Evaluating the accuracy of point of care testing compared to standard laboratory testing among inborn infants in the neonatal intensive care unit

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Methods A retrospective cohort of 118 patients with paired POC and CL tests was performed within one hour during the first 14 postnatal days. Differences and agreement were assessed using paired t-tests and Lin's concordance correlation coefficient (CCC). Results Differences were observed between POC and CL measurements: sodium (6.0 mEq/L, CCC = 0.57), potassium (0.1 mEq/dL, CCC = 0.82), chloride (4.4 mEq/L, CCC = 0.70), glucose (3.5 mg/dL, CCC = 0.97), hemoglobin (-0.04 g/dL, CCC = 0.98) and hematocrit (-0.6%, CCC = 0.97). Differences were consistent across lab results, gestational ages, birthweights, and clinical factors. Conclusions POC results differed from CL results in sodium and chloride, with little difference in potassium, glucose, hemoglobin, and hematocrit. POC testing may reduce blood volume and provide rapid results for decision-making. Health sciences/Health care/Diagnosis/Laboratory techniques and procedures Health sciences/Health care/Paediatrics Figures Figure 1 Figure 2 INTRODUCTION Point-of-care ( POC) testing offers expedited results for timely intervention in the neonatal intensive care unit ( NICU ). POC testing may also be advantageous for infants with very low birth weights because it requires a lower blood volume. POC testing for glucose is often used at the bedside for infants and adults, and its comparable performance to gold-standard central laboratory ( CL ) testing is well established ​( 1 )​. Other key analytes relevant in critically ill patients, such as lactate, INR, C-reactive protein, and procalcitonin, are validated using POC assays in infant populations ​( 2 – 4 )​. Few studies demonstrate the accuracy of sodium, bilirubin, chloride, and potassium with POC testing among infants ( 5 , 6 )​. Still, there is a paucity of evidence available across a broad spectrum of gestational age, birth weight, and illness severity, leaving gaps in our understanding of POC testing accuracy for infants of all ages and birth weights. POC testing has the potential to have significant clinical benefits for preterm infants. Notable differences between POC and CL testing include the blood volume needed for various laboratory tests and agreement for each measurement among all ages and weights. This issue is particularly concerning for the smallest and youngest infants, as their total blood volume is significantly lower than that of term infants or older children. For a 500 g infant, with an estimated total blood volume of 90 mL/kg, blood volume is estimated as ~ 45 ml. When frequent laboratory testing is required—often several times daily—cumulative blood loss can quickly become substantial. CL testing generally requires blood volumes several times that of POC tests for similar measures ​( 7 ).​ Point-of-care testing may expedite diagnosis and treatment in NICUs. However, understanding the potential for differences in results is key for optimal clinical interpretation and management, mainly when most electronic medical records include laboratory values obtained from multiple sources. The primary aim of this study was to compare the accuracy of POC testing using the GEM Premier 5 000 blood gas analyzer (Werfen, Barcelona) deployed in the POC setting​ ( 8 ) against hospital CL testing for sodium, potassium, chloride, glucose, hemoglobin, and hematocrit at our hospital. The secondary aim was to measure the differences across the range of laboratory values, gestational age, birth weight, infant severity of illness, weight loss, and fluid intake. METHODS This retrospective cohort study included inborn patients admitted to the Children's Memorial Hermann Hospital NICU (Houston, Texas) from September 2022 through May 2024 who received POC testing. Inborn infants were included if they received both POC and CL testing, drawn within one hour of each other during the first 14 postnatal days. At our center, infants receive frequent, daily laboratory testing in the first 14 postnatal days, and this period was selected to produce the most matched POC and CL samples. We identified approximately 1 000 inborn infants from the selected dates who received POC testing during hospitalization. Each eligible infant was assigned a unique numeric identifier. To obtain a representative subset for manual chart review, we selected a simple random sample of 118 infants (approximately 10–15% of the eligible population) using an online random number generator ( 14 ). No samples were excluded. The GEM Premier 5 000 blood gas analyzer ( 8 ) can test arterial, venous, capillary, and mixed venous samples with as little as 0.2 mL (or less if capillary) of blood volume. Sodium, potassium, and chloride testing on the GEM employs direct potentiometry; glucose testing involves amperometric measurement of the oxidation of hydrogen peroxide; bilirubin and total hemoglobin testing are based on optical absorbance; and hematocrit is measured by electrical conductivity. In contrast, CL electrolyte measurement is via indirect potentiometry; glucose, bilirubin, and hemoglobin are done by optical absorbance; and hematocrit is determined using hydrodynamically focused DC detection. POC results can be available in about 2 minutes. In contrast, CL turnaround time often requires up to 30–45 minutes, the bulk of which is due to specimen transit time, sample accessioning, and centrifugation. Infant demographics were recorded. A Score for Neonatal Acute Physiology and SNAP Perinatal Extension ( SNAPPE-II ) for each infant was recorded to quantify infant severity of illness and was calculated for the first 12 hours after birth using the online calculator ​( 9 ). SNAPPE-II values range from 0 to 162, with an increased SNAPPE-II score indicating a higher risk for infant mortality. Ethical approval for waiver of consent for this study was obtained from the University of Texas Houston Health Science Center Institutional Review Board. All de-identified data were securely stored in a RedCap database, and patient confidentiality was strictly maintained. For statistical analysis, POC testing and gold-standard CL testing for electrolytes were compared using a paired t-test or Wilcoxon signed-rank test as its non-parametric equivalent where appropriate. The mean difference and 95% confidence interval with a limit of agreement between POC and CL was reported for each electrolyte. In addition, Lin’s Concordance Correlation Coefficient (CCC) was calculated to quantify the agreement between the POC and CL paired values. Bland–Altman analyses were performed to quantify and visualize the magnitude of agreement and bias. Variability of the results for each of the lab measurements by potential modifiers, including extremely low birth weight (< 1 000 g), extremely low gestational ages ( 30 weeks), SNAPPE-II scores (< 32), and percentage of weight loss from birth (< 15%) were explored by including the interaction term in linear mixed model with subject ID for paired values as random effect. Daily weights were missing for 124 of the daily measurement, the percent weight loss was only calculated on days where both weights were available. All statistical tests will be conducted at 0.05 level of significance using SAS 9.4 statistical software. RESULTS This study included 118 inborn NICU patients with birth weights of 2 115 ± 1 043 g (mean ± SD) and gestational ages of 33.1 ± 5.3 weeks ( Table 1 ). The median SNAPPE-II score for the total sample was 32. Of the recorded POC samples, 69.7% were arterial blood samples, with 23.4% capillary and 6.9% venous blood samples. Table 1: Baseline infant characteristics. Characteristic n = 118 Birth weight, g 1 1 500 g 2 2 115 ± 1 043 1 (0.8) 29 (24.6) 11 (9.3) 77 (65.3) Gestational age, weeks 1 30 2 33.1 ± 5.3 10 (8.5) 29 (24.6) 79 (66.9) Male sex 2 72 (61) Race 2 White Black Asian Unknown 33 (28) 35 (29.7) 10 (8.5) 40 (33.9) C-section delivery 2 86 (74.8) SNAPPE-II score 3 32 (16, 49) Blood compartment for sample 2 Arterial Venous Capillary 545 (69.7) 54 (6.9) 183 (23.4) 1 Mean ± SD; 2 n(%); 3 Median (IQR). SNAPPE-II - Score for Neonatal Acute Physiology and SNAP Perinatal Extension(9). There were 609 paired samples for sodium, 657 pairs for potassium, 596 pairs for chloride, 593 pairs for glucose, 325 pairs for hemoglobin, and 428 pairs for hematocrit. Table 2 reports the mean differences between CL and POC testing. Comparing CL to POC results, the mean difference was 6.0 mEq/L for sodium (95% CI 5.8, 6.2, p <0.001), 0.1 mEq/L for potassium (95% CI 0.1, 0.2, p <0.001), 4.4 mEq/L for chloride (95% CI 4.2, 4.7, p <0.001), 3.5 mg/dL for glucose (95% CI 2.5, 4.4 CI, p <0.001), 0.04 g/dL for hemoglobin (95% CI -0.1, 0.01, p=0.08), and 0.6 for hematocrit (95% CI -0.8, -0.4, p<0.001). For each lab test, the upper and lower limits of agreement (mean difference ± 1.96 SD) are shown in Table 2, representing the 95% range of differences between CL and POC testing. Sodium had the lowest CCC, 0.57, whereas glucose, hemoglobin, and hematocrit had high concordance (0.95-0.99). Table 2: Comparison of CL and POC values. n (pairs) CL POC Mean Difference (95% CI) Upper limit of agreement ( Mean + 1.96 SD) Lower limit of agreement ( Mean - 1.96 SD) CCC p-value Sodium (mEq/L) 609 140.2 ± 5.3 134.2 ± 5.5 6.0 (5.8, 6.2) 10.7 (10.4, 11.1) 1.2 (0.8, 1.5) 0.57 <0.001 Potassium (mEq/L) 657 4.3 ± 1.0 4.2 ± 0.9 0.1 (0.1, 0.2) 1.2 (1.1, 1.3) -1.0 (-1.0, -0.9) 0.82 <0.001 Chloride (mEq/L) 596 107.2 ± 7.1 102.6 ± 5.8 4.4 (4.2, 4.7) 11.1 (10.6, 11.6) -2.2 (-2.7, -1.8) 0.7 <0.001 Glucose (mg/dL) 593 118.4 ± 50.7 117.0 ± 52.7 3.5 (2.5, 4.4) 27.2 (25.5, 28.8) -20.2 (-21.9, -18.6) 0.97 <0.001 Hemoglobin (g/dL) 325 13.2 ± 2.8 13.0 ± 2.6 -0.04 (-0.1, 0.01) 0.9 (0.8, 1.0) -1.0 (-1.0, -0.9) 0.98 0.08 Hematocrit 428 38.6 ± 7.5 38.8 ± 8.0 -0.6 (-0.8, -0.4) 2.9 (2.6, 3.1) -4.1 (-4.3, -3.8) 0.97 <0.001 Paired t-test, mean ± SD; CCC: Lin's concordance correlation coefficient (CCC); CI: confidence interval; CL: central lab; POC: point of care. Bland-Altman plots show variation in the difference between POC and CL values across the range of results ( Figure 1) . Differences between CL and POC were consistent across the range of results except for potassium and glucose, which had increased variability at extreme values. A forest plot ( Figure 2 ) was created to visualize the mean differences between POC and CL measurements across clinical subgroups. In Figure 2 , there was no effect modification of any of the following factors on differences between POC and CL results for sodium, potassium, chloride, and hematocrit values: birthweight (≤1 000 or > 1 000 g), gestational age (<25 weeks, 25 1/7 to 29 6/7 weeks, ≥30 weeks), SNAPPE-II score (<32 or ≥32 median sample score), weight loss from birth (<15% or ≥15%). The agreement between glucose measured at CL and POC differed by percent weight loss from birth (interaction p = 0.01). Specifically, for infants with weight loss <15%, the POC value was significantly higher than CL value [Mean difference 4.2, 95% CI (2.7, 5.7)], whereas among infants with a percent weight loss ≥15% from birth the difference was in opposite direction and not significant [Mean difference -2.6, 95% CI (-11, 5.9)]. Agreement between CL and POC hemoglobin values differed by SNAPPE-II score (interaction p = 0.017) with a mean difference (95% CI) of 0 (-0.1,0.1) for SNAPPE-II scores at ≥32 and a mean difference (95% CI) of -0.2 (-0.3, -0.1) for SNAPPE-II scores <32. DISCUSSION The primary aim of this study was to compare POC testing using the GEM Premier 5 000 blood gas analyzer set up in a POC environment ( 8 ) to CL testing for sodium, potassium, chloride, glucose, hemoglobin, and hematocrit at our hospital. POC results differed from CL results in sodium and chloride measures, with minimal difference observed in potassium, hemoglobin, and hematocrit measures. These differences remained consistent across the range of lab results and birth weights, gestational ages, and SNAPPE-II scores. While most hypothesized potential effect modifiers showed no significant interactions, possible interactions were observed for glucose and percent weight loss from birth and hemoglobin and SNAPPE-II score. However, given the relatively small sample size in this subgroup, this relationship should be interpreted with caution clinically. Assessing possible variations of result by modifiers were exploratory in this study and require replication in larger studies POC compared to CL testing in this single-center retrospective cohort study showed a consistent mean negative bias in sodium measurement of 6 mEq/L across a wide range of sodium values (120 mEq/L – 150 mEq/L), which may affect clinical decision-making when values approach thresholds for hyper- and hyponatremia. Sodium measures with moderate agreement and variability. Outside the normal range for potassium (3.5-5.0 mEq/L) and for elevated glucose (> 180 mg/dL), POC and CL testing had greater variability. Clinically, this may be explained by the general knowledge that hemolysis may produce erroneously high potassium. As a standard practice at our institution, when an elevated potassium value (> 6.5 mEq/L) is obtained by one measure, a confirmatory lab may be ordered, likely explaining the trend that we observe of greater variability at the extremes of the results range. Variability between POC and CL testing for glucose may be partly explained by the established 5–7% per hour glucose concentration loss from blood samples' glycolysis in CL testing, which can be accelerated in higher temperatures and longer wait times from collection to analysis ( 11 ). POC and CL results were similar across their ranges for other lab measures. Cost analysis was beyond the scope of this study, but the potential for blood volume savings (0.2 mL vs 1 mL per test) and faster turnaround time (2 minutes vs 30–45 minutes), as well as differences in financial cost to patients or the healthcare system, are relevant considerations in decision making about use of POC vs CL tests. POC testing may be more expensive on a per-test basis due to the limited capacity of cartridges and the greater hands-on time required to run each sample. However, the convenience and faster turnaround can offer meaningful clinical benefits that may justify the higher cost in specific settings. This study is limited by the nature of its retrospective design and small sample size, with infants randomly selected from all inborn NICU admissions during the study period. However, to our knowledge, it is the largest study to date on this topic. Increasing survival among the smallest and most premature infants, comprising 25% of our cohort, may make POC testing particularly important to limit blood volumes. Because of the retrospective nature of this study, we were unable to determine the rationale for repeated samples such as potassium or glucose, nor were we able to assess factors relevant to result reporting, such as hemolysis or sample origin (venous, arterial, or capillary). However, most samples were likely duplicated due to local clinical practice habits that include obtaining a POC blood gas and CL electrolyte measurement daily in extremely preterm infants during the first 2 postnatal weeks. CONCLUSION In this single-center retrospective study of extremely preterm infants during the first 2 postnatal weeks, we observed minimal differences in POC measures of potassium, hemoglobin, and hematocrit compared to CL measures. POC results differed more substantially from CL results in sodium and chloride measures. POC testing is generally comparable to CL testing in routine and critical care environments, with the advantage of reducing blood sample volumes while providing far more rapid results for clinical decision-making. Multicenter validation studies are necessary to enhance the generalizability of these findings. Declarations Conflicts of Interest The author(s) declare no competing interests. Availability of Data and Materials The datasets generated and analyzed during the current study are available from the corresponding author upon request. Funding This study was sponsored by the Department of Pediatrics, Division of Neonatal-Perinatal Medicine at the University of Texas Health Sciences Center, McGovern Medical School in Houston, Texas. Ethics Approval and Consent to Participate This study was approved by the University of Texas Houston Health Science Center Institutional Review Board, which granted a waiver of informed consent (IRB reference number: HSC-MS-24-0310). All procedures were conducted under the ethical standards of the institutional and/or national research committee and with the 1964 Declaration of Helsinki and its later amendments. Consent for Publication This manuscript does not contain any person's data in any form (including individual details, images, or videos); therefore, consent for publication was not required. Author Contributions Conceptualization, IP, LH, MR, MRL; methodology, IP, SS, LH; formal analysis, IP, SS, LH; investigation, IP, LH; data curation, IP, SS, LH; writing—original draft preparation, IP; writing—review and editing, IP, LH, SS, MR, BC, MRL; supervision, IP, LH; project administration, IP, LH; funding acquisition, IP, LH. All authors read and approved the final version. Acknowledgements We thank the Children's Memorial Hermann Hospital NICU nurses, patients, and families who participated in this study. We thank the Division of Neonatal-Perinatal Medicine, Department of Pediatrics, and the McGovern Summer Research Program for supporting this study. We acknowledge the statistical support provided by the Biostatistics/ Epidemiology/ Research Design (BERD) component of the Center for Clinical and Translational Sciences (CCTS) for this project that was funded through a grant 2019 (UL1TR003167) and its recent renewal in 2024 (1UM1TR004906-01) by the National Center for Advancing Translational Sciences (NCATS), awarded to the University of Texas Health Science Center at Houston. References Nichols JH, Brandler ES, Fantz CR, Fisher K, Goodman MD, Headden G, et al. A Multicenter Evaluation of a Point-of-Care Blood Glucose Meter System in Critically Ill Patients. Journal of Applied Laboratory Medicine. 2021;6(4):820–33. Goyal M, Mascarenhas D, RR P, Haribalakrishna A. 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Bruns DE, Knowler WC. Stabilization of Glucose in Blood Samples: Why It Matters. Clinical Chemistry. 2009;55(5):850–2. Cable RG, Steele WR, Melmed RS, Johnson B, Mast AE, Carey PM, et al. The difference between fingerstick and venous hemoglobin and hematocrit varies by sex and iron stores. Transfusion. 2011;52(5):1031–40. Hinds LE, Brown CL, Clark SJ. Point of care estimation of hemoglobin in neonates. Archives of Disease in Childhood Fetal & Neonatal. 2007;92(5):F378–80. Random Number Generator [Internet]. [cited 2024 Jun 4]. Available from: https://www.calculator.net/random-number-generator.html Additional Declarations There is NO conflict of interest to disclose. Cite Share Download PDF Status: Published Journal Publication published 19 Dec, 2025 Read the published version in Journal of Perinatology → Version 1 posted Editorial decision: revise 17 Sep, 2025 Review # 1 received at journal 11 Sep, 2025 Reviewer # 1 agreed at journal 26 Aug, 2025 Reviewers invited by journal 19 Aug, 2025 Submission checks completed at journal 18 Aug, 2025 Editor assigned by journal 15 Aug, 2025 First submitted to journal 15 Aug, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-7382648","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":502768519,"identity":"cfccd018-91b1-4b47-b735-0dd383f10b8c","order_by":0,"name":"Lindsay Holzapfel","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABFklEQVRIie3SP0vDQBzG8accpMslWVOE+BZ+oVCRQH0rkQxZInQVaikU6lKd9V1kynzhIF3ibifr4uSgi2Qo4sXaajGpq8N9h+Pg+HB/OECn+4dZDHDW09ajAMEF+GYxqCXGN2FUkS4MRcQ+gh0CnI7/JG0zW5RDiSMwiJfBRZQ8XAn2Gvdht2OqP5gV+jyXOB4zZDc0P0tyK0CWhujMnhsI7x3AkCBhC8kpV4STIupe90278F6nfK8Ig1xRHtGGnOwhjjn9IqBhsCXkNJKub15HnKS6y4yEd5vHJO7SkDvF06CO2HbhLco336X5pLUsV6NDSxbe8jztu/ZlmNS+8roJV29cJT9HgR9/oKHRr4lOp9Pptn0A25pdqWV31UgAAAAASUVORK5CYII=","orcid":"https://orcid.org/0000-0002-1830-5705","institution":"University of Texas, Houston Health Science Center","correspondingAuthor":true,"prefix":"","firstName":"Lindsay","middleName":"","lastName":"Holzapfel","suffix":""},{"id":502768520,"identity":"cabcd91a-328d-4f1c-8028-99ae2377ca8d","order_by":1,"name":"Isha Parikh","email":"","orcid":"","institution":"University of Texas, Houston Health Science Center","correspondingAuthor":false,"prefix":"","firstName":"Isha","middleName":"","lastName":"Parikh","suffix":""},{"id":502768521,"identity":"24e4faa7-e394-447c-abd8-54f3e73b5758","order_by":2,"name":"Sepideh Saroukhani","email":"","orcid":"","institution":"University of Texas, Houston Health Science Center","correspondingAuthor":false,"prefix":"","firstName":"Sepideh","middleName":"","lastName":"Saroukhani","suffix":""},{"id":502768522,"identity":"c60f3e87-356b-4f2a-8120-1e3cf36b875c","order_by":3,"name":"Matthew Rysavy","email":"","orcid":"https://orcid.org/0000-0002-1209-6607","institution":"University of Texas Health Science Center at Houston","correspondingAuthor":false,"prefix":"","firstName":"Matthew","middleName":"","lastName":"Rysavy","suffix":""},{"id":502768523,"identity":"f1e8e5fe-5686-4f67-8c0a-2c29a63b9eae","order_by":4,"name":"Mar Romero-Lopez","email":"","orcid":"https://orcid.org/0000-0002-5890-7786","institution":"University of Texas, Houston Health Science Center","correspondingAuthor":false,"prefix":"","firstName":"Mar","middleName":"","lastName":"Romero-Lopez","suffix":""},{"id":502768524,"identity":"1b0ba60f-da7a-47b4-be3d-36ae3dbab0df","order_by":5,"name":"Brian Chang","email":"","orcid":"","institution":"University of Texas, Houston Health Science Center","correspondingAuthor":false,"prefix":"","firstName":"Brian","middleName":"","lastName":"Chang","suffix":""}],"badges":[],"createdAt":"2025-08-15 15:45:49","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-7382648/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-7382648/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41372-025-02543-3","type":"published","date":"2025-12-19T05:00:00+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":90304576,"identity":"a37498c6-1878-4059-aff5-1cd923ca8dfa","added_by":"auto","created_at":"2025-09-01 09:17:56","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":478836,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eBland Altman Plots of Central Laboratory vs Point-of-Care.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePanel A:\u003c/strong\u003e Bland Altman plot of Sodium CL vs POC values. Dashed lines show 95% limits of agreement, and the solid line indicates the mean difference between the CL and POC. Positive mean difference (bias) of 6 between CL and POC. 95% Confidence interval (CI) Limits of agreement are between 1.2 and 10.7.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePanel B: \u003c/strong\u003eBland Altman plot of Potassium CL vs POC values. There is a slightly positive mean difference (bias) of 0.1 between CL and POC. 95% Limits of agreement are between -0.96 and 1.2. Some variation of the results above the potassium value of 6.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePanel C: \u003c/strong\u003eBland Altman plot of Chloride CL vs POC values. Positive mean difference (bias) of 4.4 between CL and POC. 95% Limits of agreement are between -2.2 and 11.1.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePanel D:\u003c/strong\u003e Bland Altman plot of Glucose CL vs POC values. Positive mean difference (bias) of 3.4 between CL and POC. 95% Limits of agreement are between -20.2 and 27.2. Some variation of results above the glucose value of 200.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePanel E:\u003c/strong\u003e Bland Altman plot of Hemoglobin CL vs POC values. Negative mean difference (bias) of -0.05 between CL and POC. 95% Limits of agreement are between -1.0 and 0.9\u003cstrong\u003e.\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003ePanel F:\u003c/strong\u003e Bland Altman plot of Hematocrit CL vs POC values. \u003cstrong\u003eNegative mean difference (bias) of -0.6 between CL and POC. 95% Limits of agreement are between -4.1 and 2.9.\u003c/strong\u003e\u003c/p\u003e","description":"","filename":"Figure1.png","url":"https://assets-eu.researchsquare.com/files/rs-7382648/v1/b0e98ec387719d011d54badf.png"},{"id":90303828,"identity":"e1dd2413-e215-420f-95a1-001616c35c09","added_by":"auto","created_at":"2025-09-01 09:09:56","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":756322,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eComparison of POC and CL values by potential modifiers\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eComparison of paired POC and CL measurements for sodium, potassium, chloride, glucose, hemoglobin, and hematocrit, stratified by birthweight, gestational age, SNAPPE-II score, and weight loss from birth. The table presents mean ± SD, mean difference (95% CI), and interaction \u003cem\u003ep\u003c/em\u003e-values. The accompanying forest plots display mean differences with 95% Cis. The vertical dashed line represents no difference (total agreement) between POC and CL. Filled squares indicate mean differences, with bars showing precision. Points to the right indicate POC overestimation and to the left indicate underestimation. CIs crossing the dashed line indicate no statistically significant difference.\u003c/p\u003e","description":"","filename":"Figure2.png","url":"https://assets-eu.researchsquare.com/files/rs-7382648/v1/b9965a8f78aef4ffd1f37882.png"},{"id":98664074,"identity":"25b43731-e145-4b8e-bb84-cbad9647f814","added_by":"auto","created_at":"2025-12-20 08:09:20","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1915694,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-7382648/v1/81378bd0-6faf-4ddf-9152-e9028dbc8a52.pdf"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e conflict of interest to disclose.","formattedTitle":"Evaluating the accuracy of point of care testing compared to standard laboratory testing among inborn infants in the neonatal intensive care unit","fulltext":[{"header":"INTRODUCTION","content":"\u003cp\u003ePoint-of-care (\u003cb\u003ePOC)\u003c/b\u003e testing offers expedited results for timely intervention in the neonatal intensive care unit (\u003cb\u003eNICU\u003c/b\u003e). POC testing may also be advantageous for infants with very low birth weights because it requires a lower blood volume. POC testing for glucose is often used at the bedside for infants and adults, and its comparable performance to gold-standard central laboratory (\u003cb\u003eCL\u003c/b\u003e) testing is well established ​(\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e)​. Other key analytes relevant in critically ill patients, such as lactate, INR, C-reactive protein, and procalcitonin, are validated using POC assays in infant populations ​(\u003cspan additionalcitationids=\"CR3\" citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e)​. Few studies demonstrate the accuracy of sodium, bilirubin, chloride, and potassium with POC testing among infants (\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e)​. Still, there is a paucity of evidence available across a broad spectrum of gestational age, birth weight, and illness severity, leaving gaps in our understanding of POC testing accuracy for infants of all ages and birth weights.\u003c/p\u003e\u003cp\u003ePOC testing has the potential to have significant clinical benefits for preterm infants. Notable differences between POC and CL testing include the blood volume needed for various laboratory tests and agreement for each measurement among all ages and weights. This issue is particularly concerning for the smallest and youngest infants, as their total blood volume is significantly lower than that of term infants or older children. For a 500 g infant, with an estimated total blood volume of 90 mL/kg, blood volume is estimated as ~\u0026thinsp;45 ml. When frequent laboratory testing is required\u0026mdash;often several times daily\u0026mdash;cumulative blood loss can quickly become substantial. CL testing generally requires blood volumes several times that of POC tests for similar measures ​(\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e).​\u003c/p\u003e\u003cp\u003ePoint-of-care testing may expedite diagnosis and treatment in NICUs. However, understanding the potential for differences in results is key for optimal clinical interpretation and management, mainly when most electronic medical records include laboratory values obtained from multiple sources. The primary aim of this study was to compare the accuracy of POC testing using the GEM Premier 5 000 blood gas analyzer (Werfen, Barcelona) deployed in the POC setting​ (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e) against hospital CL testing for sodium, potassium, chloride, glucose, hemoglobin, and hematocrit at our hospital. The secondary aim was to measure the differences across the range of laboratory values, gestational age, birth weight, infant severity of illness, weight loss, and fluid intake.\u003c/p\u003e"},{"header":"METHODS","content":"\u003cp\u003eThis retrospective cohort study included inborn patients admitted to the Children's Memorial Hermann Hospital NICU (Houston, Texas) from September 2022 through May 2024 who received POC testing. Inborn infants were included if they received both POC and CL testing, drawn within one hour of each other during the first 14 postnatal days. At our center, infants receive frequent, daily laboratory testing in the first 14 postnatal days, and this period was selected to produce the most matched POC and CL samples. We identified approximately 1 000 inborn infants from the selected dates who received POC testing during hospitalization. Each eligible infant was assigned a unique numeric identifier. To obtain a representative subset for manual chart review, we selected a simple random sample of 118 infants (approximately 10\u0026ndash;15% of the eligible population) using an online random number generator (\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e). No samples were excluded.\u003c/p\u003e\u003cp\u003eThe GEM Premier 5 000 blood gas analyzer (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e) can test arterial, venous, capillary, and mixed venous samples with as little as 0.2 mL (or less if capillary) of blood volume. Sodium, potassium, and chloride testing on the GEM employs direct potentiometry; glucose testing involves amperometric measurement of the oxidation of hydrogen peroxide; bilirubin and total hemoglobin testing are based on optical absorbance; and hematocrit is measured by electrical conductivity. In contrast, CL electrolyte measurement is via indirect potentiometry; glucose, bilirubin, and hemoglobin are done by optical absorbance; and hematocrit is determined using hydrodynamically focused DC detection. POC results can be available in about 2 minutes. In contrast, CL turnaround time often requires up to 30\u0026ndash;45 minutes, the bulk of which is due to specimen transit time, sample accessioning, and centrifugation.\u003c/p\u003e\u003cp\u003eInfant demographics were recorded. A Score for Neonatal Acute Physiology and SNAP Perinatal Extension (\u003cb\u003eSNAPPE-II\u003c/b\u003e) for each infant was recorded to quantify infant severity of illness and was calculated for the first 12 hours after birth using the online calculator ​(\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e). SNAPPE-II values range from 0 to 162, with an increased SNAPPE-II score indicating a higher risk for infant mortality. Ethical approval for waiver of consent for this study was obtained from the University of Texas Houston Health Science Center Institutional Review Board. All de-identified data were securely stored in a RedCap database, and patient confidentiality was strictly maintained.\u003c/p\u003e\u003cp\u003eFor statistical analysis, POC testing and gold-standard CL testing for electrolytes were compared using a paired t-test or Wilcoxon signed-rank test as its non-parametric equivalent where appropriate. The mean difference and 95% confidence interval with a limit of agreement between POC and CL was reported for each electrolyte. In addition, Lin\u0026rsquo;s Concordance Correlation Coefficient (CCC) was calculated to quantify the agreement between the POC and CL paired values. Bland\u0026ndash;Altman analyses were performed to quantify and visualize the magnitude of agreement and bias. Variability of the results for each of the lab measurements by potential modifiers, including extremely low birth weight (\u0026lt;\u0026thinsp;1 000 g), extremely low gestational ages (\u0026lt;\u0026thinsp;25 weeks, 25 1/7 to 29 6/7 weeks, \u0026gt;\u0026thinsp;30 weeks), SNAPPE-II scores (\u0026lt;\u0026thinsp;32), and percentage of weight loss from birth (\u0026lt;\u0026thinsp;15%) were explored by including the interaction term in linear mixed model with subject ID for paired values as random effect. Daily weights were missing for 124 of the daily measurement, the percent weight loss was only calculated on days where both weights were available. All statistical tests will be conducted at 0.05 level of significance using SAS 9.4 statistical software.\u003c/p\u003e"},{"header":"RESULTS","content":"\u003cp\u003eThis study included 118 inborn NICU patients with birth weights of 2 115 \u0026plusmn; 1 043 g (mean \u0026plusmn; SD) and gestational ages of 33.1 \u0026plusmn; 5.3 weeks (\u003cstrong\u003eTable 1\u003c/strong\u003e). The median SNAPPE-II score for the total sample was 32. Of the recorded POC samples, 69.7% were arterial blood samples, with 23.4% capillary and 6.9% venous blood samples.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 1:\u0026nbsp;\u003c/strong\u003eBaseline infant characteristics.\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"599\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 293px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCharacteristic\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 306px;\"\u003e\n \u003cp\u003e\u003cstrong\u003en = 118\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 293px;\"\u003e\n \u003cp\u003eBirth weight, \u003cem\u003eg\u003csup\u003e1\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026lt;500 g\u003cem\u003e\u003csup\u003e2\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 501-1 000 g\u003cem\u003e\u003csup\u003e2\u003c/sup\u003e\u003c/em\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 1 001-1 500 g\u003cem\u003e\u003csup\u003e2\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026gt;1 500 g\u003cem\u003e\u003csup\u003e2\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 306px;\"\u003e\n \u003cp\u003e2 115 \u0026plusmn; 1 043\u003c/p\u003e\n \u003cp\u003e1 (0.8)\u003c/p\u003e\n \u003cp\u003e29 (24.6)\u003c/p\u003e\n \u003cp\u003e11 (9.3)\u003c/p\u003e\n \u003cp\u003e77 (65.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 293px;\"\u003e\n \u003cp\u003eGestational age, \u003cem\u003eweeks\u003csup\u003e1\u003c/sup\u003e\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026lt;25\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; 25 1/7 to 29 6/7\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026gt;30\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 306px;\"\u003e\n \u003cp\u003e33.1 \u0026plusmn; 5.3\u003c/p\u003e\n \u003cp\u003e10 (8.5)\u003c/p\u003e\n \u003cp\u003e29 (24.6)\u003c/p\u003e\n \u003cp\u003e79 (66.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 293px;\"\u003e\n \u003cp\u003eMale sex\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 306px;\"\u003e\n \u003cp\u003e72 (61)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 293px;\"\u003e\n \u003cp\u003eRace\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; White \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Black\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Asian \u0026nbsp;\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; Unknown\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 306px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e33 (28)\u003c/p\u003e\n \u003cp\u003e35 (29.7)\u003c/p\u003e\n \u003cp\u003e10 (8.5)\u003c/p\u003e\n \u003cp\u003e40 (33.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 293px;\"\u003e\n \u003cp\u003eC-section delivery\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 306px;\"\u003e\n \u003cp\u003e86 (74.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 293px;\"\u003e\n \u003cp\u003eSNAPPE-II score\u003cem\u003e\u003csup\u003e3\u003c/sup\u003e\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 306px;\"\u003e\n \u003cp\u003e32 (16, 49)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd valign=\"top\" style=\"width: 293px;\"\u003e\n \u003cp\u003eBlood compartment for sample\u003csup\u003e2\u003c/sup\u003e\u003c/p\u003e\n \u003cp\u003eArterial\u003c/p\u003e\n \u003cp\u003eVenous\u003c/p\u003e\n \u003cp\u003e\u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; \u0026nbsp; Capillary\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 306px;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003cp\u003e545 (69.7)\u003c/p\u003e\n \u003cp\u003e54 (6.9)\u003c/p\u003e\n \u003cp\u003e183 (23.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cem\u003e\u003csup\u003e1\u003c/sup\u003e\u003c/em\u003e\u003cem\u003eMean \u0026plusmn; SD; \u003csup\u003e2\u003c/sup\u003en(%); \u003csup\u003e3\u003c/sup\u003eMedian (IQR). SNAPPE-II - Score for Neonatal Acute Physiology and SNAP Perinatal Extension(9).\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eThere were 609 paired samples for sodium, 657 pairs for potassium, 596 pairs for chloride, 593 pairs for glucose, 325 pairs for hemoglobin, and 428 pairs for hematocrit. \u003cstrong\u003eTable 2\u003c/strong\u003e reports the mean differences between CL and POC testing. Comparing CL to POC results, the mean difference was 6.0 mEq/L for sodium (95% CI 5.8, 6.2, p \u0026lt;0.001), 0.1 mEq/L for potassium (95% CI 0.1, 0.2, p \u0026lt;0.001), 4.4 mEq/L for chloride (95% CI 4.2, \u0026nbsp;4.7, p \u0026lt;0.001), 3.5 mg/dL for glucose (95% CI 2.5, \u0026nbsp;4.4 CI, p \u0026lt;0.001), 0.04 g/dL for hemoglobin (95% CI -0.1, 0.01, p=0.08), and 0.6 for hematocrit (95% CI -0.8, -0.4, p\u0026lt;0.001). For each lab test, the upper and lower limits of agreement (mean difference \u0026plusmn; 1.96 SD) are shown in Table 2, representing the 95% range of differences between CL and POC testing. Sodium had the lowest CCC, 0.57, whereas glucose, hemoglobin, and hematocrit had high concordance (0.95-0.99).\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eTable 2:\u003c/strong\u003e Comparison of CL and POC values.\u003c/p\u003e\n\u003ctable border=\"1\" cellspacing=\"0\" cellpadding=\"0\" width=\"654\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 101px;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e\u003cstrong\u003en (pairs)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCL\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ePOC\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eMean Difference\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(95% CI)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eUpper limit of agreement\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(\u003c/strong\u003e\u003cstrong\u003eMean + 1.96 SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eLower limit of agreement\u003c/strong\u003e\u003c/p\u003e\n \u003cp\u003e\u003cstrong\u003e(\u003c/strong\u003e\u003cstrong\u003eMean - 1.96 SD)\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e\u003cstrong\u003eCCC\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u003cstrong\u003ep-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003eSodium\u0026nbsp;(mEq/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e609\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e140.2 \u0026plusmn; 5.3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e134.2 \u0026plusmn; 5.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e6.0 (5.8, 6.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e10.7 (10.4, 11.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e1.2 (0.8, 1.5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e0.57\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003ePotassium\u0026nbsp;(mEq/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e657\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e4.3 \u0026plusmn; 1.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e4.2 \u0026plusmn; 0.9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e0.1 (0.1, 0.2)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e1.2 (1.1, 1.3)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e-1.0 (-1.0, -0.9)\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e0.82\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003eChloride\u0026nbsp;(mEq/L)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e596\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e107.2 \u0026plusmn; 7.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e102.6 \u0026plusmn; 5.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e4.4 (4.2, 4.7)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e11.1 (10.6, 11.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e-2.2 (-2.7, -1.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e0.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003eGlucose\u0026nbsp;(mg/dL)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e593\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e118.4 \u0026plusmn; 50.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e117.0 \u0026plusmn; 52.7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e3.5 (2.5, 4.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e27.2 (25.5, 28.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e-20.2 (-21.9, -18.6)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e0.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003eHemoglobin\u0026nbsp;(g/dL)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e325\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e13.2 \u0026plusmn; 2.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e13.0 \u0026plusmn; 2.6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e-0.04 (-0.1, 0.01)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e0.9 (0.8, 1.0)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e-1.0 (-1.0, -0.9)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e0.98\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e0.08\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd style=\"width: 101px;\"\u003e\n \u003cp\u003eHematocrit\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 54px;\"\u003e\n \u003cp\u003e428\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e38.6 \u0026plusmn; 7.5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 66px;\"\u003e\n \u003cp\u003e38.8 \u0026plusmn; 8.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e-0.6 (-0.8, -0.4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 90px;\"\u003e\n \u003cp\u003e2.9 (2.6, 3.1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 96px;\"\u003e\n \u003cp\u003e-4.1 (-4.3, -3.8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 48px;\"\u003e\n \u003cp\u003e0.97\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd style=\"width: 43px;\"\u003e\n \u003cp\u003e\u0026lt;0.001\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n\u003c/table\u003e\n\u003cp\u003e\u003cem\u003ePaired t-test, mean \u0026plusmn; SD; CCC: Lin\u0026apos;s concordance correlation coefficient (CCC); CI: confidence interval; CL: central lab; POC: point of care.\u0026nbsp;\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eBland-Altman plots show variation in the difference between POC and CL values across the range of results (\u003cstrong\u003eFigure 1)\u003c/strong\u003e. Differences between CL and POC were consistent across the range of results except for potassium and glucose, which had increased variability at extreme values.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003eA forest plot (\u003cstrong\u003eFigure 2\u003c/strong\u003e) was created to visualize the mean differences between POC and CL measurements across clinical subgroups. In \u003cstrong\u003eFigure 2\u003c/strong\u003e, there was no effect modification of any of the following factors on differences between POC and CL results for sodium, potassium, chloride, and hematocrit values: birthweight (\u0026le;1 000 or \u0026gt; 1 000 g), gestational age (\u0026lt;25 weeks, 25 1/7 to 29 6/7 weeks, \u0026ge;30 weeks), SNAPPE-II score (\u0026lt;32 or \u0026ge;32 median sample score), weight loss from birth (\u0026lt;15% or \u0026ge;15%). The agreement between glucose measured at CL and POC differed by percent weight loss from birth (interaction p = 0.01). Specifically, for infants with weight loss \u0026lt;15%, the POC value was significantly higher than CL value [Mean difference 4.2, 95% CI (2.7, 5.7)], whereas among infants with a percent weight loss \u0026ge;15% from birth the difference was in opposite direction and not significant [Mean difference -2.6, 95% CI (-11, 5.9)]. Agreement between CL and POC hemoglobin values differed by SNAPPE-II score (interaction p = 0.017) with a mean difference (95% CI) of 0 (-0.1,0.1) for SNAPPE-II scores at \u0026ge;32 and a mean difference (95% CI) of -0.2 (-0.3, -0.1) for SNAPPE-II scores \u0026lt;32.\u003c/p\u003e"},{"header":"DISCUSSION","content":"\u003cp\u003eThe primary aim of this study was to compare POC testing using the GEM Premier 5 000 blood gas analyzer set up in a POC environment (\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e) to CL testing for sodium, potassium, chloride, glucose, hemoglobin, and hematocrit at our hospital. POC results differed from CL results in sodium and chloride measures, with minimal difference observed in potassium, hemoglobin, and hematocrit measures. These differences remained consistent across the range of lab results and birth weights, gestational ages, and SNAPPE-II scores. While most hypothesized potential effect modifiers showed no significant interactions, possible interactions were observed for glucose and percent weight loss from birth and hemoglobin and SNAPPE-II score. However, given the relatively small sample size in this subgroup, this relationship should be interpreted with caution clinically. Assessing possible variations of result by modifiers were exploratory in this study and require replication in larger studies\u003c/p\u003e\u003cp\u003ePOC compared to CL testing in this single-center retrospective cohort study showed a consistent mean negative bias in sodium measurement of 6 mEq/L across a wide range of sodium values (120 mEq/L \u0026ndash; 150 mEq/L), which may affect clinical decision-making when values approach thresholds for hyper- and hyponatremia. Sodium measures with moderate agreement and variability. Outside the normal range for potassium (3.5-5.0 mEq/L) and for elevated glucose (\u0026gt;\u0026thinsp;180 mg/dL), POC and CL testing had greater variability. Clinically, this may be explained by the general knowledge that hemolysis may produce erroneously high potassium. As a standard practice at our institution, when an elevated potassium value (\u0026gt;\u0026thinsp;6.5 mEq/L) is obtained by one measure, a confirmatory lab may be ordered, likely explaining the trend that we observe of greater variability at the extremes of the results range. Variability between POC and CL testing for glucose may be partly explained by the established 5\u0026ndash;7% per hour glucose concentration loss from blood samples' glycolysis in CL testing, which can be accelerated in higher temperatures and longer wait times from collection to analysis (\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e). POC and CL results were similar across their ranges for other lab measures.\u003c/p\u003e\u003cp\u003eCost analysis was beyond the scope of this study, but the potential for blood volume savings (0.2 mL vs 1 mL per test) and faster turnaround time (2 minutes vs 30\u0026ndash;45 minutes), as well as differences in financial cost to patients or the healthcare system, are relevant considerations in decision making about use of POC vs CL tests. POC testing may be more expensive on a per-test basis due to the limited capacity of cartridges and the greater hands-on time required to run each sample. However, the convenience and faster turnaround can offer meaningful clinical benefits that may justify the higher cost in specific settings.\u003c/p\u003e\u003cp\u003eThis study is limited by the nature of its retrospective design and small sample size, with infants randomly selected from all inborn NICU admissions during the study period. However, to our knowledge, it is the largest study to date on this topic. Increasing survival among the smallest and most premature infants, comprising 25% of our cohort, may make POC testing particularly important to limit blood volumes. Because of the retrospective nature of this study, we were unable to determine the rationale for repeated samples such as potassium or glucose, nor were we able to assess factors relevant to result reporting, such as hemolysis or sample origin (venous, arterial, or capillary). However, most samples were likely duplicated due to local clinical practice habits that include obtaining a POC blood gas and CL electrolyte measurement daily in extremely preterm infants during the first 2 postnatal weeks.\u003c/p\u003e"},{"header":"CONCLUSION","content":"\u003cp\u003eIn this single-center retrospective study of extremely preterm infants during the first 2 postnatal weeks, we observed minimal differences in POC measures of potassium, hemoglobin, and hematocrit compared to CL measures. POC results differed more substantially from CL results in sodium and chloride measures. POC testing is generally comparable to CL testing in routine and critical care environments, with the advantage of reducing blood sample volumes while providing far more rapid results for clinical decision-making. Multicenter validation studies are necessary to enhance the generalizability of these findings.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eConflicts of Interest\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe author(s) declare no competing interests.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAvailability of Data and Materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets generated and analyzed during the current study are available from the corresponding author upon request.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was sponsored by the Department of Pediatrics, Division of Neonatal-Perinatal Medicine at the University of Texas Health Sciences Center, McGovern Medical School in Houston, Texas.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics Approval and Consent to Participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the University of Texas Houston Health Science Center Institutional Review Board, which granted a waiver of informed consent (IRB reference number: HSC-MS-24-0310). All procedures were conducted under the ethical standards of the institutional and/or national research committee and with the 1964 Declaration of Helsinki and its later amendments.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for Publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis manuscript does not contain any person's data in any form (including individual details, images, or videos); therefore, consent for publication was not required.\u003c/p\u003e\n\u003cp\u003e\u003cem\u003e\u003cstrong\u003eAuthor Contributions\u003c/strong\u003e\u003c/em\u003e\u003c/p\u003e\n\u003cp\u003eConceptualization, IP, LH, MR, MRL; methodology, IP, SS, LH; formal analysis, IP, SS, LH; investigation, IP, LH; data curation, IP, SS, LH; writing—original draft preparation, IP; writing—review and editing, IP, LH, SS, MR, BC, MRL; supervision, IP, LH; project administration, IP, LH; funding acquisition, IP, LH. All authors read and approved the final version.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe thank the Children's Memorial Hermann Hospital NICU nurses, patients, and families who participated in this study. We thank the Division of Neonatal-Perinatal Medicine, Department of Pediatrics, and the McGovern Summer Research Program for supporting this study. We acknowledge the statistical support provided by the Biostatistics/ Epidemiology/ Research Design (BERD) component of the Center for Clinical and Translational Sciences (CCTS) for this project that was funded through a grant 2019 (UL1TR003167) and its recent renewal in 2024 (1UM1TR004906-01) by the National Center for Advancing Translational Sciences (NCATS), awarded to the University of Texas Health Science Center at Houston.\u0026nbsp;\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eNichols JH, Brandler ES, Fantz CR, Fisher K, Goodman MD, Headden G, et al. A Multicenter Evaluation of a Point-of-Care Blood Glucose Meter System in Critically Ill Patients. Journal of Applied Laboratory Medicine. 2021;6(4):820\u0026ndash;33.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eGoyal M, Mascarenhas D, RR P, Haribalakrishna A. 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Comparative analysis of the quantitative point-of-care CareSTART\u0026trade; total bilirubin with central laboratory total bilirubin assays in neonatal blood samples. Medicine [Internet]. 2024;103(21):e38267. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://journals.lww.com/\u003c/span\u003e\u003cspan address=\"https://journals.lww.com/\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/MD.0000000000038267\u003c/span\u003e\u003cspan address=\"10.1097/MD.0000000000038267\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003ePapadea CN, Papadea C, Foster J, Grant S, Ballard SA, Iv JCC, et al. Evaluation of the i-STAT Portable Clinical Analyzer for Point-of-Care Blood Testing in the Intensive Care Units of a University Children's Hospital. 2002.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eMahieu L, Marien A, De Dooy J, Mahieu M, Mahieu H, Van Hoof V. Implementation of a multi-parameter Point-of-Care-blood test analyzer reduces central laboratory testing and need for blood transfusions in very low birth weight infants. Clinica Chimica Acta. 2012;413(1\u0026ndash;2):325\u0026ndash;30.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eLaboratory I. GEM Premier 5000 Manual. 2020\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRichardson DK, Corcoran JD, Escobar GJ, Lee SK. SNAP-II and SNAPPE-II: Simplified newborn illness severity and mortality risk scores. Journal of Pediatrics. 2001;138(1):92\u0026ndash;100.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eChoi HY, Corder W, Tefera E, Abubakar KM. Comparison of Point-of-Care versus Central Laboratory Testing of Electrolytes, Hemoglobin, and Bilirubin in Neonates. Am J Perinatol. 2022;39(16):1786\u0026ndash;91.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eBruns DE, Knowler WC. Stabilization of Glucose in Blood Samples: Why It Matters. Clinical Chemistry. 2009;55(5):850\u0026ndash;2.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eCable RG, Steele WR, Melmed RS, Johnson B, Mast AE, Carey PM, et al. The difference between fingerstick and venous hemoglobin and hematocrit varies by sex and iron stores. Transfusion. 2011;52(5):1031\u0026ndash;40.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eHinds LE, Brown CL, Clark SJ. Point of care estimation of hemoglobin in neonates. Archives of Disease in Childhood Fetal \u0026amp; Neonatal. 2007;92(5):F378\u0026ndash;80.\u003c/span\u003e\u003c/li\u003e\u003cli\u003e\u003cspan\u003eRandom Number Generator [Internet]. [cited 2024 Jun 4]. Available from: \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.calculator.net/random-number-generator.html\u003c/span\u003e\u003cspan address=\"https://www.calculator.net/random-number-generator.html\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"journal-of-perinatology","isNatureJournal":false,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"jp","sideBox":"Learn more about [Journal of Perinatology](http://www.nature.com/jp/)","snPcode":"41372","submissionUrl":"https://mts-jper.nature.com/cgi-bin/main.plex","title":"Journal of Perinatology","twitterHandle":"@jperinatology","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":false},"keywords":"","lastPublishedDoi":"10.21203/rs.3.rs-7382648/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-7382648/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003ch2\u003eObjective\u003c/h2\u003e\u003cp\u003ePoint-of-care (POC) testing offers expedited results with lower blood volume requirements than central laboratory (CL) tests, particularly beneficial for low-birth-weight infants.\u003c/p\u003e\u003ch2\u003eMethods\u003c/h2\u003e\u003cp\u003eA retrospective cohort of 118 patients with paired POC and CL tests was performed within one hour during the first 14 postnatal days. Differences and agreement were assessed using paired t-tests and Lin's concordance correlation coefficient (CCC).\u003c/p\u003e\u003ch2\u003eResults\u003c/h2\u003e\u003cp\u003eDifferences were observed between POC and CL measurements: sodium (6.0 mEq/L, CCC\u0026thinsp;=\u0026thinsp;0.57), potassium (0.1 mEq/dL, CCC\u0026thinsp;=\u0026thinsp;0.82), chloride (4.4 mEq/L, CCC\u0026thinsp;=\u0026thinsp;0.70), glucose (3.5 mg/dL, CCC\u0026thinsp;=\u0026thinsp;0.97), hemoglobin (-0.04 g/dL, CCC\u0026thinsp;=\u0026thinsp;0.98) and hematocrit (-0.6%, CCC\u0026thinsp;=\u0026thinsp;0.97). Differences were consistent across lab results, gestational ages, birthweights, and clinical factors.\u003c/p\u003e\u003ch2\u003eConclusions\u003c/h2\u003e\u003cp\u003ePOC results differed from CL results in sodium and chloride, with little difference in potassium, glucose, hemoglobin, and hematocrit. POC testing may reduce blood volume and provide rapid results for decision-making.\u003c/p\u003e","manuscriptTitle":"Evaluating the accuracy of point of care testing compared to standard laboratory testing among inborn infants in the neonatal intensive care unit","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-09-01 09:09:36","doi":"10.21203/rs.3.rs-7382648/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"revise","date":"2025-09-17T14:49:45+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"This content is not available.","date":"2025-09-11T11:04:41+00:00","index":1,"fulltext":"This content is not available."},{"type":"reviewerAgreed","content":"This content is not available.","date":"2025-08-26T09:38:50+00:00","index":1,"fulltext":"This content is not available."},{"type":"reviewersInvited","content":"","date":"2025-08-19T21:32:47+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2025-08-18T13:29:37+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2025-08-15T15:42:04+00:00","index":"","fulltext":""},{"type":"submitted","content":"Journal of Perinatology","date":"2025-08-15T15:42:04+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"journal-of-perinatology","isNatureJournal":false,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"jp","sideBox":"Learn more about [Journal of Perinatology](http://www.nature.com/jp/)","snPcode":"41372","submissionUrl":"https://mts-jper.nature.com/cgi-bin/main.plex","title":"Journal of Perinatology","twitterHandle":"@jperinatology","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature AJ","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"89def40c-5fb7-43f5-96d6-551e780e5cb5","owner":[],"postedDate":"September 1st, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":53407546,"name":"Health sciences/Health care/Diagnosis/Laboratory techniques and procedures"},{"id":53407547,"name":"Health sciences/Health care/Paediatrics"}],"tags":[],"updatedAt":"2025-12-20T08:09:09+00:00","versionOfRecord":{"articleIdentity":"rs-7382648","link":"https://doi.org/10.1038/s41372-025-02543-3","journal":{"identity":"journal-of-perinatology","isVorOnly":false,"title":"Journal of Perinatology"},"publishedOn":"2025-12-19 05:00:00","publishedOnDateReadable":"December 19th, 2025"},"versionCreatedAt":"2025-09-01 09:09:36","video":"","vorDoi":"10.1038/s41372-025-02543-3","vorDoiUrl":"https://doi.org/10.1038/s41372-025-02543-3","workflowStages":[]},"version":"v1","identity":"rs-7382648","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-7382648","identity":"rs-7382648","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}