to determine the blood-to-plasma ratio of the analytes in the same experiments. The practical utility was demonstrated by analyzing real samples collected from the doxorubicin-treated nude mice., Significance: The study offers a novel assay combining whole blood microsampling and sample clean-up in microextraction scale for preclinical pharmacokinetic studies with doxorubicin in rodents and for pharmacokinetic/pharmacodynamic modeling. This advancement in bioanalytical chemistry promotes scalable environmentally friendly procedures compatible with the 3R ethical principles in animal studies. Moreover, the concept of direct VAMS tips treatment with EME may also be easily translatable to clinical settings., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Objectives: to investigate the knowledge, attitudes, and practices of nurses regarding blood culture collection., Methods: a cross-sectional study was conducted in five Brazilian public hospitals with 112 nurses. Data were collected using an adapted questionnaire and analyzed through descriptive and inferential statistics., Results: nurses who did not consider themselves capable of collecting blood cultures had a 72% lower chance of performing the collection at the recommended site and an 83% lower chance of using the same needle for blood inoculation into the vials. Nurses working in the emergency department had a 75% lower chance of knowing the international benchmark for blood culture contamination rates, and those with less than 5 years in the position decreased their chance of accuracy in this matter by 79%., Conclusions: there are gaps in the knowledge, attitudes, and practices of nurses regarding blood culture collection. Standardization of the technique, periodic education, supervision and guidance of the collection team, and process auditing are recommended coping strategies.

Background: Except host and environmental factors influencing individual human cytokine responses, pre-analytical handling procedures and detection methods also affect cytokine levels., Methods: In this study, we used cytometric bead array (CBA) and chemiluminescence (ECL). These two methods were used to test serum and plasma samples from 50 healthy adult volunteers and 50 rheumatoid arthritis (RA) patients' cytokine levels. We evaluated the impact of storage temperature, collection times, and additives in collection tubes on the measurement of IL-6, IL-8, and TNF-α., Results: The finding of this study first indicated that the CBA assay for IL-6 and IL-8 showed excellent agreement with ECL for the same analysis, but the CBA assay and ECL for TNF-α measurement showed less agreement. Furthermore, we used two detection methods to find plasma cytokines showing more stability than serum cytokines, when the samples were stored at 4°C. Additionally, IL-8 concentration was affected by the storage conditions of whole blood from the time of collection until further processing at room temperature. We also found heparin tubes showed higher levels of IL-6 and TNF-α than other tubes at room temperature., Conclusions: In general, the best values for IL-6, IL-8, and TNF-α were found in EDTA samples, stored at 4°C, and centrifuged quickly within 2 hours. The effect of pre-analytical handling procedures and detection methods on cytokine levels we identified would provide a basis for clinical cytokine detection.

Objectives: Adrenal vein sampling (AVS) is an established procedure for assessing subtype patients with primary aldosteronism (PA). However, it is technically challenging, with high failure rates, which limits its application in clinical practice. Our study aimed to evaluate the safety and efficacy of a single-catheter modified approach for AVS., Methods: The clinical, angiographic, and procedural data of 182 consecutive patients who underwent AVS procedures between May 2020 and May 2023 were collected and analyzed. The single-catheter modified approach was performed as a single 5 F Tiger catheter with only one-time manual reshaping, which was recommended for sequential bilateral adrenal cannulations., Results: Of the 182 consecutive patients, 174 (95.6%) had successful bilateral adrenal cannulation. The single-catheter modified approach was successfully performed to cannulate the right adrenal vein in 176 (96.7%) patients, while another six (3.3%) patients needed at least a second manual reshaping for 5 F Tiger catheters. For left adrenal cannulation, a single-catheter modified approach was successfully used in 179 (98.4%) patients, whereas 5 F Tiger catheters with at least second-time manual reshaping were used in the remaining three (1.6%) patients. The procedural period was 15.6 ± 10.8 min, the fluoroscopy time was 4.2 ± 1.5 min, and the diagnostic contrast was 15.5 ± 4.8 mL. The incidence of procedure-related complications associated with AVS was 1.1%. The cumulative summation assessment illustrated that the learning curve for the operating procedure required up to 29 cases, indicating that the procedure time was shortened after 29 cases., Conclusions: The single-catheter modified approach is an effective, safe, and feasible technique for AVS treatment. In particular, this improved method is not difficult for beginners with high technical success rates., Competing Interests: Declaration of conflicting interestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Enhanced fibrinolysis or hyperfibrinolysis may lead to life-threatening blood loss, while reduced activity may contribute to thrombosis. Euglobulin clot lysis time (ECLT) is a manual method that measures plasma fibrinolytic activity and is considered the gold standard. However, the data on reference interval is scarce and outdated. We have employed one-sided reference interval (>3 h) since the implementation of ECLT in our laboratory; therefore, we aimed to establish reliable ECLT reference interval and to explore the possible preanalytical influence of different blood collection tubes on the established ECLT reference interval. Establishing a reference interval for fibrinolysis was performed according to CLSI EP28-A3c guidelines by employing a posteriori direct sampling technique. The predefined exclusion criteria included a history of malignant or hepatobiliary disease, a history of deep vein thrombosis/pulmonary embolism (DVT/PE), an acute inflammatory state at the time of the venipuncture. We collected vein blood samples in Vacutest plastic coagulation tubes (Kima, Italy) and Vacutainer glass coagulation tubes (Beckton Dickinson, USA) containing 0.109 mol/l buffered trisodium citrate as an anticoagulant at a blood-to-anticoagulant ratio 9 : 1. We calculated two-sided reference interval and presented as 2.5th and 97.5th percentiles. ECLT values did not differ between sexes or the types of tubes enrolled in the study ( P  = 0.8979). The established reference interval ranged from 130 to 297 min for the KIMA Vacutest tube and from 120 to 292 min for the BD Vacutainer tube. The established ECLT reference interval differed significantly from the currently used cut-off value in our laboratory, thus enabling the assessment of hyperfibrinolysis by employing double-sided reference interval., (Copyright © 2024 Wolters Kluwer Health, Inc. All rights reserved.)

Pharmacokinetic (PK) studies pose unique technical challenges. We present the design of a Phase 1, open-label, fixed-sequence, PK trial that aimed to compare the timing accuracy of participant- versus staff-collected data, and we provide safety and tolerability outcomes for centanafadine treatment. Healthy adults aged 18-55 years received a single 100-mg centanafadine sustained-release tablet at Visits 1, 2, and 4. PK samples (venous sampling and blood microsampling) and safety assessments (12-lead electrocardiograms [ECGs] and vital signs) were collected by clinical site staff only at Visit 1. At Visit 2, site staff collected venous blood, and participants obtained blood microsamples, a 6-lead ECG, and vital signs under staff supervision. At Visit 4, participants obtained blood microsamples, a 6-lead ECG, and vital signs remotely. The absolute differences between actual and scheduled collection times for PK samples, ECGs, and vital signs are reported descriptively. Of the 20 participants, at least 75% obtained blood microsamples within 10 minutes of the planned nominal time. Absolute differences between actual and scheduled collection times of ECGs and vital signs were small. No adverse events were related to treatment. Overall, results support the feasibility of at-home collection of PK samples, ECGs, and vital signs., (© 2024 The Author(s). Clinical Pharmacology in Drug Development published by Wiley Periodicals LLC on behalf of American College of Clinical Pharmacology.)

In this study, we examined the effect of a bundled approach to blood collection for blood culture on decreasing contamination. Commensal organisms were considered contaminants on the basis of the clinical course if they were recovered from only a single blood draw (set) and if a positive result for two sets was not obtained within 72 hours. The main elements of the bundle were blood collection by venipuncture, skin preparation with a chlorhexidine alcohol swab, disinfection of culture bottles, and use of a sterile blood transfer device instead of the two-needle technique for inoculation. In the bundle intervention, chlorhexidine alcohol was first introduced in the hospital, and use of the blood transfer device was increased during the intervention. Both items were used in most patients requiring blood cultures. Blood collection through a line caused contamination in only one case. The contamination rate decreased significantly from 2.0% to 1.0% after introduction of the bundle approach (3-year control period vs. 2-year bundle period, p<0.001), and a significant decrease in the contamination rate was observed for coagulase-negative Staphylococcus (p<0.001). A high contamination rate was found in August and September during the control period. The contamination rate of Bacillus species was significantly higher in those 2 months than in other months. A seasonal increase was not observed during the bundle period. A low contamination rate of 1.0% was achieved using our bundled collection approach for blood culture., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Doi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Low volume sampling technologies have gained popularity as they are minimally invasive, reduce patient burden, enhance population diversity, and have the potential to facilitate decentralized clinical trials. Herein, we validated a Gyrolab assay to measure soluble Mucosal Addressin Cell Adhesion Molecule 1 (sMAdCAM-1) in dried blood samples collected using two low volume sampling devices, Mitra and Tasso-M20. This validated assay was implemented in a proof-of-concept study to compare three low volume sampling devices (Mitra, Tasso-M20 and TassoOne Plus) with serum collected via venipuncture from healthy volunteers receiving etrolizumab. We observed significantly higher concentration of sMAdCAM-1 in dried blood samples collected using Mitra and Tasso-M20 compared to serum in some paired samples, which was attributed to interference from the dried blood extraction buffer. To mitigate this interference, samples required substantial dilution into the appropriate buffer, which negatively impacted the detectability of sMAdCAM-1 with the Gyrolab assay. By employing the Quanterix single molecule array (Simoa), known for its superior assay sensitivity, the interference was minimized in the diluted samples. Both liquid blood collected in TassoOne Plus and dried blood collected using Mitra and Tasso-M20 demonstrated great concordance with serum for sMAdCAM-1 measurement. However, a bias was observed in Mitra dried blood samples, presumably due to the different sample collection sites in comparison with venipuncture and Tasso devices. Our study highlights the potential of low volume sampling technologies for biomarker analysis, and underscores the importance of understanding the challenges and limitations of these technologies before integrating them into clinical studies., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Accurate measurement of plasma protein binding (PPB) is of critical importance in drug discovery. Methodologies for PPB measurement continue to evolve to address the challenges of highly bound compounds. In order to generate high quality PPB data, it is crucial to not only apply state-of-the-art methods and highly sensitive and selective detectors, but also use high-quality plasma. In this study, we found that plasticizers, leaching from polyvinyl chloride (PVC) plasma storage bags, interfered with drug binding to both human α1-acid glycoprotein (AAG) and human serum albumin (HSA). Several AAG and HSA binding drugs were used to probe the differences in PPB using blood/plasma collected and stored in PVC bags or glass tubes through vacutainers. The results showed that plasma collected using vacutainers into the glass tubes has lower plasma fraction unbound (f u,p ) values than those from the PVC bags. The f u,p differences can be as high as 32-fold. Hence, it is recommended to use vacutainers and glass tubes rather than PVC bags, for blood collection and plasma storage. Plasma from animal species collected using polypropylene syringes into polyethylene tubes showed no differences in f u,p from plasma collected using vacutainers into glass tubes. Not all compounds are sensitive to plasticizer interference for PPB. It is therefore important to select appropriate positive controls for f u,p  measurement, such as warfarin for HSA and imatinib for AAG, to monitor the quality of plasma and minimize the interference from plasticizers., Competing Interests: Declarations. Conflict of Interest: Authors are employees of Pfizer Inc., New York, NY, USA, and may hold Pfizer stocks., (© 2024. The Author(s), under exclusive licence to American Association of Pharmaceutical Scientists.)

Objectives: In most countries the majority of patients are in outpatient care. In difference to hospitalized patients, their blood samples often take hours after collection to centrifugation. The study investigates the release of potassium and the development of pseudohyperkalemia in lithium heparin (Li-Hep) and serum blood collection tubes over time., Methods: From 201 donors 4 serum and 4 Li-Hep blood collection tubes were taken each. After 0.5, 4, 6 and 8h whole blood was centrifuged, and potassium levels were determined. To simulate the preanalytic conditions, the samples with a storage time >0.5h were shaken on a standard shaker for 1h and stored at 4-8°C for the remaining time., Results: Over time, significant more potassium was released before centrifugation from the Li-Hep plasma than from serum (1.21 vs 0.94 mmol/L). After 6h, the two groups were no longer highly statistically significantly different (potassium mean: 5.01 mmol/L in serum group, 4.92 mmol/L in Li-Hep group). In the Li-Hep group 164 donors developed a pseudohyperkalemia after 8h, compared to 76 in the serum group., Significance: The decision as to which material is best suited should not only be based on which value comes closest to the physiological situation immediately after blood collection. The subsequent preanalytic circumstances must also be considered. Serum tubes appear to be at least as suitable for potassium determination as Li-Hep tubes. In terms of patient blood management, serum provides the possibility of performing a wider range of analyses in the outpatient setting., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Reuter et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Micro-computed tomography (micro-CT) is a real-time, intuitive, sensitive, and minimally invasive technique for monitoring changes from pulmonary nodules (PN) to lung cancer (LC). The integration of submandibular vein blood sampling enables rapid, stable, and straightforward detection of imaging and key target alterations during the progression of PN to LC. In this study, we administered a dosage of 100 mg/kg of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone in A/J mice to develop a lung adenocarcinoma model. Disease progression in the experimental animals was then monitored through submandibular vein blood sampling and micro-CT assay. Experimental results showed the presence of nodular foci in the lungs of some animals by the 10 th week, with the development of lung adenocarcinoma images becoming evident by the 21 st week. In conclusion, micro-CT can effectively observe pathological changes in the lungs of mice and, when combined with submandibular vein blood sampling, can dynamically monitor changes in blood, protein, and targets. This method provides a highly specific, simple, and sensitive approach for drug screening, pharmacokinetic testing, toxicological experiments, and safety studies.

Objectives: There is a lack of analyte stability data in whole blood (WB). The aim of this study was to determine the allowable delay in WB processing for lactate dehydrogenase (LDH), folate, vitamin B12, iron and phosphate measurement. The stability of LDH, folate and vitamin B12 was also assessed in stored serum at clinically relevant time points., Methods: Blood was taken from n=10 volunteers into Sarstedt serum gel tubes. We assessed stability in WB at room temperature up to 24 h, and stability in refrigerated serum up to 72 h. Mean percentage deviation at each time point was compared to criteria for minimum allowable bias., Results: Results produced from one individual were removed due to discordant results, leaving n=9 specimens at each time point. Stability of folate and phosphate was variable in WB across 24 h, but was deemed to be clinically acceptable. LDH was unstable in WB, iron was stable for at least 12 h, and vitamin B12 and ferritin were acceptable for up to 24 h. Serum LDH, folate and vitamin B12 all demonstrated acceptable stability in refrigerated serum stored for up to 72 h., Conclusions: Blood should ideally be centrifuged within 7 h for phosphate, LDH and folate, and 12 h for iron. However, for phosphate, folate and iron, there is likely to be little clinical impact if serum separation is delayed up to 24 h. Further research is needed to assess LDH stability in WB at 0-12 h, but changes are minimal at 12 h. All other analytes assessed showed acceptable stability across the time-points tested., (© 2024 Walter de Gruyter GmbH, Berlin/Boston.)

Background: The benefits of pharmacotherapy with sirolimus (SIR) in pediatric transplant recipients are well established. Traditionally, whole blood samples have been used to measure SIR concentrations. Volumetric Absorptive Microsampling (VAMS) is an alternative sampling strategy suitable for Therapeutic Drug Monitoring (TDM). In this study, we developed and validated two liquid chromatography-tandem mass spectrometry (LC-MS/MS) methods for determining SIR concentrations in whole blood (WB) and capillary whole blood samples collected using a VAMS-Mitra™ device., Methods: We used protein precipitation during WB sample preparation and dispersive liquid-liquid microextraction (DLLME) with methyl tert-butyl ether for VAMS sample preparation to optimise the analyte extraction process. The described validation protocols were cross-validated, confirming the equivalence of the whole-blood and VAMS-based methods. Furthermore, the developed methods were evaluated in two three-level rounds of an external proficiency-testing scheme., Results: The analytical methods were successfully validated within the calibration range of SIR (0.5-60 ng/ml). The validation parameters met the European Medicines Agency (EMA) and the International Association of Therapeutic Drug Monitoring and Clinical Toxicology (IATDM&CT) acceptance criteria. No hematocrit (tested in the range of 24.3-64.1%), matrix, or carry-over effects were observed. Cross-validation confirmed the interchangeability between VAMS-LC-MS/MS and WB-LC-MS/MS methods. The developed methods were successfully implemented for SIR determination in 140 clinical samples (70 each of WB and VAMS) from pediatric renal transplant recipients, demonstrating their practicality and reliability., Conclusion: The VAMS-based method has been rigorously tested and is clinically equivalent to the reference WB-LC-MS/MS method. Additionally, clinical validation confirmed the utility of the presented methods for TDM of the SIR in the pediatric population after renal transplantation., Competing Interests: Declarations. Ethical approval: This study was conducted in accordance with the Declaration of Helsinki and the International Council for Harmonization Guidance for Good Clinical Practice. The Bioethics Committee of the Children’s Memorial Health Institute in Warsaw approved this project (number of agreements: 15/KBE/2023, with later amendments). Competing interests: The authors declare no competing interests., (© 2024. The Author(s).)

Blood plasma storage is a crucial element of pediatric biobanking. Improperly stored or handled specimens (e.g., at > -30°C) can result in altered biomolecular compositions that no longer reflects in vivo reality. We report application of a previously developed assay in adults-the ΔS-Cys-Albumin assay, which facilitates estimation of plasma and serum exposure to thawed conditions-to a population of pediatric EDTA plasma samples from patients aged 3-18 years to determine the assay's applicability, estimate its reference range for pediatric samples, and assess the impact of pre-centrifugation delay at 0°C. In addition, the effect of plasma thawed-state exposure to a range of times at 23°C, 4°C, and -20°C on ΔS-Cys-Albumin was evaluated. Using 98 precollected and processed pediatric EDTA plasma specimens, no difference was found in ΔS-Cys-Albumin under conditions of pre-centrifugation delay for up to 10 hours at 0°C. This lack of change allowed us to estimate a pediatric reference range for ΔS-Cys-Albumin of 7.0%-22.5% (mean of 12.8%) with a modest Pearson correlation between ΔS-Cys-Albumin and age ( p = 0.0037, R 2 = 0.29). ΔS-Cys-Albumin stability in six specimens at 23°C, 4°C, and -20°C was also evaluated. Plateaus in the decay curves were reached by 1 day, 7 days, and 14-28 days at these respective temperatures. The estimated pediatric reference range observed in children was lower than that previously observed in 180 adults of 12.3%-30.6% (mean of 20.0%), and the slope of the age correlation in children was twice as steep as that from adults. ΔS-Cys-Albumin decay curves at 23°C, 4°C, and -20°C were similar to those previously observed in adults. The data reported here support the use of ΔS-Cys-Albumin in evaluating the integrity and overall exposure of pediatric EDTA plasma specimens to thawed conditions. In doing so, they add an important quality control tool to the biobanker's arsenal.

Objectives: To evaluate blood culture sample volumes, identify factors linked to insufficient samples, and compare volumes among neonates treated for culture-negative-sepsis, sepsis-rule-outs, and bloodstream infections (BSI)., Methods: Observational cohort of blood cultures collected during NICU stay. Association of age, weight, gender, source, and collection time with lower-than-recommended volumes was determined by logistic regression. Blood culture inocula of patients with culture-negative-sepsis, sepsis rule-out, and BSI were compared using ANOVA., Results: 742 blood cultures were obtained from 292 neonates. Median inoculum was 1 mL (IQR:0.6-1.4), and 259 bottles (35%) had inocula <0.9 mL. Night shift sample collection was associated with lower-than-recommended volumes (p = 0.006). No difference in sample volumes was observed between culture-negative-sepsis, sepsis-rule-outs, and BSI (p = 0.5)., Conclusions: Median NICU blood culture volumes align with recommendations. Night shift collections correlate with lower volumes. Sample volumes don't differ in patients with culture-negative-sepsis, BSI, and sepsis-rule-out, and should not be a justification for longer duration of antibiotics., Competing Interests: Ethics approval and consent to participate: All methods were performed in accordance with the relevant guidelines and regulations. Approval was obtained from the Children’s National Institutional Review Board (Pro00011458). Informed consent was waived. Competing interests: Dr. Soghier is an editor for American Academy of Pediatric “Reference Range Values in Pediatric Care” and “Neonatal Simulation” textbooks. The remaining authors of this manuscript have no conflicts of interest to disclose., (© 2024. The Author(s), under exclusive licence to Springer Nature America, Inc.)

Background: Nonpharmacological methods such as white noise and therapeutic touch can be used in pain management in neonates., Purpose: This randomized controlled study evaluated the effects of white noise and therapeutic touch during heel lance procedures on pain, comfort levels, and physiological parameters in healthy neonates., Methods: This parallel, randomized controlled study was conducted in the Obstetrics and Gynecology Service of a regional hospital. The sample comprised 160 neonates with gestational ages of >35 weeks randomly assigned to 4 groups (white noise [WN], therapeutic touch [TT], white noise + therapeutic touch [WT], and control [CG] group). Pain and comfort levels were evaluated according to the Neonatal Infant Pain Scale, and the COMFORTneo Scale. The primary outcomes were pain and comfort levels, and the secondary outcomes were heart rate and SpO2 levels. The Kruskal-Wallis test was used to compare the scale scores among groups., Results: There were significant differences among groups in terms of Neonatal Infant Pain Scale and COMFORTneo scores (P < .05). The pain scores for the white noise, therapeutic touch, and white noise + therapeutic touch groups were 4.2 ± 2.0, 5.2 ± 1.6, and 3.3 ± 1.7, respectively. There was a significant difference in average heart rate during the heel lance procedure among the groups (P < .05). Pain scores of the intervention groups were lower compared to the control group., Implications for Practice and Research: The combination of white noise and therapeutic touch was more effective in reducing pain and increasing comfort levels. Nurses could reduce procedural pain by applying these pain relief methods., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2024 by The National Association of Neonatal Nurses.)

Background: Exposing blood specimens to air reduces plasma total carbon dioxide (TCO 2 ). We evaluated the degree of TCO 2 reduction attributed to open collection of neonatal blood in BD microtainers® (microtainers), microtainer transport duration and delayed testing of open plasma aliquots., Methods: Venous blood was aliquoted into open microtainers in a 3x4 factorial design to simulate combined effects of blood volume (0.2-0.6 mL) and air exposure duration (0-5 min), with blood drawn in vacutainers as a control. Separate effects of in-hospital transport duration (0-120 min; whole blood), off-site transport duration (0-24 h; centrifuged whole blood), and the duration plasma aliquots remained open (0-120 min) were evaluated by repeated testing. Findings were analyzed using repeated-measures ANOVA and Student's T-tests., Results: In the factorial experiment, mean plasma TCO 2 in microtainers was on average 3.5 mmol/L lower than in vacutainers. Smaller blood volume but not greater air exposure duration significantly (p < 0.05) reduced TCO 2 . Mean TCO 2 in filled (0.6 mL; 1-5 min air exposure) microtainers was on average 2.9 mmol/L lower than in vacutainers. Simulated off-site transport of microtainers containing centrifuged whole blood significantly reduced TCO 2 (4 h; mean change = -1.5 mmol/L), as did delayed testing of aliquoted plasma (15 min; mean change = -1.3 mmol/L)., Conclusions: Plasma TCO 2 decreased with reduced microtainer blood volume, extended off-site transport duration of centrifuged whole blood and testing delay of aliquoted plasma. To minimize TCO 2 reduction, microtainers should be fully filled and tested rapidly. Laboratories should also consider whether an interpretive comment, correction factor or separate reference intervals are appropriate for these tests., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Venous blood collection is a widely used medical diagnostic technique, and with rapid advancements in robotics, robotic venous blood collection has the potential to replace traditional manual methods. The success of this robotic approach is heavily dependent on the quality of vein imaging. In this paper, we develop a vein imaging device based on the simulation analysis of vein imaging parameters and propose a U-Net+ResNet18 neural network for vein image segmentation. The U-Net+ResNet18 neural network integrates the residual blocks from ResNet18 into the encoder of the U-Net to form a new neural network. ResNet18 is pre-trained using the Bootstrap Your Own Latent (BYOL) framework, and its encoder parameters are transferred to the U-Net+ResNet18 neural network, enhancing the segmentation performance of vein images with limited labelled data. Furthermore, we optimize the AD-Census stereo matching algorithm by developing a variable-weight version, which improves its adaptability to image variations across different regions. Results show that, compared to U-Net, the BYOL+U-Net+ResNet18 method achieves an 8.31% reduction in Binary Cross-Entropy (BCE), a 5.50% reduction in Hausdorff Distance (HD), a 15.95% increase in Intersection over Union (IoU), and a 9.20% increase in the Dice coefficient (Dice), indicating improved image segmentation quality. The average error of the optimized AD-Census stereo matching algorithm is reduced by 25.69%, and the improvement of the image stereo matching performance is more obvious. Future research will explore the application of the vein imaging system in robotic venous blood collection to facilitate real-time puncture guidance.

Objectives: This is a protocol for a Cochrane Review (intervention). The objectives are as follows: To assess the benefits and harms of different strategies to minimize blood sampling in preterm infants., (Copyright © 2024 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.)

Objectives: This study examined the comparability of venous and capillary blood samples with regard to routine chemistry analytes., Methods: Venous and capillary blood samples were collected from adult patients to assess comparability of alanine transaminase, albumin, alkaline phosphatase, apolipoprotein B, aspartate aminotransferase, total bilirubin, calcium, chloride, creatin kinase, creatinine, C-reactive protein, ferritin, folic acid, free T4, gamma glutamyltransferase, glucose, high density lipoprotein cholesterol, iron, lipase, lipoprotein a, magnesium, phosphate, postassium, prostate specific antigen, sodium, total cholesterol, total protein, transferrin, triglycerides, thyroid stimulating hormone, urate, urea, vitamin B12 and 25-hydroxyvitamin-D3. Furthermore, hemolysis-icterus-lipemia Index (HIL-Index) was measured for all samples. All measurements were performed using the Siemens Atellica ® CH or IH Analyzer. Deming regression analysis and mean relative differences between venous and capillary measurements of each analyte were contrasted with the desirable total allowable error (TEa) and Clinical Laboratory Improvement Amendments (CLIA) 2024 proposed acceptance limits for proficiency testing., Results: Deming regression and mean relative differences demonstrated excellent comparability between venous and capillary samples for most measured analytes., Conclusions: Capillary and venous samples showed comparable results for almost all studied chemistry analytes. Of the 33 studied analytes for which TEa criteria where available, 30 met TEa criteria. CLIA 2024 criteria where available for 29 of the studied analytes of which only glucose did not meet the criteria. In conclusion, capillary blood draw is a suitable alternative for venous blood sampling for measuring most of the investigated analytes. This benefits patients with fear of needles and might pave the way for remote self-sampling., (© 2024 the author(s), published by De Gruyter, Berlin/Boston.)

Background: Tertiary hospitals in China are confronted with significant challenges due to limited spatial capacity and workforce constraints, leading to saturated allocation of medical resources and restricted growth in medical service provision. The incorporation of digital health into medical service process reengineering (MSPR) marks a pivotal transformation and restructuring of conventional health service delivery models. Specifically, the application of MSPR to blood sampling services processes reengineering (BSSPR) holds promise for substantially enhancing the efficiency and quality of medical services through streamlining and optimizing these procedures. However, the comprehensive impact of BSSPR has been infrequently quantified in existing research., Objective: This study aims to investigate the influence of BSSPR on the efficiency and quality of medical services and to elucidate the key informative technological support points underpinning BSSPR., Methods: Data were collected from both the new and old laboratory information systems from August 1, 2019, to December 31, 2021. A combination of statistical description, chi-square test, and t test was used to compare check-in time and waiting time of outpatients before and after the implementation of BSSPR. An interrupted time-series design was used to analyze the impact of BSSPR on medical service efficiency and quality, enabling the control of confounding variables, including changes in medical human resources and both long- and short-term temporal trends., Results: BSSPR had an impact on the efficiency and quality of medical services. Notably, there was a significant increase in the number of patients receiving blood sampling services, with a daily service volume increase of ~150 individuals (P=.04). The average waiting time for patients decreased substantially from 29 (SD 36) to 11 (SD 11) minutes, indicating a marked improvement in patient experience. During the peak period, the number of patients receiving blood sampling services per working hour statistically increased from 9.56 to 16.77 (P<.001). The interrupted time-series model results demonstrated a reduction in patients' waiting time by an average of 26.1 (SD 3.8; 95% CI -33.64 to -18.57) minutes. Although there was an initial decline in the number of outpatients admitted following BSSPR implementation, an upward trend was observed over time (β=1.13, 95% CI 0.91-1.36)., Conclusions: BSSPR implementation for outpatients not only reduced waiting time and improved patients' experience but also augmented the hospital's capacity to provide medical services. This study's findings offer valuable insights into the potential advantages of BSSPR and underscore the significance of harnessing digital technologies to optimize medical service processes. This research serves as a foundational basis and provides scientific support for the promotion and application of BSSPR in other health care contexts. By continuing to explore and refine the integration of digital technologies in health care, we can further enhance patient outcomes and elevate the overall quality of medical services., (©Wenmin Liao, Rong He, Zhonglian He, Nan Shi, Dan Li, Aihua Zhuang, Feng Gan, Ying Sun, Chaofeng Li. Originally published in the Journal of Medical Internet Research (https://www.jmir.org), 12.11.2024.)

Background: Researching medical sample storage is crucial for maintaining the integrity of biological specimens and ensuring the accuracy of research investigations and diagnostic tests. Improper storage conditions can lead to sample degradation, compromising the reliability of results. Standardized storage procedures are essential for quality control, particularly in multicenter trials where samples are collected and processed at various locations. Moreover, ethical considerations dictate careful handling of patient samples to uphold privacy and rights., Methods: This study focuses on the surface phenotype of T cells, which is vital for diagnosing immunodeficiency disorders and autoimmune diseases and for monitoring disease activity and treatment efficacy. The effect of storage duration on T cell surface proteins is multifactorial, influenced by factors like protein degradation, cellular metabolism, and cytokine release. Long-term storage can lead to the gradual loss of T cell function, necessitating techniques to preserve cell activity. Changes in surface markers can affect disease diagnosis, emphasizing the importance of accurate sample processing., Results: Findings from this study reveal time-dependent changes in T cell surface markers during storage. CD3 levels declined significantly after the fourth day, with FITC labeling proving superior to APC. CD4 levels remained consistent until the fourth day, contrasting with previous findings on foreskin tissue. HLA-DR levels declined rapidly, indicating unsuitability for storage, consistent with other studies on cryopreserved cells. CD16 and CD8 levels decreased gradually, while CD56 declined rapidly after the third day, consistent with recent research., Conclusions: There were detectable and significant differences after the samples were stored for an improper period, which may have affected the integrity of the results, suggesting that understanding the factors influencing T cell surface protein changes during storage is crucial for maintaining result integrity.

Purpose: This study aimed to examine the effect of mechanical vibration and the ShotBlocker® device on pain level, crying time, and procedure time during a heel lance in healthy term neonates., Design and Methods: A total of 105 healthy-term neonates were randomized into three groups: control (n = 36), mechanical vibration (n = 33), and ShotBlocker® (n = 36). The control group underwent a routine heel lance procedure. The neonates in the mechanical vibration group received mechanical vibration to the extremity for 30 s before the heel was lanced. For the ShotBlocker® group, a ShotBlocker® was placed on the area where the heel lance procedure would occur and the heel was lanced. The heel lance procedure was videotaped, and the neonates' pain scores at 1 min before, 2 min after, and 5 min after the procedure, crying time, and procedure duration were recorded and were evaluated by two independent raters. Data were evaluated using the chi-square test and analysis of variance. The analysis of variance, Bonferroni, Dunnett T3 analysis, and effect size were used in the analyses of repeated measures. The study was approved by an ethics committee. Informed consent was obtained from parents., Results: The pain level of the neonates in the mechanical vibration group was lower than those of the control and ShotBlocker® group during and at 2 min and 5 min after the procedure (F = 12.063, p = 0.000; F = 4.580, p = 0.012; and F = 6.145, p = 0.003, respectively). The duration of neonate crying time in the mechanical vibration group was lower than in the control and ShotBlocker® groups (F = 4.598, p = 0.012). The heel lance duration was similar in the groups (F = 1.369, p = 0.259)., Conclusion: Mechanical vibration is an effective method to reduce the pain level and crying time associated with heel lance procedures in neonates., Practice Implications: This study provides evidence to nurses that the ShotBlocker is not an effective method for reducing pain associated with the heel lance procedure but that mechanical vibration is an effective method., Clinical Trials Registration: The study was registered at Clinical-Trials.gov (NCT06380556)., Competing Interests: Declaration of competing interest No conflict of interest has been declared by the authors., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Purpose: The primary objective of this study is to evaluate the effectiveness of finger puppets, abeslang puzzles, and pinwheels in reducing pain and anxiety in children aged 4-6 years during blood sampling procedures in a pediatric emergency department., Design and Methods: This study was a four-arm parallel group randomised controlled trial design conducted in the pediatric emergency department of a children's hospital in Western Türkiye between June 2023 and June 2024. Children (n = 160) were randomly assigned into four groups in a 1:1:1:1 ratio. The intervention groups consisted of children aged 4-6 years as finger puppet (n = 40), abeslang puzzle (n = 40), pinwheel (n = 40) and control group (n = 40). Data were collected using Personnel Information Form, Wong-Baker FACES Pain Rating Scale, and the Children's Anxiety Meter-State. The participants themselves, their parents, the nurse and the researcher rated the pain and anxiety levels associated with the blood sampling procedure. These trials are registered with ClinicalTrials.gov (NCT05904483)., Results: ANOVA was used to compare the mean Wong-Baker FACES Pain Rating Scale scores among the groups. According to all raters (child, parent, nurse, and researcher), the finger puppet group had the lowest mean score, followed by the pinwheel, abeslang puzzle, and control groups (p < 0.05). According to the nurse and researcher evaluations after the procedure, the finger puppet group had the lowest mean score on The Children's Anxiety Meter-State, followed by the abeslang, pinwheel and control groups (p < 0.05)., Conclusion: Finger puppet, pinwheel and abeslang puzzle methods were effective in reducing pain and anxiety during blood sampling procedure in children., Practice Implications: Pediatric nurses can safely use finger puppet, pinwheel and abeslang puzzle methods to reduce pain and anxiety during blood sampling procedure in preschool children., Competing Interests: Declaration of competing interest The author(s)declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Sexually minoritized men (SMM) with HIV who use stimulants experience difficulties achieving and maintaining an undetectable viral load (VL). Home-based VL monitoring could augment HIV care by supporting interim, early identification of detectable VL. We describe implementation challenges associated with a home-collection device for laboratory-based VL testing among SMM with HIV who use stimulants. From March-May 2022, cisgender SMM with HIV reporting moderate-to-severe stimulant use disorder and suboptimal (< 90%) past-month antiretroviral therapy (ART) adherence were recruited via a consent-to-contact participant registry. Eligible men completed teleconference-based informed consent and were mailed a HemaSpot-HD blood collection device (volume capacity 160 µL; lower limit of detection 839 copies/mL) with detailed instructions for home blood self-collection and return shipment. Implementation process measures included estimated blood volume and VL quantification. Among 24 participants, 21 (88%) returned specimens with a median duration of 23 days (range: 10-71 days) between sending devices to participants and receiving specimens. Of these, 13/21 (62%) included enough blood (≥ 40 µL) for confidence in detectable/undetectable results; 10/13 (77%) had detectable VL, with 4/10 (40%) were quantifiable at ≥ 839 copies/mL. The remaining 8/21 had low blood volume (< 40 µL), but 3/8 (38%) still had detectable VL, with 1/3 (33%) quantifiable at ≥ 839 copies/mL. Home blood collection of ≥ 40 µL using HemaSpot-HD was feasible among this high-priority population, with > 50% having a VL detected. However, interim VL monitoring using HemaSpot-HD among those experiencing difficulties with ART adherence may be strengthened by building rapport via teleconferencing and providing detailed instructions to achieve adequate sample volume., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Aims: Dried blood volumetric absorptive microsamples (VAMS) may facilitate home-based sampling to enhance therapeutic drug monitoring after transplantation. This study aimed to clinically validate a liquid chromatography-tandem mass spectrometry assay using 2 VAMS devices with different sampling locations (Tasso-M20 for the upper arm and Mitra for the finger). Patient preferences were also evaluated., Methods: Clinical validation was performed for tacrolimus and mycophenolic acid by comparison of paired VAMS and venipuncture samples using Passing-Bablok regression and Bland-Altman analysis. Conversion of mycophenolic acid VAMS to serum concentrations was evaluated using haematocrit-dependent formulas and fixed correction factors defined a priori. Patients' perspectives, including useability, acceptability and feasibility, were also investigated using established questionnaires., Results: Paired samples (n = 50) were collected from 25 kidney transplant recipients. Differences for tacrolimus whole-blood concentration were within ±20% for 86 and 88% of samples from the upper arm and fingerstick, respectively. Using correction factors of 1.3 for the upper-arm and 1.47 for finger-prick samples, 84 and 76% of the paired samples, respectively, were within ±20% for mycophenolic acid serum concentration. Patient experience surveys demonstrated limited pain and acceptable useability of the upper-arm device., Conclusions: Tacrolimus and mycophenolic acid can be measured using 2 common VAMS devices with similar analytical performance. Patients are supportive of home-based monitoring with a preference for the Tasso-M20 device., (© 2024 The Author(s). British Journal of Clinical Pharmacology published by John Wiley & Sons Ltd on behalf of British Pharmacological Society.)

Objectives: It is recommended to adjust the dose of vancomycin (VCM) with a target area under the concentration-time curve (AUC) of 400-600 μg·h/mL. Factors that affect the deviation between AUCs are estimated from the trough value alone and the trough and peak values using practical AUC-guided therapeutic drug monitoring (PAT) for vancomycin. In this study, factors that affect AUC were evaluated., Methods: AUCs were estimated from a single trough value and trough and peak values, and the patients were classified into those who showed a 10% or greater deviation (deviation group) and those in whom the deviation was less than 10% (no-deviation group). Risk factors related to ≥ 10% deviation of AUC were identified by univariate and multivariate analysis., Results: As a result of univariate and multivariate analysis of 30 patients in the deviation group and 344 patients in the no-deviation group, a creatinine clearance (CLcr) of ≥ 110 mL/min (odds ratio (OR) = 3.697, 95% confidence interval (CI) = 1.616-8.457, p = 0.002), heart failure with a brain natriuretic peptide (BNP) of ≥ 300 pg/mL (OR = 4.854, 95%CI = 1.199-19.656, p = 0.027), and the concomitant use of angiotensin converting enzyme inhibitor or angiotensin II receptor blocker (ACE-I/ARB) (OR = 2.544, 95%CI = 1.074-6.024, p = 0.034) were identified as risk factors of ≥ 10% deviation of AUC., Conclusions: Estimation of AUC by two-point blood sampling for the trough and peak values rather than one-point blood sampling for the trough value is suggested to improve the prediction accuracy in patients with enhanced renal function, severe heart failure, and patients using ACE-I/ARB., Competing Interests: Declarations. Conflict of Interest: KM received grant support funding from Meiji Seika Pharma Co., Ltd., Sumitomo Pharma Co., Ltd., and Shionogi & Co., Ltd., and speaker honoraria from Meiji Seika Pharma Co., Ltd. The other authors have no conflicts of interest to declare., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Venous blood is considered an acceptable alternative to arterial blood for assessment of metabolic acid-base disorders. Also, venous sampling using lithium-heparin (Li-Hep) tubes is advantageous to arterial sampling using PICO syringes, the risk of complications being lower. Usage of partly filled tubes without firm knowledge about the clinical consequences is, however, a pre-analytic consideration. The study evaluated primary acid-base parameters (pH, standardized hydrogen carbonate (HCO 3 ), standardized base excess (SBE), lactate) and co-determined parameters in venous blood stored at room temperature up to 60 min in Li-Hep tubes vs. venous blood in PICO syringes analyzed immediately. Also, 50% filled tubes stored up to 30 min were compared to filled tubes analyzed immediately. Significant differences were generally observed. Stability was parameter and time dependent (filled tubes: 30 min: pH, (preferably 15 min for optimal stability), SBE, potassium and lactate, 60 min: HCO 3 , hemoglobin, methemoglobin (MetHb), carbon monoxide hemoglobin (COHb), sodium, chloride, glucose and creatinine; 50% filled tubes: 15 min: lactate, 30 min: HCO 3 , hemoglobin, MetHb, COHb, potassium, sodium, chloride, glucose and creatinine). In conclusion, storage in filled Li-Hep tubes for 30 min generates comparable results to blood in PICO syringes for all parameters, except pCO 2 , pO 2 and sO 2 . Storage in 50% filled Li-Hep tubes is not acceptable for pH, pCO 2 , pO 2 , sO 2 and SBE, and lactate is only stable for 15 min.